Proposed Rule2022-25599
Reliability Standards To Address Inverter-Based Resources
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
December 6, 2022
Issuing agencies
Energy DepartmentFederal Energy Regulatory Commission
Abstract
The Federal Energy Regulatory Commission (Commission) proposes to direct the North American Electric Reliability Corporation (NERC), the Commission-certified Electric Reliability Organization (ERO), to develop new or modified Reliability Standards that address the following reliability gaps related to inverter-based resources (IBR): data sharing; model validation; planning and operational studies; and performance requirements. Further, the Commission proposes to direct NERC to submit to the Commission a compliance filing within 90 days of the effective date of the final rule in this proceeding that includes a detailed, comprehensive standards development and implementation plan to ensure all new or modified Reliability Standards necessary to address the IBR-related reliability gaps identified in the final rule are submitted to the Commission within 36 months of Commission approval of the plan.
Full Text
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<title>Federal Register, Volume 87 Issue 233 (Tuesday, December 6, 2022)</title>
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[Federal Register Volume 87, Number 233 (Tuesday, December 6, 2022)]
[Proposed Rules]
[Pages 74541-74563]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2022-25599]
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DEPARTMENT OF ENERGY
Federal Energy Regulatory Commission
18 CFR Part 40
[Docket No. RM22-12-000]
Reliability Standards To Address Inverter-Based Resources
AGENCY: Federal Energy Regulatory Commission, Department of Energy
(DOE).
ACTION: Notice of proposed rulemaking.
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SUMMARY: The Federal Energy Regulatory Commission (Commission) proposes
to direct the North American Electric Reliability Corporation (NERC),
the Commission-certified Electric Reliability Organization (ERO), to
develop new or modified Reliability Standards that address the
following reliability gaps related to inverter-based resources (IBR):
data sharing; model validation; planning and operational studies; and
performance requirements. Further, the Commission proposes to direct
NERC to submit to the Commission a compliance filing within 90 days of
the effective date of the final rule in this proceeding that includes a
detailed, comprehensive standards development and implementation plan
to ensure all new or modified Reliability Standards necessary to
address the IBR-related reliability gaps identified in the final rule
are submitted to the Commission within 36 months of Commission approval
of the plan.
DATES: Comments are due February 6, 2023 and reply Comments are due
March 6, 2023.
ADDRESSES: Comments, identified by docket number, may be filed in the
following ways. Electronic filing through <a href="https://www.ferc.gov">https://www.ferc.gov</a>, is
preferred.
<bullet> Electronic Filing: Documents must be filed in acceptable
native applications and print-to-PDF, but not in scanned or picture
format.
<bullet> For those unable to file electronically, comments may be
filed by U.S. Postal Service mail or by hand (including courier)
delivery.
[cir] Mail via U.S. Postal Service only: Addressed to: Federal
Energy Regulatory Commission, Office of the Secretary, 888 First Street
NE, Washington, DC 20426.
[cir] For Delivery via Any Other Carrier (including courier):
Deliver to: Federal Energy Regulatory Commission, Office of the
Secretary, 12225 Wilkins Avenue, Rockville, MD 20852.
FOR FURTHER INFORMATION CONTACT:
Eugene Blick (Technical Information), Office of Electric
Reliability, Federal Energy Regulatory Commission, 888 First Street NE,
Washington, DC 20426, (202) 502-8803, <a href="/cdn-cgi/l/email-protection#12576775777c773c507e7b717952747760713c757d64"><span class="__cf_email__" data-cfemail="91d4e4f6f4fff4bfd3fdf8f2fad1f7f4e3f2bff6fee7">[email protected]</span></a>.
Alan J. Rukin (Legal Information), Office of the General Counsel,
Federal Energy Regulatory Commission, 888 First Street NE, Washington,
DC 20426, (202) 502-8502, <a href="/cdn-cgi/l/email-protection#5e1f323f30700c2b3537301e383b2c3d70393128"><span class="__cf_email__" data-cfemail="da9bb6bbb4f488afb1b3b49abcbfa8b9f4bdb5ac">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Table of Contents
Paragraph
Nos.
I. Introduction............................................ 1
II. Background............................................. 10
A. Legal Authority..................................... 10
B. Reliability Impacts of IBR Technologies............. 12
C. Actions To Address the Reliability Impact of IBR 17
Technologies..........................................
III. The Need for Reform................................... 24
A. Recent Events Show IBR-Related Adverse Reliability 24
Impacts on the Bulk-Power System......................
B. Reliability Standards Do Not Adequately Address IBR 27
Reliability Risks.....................................
1. Data Sharing.................................... 27
2. IBR and IBR-DER Data and Model Validation....... 33
[[Page 74542]]
3. IBR and IBR-DER Planning and Operational Studies 47
4. IBR Performance................................. 54
IV. Proposed Directives.................................... 68
A. IBR and IBR-DER Data Sharing........................ 76
B. IBR and IBR-DER Data and Model Validation........... 82
C. IBR and IBR-DER Planning and Operational Studies.... 87
1. Planning Studies................................ 88
2. Operational Studies............................. 89
D. IBR Performance Requirements........................ 90
1. Frequency Ride Through.......................... 93
2. Voltage Ride Through............................ 94
3. Post-Disturbance IBR Ramp Rate Interactions..... 96
4. Phase Lock Loop Synchronization................. 97
V. Information Collection Statement........................ 98
VI. Environmental Assessment............................... 101
VII. Regulatory Flexibility Act Certification.............. 102
VIII. Comment Procedures................................... 104
IX. Document Availability.................................. 108
I. Introduction
1. Pursuant to section 215(d)(5) of the Federal Power Act (FPA),\1\
the Commission proposes to direct NERC, the Commission-certified ERO,
to submit new or modified Reliability Standards that address concerns
pertaining to the impacts of IBRs \2\ on the reliable operation \3\ of
the Bulk-Power System.\4\ The Commission proposes to direct NERC to
develop new or modified Reliability Standards addressing four
reliability gaps pertaining to IBRs: (1) data sharing; (2) model
validation; (3) planning and operational studies; and (4) performance
requirements.
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\1\ 16 U.S.C. 824o(d)(5); 18 CFR 39.5(f).
\2\ This notice of proposed rulemaking (NOPR) uses the term IBR
generally to include all generation resources that connect to the
electric power system using power electronic devices that change
direct current (DC) power produced by a resource to alternating
current (AC) power compatible with distribution and transmission
grids. IBRs may refer to solar photovoltaic (PV), wind, fuel cell,
and battery storage resources.
\3\ The FPA defines reliable operation as operating the elements
of the Bulk-Power System within equipment and electric system
thermal, voltage, and stability limits so that instability,
uncontrolled separation, or cascading failures of such system will
not occur as a result of a sudden disturbance, including a
cybersecurity incident, or unanticipated failure of system elements.
16 U.S.C. 824o(a)(4); see also 18 CFR 39.1.
\4\ The Bulk-Power System is defined in the FPA as facilities
and control systems necessary for operating an interconnected
electric energy transmission network (or any portion thereof), and
electric energy from generating facilities needed to maintain
transmission system reliability. The term does not include
facilities used in the local distribution of electric energy. 16
U.S.C. 824o(a)(1); see also 18 CFR 39.1.
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2. We take this action in view of the rapid change in the
generation resource mix currently underway on the Bulk-Power System,
including the addition of an ``unprecedented proportion of
nonsynchronous resources'' \5\ projected over the next decade,
including many resources that employ inverters and converters \6\ to
provide energy to the Bulk-Power System. According to NERC, the rapid
integration of IBRs is ``the most significant driver of grid
transformation'' on the Bulk-Power System.\7\ While IBRs provide many
benefits, they also present new considerations for transmission
planning and operation of the Bulk-Power System.
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\5\ NERC, 2020 Long Term Reliability Assessment Report, 9 (Dec.
2020), <a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf</a> (2020 LTRA
Report).
\6\ An inverter is a power electronic device that inverts DC
power to AC sinusoidal power through solid state switches. A
converter is a power electronic device that converts AC sinusoidal
power to DC power through solid state switches. Consistent with
NERC's terminology, this order uses the term ``inverter'' to refer
to generating facilities that use power electronic inversion and
conversion. NERC, Inverter-Based Resource Performance and Analysis
Technical Workshop, 29 (Feb. 2019), <a href="https://www.nerc.com/comm/PC/IRPTF%20Workshops/IRPTF_Workshop_Presentations.pdf">https://www.nerc.com/comm/PC/IRPTF%20Workshops/IRPTF_Workshop_Presentations.pdf</a>.
\7\ NERC, Inverter-Based Resource Strategy: Ensuring Reliability
of the Bulk Power System with Increased Levels of BPS-Connected
IBRs, 1 (Sept. 2022), <a href="https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf">https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf</a> (NERC IBR Strategy).
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3. IBRs can produce real and reactive power like synchronous
generators, but IBRs do not react to disturbances on the Bulk-Power
System in the same way. For example, synchronous resources that are not
connected to a fault will automatically ride through \8\ a disturbance
because they are synchronized (i.e., connected at identical speeds) to
the electric power system and physically linked to support the system
voltage or frequency during voltage or frequency fluctuations by
continuing to produce real and reactive power. In contrast, IBRs are
not directly synchronized to the electric power system and must be
programmed to support the electric power system and to ride through a
disturbance. The operational characteristics of IBRs coupled with their
equipment settings may cause them to reduce power output, whether by
tripping offline \9\ or ceasing operation without tripping offline
(known as momentary cessation),\10\ individually or in the aggregate in
response to response to a single fault on a transmission or sub-
transmission system. Such occurrences may exacerbate system
disturbances and have a material impact on the reliable operation of
the Bulk-Power System.
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\8\ See Standardization of Generator Interconnection Agreements
& Procs., Order No. 2003, 68 FR 49846 (Aug. 19, 2003), 104 FERC ]
61,103, at P 562 n.88, (2003) (defining ride through as ``a
Generating Facility staying connected to and synchronized with the
Transmission System during system disturbances within a range of
over- and under-frequency[/voltage] conditions, in accordance with
Good Utility Practice.'').
\9\ Tripping offline is a mode of operation during which part of
or the entire IBR disconnects from the Bulk-Power System and/or
distribution system and therefore cannot supply real and reactive
power.
\10\ Momentary cessation is a mode of operation during which the
inverter remains electrically connected to the Bulk-Power System,
but the inverter does not inject current during low or high voltage
conditions outside the continuous operating range. As a result,
there is no current injection from the inverter and therefore no
active or reactive current (and no active or reactive power). NERC,
Reliability Guideline: Bulk-Power System-Connected Inverter-Based
Resource Performance, 11 (Sept. 2018), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf</a> (IBR Performance
Guideline).
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4. The mandatory and enforceable Reliability Standards were
developed to apply to the generation resources prevalent at the time
that the standards were developed and adopted--nearly exclusively
synchronous generation resources--and ensure the reliable operation of
the Bulk-Power System. As a result, the Reliability Standards may
[[Page 74543]]
not account for the material technological differences between the
response of synchronous generation resources and that of IBRs to the
same disturbances on the Bulk-Power System.\11\ Illustratively, at
least 12 events on the Bulk-Power System \12\ have demonstrated common
mode failures of IBRs regardless of their size or voltage connection,
acting unexpectedly and adversely in response to normally cleared
transmission line faults on the Bulk-Power System.\13\ Further,
simulations indicate that IBR momentary cessation occurring in the
aggregate can lead to instability, system-wide uncontrolled separation,
and voltage collapse.\14\
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\11\ See, e.g., NERC, 2013 Long-Term Reliability Assessment, 22
(Dec. 2013), <a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf</a> (2013 LTRA
Report) (finding that reliably integrating high levels of variable
resources into the Bulk-Power System would require ``significant
changes to traditional methods used for system planning and
operation,'' including requiring ``new tools and practices,
including potential enhancements to . . . Reliability Standards or
guidelines to maintain [Bulk-Power System] reliability.'').
\12\ The 12 events report an average of approximately 1,000 MW
of IBRs entering into momentary cessation or tripping in the
aggregate. The 12 Bulk-Power System events are: (1) the Blue Cut
Fire (August 16, 2016); (2) the Canyon 2 Fire (October 9, 2017); (3)
Angeles Forest (April 20, 2018); (4) Palmdale Roost (May 11, 2018);
(5) San Fernando (July 7, 2020); (6) the first Odessa, Texas event
(May 9, 2021); (7) the second Odessa, Texas event (June 26, 2021);
(8) Victorville (June 24, 2021); (9) Tumbleweed (July 4, 2021); (10)
Windhub (July 28, 2021); (11) Lytle Creek (August 26, 2021), and
(12) Panhandle Wind Disturbance (March 22, 2022).
\13\ The Bulk-Power System's sensing devices usually respond
slowly, and therefore, are likely underreporting the size of the IBR
generation loss during disturbances. See, e.g., NERC and Western
Electricity Coordinating Council (WECC), 900 MW Fault Induced Solar
Photovoltaic Resource Interruption Disturbance Report, 1 n.6 (Feb.
2018), <a href="https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf">https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf</a> (Canyon 2 Fire Event Report) (explaining that MW
loss values are based on supervisory control and data acquisition
(SCADA), which does not capture momentary cessation). NERC only
tracks ``Category 1'' events, which are unexpected outages of three
or more bulk electric system facilities, including interruptions of
IBRs aggregated to a 500 MW threshold (Category 1aii and Category
1i). NERC, ERO Event Analysis Process--Version 4.0, 2 (Dec. 2019),
<a href="https://www.nerc.com/pa/rrm/ea/ERO_EAP_Documents%20DL/ERO_EAP_v4.0_final.pdf">https://www.nerc.com/pa/rrm/ea/ERO_EAP_Documents%20DL/ERO_EAP_v4.0_final.pdf</a>.
\14\ See NERC, Resource Loss Protection Criteria Assessment
Whitepaper, (Feb. 2018), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf</a> (Resource Loss Protection Whitepaper)
(demonstrating the impacts of momentary cessation risks to Bulk-
Power System reliability through simulations).
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5. We preliminarily find that the Reliability Standards may not
provide Bulk-Power System planners or operators with the tools
necessary to plan for and reliably integrate IBRs into the Bulk-Power
System. Further, we preliminarily find that the Reliability Standards
may not provide Bulk-Power System planners or operators with the tools
necessary to plan for IBR-DERs connected to the distribution system
that, when acting in the aggregate, can have a material impact on the
reliable operation of the Bulk-Power System. Additionally, we
preliminary find that the Reliability Standards do not delineate all of
the performance requirements that are unique to IBRs and are necessary
to ensure that IBRs operate in a predictable and reliable manner. We
propose to act to ensure the continued reliable operation of the Bulk-
Power System in response to current, and in anticipation of greater,
IBR penetration onto the Bulk-Power System. We therefore propose,
pursuant to section 215(d)(5) of the FPA and Sec. 39.5(f) of the
Commission's regulations, to direct NERC to develop new or modified
Reliability Standards that address the following specific matters for
IBRs: \15\
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\15\ Various NERC reports do not always differentiate between
IBRs based on type, or between those subject to Reliability
Standards and those located on the distribution system. Where
necessary to qualify our proposed directives, however, we
differentiate between IBRs registered with NERC and therefore
subject to the Reliability Standards because they fall within the
bulk electric system definition (registered IBRs) from those
connected directly to the Bulk-Power System but not registered with
NERC and therefore not subject to the Reliability Standards
(unregistered IBRs), and those connected to the distribution system
(IBR-DER). NERC's Commission-approved bulk electric system
definition is a subset of the Bulk-Power System and defines the
scope of the Reliability Standards and the entities subject to NERC
compliance. Revisions to Electric Reliability Org. Definition of
Bulk Elec. Sys. & Rules of Proc., Order No. 773, 78 FR 804 (Jan. 4,
2013), 141 FERC ] 61,236 (2012) order on reh'g, Order No. 773-A, 78
FR 29209 (May 17, 2013), 143 FERC ] 61,053 (2013) rev'd sub nom.
People of the State of N.Y. v. FERC, 783 F.3d 946 (2d Cir. 2015);
NERC, Glossary of Terms Used in NERC Reliability Standards, 5-7
(Mar. 29, 2022), <a href="https://www.nerc.com/pa/Stand/Glossary%20of%20Terms/Glossary_of_Terms.pdf">https://www.nerc.com/pa/Stand/Glossary%20of%20Terms/Glossary_of_Terms.pdf</a> (NERC Glossary).
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<bullet> IBR Data Sharing: The Reliability Standards should ensure
that NERC registered entities,\16\ such as planning coordinators and
reliability coordinators, have the necessary data to predict the
behavior of all IBRs, including unregistered IBRs and IBR-DERs, and
their impact on the reliable operation of the Bulk-Power System. To
achieve this, the Reliability Standards should ensure that generator
owners, transmission owners, and distribution providers are required to
share validated modeling, planning, operations, and disturbance
monitoring data for IBRs with planning coordinators, transmission
planners, reliability coordinators, transmission operators, and
balancing authorities.
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\16\ NERC identifies and registers Bulk-Power System users,
owners, and operators who are responsible for performing specified
reliability functions to which requirements of mandatory Reliability
Standards are applicable. See NERC Rules of Procedure, Section 500
(Organization Registration and Certification).
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<bullet> IBR Model Validation: The Reliability Standards should
ensure that IBR models are comprehensive, validated, and updated in a
timely manner, so that they can adequately predict the behavior of all
IBRs, including unregistered IBRs and IBR-DERs, and their impacts on
the reliable operation of the Bulk-Power System.
<bullet> IBR Planning and Operational Studies: The Reliability
Standards should ensure that validated IBR models are included in
planning and operational studies to assess the reliability impacts on
Bulk-Power System performance by registered IBRs and unregistered IBRs,
both individually and in the aggregate, as well as IBR-DERs in the
aggregate. The Reliability Standards should ensure that planning and
operational studies assess the impacts of all IBRs within and across
planning and operational boundaries for normal operations and
contingency event conditions.
<bullet> IBR Performance Requirements: The Reliability Standards
should ensure that registered IBRs provide frequency and voltage
support during frequency and voltage excursions in a manner necessary
to contribute toward the overall system needs for essential reliability
services.\17\ The Reliability Standards should establish clear and
reliable technical limits and capabilities for registered IBRs to
ensure that all registered IBRs are operated in a predictable and
reliable manner during: (1) normal operations; and (2) contingency
event conditions. The Reliability Standards should require that the
engineering and operational aspects of registered IBRs necessary to
contribute toward the overall system needs for essential reliability
services include registered IBR post-disturbance ramp rates and phase-
locked loop synchronization.
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\17\ See, e.g., NERC, A Concept Paper on Essential Reliability
Services that Characterizes Bulk Power System Reliability, vi (Oct.
2014), <a href="https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf">https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf</a> (Essential Reliability Services Concept
Paper) (listing the essential reliability services necessary to
maintain Bulk-Power System reliability).
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6. In proposing to direct that NERC develop one or more new
Reliability
[[Page 74544]]
Standards or modify currently effective Reliability Standards to
address the gaps identified in this rulemaking, we are not proposing
specific requirements. Instead, we identify concerns that we believe
the Reliability Standards should address. In its petition accompanying
any new or modified Reliability Standards, NERC should explain how the
new or modified Reliability Standards address the Commission's
concerns.\18\ We invite comments on these concerns and whether there
are other concerns related to planning for and integrating IBRs that
the Commission should direct NERC to address in this or a future
proceeding.
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\18\ See, e.g., Mandatory Reliability Standards for the Bulk-
Power Sys., Order No. 693, 72 FR 16416 (Apr. 4, 2007), 118 FERC ]
61,218, at PP 186, 297, order on reh'g, Order No. 693-A, 72 FR 40717
(July 25, 2007), 120 FERC ] 61,053 (2007) (``where the Final Rule
identifies a concern and offers a specific approach to address the
concern, we will consider an equivalent alternative approach
provided that the ERO demonstrates that the alternative will address
the Commission's underlying concern or goal as efficiently and
effectively as the Commission's proposal'').
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7. We propose to direct NERC to submit a compliance filing within
90 days of the effective date of the final rule in this proceeding.
That compliance filing shall include a detailed, comprehensive
standards development and implementation plan explaining how NERC will
prioritize the development and implementation of new or modified
Reliability Standards. In its compliance filing, NERC should explain
how it is prioritizing its IBR Reliability Standard projects to meet
the directives in the final rule, taking into account the risk posed to
the reliability of the Bulk-Power System, standard development projects
already underway, resource constraints, and other factors if necessary.
8. We seek comment on the proposal to direct NERC to use a
staggered approach that would result in NERC submitting new or modified
Reliability Standards in three stages: (1) new or modified Reliability
Standards including directives related to registered IBR failures to
ride through frequency and voltage variations during normally cleared
Bulk-Power System faults shall be filed with the Commission within 12
months of Commission approval of the plan; (2) new or modified
Reliability Standards addressing the interconnected directives related
to registered IBR, unregistered IBR, and IBR-DER data sharing,
registered IBR disturbance monitoring data sharing, registered IBR,
unregistered IBR, and IBR-DER data and model validation, and registered
IBR, unregistered IBR, and IBR-DER planning and operational studies
shall be filed with the Commission within 24 months of Commission
approval of the plan; and (3) new or modified Reliability Standards
including the remaining directives for post-disturbance ramp rates and
phase-locked loop synchronization shall be filed with the Commission
within 36 months of Commission approval of the plan. We believe this
staggered approach to standard development may be necessary based on
the scope of work anticipated and that specific target dates will
provide a valuable tool and incentive to NERC to timely address the
directives in the final rule. This proposal strikes a reasonable
balance between the need to timely implement identified improvements to
the Reliability Standards that will further Bulk-Power System
reliability and the need for NERC to develop modifications with
appropriate stakeholder input using its open stakeholder process.
9. In view of the rapid growth of IBRs connected to the Bulk-Power
System, we are issuing this NOPR concurrently with a separate order in
Docket No. RD22-4-000 directing NERC to address the registration of
owners and operators of unregistered IBRs that may have a material
impact on the reliable operation of the Bulk-Power System.\19\ That
order addresses the registration of unregistered IBRs that individually
fall outside of the bulk electric system definition, are connected
directly to the Bulk-Power System, and that in the aggregate have a
material impact on the reliable operation of the Bulk-Power System.
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\19\ See Registration of Inverter-based Resources, 181 FERC ]
61,124 (2022).
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II. Background
A. Legal Authority
10. Section 215 of the FPA provides that the Commission may certify
an ERO, the purpose of which is to establish and enforce Reliability
Standards, which are subject to Commission review and approval.
Reliability Standards may be enforced by the ERO, subject to Commission
oversight, or by the Commission independently.\20\ Pursuant to section
215 of the FPA, the Commission established a process to select and
certify an ERO,\21\ and subsequently certified NERC as the ERO.\22\
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\20\ 16 U.S.C. 824o(e).
\21\ Rules Concerning Certification of the Elec. Reliability
Org. & Procs. for the Establishment, Approval, & Enf't of Elec.
Reliability Standards, Order No. 672, 71 FR 8662 (Feb. 17, 2006),
114 FERC ] 61,104, order on reh'g, Order No. 672-A, 71 FR 19814
(Apr. 18, 2006), 114 FERC ] 61,328 (2006).
\22\ N. Am. Elec. Reliability Corp., 116 FERC ] 61,062, order on
reh'g and compliance, 117 FERC ] 61,126 (2006), aff'd sub nom.
Alcoa, Inc. v. FERC, 564 F.3d 1342 (DC Cir. 2009).
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11. The Commission has the authority pursuant to section 215(d)(5)
of the FPA and consistent with Sec. 39.5(f) of the Commission's
regulations, upon its own motion or upon complaint, to order the ERO to
submit to the Commission a proposed Reliability Standard or a
modification to a Reliability Standard that addresses a specific matter
if the Commission considers such a new or modified Reliability Standard
appropriate to carry out section 215 of the FPA.\23\ Further, pursuant
to Sec. 39.5(g) of the Commission's regulations, when ordering the ERO
to submit to the Commission a proposed or modified Reliability Standard
that addresses a specific matter, the Commission may order a deadline
by which the ERO must submit such Reliability Standard.\24\
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\23\ 16 U.S.C. 824o(d)(5); 18 CFR 39.5(f).
\24\ 18 CFR 39.5(g).
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B. Reliability Impacts of IBR Technologies
12. Until recently, the Bulk-Power System generation fleet was
composed almost exclusively of synchronous generation resources \25\
that convert mechanical energy into electric energy through
electromagnetic induction. By virtue of their large rotating elements,
these synchronous generation resources inherently resist changes in
system frequency due to the kinetic energy in their rotating
components, providing time for other governor controls (when properly
configured) to maintain supply and load balance. Similarly, synchronous
generation resources can provide voltage support during voltage
disturbances.
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\25\ The Reliability Standards use both terms ``generation
resources'' and ``generation facilities'' to define sources of
electric power on the transmission system. In this NOPR, we use the
terms ``generation resources'' and ``generation facilities''
interchangeably.
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13. In contrast, IBRs do not use electromagnetic induction from
machinery that is directly synchronized to the Bulk-Power System.
Instead, IBRs predominantly use grid-following inverters, which rely on
sensed information from the grid (e.g., a voltage waveform) in order to
produce the desired AC real and reactive power
[[Page 74545]]
output.\26\ IBRs can track grid state parameters (e.g., voltage angle)
on the order of milli-seconds and react nearly instantaneously to
changing grid conditions. Some IBRs, however, are not configured or
programmed to support grid voltage and frequency and, as a result, will
reduce power,\27\ exhibit momentary cessation, or trip in response to
variations in system voltage or frequency.\28\ In other words, under
certain conditions some IBRs cease to provide power to the Bulk-Power
System due to how they are configured and programmed even though some
models and simulations predict that IBRs maintain real power output and
provide voltage and frequency support consistent with Reliability
Standard PRC-024-2 (Generator Frequency and Voltage Protective Relay
Settings).
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\26\ See, e.g., NERC, 2021 Long Term Reliability Assessment
Report, 6 (Dec. 2021), <a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf</a> (2021 LTRA Report)
(``IBRs respond to disturbances and dynamic conditions based on
programmed logic and inverter controls, not mechanical
characteristics.''); see also generally, Denholm et al., National
Renewable Energy Laboratory, Inertia and the Power Grid: A Guide
Without the Spin, NREL/TP-6120-73856, v (2020), <a href="https://www.nrel.gov/docs/fy20osti/73856.pdf">https://www.nrel.gov/docs/fy20osti/73856.pdf</a>.
\27\ NERC and WECC, San Fernando Disturbance, 2 (Nov. 2020),
<a href="https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf</a> (San Fernando Disturbance
Report).
\28\ See Essential Reliability Servs. & the Evolving Bulk-Power
Sys. Primary Frequency Response, Order No. 842, 83 FR 9636 (Mar. 6,
2018), 162 FERC ] 61,128 , at P 19 (2018) (describing NERC's comment
that increased IBR deployment alongside retirement of synchronous
generation resources has contributed to the decline in primary
frequency response); see also NERC, Fast Frequency Response Concepts
and Bulk Power System Reliability Needs, 5 (Mar. 2020), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf</a> (Fast Frequency Response White Paper) (explaining that as the
instantaneous penetration of IBRs with little or no inertia
continues to increase, system rate of change of frequency after a
loss of generation will increase and the time available to deliver
frequency responsive reserves will shorten, and illustrating the
steeper rate of change of frequency and the importance of speed of
response).
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14. IBRs are also more dispersed across the Bulk-Power System
compared to synchronous generation resources, and both localized and
interconnection-wide IBR issues must be identified, studied, and
mitigated to preserve Bulk-Power System reliability. Although IBRs are
typically smaller-megawatt (MW) facilities, they are at greater risk
than synchronous generation resources of being lost (i.e., ceasing to
provide power to the Bulk-Power System) in the aggregate in response to
a single fault on the transmission or sub-transmission systems. Such
response can occur when individual IBR controls and equipment
protection settings are not configured to ride through system
disturbances.\29\ Thus, the impact of IBRs is not restricted by the
size of a single facility or an individual balancing authority area,
but rather by the number of IBRs or percent of generation made up by
IBRs within an interconnection. In areas of high IBR saturation, this
type of aggregate response may have an impact much greater than the
most severe single contingency (i.e., the traditional worst-case N-1
contingency) \30\ of a balancing authority area, potentially adversely
affecting other balancing authority areas across an
interconnection.\31\ Unless IBRs are configured and programmed to ride
through normally cleared transmission faults, the potential impact of
losing IBRs individually or in the aggregate will continue to increase
as IBRs are added to the Bulk-Power System and make up an increasing
proportion of the resource mix.
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\29\ See, e.g., Canyon 2 Fire Event Report at 19 (finding
momentary cessation as a major cause for the loss of IBRs when
voltages rose above 1.1 per unit or decreased below 0.9 per unit).
\30\ The most severe single contingency, or the N-1 contingency,
generally refers to the concept that a system must be able to
withstand an unexpected failure or outage of a single system
component and maintain reliable service at all times. See, e.g.,
NERC Glossary at 17 (defining ``most severe single contingency'').
\31\ See, e.g., San Fernando Disturbance Report at vi (stating
that ``[t]his event, as with past events, involved a significant
number of solar PV resources reducing power output (either due to
momentary cessation or inverter tripping) as a result of normally-
cleared [Bulk-Power System] faults. The widespread nature of power
reduction across many facilities poses risks to [Bulk-Power System]
performance and reliability.'').
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15. Further, simulations conducted by the NERC Resource
Subcommittee demonstrate that the risks to Bulk-Power System
reliability posed by momentary cessation are greater than any of the
IBR disturbances NERC has documented as being experienced thus far.
These simulations indicate the potential for: (1) normally-cleared,
three-phase faults at certain locations in the Western Interconnection
that could result in upwards of 9,000 MW of solar PV IBRs entering
momentary cessation across a large geographic region; (2) transient
instability caused by excessive transfer of inter-area power flows
during and after momentary cessation; and (3) a drop in frequency that
falls below the first stage of under frequency load shedding in WECC,
traditionally studied as the loss of the two Palo Verde nuclear units
in Arizona (approximately 2,600 MW).\32\ These simulation results
indicate that IBR momentary cessation occurring in the aggregate can
lead to instability, system-wide uncontrolled separation, and voltage
collapse.
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\32\ Resource Loss Protection Whitepaper at 1-2, key findings 4,
7, 8.
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16. Although IBRs present risks that Bulk-Power System planners and
operators must account for, IBRs also present new opportunities to
support the grid and respond to abnormal grid conditions.\33\ When
appropriately programmed, IBRs can operate during greater frequency
deviations (i.e., a wider frequency range) than synchronous generation
resources.\34\ This operational flexibility, and the ability of IBRs to
perform with precision and speed, offers increased Bulk-Power System
performance capabilities and controls that could mitigate disturbances
on the Bulk-Power System. For Bulk-Power System operators to harness
the unique performance and control capabilities of IBRs, these
resources must be properly configured and programmed to support grid
voltage and frequency during normal and abnormal grid conditions and be
accurately modeled and represented in transmission planning and
operations models.
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\33\ See, e.g., IBR Performance Guideline at vii (finding that
the power electronics aspects of IBRs ``present new opportunities in
terms of grid control and response to abnormal grid conditions.'').
\34\ See, e.g., Fast Frequency Response White Paper at 11.
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C. Actions To Address the Reliability Impact of IBR Technologies
17. NERC has begun to address some of the reliability risk posed by
IBRs. Specifically, since the first documented disturbance event on the
Bulk-Power System demonstrating common mode failures of IBRs in 2016,
NERC has: (1) published seven reports on 12 disturbance events; \35\
(2) issued two
[[Page 74546]]
NERC Alerts addressing the loss of solar PV IBRs; \36\ (3) issued three
reliability guidelines; \37\ (4) formed the IBR performance task force
(IRPTF) \38\ and a system planning impacts of distributed energy
resources working group (SPIDERWG); (5) issued various technical
reports regarding IBR data collection and performance; \39\ and (6)
issued an IBR strategy document.\40\ The NERC materials (e.g.,
guidelines, whitepapers, reports, alerts, etc.) cited in this NOPR are
also listed in Appendix A as a reference. Appendix A will not appear in
the Federal Register. Appendix A will be available separately on the
Commission's website.\41\
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\35\ The seven reports on the 12 disturbances are:
(1) NERC, 1,200 MW Fault Induced Solar Photovoltaic Resource
Interruption Disturbance Report (June 2017), <a href="https://www.nerc.com/pa/rrm/ea/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_Interruption_Final.pdf">https://www.nerc.com/pa/rrm/ea/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_Interruption_Final.pdf</a> (Blue Cut Fire Event Report) (covering the Blue Cut Fire event
(August 16, 2016));
(2) Canyon 2 Fire Event Report (covering the Canyon 2 Fire event
(October 9, 2017));
(3) NERC and WECC, April and May 2018 Fault Induced Solar
Photovoltaic Resource Interruption Disturbances Report (Jan. 2019),
(Angeles Forest and Palmdale Roost Events Report), <a href="https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf</a> (Angeles Forest and
Palmdale Roost Events Report) (covering the Angeles Forest (April
20, 2018) and Palmdale Roost (May 11, 2018) events);
(4) San Fernando Disturbance Report (covering the San Fernando
event (July 7, 2020));
(5) NERC and Texas RE, Odessa Disturbance (Sept. 2021), <a href="https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf</a>
(Odessa Disturbance Report) (covering events in Odessa, Texas on May
9, 2021 and June 26, 2021);
(6) NERC and WECC, Multiple Solar PV Disturbances in CAISO
(April 2022), <a href="https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf</a> (2021 Solar PV
Disturbances Report) (covering four events: Victorville (June 24,
2021); Tumbleweed (July 4, 2021); Windhub (July 28, 2021); and Lytle
Creek (August 26, 2021)); and
(7) NERC and Texas RE, March 2022 Panhandle Wind Disturbance
Report (August 2022), <a href="https://www.nerc.com/pa/rrm/ea/Documents/Panhandle_Wind_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/Panhandle_Wind_Disturbance_Report.pdf</a> (Panhandle Report) (covering
the Texas Panhandle event (March 22, 2022)).
\36\ NERC, Industry Recommendation: Loss of Solar Resources
during Transmission Disturbances due to Inverter Settings (June
2017), <a href="https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC%20Alert%20Loss%20of%20Solar%20Resources%20during%20Transmission%20Disturbance.pdf">https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC%20Alert%20Loss%20of%20Solar%20Resources%20during%20Transmission%20Disturbance.pdf</a> (Loss of Solar Resources Alert I); NERC, Industry
Recommendation Loss of Solar Resources during Transmission
Disturbances due to Inverter Settings--II (May 2018), <a href="https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC_Alert_Loss_of_Solar_Resources_during_Transmission_Disturbance-II_2018.pdf">https://www.nerc.com/pa/rrm/bpsa/Alerts%20DL/NERC_Alert_Loss_of_Solar_Resources_during_Transmission_Disturbance-II_2018.pdf</a> (Loss of Solar Resources Alert II).
\37\ See IBR Performance Guideline; NERC, Reliability Guideline:
Improvements to Interconnection Requirements for BPS-Connected
Inverter-Based Resources (Sept. 2019), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_IBR_Interconnection_Requirements_Improvements.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_IBR_Interconnection_Requirements_Improvements.pdf</a> (IBR Interconnection Requirements Guideline); NERC, Reliability
Guideline: Performance, Modeling, and Simulations of Bulk-Power
System-Connected Battery Energy Storage Systems and Hybrid Power
Plants (Mar. 2021), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_BESS_Hybrid_Performance_Modeling_Studies_.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_BESS_Hybrid_Performance_Modeling_Studies_.pdf</a>
(BESS Performance Modeling Guideline).
\38\ The task force later became the IBR Performance Working
Group in October 2020, and most recently became the IBR Performance
Subcommittee in March 2022. For consistency, this NOPR uses
``IRPTF'' to refer to all three iterations.
\39\ See, e.g., NERC, Technical Report, Bulk-Power System-
Connected Inverter-Based Resource Modeling and Studies, (May 2020),
<a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf</a> (Modeling and Studies Report);
NERC and WECC, WECC Base Case Review: Inverter-Based Resources (Aug.
2020), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf</a> (Western Interconnection (WI) Base
Case IBR Review).
\40\ NERC IBR Strategy, (July 2021), <a href="https://www.nerc.com/FilingsOrders/us/NERC%20Filings%20to%20FERC%20DL/2022-2024%20RSDP%20FERC%20Filing.pdf">https://www.nerc.com/FilingsOrders/us/NERC%20Filings%20to%20FERC%20DL/2022-2024%20RSDP%20FERC%20Filing.pdf</a>.
\41\ Federal Energy Regulatory Commission, Table of Cited NERC
IBR Resources (RM22-12-000), <a href="https://www.ferc.gov/media/table-cited-nerc-ibr-resources-rm22-12-000">https://www.ferc.gov/media/table-cited-nerc-ibr-resources-rm22-12-000</a>.
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18. The only NERC actions that required a response from entities
are the two NERC alerts addressing the loss of solar PV IBRs (both
alerts were level 2 alerts, ``Recommendation to Industry'').\42\ These
NERC level 2 alerts recommended specific voluntary action to be taken
by registered IBRs and required that the registered IBRs provide
responsive information to NERC. While unregistered IBRs could also
voluntarily take the specific actions set out in the level 2 alert,
there was no reporting requirement for unregistered IBRs due to NERC's
authority to require reporting responses only from registered IBRs.
NERC issued these alerts to assess the scope of and recommend
performance actions to address registered IBR reliability risks to the
Bulk-Power System. NERC issued its first alert in 2017 after the Blue
Cut Fire Event to collect data to assess the extent of the condition
and to provide recommended performance improvements for existing and
newly interconnecting solar PV IBRs connected to the Bulk-Power
System.\43\ NERC issued its second alert in 2018 after the Canyon 2
Fire event to recommend performance improvements including eliminating
momentary cessation for registered IBRs already in operation.\44\
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\42\ NERC uses level 2 alerts to recommend specific actions to
be taken by registered entities (i.e., ``Recommendation to
Industry''). A response from recipients, as defined in the alert, is
required. NERC, About Alerts (2022), <a href="https://www.nerc.com/pa/rrm/bpsa/Pages/About-Alerts.aspx">https://www.nerc.com/pa/rrm/bpsa/Pages/About-Alerts.aspx</a>. NERC also uses level 1 alerts (i.e.,
``Industry Advisory'') to advise registered entities of issues or
potential problems, which does not require a response. In addition,
NERC uses level 3 alerts (i.e., ``Essential Action'') to identify
actions that registered entities are required to take because they
are deemed to be ``essential'' to reliability.
\43\ Loss of Solar Resources Alert I at 4-6 (noting that
although the alert pertains directly to registered IBRs, the ``same
potential susceptibility to frequency and voltage perturbations
during transmission faults exist for all utility grade, and perhaps
some larger commercial grade solar installations, regardless of the
interconnection voltage.'').
\44\ Loss of Solar Resources Alert II at 1-5 (finding again that
``[a]lthough this NERC Alert pertains specifically to [bulk electric
system] solar PV resources, the same characteristics may exist for
non-[bulk electric system] solar PV resources connected to the
[Bulk-Power System] regardless of installed generating capacity or
interconnection voltage.'' (footnote omitted)).
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19. NERC formed the IRPTF in response to the findings and
recommendations of the Blue Cut Fire Event Report in order to explore
the performance characteristics of Bulk-Power System connected IBRs.
The IRPTF is composed of subject matter experts and representatives
from a variety of companies, registered entities, and trades groups
familiar with IBR issues and reliability risks. Among other activities,
the IRPTF has developed a variety of whitepapers and reliability
guidelines.\45\ For example, the Modeling and Studies Report documented
the failure of industry to mitigate IBR-related momentary cessation,
tripping, and modeling issues.\46\ In March 2020, the IRPTF issued a
white paper evaluating the applicability of certain Reliability
Standards to IBRs and identifying seven Reliability Standards with
potential gaps or areas for improvement.\47\
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\45\ See NERC, Reliability Guidelines, Security Guidelines,
Technical Reference Documents, and White Papers, (2022), <a href="https://www.nerc.com/comm/Pages/Reliability-and-Security-Guidelines.aspx">https://www.nerc.com/comm/Pages/Reliability-and-Security-Guidelines.aspx</a>
(providing links to all IRPTF resources).
\46\ Modeling and Studies Report at iv-v, 1-8.
\47\ Specifically, the white paper identified Reliability
Standards: (1) FAC-001-3; (2) FAC-002-2; (3) MOD-026-1; (4) MOD-027-
1; (5) PRC-002-2; (6) TPL-001-4/-5; and (7) VAR-002-4.1. NERC, IRPTF
Review of NERC Reliability Standards White Paper, 1, (Mar. 2020),
<a href="https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf">https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf</a>
(Reliability Standards Review White Paper).
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20. NERC formed the SPIDERWG to, among other things, identify
potential gaps in the Reliability Standards and address IBR-DER
modeling and performance.\48\ For example, on December 30, 2019, the
SPIDERWG submitted a standard authorization request proposing to
address gaps in Reliability Standard MOD-032-1 (Data for Power System
Modeling and Analysis) requirements for data collection for the
purposes of modeling and interconnection-wide planning case models.\49\
Based on the extensive record created by the IRPTF and SPIDERWG on the
need for the Reliability Standards to address IBR impacts on the
reliable operation of the Bulk-Power System, NERC initiated several
standards projects \50\ to consider discrete changes
[[Page 74547]]
to the Facilities Design, Connections and Maintenance (FAC), Modeling,
Data and Analysis (MOD), Protection and Control (PRC), Transmission
Planning (TPL), and Voltage and Reactive Control (VAR) Reliability
Standards.\51\
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\48\ NERC, System Planning Impacts from DER Working Group
(SPIDERWG), (2022) <a href="https://www.nerc.com/comm/RSTC/Pages/SPIDERWG.aspx">https://www.nerc.com/comm/RSTC/Pages/SPIDERWG.aspx</a>.
\49\ NERC, Standard Authorization Request, Project 2020-01
Modifications to MOD-032-1 (Dec. 2021), <a href="https://www.nerc.com/pa/Stand/Project202202ModificationstoTPL00151andMOD0321DL/2022-02_MOD-032%20SAR%20SPIDERWG_020122.pdf">https://www.nerc.com/pa/Stand/Project202202ModificationstoTPL00151andMOD0321DL/2022-02_MOD-032%20SAR%20SPIDERWG_020122.pdf</a>.
\50\ See NERC Rules of Procedure, app. 3A (Standard Processes
Manual) (providing the process for developing, modifying,
withdrawing, or retiring a Reliability Standard. One of the first
steps in the process is initiating a standards authorization
request, which is a form used to document the scope and benefit of a
proposed standards drafting project).
\51\ See NERC, Informational Filing of Reliability Standards
Development Plan 2022-2024, Docket No. RM05-17-000, et al., attach.
A (Reliability Standards Development Plan 2022-2024), 3-4 (filed
Nov. 30, 2021) (NERC 2022-2024 Reliability Standards Development
Plan). However, several of these projects lack IBR-specific
considerations or reporting requirements (e.g., MOD-026-1, MOD-027-
1, and PRC-002-2), lack requirements to assess IBR aggregate impacts
(e.g., VAR-002-4.1), or are identified in the Reliability Standards
development plan as ``low priority.'' See also NERC, IBR Strategy,
<a href="https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf">https://www.nerc.com/comm/Documents/NERC_IBR_Strategy.pdf</a> (providing
a milestone plan of proposed SARs, reliability guidelines, and
whitepapers).
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21. Other NERC technical committees have also met to review
recommendations of the Odessa Disturbance Report, including
recommendations for Reliability Standards addressing, among other IBR-
related issues: (1) ride through; (2) performance validation; (3)
analysis and reporting for abnormal inverter options; (4) monitoring;
and (5) inverter-specific performance requirements.\52\
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\52\ NERC, Odessa Disturbance Follow-up White Paper, 3-8 (Oct.
2021), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf</a> (Odessa Disturbance
White Paper).
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22. Concurrently with this NOPR, we are also approving revisions to
Reliability Standards FAC-001-3 (Facility Interconnection Requirements)
and FAC-002-3 (Facility Interconnection Studies).\53\ The revisions
were responsive to IRPTF recommendations to modify the standards to:
(1) clarify the registered entity responsible for determining which
facility changes require study (a ``qualified change''); and (2)
clarify that a generator owner should notify affected registered
entities before making a qualified change. As a part of its petition,
NERC included examples of qualified changes specific to IBRs, such as a
change in inverter settings that may result in a difference in
frequency or voltage support.\54\
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\53\ See North American Electric Reliability Corporation, 181
FERC ] 61,126 (2022).
\54\ NERC, Petition for Approval of Proposed Reliability
Standards FAC-001-4 and FAC-002-4, Docket No. RD22-5-000, at 9-13
(filed June 14, 2022) (including examples of IBR-related qualified
changes: (1) a change of 10% or more in nameplate capacity of the
IBR; and (2) a change in the IBR's control settings that cause a
difference in (a) frequency or voltage support or (b) when the IBR
stops injecting power into the transmission system).
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23. In addition to NERC's efforts, there are voluntary industry
standards and manufacturer certification efforts related to IBRs in
place or underway, such as the Institute of Electrical and Electronics
Engineers (IEEE) standard 2800-2020 \55\ for transmission connected
IBRs, and IEEE 1547-2018 \56\ and Underwriters Laboratory (UL) standard
UL 1741 \57\ for IBR-DERs. These efforts may enhance the operating
performance and control capabilities of IBRs; however, these efforts
remain at relatively early stages, do not apply to all relevant IBRs,
and require adoption by state or other regulatory authorities.\58\ The
proposed directives to NERC to develop new or modify existing
Reliability Standards are intended to complement existing voluntary
efforts underway and are not intended to supersede or interfere with
these efforts.
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\55\ IEEE Standard for Interconnection and Interoperability of
Inverter-Based Resources (IBR) Interconnecting with Associated
Transmission Electric Power Systems (IEEE 2800-2022), <a href="https://standards.ieee.org/ieee/2800/10453/">https://standards.ieee.org/ieee/2800/10453/</a> (explaining that 2800-2020
standard establishes ``[u]niform technical minimum requirements for
the interconnection, capability, and lifetime performance of [IBRs]
interconnecting with transmission and sub-transmission systems . . .
[and includes] . . . performance requirements for reliable
integration of [IBRs] into the [B]ulk [P]ower [S]ystem.'').
\56\ IEEE, Interconnection and Interoperability of Distributed
Energy Resources with Associated Electric Power Systems Interfaces
(IEEE 1547-2018), <a href="https://sagroups.ieee.org/scc21/standards/1547rev/">https://sagroups.ieee.org/scc21/standards/1547rev/</a>
. The IEEE 1547-2018 and more recent 2020 amendment of this standard
enhance operating performance and control capabilities of IBR-DER.
For example, future IBR-DER will be equipped with the capability to
ride through voltage and frequency fluctuation in support of the
reliable operation of Bulk-Power System.
\57\ UL Standard 1741 Edition 3, Inverters, Converters,
Controllers and Interconnection System Equipment for Use With
Distributed Energy Resources Scope, <a href="https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=40673">https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=40673</a>.
\58\ While the IEEE-2800-2020 was approved in September 2022, it
has yet to be adopted by any transmission entity. For IEEE-1547,
states have made varied progress in adopting the IBR-DER. Adoption
of IEEE Standard 1547<SUP>TM</SUP>-2018. Further, IEEE 1547-2018
inverter products are not expected to be generally available to the
market until April 2023. IEEE, IEEE Standard for Interconnection and
Interoperability of Distributed Energy Resources with Associated
Electric Power Systems Interfaces, <a href="https://sagroups.ieee.org/scc21/standards/1547rev/">https://sagroups.ieee.org/scc21/standards/1547rev/</a>.
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III. The Need for Reform
A. Recent Events Show IBR-Related Adverse Reliability Impacts on the
Bulk-Power System
24. A number of events have demonstrated the challenges to
transmission planning and operations of the Bulk-Power System posed by
gaps in the Reliability Standards specific to IBRs in the areas of: (1)
IBR data sharing; (2) IBR model validation; (3) IBR planning and
operational studies; and (4) registered IBR performance requirements.
25. The first documented large-scale disturbance event related to
IBRs occurred in August of 2016 during the Blue Cut Fire event in
California. Until this event, the potential for IBRs to affect the
reliability of the Bulk-Power System by tripping or momentarily ceasing
during faults was unknown.\59\ A NERC/WECC joint task force determined
that a single 500 kV line-to-line fault caused the widespread loss of
1,200 MW of primarily solar PV IBRs, which adversely affected the
balance of generation and load needed to maintain Interconnection
frequency near a nominal value of 60 Hz.\60\ The task force found that
the solar PV generation loss was primarily due to the unexpected
tripping and unanticipated momentary cessation of IBRs.\61\ The report
indicated that planning studies incorrectly predicted that IBRs would
ride through the disturbance and would provide power during the event.
Once aware of the potential for IBRs to trip or enter momentary
cessation in response to faults, Southern California Edison (SoCal
Edison) and the California Independent System Operator Corporation
(CAISO) reviewed the supervisory control and data acquisition (SCADA)
data from SoCal Edison energy management system and discovered that
this was not an isolated incident.\62\
---------------------------------------------------------------------------
\59\ Blue Cut Fire Event Report at 15-16.
\60\ Id. at 1.
\61\ Id. at 9 (identifying momentary cessation as a major cause
for the loss of IBRs when voltages rose above 1.1 per unit or
decreased below 0.9 per unit. NERC also identified IBRs that tripped
due to erroneous frequency calculations and concluded that a more
accurate representation of the system frequency measurement should
be used for inverter controls, and a minimum delay for frequency
detection and/or filtering should be implemented. NERC reported that
the Blue Cut fire IBR erroneous frequency calculation issue was
successfully mitigated).
\62\ SoCal Edison/CAISO identified seven other instances of
solar PV IBRs either tripping or entering momentary cessation. Id.
at 3. See also Modeling and Studies Report at 3-4 (explaining that
SoCal Edison and CAISO attempted to collect updated generation
dynamic models from generator owners and discussing their challenges
in obtaining the data).
---------------------------------------------------------------------------
26. Despite NERC's efforts to date, events involving registered
IBRs, unregistered IBRs, and IBR-DERs have continued to occur in areas
of the country with large penetrations of IBRs.\63\ Noting the
continuing need to address IBR concerns, the NERC Board of Trustees has
stated that ``the risk of unreliable performance from [Bulk-
[[Page 74548]]
Power System]-connected inverter-based resources remains high'' and
that NERC and the Regional Entities ``remain[] concerned with [Bulk-
Power System] performance, modeling, planning and study approaches, and
is urging immediate industry action.'' \64\ As the resource mix trends
towards higher penetrations of IBRs, the need to reliably integrate
these resources into the Bulk-Power System is expected to grow.\65\
Although groups such as IEEE and entities like CAISO have attempted to
address these issues at the state, local, or individual entity level,
the continuing events across the Bulk-Power System and the risks that
they pose to its reliable operation underscore the need for mandatory
Reliability Standards to address these issues on a nationwide basis.
---------------------------------------------------------------------------
\63\ Since the first Blue Cut Fire event in August 2016, there
have been at least 11 additional events throughout the last six
years, including the most recently reported event in March 2022.
NERC, Major Event Analysis Reports, <a href="https://www.nerc.com/pa/rrm/ea/Pages/Major-Event-Reports.aspx">https://www.nerc.com/pa/rrm/ea/Pages/Major-Event-Reports.aspx</a>, see supra note 12 (listing the IBR-
related events).
\64\ NERC, Members Representatives Committee Agenda Package, 2
(May 2022), <a href="https://www.nerc.com/gov/bot/Agenda%20highlights%20and%20Mintues%202013/Policy-Input-Package-May-2022-PUBLIC-POSTING.pdf">https://www.nerc.com/gov/bot/Agenda%20highlights%20and%20Mintues%202013/Policy-Input-Package-May-2022-PUBLIC-POSTING.pdf</a>.
\65\ See Reliability Standards Review White Paper at 1 (finding
that the ``electric industry is still experiencing unprecedented
growth in the use of inverters as part of the bulk power system and
growth is possibly creating new circumstances where current
standards may not be sufficiently addressing those needs.'').
---------------------------------------------------------------------------
B. Reliability Standards Do Not Adequately Address IBR Reliability
Risks
1. Data Sharing
27. The Reliability Standards do not ensure that planning
coordinators, transmission planners, reliability coordinators,
transmission operators, and balancing authorities receive accurate and
complete data on the location, capacity, telemetry, steady-state,
dynamic and short circuit modeling information, control settings, ramp
rates, equipment status, disturbance analysis data, and other
information about IBRs (collectively, IBR data). IBR data is necessary
to properly plan, operate, and analyze performance on the Bulk-Power
System.\66\ As evidenced by the Modeling and Studies Report, the
Reliability Standards do not ensure that IBR generator owners and
operators consistently share IBR data, as at least a portion of the
information that is shared is inaccurate or incomplete.\67\ For
example, in the Modeling and Studies Report, the IRPTF found that
Reliability Standard MOD-032-1 ``does not prescribe the details that
the modeling requirements must cover; rather, the standard requirements
leave the level of detail and data formats up to each TP [transmission
planner] and PC [planning coordinator] to define.'' Further, the IRPTF
found that many of the dynamic models submitted in response to an IBR-
related NERC Alert ``that were intended to represent the existing
settings and controls currently installed in the field either did not
match the data provided by the [generator owner] for actual settings or
did not meet the [transmission planner and planning coordinator]
requirements for model performance, (i.e., incorrect models used,
incorrect parameters, or inability of model to initialize).'' \68\
---------------------------------------------------------------------------
\66\ Loss of Solar Resources Alert II at 7-8 (describing
examples of planning and operational IBR data) and Odessa
Disturbance Report at 20-21; see generally WI Base Case IBR Review,
NERC, Reliability Guideline: DER Data Collection for Modeling in
Transmission Planning Studies, (Sept. 2020) (IBR-DER Data Collection
Guideline).
\67\ See Modeling and Studies Report at 33 (finding that a
``significant number of inverter-based resources, particularly solar
PV resources, have submitted [root-mean-square] positive sequence
dynamic models for the interconnection-wide case creation process
(i.e., MOD-032-1) that do not accurately represent the control
settings programmed into the inverters installed in the field.'').
See also Western Interconnection (WI) Base Case IBR Review at 27
(describing comments from transmission planners and planning
coordinators relaying concerns regarding generator owners' lack of
timely responses (or any response in many cases) regarding modeling-
related issues on the use of generic manufacturer-supplied data, and
failure to update models consistent with Reliability Standard MOD-
032-1).
\68\ Modeling and Studies Report at 33.
---------------------------------------------------------------------------
28. Without accurate and complete IBR data, planning coordinators,
transmission planners, reliability coordinators, transmission
operators, and balancing authorities are not able to develop accurate
system models that account for the behavior of IBRs on their system,
nor are they able to facilitate the analysis of Bulk-Power System
disturbances.\69\
---------------------------------------------------------------------------
\69\ E.g., Commission Staff, Distributed Energy Resources
Technical Considerations for the Bulk Power System Staff Report,
Docket No. AD18-10-000 (filed Feb. 15, 2018) (Commission Staff IBR-
DER Reliability Report); Modeling and Studies Report at 33
(recommending that generator owners, for both registered and
unregistered IBRs, ``should submit updated models to the
[transmission planners and planning coordinators] as quickly as
possible to accurately reflect the large disturbance behavior of
[Bulk-Power System]-connected solar PV resources in the
interconnection-wide base cases used for planning assessments.'').
---------------------------------------------------------------------------
a. Registered IBR Data Sharing
29. The Reliability Standards do not ensure that transmission
planners and operators receive modeling data and parameters from all
bulk electric system generation resources necessary to create and
maintain valid individual registered IBR models used to perform steady-
state, dynamic, and short circuit studies. While Reliability Standard
MOD-032-1(Data for Power System Modeling and Analysis), Requirement R2,
requires generator owners to submit modeling data and parameters to
their transmission planners and planning coordinators, it does not
require generator owners to submit registered IBR-specific modeling
data and parameters, such as control settings for momentary cessation
and ramp rates, necessary for modeling steady state and dynamic
registered IBR performance for purposes of planning the Bulk-Power
System.\70\ Similarly, Reliability Standard TOP-003-4 (Operational
Reliability Data) does not require generator owners to submit
registered IBR-specific modeling data and parameters transmission
operators or balancing authorities, such as control settings for
momentary cessation and ramp rates, necessary for modeling steady state
and dynamic registered IBR performance for purposes of operating the
Bulk-Power System.
---------------------------------------------------------------------------
\70\ See Modeling and Studies Report at 35 (stating that
Reliability Standard MOD-032-1 ``does not prescribe the details that
the modeling requirements must cover; rather, the standard
requirements leave the level of detail and data formats up to each
[transmission planner] and [planning coordinator] to define.''
(footnote omitted)).
---------------------------------------------------------------------------
b. Unregistered IBR and IBR-DER Data Sharing
30. The Reliability Standards do not ensure that transmission
planners and operators receive modeling data and parameters regarding
unregistered IBRs and IBR-DERs that, individually or in the aggregate,
are capable of adversely affecting the reliable operation of the Bulk-
Power System. As shown by various reports and guidelines,\71\ planners
and operators do not currently have the data to accurately model the
behavior of unregistered IBRs as well as IBR-DERs in the aggregate for
steady-state, dynamic, and short circuit studies.
---------------------------------------------------------------------------
\71\ See, e.g., Commission Staff IBR-DER Reliability Report at
11-13 (explaining that absent adequate data, many Bulk-Power System
models and operating tools will not fully represent the effects of
IBR-DERs in aggregate. The report also noted the lack of a formal
process to provide static IBR-DER data to Bulk-Power System
operators and planners as well as the limited visibility that
operators and planners have into IBR-DER telemetry data); see also
IBR-DER Data Collection Guideline at 2 (recommending that
transmission planners and planning coordinators update their data
reporting requirements for Reliability Standard MOD-032-1,
Requirement R1 to explicitly describe the requirements for aggregate
IBR-DER data in a manner that is clear and consistent with their
modeling practices. The guideline also recommended that transmission
planners and planning coordinators establish modeling data
requirements for steady-state IBR-DERs in aggregate and coordinate
with their distribution providers to develop these requirements).
---------------------------------------------------------------------------
c. Disturbance Monitoring Data Sharing
31. The Reliability Standards do not ensure that transmission
planners and operators receive disturbance
[[Page 74549]]
monitoring data regarding all generation resources capable of having a
material impact on the reliable operation of the Bulk-Power System,
including IBRs, to adequately assess disturbance events (e.g., a fault
on the line, a generator tripped off-line) and their behavior during
those events. Without adequate monitoring capability, the disturbance
analysis data for a system event is not comprehensive enough to
effectively determine the causes of the system event.\72\ Further, the
absence of adequate monitoring capability leads to the potential for
unreliable operation of resources due to the inability to effectively
gather disturbance analysis data and develop mitigation strategies for
abnormal resource performance during disturbance events.
---------------------------------------------------------------------------
\72\ 2021 Solar PV Disturbances Report at 13. The report
explains that the ``analysis team had significant difficulty
gathering useful information for root cause analysis at multiple
facilities . . . [and] this led to an abnormally large number of
`unknown' causes of power reduction for the plants analyzed.''
---------------------------------------------------------------------------
32. Limitations on the availability of event data have hampered
efforts by NERC and industry to determine the causes of various events
since 2016, explained in more detail below. In many instances, data was
limited and disturbance monitoring equipment was absent because
registered IBRs generally do not fall within the thresholds of the
current Reliability Standard PRC-002-2 (Disturbance Monitoring and
Reporting Requirements) Attachment 1 methodology requirements for
equipment installation given that they often interconnect at lower
voltages and are typically smaller compared to synchronous
generators.\73\ While Reliability Standard PRC-002-2 requires the
installation of disturbance monitoring equipment at certain key nodes
(e.g., stability limited interfaces), and such limited placements were
adequate to provide the data necessary to analyze major system events
in the past, they are not sufficient to analyze the distributed system
events that have become more common since 2016.\74\
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\73\ Reliability Standard PRC-002-2, Attachment 1 includes a
methodology for selecting which buses require sequence of events
recording and fault recording data--IBRs do not meet the threshold
for this methodology.
\74\ See, e.g., Angeles Forest and Palmdale Roost Events Report
at 23 (explaining that the lack of data visibility and poor data
quality continue to be a concern for comprehensive event analysis
after large Bulk-Power System disturbances, as well as how the
quality of event reporting is negatively affected by data
acquisition resolution issues as a lack of high speed data captured
at the IBR controller hinders a complete analysis of IBR behavior in
response to Bulk-Power System fault events); San Fernando
Disturbance Report at 7 (explaining that many facilities have data
archiving systems that only record, store, and retrieve information
with a one-minute resolution (or a five-minute resolution in some
cases) and that no facilities recorded electrical quantities with
sufficient resolution to observe their on-fault behavior, limiting
the ability to perform a more detailed analysis of the event.);
Odessa Disturbance Report at 11 (indicating some improved monitoring
data, but noting the monitoring capability at solar PV facilities is
not comprehensive enough to effectively perform root cause analysis
and is leading to unreliable operation of these resources due to the
inability to effectively develop mitigations for abnormal
performance). See generally Odessa Disturbance White Paper; NERC,
San Fernando Disturbance Follow-Up NERC Inverter-Based Resource
Performance Working Group White Paper, (June 2021), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/IRPWG_San_Fernando_Disturbance_Follow-Up_Paper%20">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/IRPWG_San_Fernando_Disturbance_Follow-Up_Paper%20</a>(003).pdf (San
Fernando Disturbance White Paper).
---------------------------------------------------------------------------
2. IBR and IBR-DER Data and Model Validation
33. IBR-specific modeling data and parameters are necessary to
ensure that the registered entities responsible for planning and
operating the Bulk-Power System can validate both the individual
registered IBR and unregistered IBR data as well as IBR-DER data in the
aggregate by comparing the provided data and resulting models with
actual performance and behavior.\75\ Therefore, even if the Reliability
Standards did ensure planning coordinators, transmission planners,
reliability coordinators, transmission operators, and balancing
authorities receive registered IBR modeling data from registered IBR
generator owners and operators, the Reliability Standards would still
need to include unregistered IBR modeling data and parameters and IBR-
DER aggregate modeling data and parameters to ensure reliability. The
bulk electric system definition, which delineates the entities required
to comply with the Reliability Standards, does not include unregistered
IBRs or IBR-DERs. Therefore, the current Reliability Standards do not
address the provision of either unregistered IBR or IBR-DER aggregate
modeling data and parameters. Further, the Reliability Standards do not
include IBR-specific modeling data and parameters (e.g., performance
and control settings). As a result, the planning coordinators,
transmission planners, reliability coordinators, transmission
operators, and balancing authorities need to coordinate with: (1)
registered IBR generator owners and operators, (2) transmission owners
that have unregistered IBRs connected to their systems, (3) and the
distribution providers that have IBR-DERs to obtain IBR specific
modeling data and parameters so that the transmission planners and
operators can validate the accuracy of such data to create meaningful
models of steady-state and dynamic registered IBR, unregistered IBR,
and aggregate IBR-DER performance.\76\
---------------------------------------------------------------------------
\75\ Modeling and Studies Report at 37 (recommending revising
Reliability Standards MOD-026-1 (Verification of Models and Data for
Generator Excitation Control System or Plant Volt/Var Control
Functions) and MOD-027-1 (Verification of Models and Data for
Turbine/Governor and Load Control or Active Power/Frequency Control
Functions) to ``ensure that large disturbance behavior of [IBRs] is
verified.''). In addition, the task force recommended that
transmission planners and planning coordinators ``should be required
to verify the appropriateness of all dynamic model parameters to
ensure suitability of these parameters to match actual performance
for all operating conditions.'' Id. See also WI Base Case IBR Review
at v (recommending that IBR owners ensure that all data fields are
reported correctly, that transmission planners and planning
coordinators ``should verify that the data fields are submitted
correctly,'' and that the Regional Entity ``should ensure that data
quality checks are being performed on all incoming data from
[transmission planners] and [planning coordinators] for their
areas.'').
\76\ Static or steady-state models represent electrical
component state variables as constant with respect to the time
variable of the simulation. Steady-state models are used to
represent a single snapshot of balanced system conditions as
observed during normal Bulk-Power System operations and serve as a
basis of subsequent time-variant technical studies. Dynamic models
represent electrical component state variables that vary with time
depending on the course of the simulation. Dynamic models are built
upon steady-state models and may be validated to ensure they
adequately reflect actual historic performance and/or field-testing
data. Dynamic models are used by the industry to evaluate resource
(i.e., generation and load) performance during simulated events and
event investigations.
---------------------------------------------------------------------------
34. System planners and operators need accurate planning,
operational, and interconnection-wide models to ensure reliable
operation of the system. Planners and operators use electrical
component models to build the generation, transmission, and
distribution facility models that form the planning and operational
area models, and these area models are combined with the models of
their neighboring footprints to form the interconnection-wide models.
Each of the planning, operational, and interconnection-wide models
consist separately of steady state, dynamic, and short circuit models.
35. Without planning, operational, and interconnection-wide models
that accurately reflect the resource (e.g., generators and loads)
behavior in steady state and dynamic conditions; otherwise, planners
and operators are unable to adequately predict resources' behaviors,
including momentary cessation from both individual and aggregate
registered IBRs and unregistered IBRs, as well as IBR-DERs in the
aggregate and subsequent impacts
[[Page 74550]]
on the Bulk-Power System.\77\ Accordingly, to be able to adequately
predict resources' behaviors, planners and operators must validate and
update resource models by comparing the provided data and resulting
models against actual operational behavior.\78\ When accuracy and
validation of models are combined, these planning, operational, and
interconnection-wide models enable planners and operators to perform
valid planning, operational, and interconnection-wide studies.
---------------------------------------------------------------------------
\77\ See IBR Interconnection Requirements Guideline at 24
(stating that a systemic modeling issue was uncovered regarding the
accuracy of the inverter-based resource dynamic models submitted in
the interconnection-wide base cases following the issuance of the
NERC Alert related to the Canyon 2 Fire disturbance).
\78\ See Modeling and Studies Report at 35 (explaining that
assessments on the accuracy or reasonableness of modeling parameter
values are not typically performed and standardized validity testing
for dynamic models of newer generation inverter-based resources is
not readily available to planners; therefore, contributing to
inaccuracies in the interconnection-wide base cases).
---------------------------------------------------------------------------
a. Approved Component Models
36. The starting points for an accurate planning, operational, and
interconnection-wide model are the steady state, dynamic, and short
circuit models of the elements that make up generation, transmission,
and distribution facilities. To this end, NERC has worked with its
stakeholders to develop, validate, and maintain a library of
standardized approved component models (e.g., generator elements) and
parameters for powerflow and dynamic cases.\79\ NERC's approved
component model list is a collection of generic industry steady-state
and dynamic models (e.g., excitor, governor, load, etc.) that when
combined accurately reflect the steady-state and dynamic performance of
a resource.\80\ Despite these efforts, some resource owners still
provide modeling data that is based on a proprietary model rather than
an approved industry-vetted model.\81\ The use of proprietary models in
interconnection-wide models can be problematic because their internal
model components cannot be viewed or modified, and thus produce outputs
that cannot be explained or verified.\82\ Without using approved
generator models that accurately reflect the generator behavior in
steady state and dynamic conditions, planners and operators are unable
to adequately predict IBR behavior and subsequent impact on the Bulk-
Power System.\83\ The Reliability Standards do not require the use of
NERC's approved component models; instead, models are referred to
generally in Reliability Standard MOD-032-1 Attachment 1.\84\
---------------------------------------------------------------------------
\79\ NERC Libraries of Standardized Powerflow Parameters and
Standardized Dynamics Models version 1 (Oct. 2015), <a href="https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf">https://www.nerc.com/comm/PC/Model%20Validation%20Working%20Group%20MVWG%202013/NERC%20Standardized%20Component%20Model%20Manual.pdf</a> (NERC
Standardized Powerflow Parameters and Dynamics Models).
\80\ The models are specific to the power flow software. NERC
communicates the approved models list by issuing modeling
notifications and guidelines. NERC annually assesses the
interconnection-wide case quality and publishes a report to help
entities responsible for complying with Reliability Standard MOD-
032-1 to resolve model issues and improve the cases. See NERC,
Reliability Assessment and Performance Analysis Department Modeling
Assessments, <a href="https://www.nerc.com/pa/RAPA/ModelAssessment/Pages/default.aspx">https://www.nerc.com/pa/RAPA/ModelAssessment/Pages/default.aspx</a>.
\81\ NERC Standardized Powerflow Parameters and Dynamics Models
at 1 (explaining that ``[s]ome of the model structures have
information that is considered to be proprietary or confidential,
which impedes the free flow of information necessary for
interconnection[hyphen]wide power system analysis and model
validation.'') See also NERC, Events Analysis Modeling Notification
Recommended Practices for Modeling Momentary Cessation Initial
Distribution, n.4 (Feb. 2018), <a href="https://www.nerc.com/comm/PC/NERCModelingNotifications/Modeling_Notification_-_Modeling_Momentary_Cessation_-_2018-02-27.pdf">https://www.nerc.com/comm/PC/NERCModelingNotifications/Modeling_Notification_-_Modeling_Momentary_Cessation_-_2018-02-27.pdf</a> (explaining that more
detailed vendor-specific models may be used for local planning
studies; however, they are generally not allowed or recommended for
the interconnection-wide cases).
\82\ See, e.g., Electric Power Research Institute, Model User
Guide for Generic Renewable Energy System, 2 (June 2015), <a href="https://www.epri.com/research/products/000000003002006525">https://www.epri.com/research/products/000000003002006525</a> (explaining that
the ``models presented here were developed primarily for the purpose
of general public use and benefit and to eliminate the long standing
issues around many vendor-specific models being proprietary and thus
neither publicly available nor easily disseminated among the many
stakeholders. Furthermore, using multiple user-defined non-standard
models within large interconnection studies, in many cases,
presented huge challenges and problems with effectively and
efficiently running the simulations.'').
\83\ NERC Standardized Powerflow Parameters and Dynamics Models
(explaining that there is a growing need for accurate
interconnection[hyphen]wide powerflow and dynamics simulations that
analyze phenomena such as: frequency response, inter-area
oscillations, and interactions between the growing numbers of wide-
area control and protections systems).
\84\ Reliability Standard MOD-032-1, Attachment 1 (explaining
that if a user-written model(s) is submitted in place of a generic
or library model, it must include the characteristics of the model,
including block diagrams, values and names for all model parameters,
and a list of all state variables).
---------------------------------------------------------------------------
b. IBR Plant Dynamic Model Performance Verification
37. Once each generator provides a NERC and industry-approved
generator model, the model performance must be verified by real-world
data.\85\ The currently effective Reliability Standards MOD-026-1 \86\
and MOD-027-1 \87\ require the generator owner to verify models and
data for specific components of synchronous resources (e.g., generator
excitation control systems, plant volt/var control functions, turbine/
governor and load controls, and active power/frequency controls), but
they do not require a generator owner to provide verified models and
data for IBR-specific controls (e.g., power plant central controller
functions and protection system settings). Further, the Reliability
Standards neither require verified dynamic models from the transmission
owner for unregistered IBRs nor require verified IBR-DER dynamic models
in the aggregate from distribution providers.
---------------------------------------------------------------------------
\85\ NERC Standardized Powerflow Parameters and Dynamics Models
at 1 (explaining that the NERC Modeling Working Group was tasked to
develop, validate, and maintain a library of standardized component
models and parameters for powerflow and dynamics cases. The
standardized models in these libraries have documentation describing
their model structure, parameters, and operation. This information
has been vetted by the industry and thus deemed appropriate for
widespread use in interconnection[hyphen]wide analysis.).
\86\ Reliability Standard MOD-026-1 (Verification of Models and
Data for Generator Excitation Control System or Plant Volt/Var
Control Functions).
\87\ Reliability Standard MOD-027-1 (Verification of Models and
Data for Turbine/Governor and Load Control or Active Power/Frequency
Control Functions).
---------------------------------------------------------------------------
38. Transmission planners and operators need dynamic models (i.e.,
models of equipment that reflect the equipment's behavior during
changing grid conditions and disturbances) that accurately represent
the dynamic performance of all generation resources, including
momentary cessation when applicable. As discussed in several NERC
analyses,\88\ current IBR dynamic models do not accurately represent
disturbance behavior due to model deficiencies and because certain key
parameters that govern large disturbance response are incorrect; thus,
planners are not able to rely on these IBR dynamic models. Unless IBR
models are verified to ensure that the models accurately reflect IBR
performance during testing or actual events, planners' and system
operators' unverified models may indicate that the IBRs will behave
reliably when studied in planning and operational analyses, even if
ride through operation modes such as momentary cessation persist in
actual operations, as observed during
[[Page 74551]]
the Blue Cut Fire and Canyon 2 Fire events. Additionally, the 2017 NERC
DER Report explained that accurate IBR-DER dynamic models are needed
where ``[IBR-]DERs are expected to have a significant impact on the
modeling results.'' \89\
---------------------------------------------------------------------------
\88\ WI Base Case IBR Review at 18, 25 (finding that the models
are not parameterized with as-built settings and that verification
of dynamic models is not capturing errors); see also Modeling and
Studies Report at 34 (finding that a significant number of generator
owners submitted data in response to the Loss of Solar Resources
Alert II ``indicating that they could eliminate the use of
[momentary cessation] for existing resources; however, either no
model of proposed changes was provided, or the provided model did
not meet [transmission planner] and [planning coordinator]
requirements for model performance.'').
\89\ NERC, Distributed Energy Resources: Connection Modeling and
Reliability Considerations, 7 (Feb. 2017), <a href="https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf">https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf</a> (NERC DER Report) at 6
(explaining that ``[a]n assessment of the expected impact will have
to be scenario-based, and the time horizon of interest may vary
between study types. For long-term planning studies, expected DER
deployment levels looking 5-10 years ahead may reasonably be
considered.''). The NERC DER Report also noted that modeling the
modern Bulk-Power System ``with a detailed representation of a large
number of [IBR-]DER[s] and distribution feeders can increase the
complexity, dimension, and handling of the system models beyond
practical limits in terms of computational time, operability, and
data availability.'' Id.
---------------------------------------------------------------------------
39. NERC has issued multiple recommendations for: (1) generator
owners of IBRs to ensure that their dynamic models accurately represent
the behavior of the actual installed equipment; \90\ (2) transmission
planners and planning coordinators to work with generator owners and
operators of IBRs connected to their system to ensure that the dynamic
models correctly represent the large disturbance behavior of the actual
installed equipment; \91\ and (3) transmission planners and planning
coordinators to develop updated dynamic models of their systems that
accurately represent momentary cessation and to study the impacts of
IBRs on the Bulk-Power System.\92\
---------------------------------------------------------------------------
\90\ See, e.g., Loss of Solar Resources Alert II at 2
(generators should ``[e]nsure that the dynamic model(s) being used
accurately represent the dynamic performance of the solar
facilities.'' The generator owners should ``update the dynamic
model(s) to accurately represent momentary cessation and provide the
model(s) to the Transmission Planner and Planning Coordinator (to
support . . . Reliability Standard TPL-001-4 studies) and to the
Reliability Coordinator, Transmission Operator, and Balancing
Authority (in accordance with . . . Reliability Standards TOP-003-3
and IRO-010-2).''); see also WI Base Case IBR Review at 18, 25
(recommending that the IBR generator owners update their generic
models as soon as possible).
\91\ See, e.g., Modeling and Studies Report at 33 (recommending
that ``[Generator owners] should submit updated models to the
[transmission planners] and [planning coordinators] as quickly as
possible to accurately reflect the large disturbance behavior of
[Bulk-Power System]-connected solar PV resources in the
interconnection-wide base cases used for planning assessments. This
applies to [bulk electric system] resources as well as non-[bulk
electric system] resources connected to the [Bulk-Power System].'').
NERC further recommended that ``[transmission planners] and
[planning coordinators] should proactively work with all [Bulk-Power
System]-connected solar PV resources connected to their system to
ensure that the dynamic models correctly represent the large
disturbance behavior of the actual installed equipment. [Generator
owners] should verify the dynamic model parameters with actual
equipment and control settings. These activities should occur on a
regular basis.'' Id.
\92\ Id. at 34; see also Loss of Solar Resources Alert II at 3.
---------------------------------------------------------------------------
c. Validating and Updating System Models
40. Transmission planners and operators must validate and update
system models by comparing the provided data and resulting system
models against actual system operational behavior. While Reliability
Standard MOD-033-2 requires data validation of the interconnection-wide
system model,\93\ the Reliability Standards lack clarity as to whether
models of registered IBRs, unregistered IBRs, and IBR-DERs in the
aggregate are required to represent the real-world behavior of the
equipment installed in the field for interconnection-wide disturbances
that have demonstrated common mode failures of IBRs.\94\
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\93\ Reliability Standard MOD-033-2 (Steady State and Dynamic
System Model Validation), Requirements R1, R2.
\94\ NERC annually assesses the interconnection-wide case
quality and publishes a report to help entities responsible for
complying with Reliability Standard MOD-032 to resolve model issues
and improve the cases. As NERC's 2021 Case Quality Metrics
Assessment asserts, currently planners are neither able to develop
accurate system models that account for the IBRs on their system,
nor facilitate the analysis of Bulk-Power System disturbances. See
NERC, Case Quality Metrics Annual Interconnection-wide Model
Assessment, (Oct. 2021), <a href="https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2021_Case_Quality_Metrics_Assessment-FINAL.pdf">https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2021_Case_Quality_Metrics_Assessment-FINAL.pdf</a>.
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41. In addition, Reliability Standard MOD-032-1 lacks clarity on
whether generator owners are required to communicate to planners and
operators if there are any changes to registered IBRs, including
settings, configurations, and ratings. Additionally, transmission
owners are not required to communicate to planners and operators if
there are any changes to unregistered IBRs for modeling, including
settings, configurations, and ratings. Similarly, distribution
providers are not required to communicate to planners and operators if
there are any changes to IBR-DERs in the aggregate for modeling,
including settings, configurations, and ratings. While Reliability
Standards MOD-032-1 and MOD-033-2 have iterative updating and
validation processes, Reliability Standard MOD-032-1 lacks IBR-specific
modeling data and parameters and Reliability Standard MOD-033-2 does
not contemplate the technology-specific performance characteristics of
registered IBRs, unregistered IBRs, and IBR-DERs. As NERC explained in
its petition for approval of the proposed Reliability Standards MOD-
032-1 and MOD-033-2, the lack of generator model verification can
result in ``the use of inaccurate models [that] could result in grid
underinvestment, unsafe operating conditions, and ultimately widespread
power outages.'' \95\
---------------------------------------------------------------------------
\95\ NERC, Petition for Approval of Proposed Reliability
Standards MOD-032-1 and MOD-033-1, Docket No. RD14-5-000, at 2, 9-10
(filed Feb. 25, 2014).
---------------------------------------------------------------------------
42. In the November 2020 San Fernando Disturbance Report, NERC and
WECC found that the previously identified modeling issues in the
interconnection-wide planning base cases and modeling challenges
continued to be an issue.\96\ The San Fernando Disturbance Report again
recommended that generator owners and generator operators take steps to
ensure communication of changes to various settings, topologies, and
ratings to their relevant transmission planner, planning coordinator,
balancing authority, and reliability coordinator.\97\
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\96\ San Fernando Disturbance Report at ix; Odessa Disturbance
Report at 22-28, 29-31.
\97\ San Fernando Disturbance Report at ix.
---------------------------------------------------------------------------
d. Lack of Coordination When Creating and Updating Planning,
Operational, and Interconnection-Wide Models
43. Planners and operators need to coordinate planning,
operational, and interconnection-wide models so that they represent all
generation resources--including registered IBRs, unregistered IBRs,
IBR-DERs in the aggregate and synchronous generation--and load. When
coordinated properly, these sets of models ensure enough detail for
planners and operators to perform valid planning, operational, and
interconnection-wide studies.
44. Reliability Standard MOD-032-1 Requirement R4 requires planning
coordinators to make available models for their planning areas to the
ERO or its designee \98\ to support creation of interconnection-wide
cases.\99\ Two reliability gaps lead to interconnection-wide cases that
do not reflect the large disturbance behavior that NERC identified in
its analyses of IBR disturbance events. The first gap is the use of
incorrect and unvalidated registered IBR, unregistered IBR, and IBR-DER
models (discussed above) that do not accurately represent performance
and behavior of both individual and
[[Page 74552]]
aggregate registered IBRs and unregistered IBRs, as well as IBR-DERs in
the aggregate. Planners and operators incorporate incorrect and
unvalidated IBR models within the footprint of the planner and operator
area models. These registered IBR, unregistered IBR, and IBR-DER model
inaccuracies from the planning and operation area models then propagate
into the interconnection-wide cases.
---------------------------------------------------------------------------
\98\ See Reliability Standard MOD-032-1, Requirement R4.
\99\ In this NOPR, the terms ``interconnection-wide case'' and
``interconnection-wide model'' are interchangeable. Both refer to a
collection of electric power system models and requisite data
developed to represent either a snapshot of the electric power
system at a particular point of time (e.g., year, season) or to
represent the power system at a particular operating condition
(i.e., normal or abnormal).
---------------------------------------------------------------------------
45. Secondly, there is a coordination gap among registered entities
that build and verify interconnection-wide cases. Reliability Standards
MOD-032-1 and MOD-033-2 do not obligate the applicable entities to work
collaboratively to create interconnection-wide cases that accurately
reflect real-world interconnection-wide IBR performance and
behavior.\100\ In the Western Interconnection, for example, a single
MOD-032-1 designee, WECC, collects a set of planning models from the
planning authority and builds an interconnection-wide case on the
behalf of the registered entities. Having a single MOD-032-1 designee
helps in efficiently building an interconnection-wide case. However,
the process does not contain requirements for the MOD-032-1 designee to
coordinate and verify with MOD-033-2 functional entities (e.g., the
system operators) that the interconnection-wide cases reflect real-
world IBR behaviors. For example, the Modeling and Studies Report
indicates that the MOD-032-1 feedback loops are not being used to
correct modeling issues.\101\ Further, NERC's 2020 annual assessment of
interconnection-wide case quality report explains that there is a need
to compare the interconnection-wide models against actual measured
system conditions and encourages planning coordinators to consider
performing the comparison during MOD-033 evaluation, but such a
comparison is not required by a standard.\102\ The Reliability
Standards should ensure registered entities coordinate to build
interconnection-wide cases that reflect the large disturbance behavior
of both individual and aggregate registered IBRs and unregistered IBRs,
as well as IBR-DERs in the aggregate (i.e., tripping offline or
momentary cessation individually or in the aggregate in response to a
single fault on a transmission or sub-transmission system).
---------------------------------------------------------------------------
\100\ Reliability Standard MOD-032-1 is applicable to the
following entities: (1) balancing authority, (2) generator owner,
(3) load serving entity, (4) planning authority/planning
coordinator, (5) resource planner, (6) transmission owner, (7)
transmission planner, and (8) transmission service provider.
\101\ See Modeling and Studies Report at 27 (finding that
``[t]he feedback loops developed in MOD-032-1 are not being used by
[transmission planners] and [planning coordinators] to correct
modeling issues, nor are [transmission planners] and [planning
coordinators] being proactive to address identified issues on a
widespread basis.'').
\102\ NERC, Case Quality Metrics Annual Interconnection-Wide
Model Assessment, vii (Oct. 2020), <a href="https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2020_Case_Quality_Metrics_Assessment-FINAL_postpubs.pdf">https://www.nerc.com/pa/RAPA/ModelAssessment/ModAssessments/2020_Case_Quality_Metrics_Assessment-FINAL_postpubs.pdf</a> (explaining that the report focuses solely on the
case data quality of the individual component models comprising the
base case and that validation of an interconnection-wide case or
overall model performance requires comparison of the cases to actual
measured system conditions and are not included in the report.
Nevertheless, the report does encourage planning coordinators ``to
consider these metrics in their MOD-033 evaluation and to also
include metrics on case fidelity.'').
---------------------------------------------------------------------------
46. NERC and WECC identified the impacts of these two reliability
gaps in the WI Base Case IBR Review. Specifically, NERC and WECC found
that IBR dynamic models used for interconnection-wide planning and
operating studies do not properly represent the behavior of the
equipment installed in the field, as current interconnection-wide cases
contain many inaccurate and unverified IBR models, and many wind and
solar PV IBRs are not represented.\103\
---------------------------------------------------------------------------
\103\ WI Base Case IBR Review at 1-4.
---------------------------------------------------------------------------
3. IBR and IBR-DER Planning and Operational Studies
47. The Reliability Standards do not ensure that planning and
operational studies assess the performance and behavior (e.g., IBRs
tripping or entering momentary cessation individually or in the
aggregate) of both individual and aggregate registered IBRs and
unregistered IBRs, as well as IBR-DERs in the aggregate. Planning and
operational studies must use validated registered IBR, unregistered
IBR, and IBR-DER aggregate modeling and operational data (as discussed
in above Section III.B.1. Data Sharing and Section III.B.2. IBR and
IBR-DER Data and Model Validation) to ensure studies account for the
actual behavior of registered IBRs, unregistered IBRs, and IBR-DERs in
the aggregate. Planning and operational studies must assess the
performance and behavior of individual and aggregate registered IBRs
and unregistered IBRs, as well as IBR-DERs in the aggregate, during
normal and contingency conditions for the reliable operation of the
Bulk-Power System.
a. Planning Studies
48. Transmission planning (TPL) Reliability Standards are intended
to ensure that the transmission system is planned and designed to meet
an appropriate and specific set of reliability criteria. The TPL
Reliability Standards, however, do not require planners to study in
planning assessments the performance and behavior specific to both
individual and aggregate registered IBRs and unregistered IBRs, as well
as IBR-DERs in the aggregate, under normal operations and contingency
event conditions. This reliability gap in planning assessments may lead
to false expectations that system performance requirements are met and
may inadvertently mask potential reliability risks in planning and
operations. NERC's 2021 Battery Storage and Hybrid Plants Guideline
further identifies reliability gaps in planning assessments related to
newer technologies and provides recommendations to address some of the
aforementioned concerns.\104\ Nevertheless, as reliability guidelines
are voluntary, the gap remains.
---------------------------------------------------------------------------
\104\ See BESS Performance Modeling Guideline, ix Recommendation
S1 and S2 (explaining study process enhancements and expansion of
study conditions are needed for both interconnection-wide and annual
planning assessments to ensure that the variability and uncertainty
of renewable energy resources (e.g., registered IBRs, unregistered
IBRs, and IBR-DERs in the aggregate) are reflected in planning
analyses with appropriate dispatch conditions and under stressed
operating conditions. NERC further explained that renewable energy
resources have led to different operating conditions than were
previously used in planning assessments and ``indicates that
developing suitable and reasonable study assumptions will become a
significant challenge for future planning analyses.'').
---------------------------------------------------------------------------
49. Reliability Standard TPL-001-4 (Transmission System Planning
Performance Requirements) requires planning to ensure reliable
operations over a broad spectrum of system conditions and following a
wide range of probable contingencies.\105\ The 2021 Solar PV
Disturbances Report explains that ``many of the reliability issues
observed in real-time [e.g., solar PV resources tripping off line and
momentary cessation] and identified in the numerous disturbance reports
are not being captured in planning studies.'' \106\ The Odessa
Disturbance Report explains that IBR plants are ``abnormally responding
to [Bulk-Power System] disturbance events and ultimately tripping
themselves off-line'' and that these issues are not being
[[Page 74553]]
properly detected by the models and studies conducted during annual
planning assessments.\107\ In addition, the Panhandle Report found that
``many [Bulk-Power System]-connected inverter-based resources (and
distributed energy resources) will significantly reduce active power
for depressed voltages'' that will change grid dynamics and should be
accurately modeled in simulations and studied during planning
assessments.\108\
---------------------------------------------------------------------------
\105\ Reliability Standard TPL-001-5.1 (Transmission System
Planning Performance Requirements) was approved by the Commission to
become effective on July 1, 2023. See N. Am. Elec. Reliability
Corp., Docket No. RD20-8-000 (June 10, 2020) (delegated letter
order) (approving a NERC-proposed erratum to Reliability Standard
TPL-001-5); Transmission Planning Reliability Standard TPL-001-5,
Order No. 867, 85 FR 8155 (Feb. 13, 2020), 170 FERC ] 61,030 (2020)
(approving Reliability Standard TPL-001-5).
\106\ 2021 Solar PV Disturbances Report at 8 and 21.
\107\ Odessa Disturbance Report at 43.
\108\ Panhandle Report at 8.
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50. The NERC DER Report found that many IBR-DERs are generally not
visible to Bulk-Power System planners and stated that Bulk-Power System
plans must account for this lack of visibility.\109\ The report
recommended that IBR-DERs be ``modeled in an aggregated and/or
equivalent way to reflect their dynamic characteristics and steady-
state output.'' \110\ The report also found that planners face a
challenge with respect to forecasting the adoption of IBR-DER types
over long-term planning horizons with ``sufficient locational
granularity for identifying and planning needed [Bulk-Power System]
infrastructure upgrades.'' \111\
---------------------------------------------------------------------------
\109\ NERC DER Report at 3.
\110\ Id. at 9.
\111\ Id. at 35.
---------------------------------------------------------------------------
51. Similarly, in the WI Base Case IBR Review, NERC and WECC
observed that IBR-DERs are not widely included in WECC base cases and
noted that this could pose a ``risk for the creation of a reasonable
starting case for entities neighboring those with notable [IBR-] DER
penetrations.'' \112\ NERC and WECC also observed that planners and
operators do not have enough information about generators (including
IBR information) to develop a complete and accurate base case.\113\
---------------------------------------------------------------------------
\112\ WI Base Case IBR Review at 2.
\113\ Id. at 1-4.
---------------------------------------------------------------------------
b. Operational Studies
52. Operators must perform various operational studies, including
operational planning analyses, real-time monitoring, real-time
assessments and other analyses that include all resources necessary to
adequately assess the performance of the Bulk-Power System for normal
and contingency conditions.\114\ The Reliability Standards do not
require operators to include the performance and behavior of both
individual and aggregate registered IBRs and unregistered IBRs, as well
as IBR-DERs in the aggregate (e.g., IBRs tripping or entering momentary
cessation individually or in the aggregate) in operational studies used
to identify potential system operating limits and interconnection
reliability operating limit exceedances and to identify any potential
reliability risks related to instability, cascading, or uncontrolled
separation. In addition, models of registered IBRs, unregistered IBRs,
as well as models of IBR-DERs in the aggregate are generally not
accurate (as discussed above), which invalidates the operational
studies, as evidenced by numerous Bulk-Power System IBR disturbance
events seen since 2016.\115\ For example, in the FERC, NERC, and
Regional Entity Joint Report on Real-time Assessments, ``[s]everal
participants expressed concern that Contingencies may now change
seasonally because of the decline in system inertia due to the growing
number of Inverter-Based Resources in the generation mix. This placed a
greater onus on the participant to conduct in-depth and up-to-date
studies to ensure all stability Contingencies on its system are
identified.'' \116\
---------------------------------------------------------------------------
\114\ See Reliability Standard TOP-001-5 (Transmission
Operations), Requirements R10, R11, R13; Reliability Standard TOP-
002-4 (Operations Planning), Requirements R1, R4; Reliability
Standard IRO-008-2 (Reliability Coordinator Operational Analyses and
Real-time Assessments), Requirements R1, R4; Reliability Standard
IRO-002-7 (Reliability Coordination--Monitoring and Analysis),
Requirement R5.
\115\ See Modeling and Studies Report at iv (finding that ``Many
of the dynamic models that were supplied by [generator owners] as
part of the NERC Alert process had modeling errors or inaccuracies
and were unusable to the [transmission planner] and [planning
coordinator].''); see also NERC DER Report at vi (expressing that
``Today, the effect of aggregated [IBR-]DER is not fully represented
in [Bulk-Power System] models and operating tools.'').
\116\ FERC, NERC, Regional Entities, Joint Report on Real-time
Assessments, 13-14 (July 2021), <a href="https://www.ferc.gov/media/ferc-and-ero-enterprise-joint-report-real-time-assessments">https://www.ferc.gov/media/ferc-and-ero-enterprise-joint-report-real-time-assessments</a>.
---------------------------------------------------------------------------
53. In the Loss of Solar Resources Alert II, NERC recommended that
reliability coordinators, transmission operators, and balancing
authorities ``[t]rack, retain, and use the updated IBR dynamic model(s)
. . . of existing resource performance that are supplied by the
Generator Owners to perform assessments and system analyses to identify
any potential reliability risks related to instability, cascading, or
uncontrolled separation . . . .'' \117\ In addition, the NERC DER
Report explained that IBR-DERs do not follow a dispatch signal and are
generally not visible to Bulk-Power System operators.\118\ The NERC DER
Report recommended that all components of the Bulk-Power System,
including IBR-DERs, be modeled either directly or in aggregate, with
sufficient fidelity to enable dynamic and steady-state models to
provide meaningful and accurate simulations of actual system
performance.\119\
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\117\ Loss of Solar Resources Alert II at 4-5.
\118\ NERC DER Report at 3; see also IBR Performance Guideline
at 65.
\119\ NERC DER Report at iv, 9.
---------------------------------------------------------------------------
4. IBR Performance
54. Essential reliability services, such as frequency and voltage
support, serve as the basis for reliably operating the Bulk-Power
System. Without the availability of essential reliability services, the
system would experience instability, voltage collapse, or uncontrolled
separation.\120\ NERC's Essential Reliability Services Concept Paper
initially identified two essential reliability services building
blocks--voltage support and frequency support.\121\ Some components of
these services are provided automatically by synchronous generation due
to their physical and mechanical properties. By contrast, IBRs must be
configured and programmed to provide these services, and the
Reliability Standards do not require registered IBRs to provide such
services.
---------------------------------------------------------------------------
\120\ Essential Reliability Services Concept Paper at iii.
\121\ Id.
---------------------------------------------------------------------------
55. The Commission previously revised the pro forma Large Generator
Interconnection Agreement and the pro forma Small Generator
Interconnection Agreement to require newly interconnecting generating
facilities to address certain issues related to essential reliability
services. In Order No. 827, the Commission required all newly
interconnecting non-synchronous generating facilities to provide
dynamic reactive power within the range of 0.95 leading to 0.95 lagging
at the high-side of the generator substation as a condition of
interconnection unless the transmission provider establishes a
different power factor range, eliminating an earlier exemption for wind
generation.\122\ In Order No. 828, the Commission required newly
interconnecting small generating facilities to have the capability to
``ride through abnormal frequency and voltage events and not disconnect
during such events.'' \123\ Finally, in Order No. 842,
[[Page 74554]]
the Commission required newly interconnecting generating facilities
``to install, maintain, and operate equipment capable of providing
primary frequency response as a condition of interconnection.'' \124\
---------------------------------------------------------------------------
\122\ Reactive Power Requirements for Non-Synchronous
Generation, Order No. 827, 81 FR 40793 (June 23, 2016), 155 FERC ]
61,277, at PP 1-2 (2016).
\123\ Requirements for Frequency & Voltage Ride Through
Capability of Small Generating Facilities, Order No. 828, 81 FR
50290 (Aug. 1, 2016), 156 FERC ] 61,062, at P 1 (2016). The
Commission went on to explain that it ``continues to affirm that
this Final Rule is not intended to interfere with state
interconnection procedures or agreements in any way. The pro forma
SGIA applies only to interconnections made subject to a
jurisdictional open access transmission tariff (OATT) for the
purposes of jurisdictional wholesale sales.'' Id. P 12.
\124\ Essential Reliability Servs. & the Evolving Bulk-Power
Sys.--Primary Frequency Response, Order No. 842, 162 FERC ] 61,128
at P 1.
---------------------------------------------------------------------------
a. Frequency Ride Through
56. The Reliability Standards do not account for the difference
between registered IBRs' and synchronous facilities' responses during
normal and contingency conditions. IBR technology is different than
synchronous generation technologies. For instance, IBR ride through
capability must be configured and programmed for IBRs to be able to
ride through frequency disturbances. Synchronous resources will
automatically ride through a disturbance because they are synchronized
(i.e., connected at identical speeds) to the electric power system and
physically linked to support the system frequency during frequency
fluctuations by continuing to produce real and reactive power. The
frequency of an interconnection depends on the instantaneous balance
between load and generation resources to which all resources must
contribute during both normal and contingency conditions. This requires
generation resources to remain connected to the grid and continue to
support grid frequency (i.e., ride through) for either loss of
generation (underfrequency) or loss of load (overfrequency) related
frequency deviations.
57. Reliability Standard PRC-024-3 (Frequency and Voltage
Protection Settings for Generating Resources) does not include
frequency ride through performance requirements that address the unique
protection and control functions of IBRs. In particular, the
Reliability Standard PRC-024-3 requirement for specific relay
protection frequency settings does not address momentary cessation. As
a result, registered IBRs are not required to continually produce real
power and support frequency inside the ``no trip zone'' during a
frequency excursion.\125\
---------------------------------------------------------------------------
\125\ Reliability Standard PRC-024-3, Attachment 1, nn.8, 9.
There is no explicitly stated expected performance requirements for
IBRs while system operating conditions are within the no-trip zone.
Therefore, IBRs could continue to act adversely in response to
normally cleared faults by continuing to exhibit momentary cessation
and power reduction behaviors.
---------------------------------------------------------------------------
58. In the Blue Cut Fire Event Report, NERC and WECC found that
inverters that ``trip instantaneously based on near instantaneous
frequency measurements are susceptible to erroneous tripping during
transients generated by faults'' on the Bulk-Power System.\126\ In
response, NERC and WECC recommended a review of Reliability Standard
PRC-024-2 to determine whether to modify it for clarity and to ensure a
more accurate representation of Bulk-Power System frequency
measurement.\127\ Shortly after the Blue Cut Fire Event Report, NERC
also issued the Loss of Solar Resources Alert I identifying and
recommending corrective action to prevent similar IBR responses in the
future.\128\
---------------------------------------------------------------------------
\126\ Blue Cut Fire Event Report at v, 15.
\127\ Id.
\128\ Loss of Solar Resources Alert I at 1-2.
---------------------------------------------------------------------------
59. On July 9, 2020, the Commission approved Reliability Standard
PRC-024-3, which addressed some of the reliability gaps in Reliability
Standard PRC-024-2 that NERC found contributed to the outages during
the August 2016 Blue Cut Fire event system disturbance.\129\ For
example, Reliability Standard PRC-024-3 clarifies that the ``applicable
protection does not cause the generating resource to trip or cease
injecting current within the `no trip zone' during a frequency
excursion. . . .'' \130\ In addition, Reliability Standard PRC-024-3
requires that frequency be calculated over a window of time and
clarifies that instantaneous trip settings based on instantaneously-
calculated frequency measurement are not permissible.\131\ However,
Reliability Standard PRC-024-3 does not require registered IBRs (or any
generator) to remain connected to the Bulk-Power System and to continue
to produce real power and support frequency inside the ``no trip
zone.'' This reliability gap led to NERC and Texas RE recommending in
the 2021 Odessa Disturbance Report the development of a new ride
through standard to replace Reliability Standard PRC-024-3 focusing
specifically on generator-ride through performance.\132\
---------------------------------------------------------------------------
\129\ N. Am. Elec. Reliability Corp., Docket No. RD20-7-000
(July 9, 2020) (delegated letter order).
\130\ Cessation of current injection was not included in
Reliability Standard PRC-024-2. See also Reliability Standard PRC-
024-3, Requirement R1 & Attachment 1, n.9.
\131\ Reliability Standard PRC-024-3, Attachment 1, n.9.
\132\ Odessa Disturbance Report at 30.
---------------------------------------------------------------------------
b. Voltage Ride Through
60. The Reliability Standards do not require registered IBRs to
continually produce real power and support voltage inside the ``no trip
zone'' during a voltage excursion. The Reliability Standards also do
not have voltage ride through performance requirements that address the
unique protection and control functions of registered IBRs that can
cause tripping and momentary cessation, even when the IBR voltage
protection settings are compliant with Reliability Standard PRC-024-3.
Keeping generation resources connected to the grid during and after a
Bulk-Power System disturbance is critical to maintaining reliability.
During both Bulk-Power System fault and post-fault periods, the
transmission system experiences voltage depressions. Additionally, the
transmission system may experience high voltages during post-fault
recovery periods. Voltage fluctuations during system disturbances may
lead to IBRs tripping and momentary cessation, which can exacerbate
Bulk-Power System recovery.
61. Since first identifying that IBRs momentarily cease current
injection or trip in response to voltage fluctuations during system
disturbances, NERC has continued to find that the majority of installed
inverters fail to continuously inject active or reactive current during
abnormal voltages (i.e., ride through).\133\ Through event reports,
NERC and WECC have recommended that momentary cessation should not be
used for new IBRs and ``should be eliminated or mitigated to the
greatest extent possible for existing [IBRs] connected to the [Bulk-
Power System].'' and WECC also noted that for existing IBRs with an
equipment limitation that requires momentary cessation, ``active
current injection following voltage recovery should be restored very
quickly (within 0.5 seconds).'' \134\
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\133\ Blue Cut Fire Event Report at 9; Canyon 2 Fire Event
Report at 14, 16-17, 20; Angeles Forest and Palmdale Roost Events
Report at 13, 15, 19; San Fernando Disturbance Report at iv, 2-9.
\134\ Canyon 2 Fire Event Report at 19.
---------------------------------------------------------------------------
62. In addition to event reports, NERC has also recommended in the
Loss of Solar Resources Alert II that registered IBR owners and
operators as well as unregistered IBR owners and operators take action
to address voltage ride through and ensure the timely restoration of
current injection following momentary cessation by all inverter-based
resources connected to the Bulk-Power System.\135\ NERC also
recommended that solar PV IBR owners should ``[w]ork with their
inverter manufacturer(s) to identify the changes that can be made to
eliminate momentary cessation of current injection to the greatest
extent possible, consistent with equipment capability.'' \136\
---------------------------------------------------------------------------
\135\ Loss of Solar Resources Alert II at 1.
\136\ Id. at 2-3.
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[[Page 74555]]
63. For IBRs for which momentary cessation cannot be eliminated
entirely, NERC recommended that generator owners should identify the
changes that can be made to inverter settings to minimize the impact of
momentary cessation on the Bulk-Power System.\137\ NERC also
recommended that solar PV IBR owners should ``consult with their
inverter manufacturer(s) and their PV panel manufacturer(s) to
implement inverter DC reverse current protection settings based on
equipment limitations, such that the resource will not trip
unnecessarily during high voltage transients on the [Bulk-Power
System.]'' \138\ Also in the IBR Performance Guideline, NERC recommends
reducing the recovery delay on the order of one to three electrical
cycles and return to full active power within one second. The only
exception to the return to service recommendation is when the
transmission planner or generation interconnection studies specify a
longer period to return to normal operations. Longer restoration
periods would require other essential reliability services from other
generators to be deployed to arrest frequency decline and provide
voltage support when IBRs trip or do not return to service in a timely
manner.\139\
---------------------------------------------------------------------------
\137\ Id. at 3.
\138\ Id. at 4.
\139\ NERC IBR Performance Guideline at 13, 68.
---------------------------------------------------------------------------
c. Post-Disturbance IBR Ramp Rate Interactions
64. The Reliability Standards do not ensure that all generation
resources that momentarily cease operation following a system
disturbance return to pre-disturbance output levels without impeded
ramp rates. In the Canyon 2 Fire Event Report, NERC and WECC explained
that impeded ramp rates need to be ``remediated to ensure [Bulk-Power
System] transient and frequency stability.'' \140\ Further, NERC and
WECC found that IBR ramp rates are artificially bounded, resulting in
IBRs returning to pre-disturbance outputs slower than desired--ranging
from seconds to several minutes--because plant-level controller ramp
rate limits used for balancing generation and load are being applied to
IBRs following momentary cessation.\141\ For IBRs that cannot eliminate
momentary cessation, NERC and WECC recommended that active current
injection should not be restricted by a plant-level controller or other
limits on ramp rates.\142\ NERC and WECC also recommended that IBR
owners should remediate post-disturbance ramp rate limitations in close
coordination with their balancing authority and inverter manufacturers
while ensuring that ramp rates are enabled appropriately to control
generation-load balance.\143\
---------------------------------------------------------------------------
\140\ Canyon 2 Fire Event Report at 9.
\141\ Id. at 9-11, 19; see also Blue Cut Fire Event Report at 15
(observing that during the Blue Cut Fire Event, some inverters that
went into momentary cessation mode returned to pre-disturbance
levels at a slow ramp rate).
\142\ Canyon 2 Fire Event Report at v.
\143\ Id. See also Loss of Solar Resources Alert II at 3
(recommending that IBR solar PV generators owners ensure that
inverter restoration from momentary cessation should not be impeded
by plant-level control ramp rates); see also Angeles Forest and
Palmdale Roost Events Report at 14-15 (reiterating the findings and
recommendations from the Loss of Solar Resources Alert II); see also
San Fernando Disturbance Report at iv (explaining that some IBRs
returned to pre-disturbance power output levels quickly (i.e.,
around one second) while the majority of IBRs had longer ramp rates
and required substantially more time to return to pre-disturbance
power output levels).
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d. Phase Lock Loop Synchronization
65. The Reliability Standards do not require that all generation
resources maintain voltage phase angle synchronization with the Bulk-
Power System grid voltage during a system disturbance. IBRs will
momentarily cease current injection into the grid due to protection and
control settings during Bulk-Power System disturbance events if IBRs
lose synchronization with grid voltage (i.e., phase lock loop loss of
synchronism). The Odessa Report explained that phase lock loop loss of
synchronism was the largest contributor to the reduction of solar PV
output during the reported Bulk-Power System disturbance event.\144\
---------------------------------------------------------------------------
\144\ Odessa Report at 8.
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66. For IBRs, an inverter phase lock loop ``continually monitors
the phase angle difference between the inverter [AC] voltage command
and the grid-side [AC] voltage.'' \145\ The phase lock loop also
``adjusts the internal phase angle of current injection to remain
synchronized with the [AC] grid.'' \146\ Synchronous generation
resources do this automatically through electromagnetic coupling
whereby mechanical energy from the turbine is converted to electrical
energy in the magnetic field of the generator, which is synchronized
with the system.\147\ For certain disturbances, a ``rapid change in
inverter terminal phase angle can pose challenges for the [phase lock
loop] to track the terminal voltage angle.'' \148\ In some instances, a
phase lock loop ``loss of synchronism'' may occur.\149\ Proper tracking
of voltage phase angle is required for a successful and effective
synchronization of the inverter with the grid.
---------------------------------------------------------------------------
\145\ IBR Interconnection Requirements Guideline at 9 (footnotes
omitted).
\146\ Id.
\147\ Edvard, Mysterious Synchronous Operation of Generator
Solved, <a href="http://Electrical-Engineering-Portal.com">Electrical-Engineering-Portal.com</a>, (Jun. 2013), <a href="https://electrical-engineering-portal.com/mysterious-synchronous-operation-of-generator">https://electrical-engineering-portal.com/mysterious-synchronous-operation-of-generator</a>.
\148\ IBR Interconnection Requirements Guideline at 9.
\149\ Id. at 10 (this is a protective function that operates
when the angle difference between the phase generated by the phase
lock loop and the grid phase exceeds a threshold for a predetermined
period, typically on the order of a couple of milliseconds).
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67. The Canyon 2 Fire Event Report found that some IBRs experienced
a momentary loss of synchronism with the AC grid waveform during the
disturbance, which resulted in protective action opening the primary
circuit breaker followed by a five-minute restart action.\150\ NERC and
WECC recommended that IBRs should ``ride through momentary loss of
synchronism'' during Bulk-Power System disturbances and that they
should continue to inject current into the Bulk-Power System during the
disturbance.\151\
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\150\ Canyon 2 Fire Event Report at 15-16, 20.
\151\ Id.
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IV. Proposed Directives
68. We preliminarily find that the Reliability Standards do not
adequately address the impacts of IBRs on the reliable operation of the
Bulk-Power System. Informed by the IBR events, reports, alerts, and
guidelines discussed above, we preliminarily find that changes to the
Reliability Standards are necessary to appropriately address IBRs and
their impacts on Bulk-Power System operations.
69. Pursuant to section 215(d)(5) of the FPA and Sec. 39.5(f) of
the Commission's regulations, we therefore propose to direct NERC to
develop and submit new or modified Reliability Standards that address
the impacts of IBRs on the reliable operation of the Bulk-Power System
as described in more detail below. Given the current and projected
increased proportion of IBRs within the Bulk-Power System generation
fleet,\152\ we propose to direct NERC to develop new or modified
Reliability Standards that address: (1) IBR data sharing; (2) IBR model
validation; (3) IBR planning and operational studies; and (4)
registered IBR performance requirements.
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\152\ See, e.g., 2020 LTRA Report at 9.
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70. We appreciate that NERC has initiated several standard drafting
projects relating to IBRs,\153\ but we
[[Page 74556]]
believe that a comprehensive review and development of new or modified
Reliability Standards to address IBRs is necessary to assure that IBRs
are properly considered in Bulk-Power System planning and that their
operational characteristics--such as momentary cessation--are
addressed.\154\ Developing new or modified Reliability Standards to
comprehensively address the reliability impacts of IBRs will help
ensure the reliable operation of the Bulk-Power System as the
transition to a future resource mix that includes a high level of IBR
penetration continues.
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\153\ NERC 2022-2024 Reliability Standards Development Plan.
\154\ See 2021 Solar PV Disturbances Report, vi, 30 (stating
that the report ``strongly reiterates the recommendations in the
Odessa Disturbance Report regarding the need to modernize and update
the . . . Reliability Standards.'').
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71. Given the variety of concerns related to IBRs, there may be
efficiencies in developing a new IBR-specific Reliability Standard or
Standards that address IBR issues in a comprehensive manner. Further,
considering the directives in the related IBR registration order issued
concurrently with this NOPR,\155\ a new Reliability Standard or
Standards may also be more easily developed for the newly registered
IBR-only generator owners and operators of currently unregistered IBRs
that fall outside the current bulk electric system definition but that,
in the aggregate, materially impact the reliable operation of the Bulk-
Power System.\156\ We do not propose to direct any specific method for
addressing the reliability concerns discussed herein; rather, NERC has
the discretion, subject to Commission review and approval, to address
the reliability concerns by developing one or more new Reliability
Standards or modifying currently effective Reliability Standards.
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\155\ See Registration of Inverter-based Resources, 181 FERC ]
61,124 at P 32 (directing that NERC identify and register
unregistered IBRs that, in the aggregate, have a material impact on
the reliable operation of the Bulk-Power System, but that are not
currently required to be registered with NERC under the [bulk
electric system] definition.'').
\156\ Id. P 33 (``NERC may determine that the full set of
Reliability Standard Requirements otherwise applicable to generator
owners and operators need not apply to currently unregistered IBR
generator owners and operators when they are registered.'' (citation
omitted)).
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72. We propose to direct NERC to submit a compliance filing within
90 days of the effective date of the final rule in this proceeding.
That compliance filing shall include a detailed, comprehensive
standards development and implementation plan explaining how NERC will
prioritize the development and implementation of new or modified
Reliability Standards. In its compliance filing, NERC should explain
how it is prioritizing its IBR Reliability Standard projects to meet
the directives in the final rule, taking into account the risk posed to
the reliability of the Bulk-Power System, standard development projects
already underway, resource constraints, and other factors as necessary.
73. We propose to direct NERC to use a staggered approach that
would result in NERC submitting new or modified Reliability Standards
in three stages: (1) new or modified Reliability Standards including
directives related to registered IBR failures to ride through frequency
and voltage variations during normally cleared Bulk-Power System faults
shall be filed with the Commission within 12 months of Commission
approval of the plan; (2) new or modified Reliability Standards
addressing the interconnected directives related to registered IBR,
unregistered IBR, and IBR-DER data sharing, registered IBR disturbance
monitoring data sharing, registered IBR, unregistered IBR, and IBR-DER
data and model validation, and registered IBR, unregistered IBR, and
IBR-DER planning and operational studies shall be filed with the
Commission within 24 months of Commission approval of the plan; and (3)
new or modified Reliability Standards including the remaining
directives for post-disturbance ramp rates and phase-locked loop
synchronization shall be filed with the Commission within 36 months of
Commission approval of the plan. We believe this staggered approach to
standard development may be necessary based on the scope of work
anticipated and that specific target dates will provide a valuable tool
and incentive to NERC to timely address the directives in the final
rule.
74. NERC should also reflect in its compliance filing that the
proposed directives for individual and aggregate registered IBRs and
unregistered IBRs, as well as IBR-DERs in the aggregate, related to
data sharing, validation, and use in studies are interdependent. For
example, data models and validation build and rely upon the data
sharing directives. Similarly, the planning and operational study
directives require the use of validated models and data sharing. We
believe that this proposal strikes a reasonable balance between the
need to timely implement identified improvements to the Reliability
Standards that will further Bulk-Power System reliability and the need
for NERC to develop modifications with industry input using its open,
stakeholder process.
75. We seek comments from NERC and other interested entities on
this staggered approach, including the 90-day timeframe to submit a
compliance filing with a development and implementation plan, and on
all other proposals in this NOPR.
A. IBR and IBR-DER Data Sharing
76. We preliminarily find that the current Reliability Standards
are inadequate to ensure that sufficient data of registered IBRs and
unregistered IBRs, and IBR-DER data in the aggregate is provided to the
registered entities responsible for planning, operating, and analyzing
disturbances on the Bulk-Power System. The currently effective
Reliability Standards, such as TOP-003-4 (Operational Reliability Data)
and IRO-010-3 (Reliability Coordinator Data Specification and
Collection), require the data recipient (e.g., transmission operator,
reliability coordinator) to specify a list of data to be provided, and
obligates other identified registered entities (e.g., generator owner,
generator operator, transmission owner, distribution provider) to
provide the specified data. Although Reliability Standards TOP-003-4
and IRO-010-3, along with other data-related Reliability Standards
(including MOD-032-1 and PRC-002-2) are effective and enforceable, we
preliminarily find that these Reliability Standards do not require
generator owners, generators operators, transmission owners, and
distribution providers to provide data that represents the behavior of
both individual and aggregate registered IBRs and unregistered IBRs, as
well as IBR-DERs in the aggregate, at a sufficient level of fidelity
for planners and operators to accurately plan, operate, and analyze
disturbances on the Bulk-Power System.
77. To address this gap in the Reliability Standards, we propose to
direct NERC to develop new or modified Reliability Standards that
identify: (1) the registered entities that must provide certain data of
registered IBRs and unregistered IBRs, as well as IBR-DER data in the
aggregate; (2) the recipients of that registered IBR, unregistered IBR,
and IBR-DER data; (3) the minimum categories or types of registered
IBR, unregistered IBR, and IBR-DER related data that must be provided;
and (4) the timing and periodicity for the provision of registered IBR,
unregistered IBR, and IBR-DER data needed for modeling, operations, and
disturbance analysis to the appropriate registered entities and the
review of that data by those entities.
78. Further, we propose to direct NERC to ensure that the new or
modified Reliability Standards require registered generator owners and
generator operators of registered IBRs to provide registered IBR-
specific
[[Page 74557]]
modeling data and parameters (e.g., steady-state, dynamic and short
circuit modeling information, and control settings for momentary
cessation and ramp rates) that are complete and accurate to their
planning coordinators, transmission planners, reliability coordinators,
transmission operators, and balancing authorities that are responsible
for planning and operating the Bulk-Power System. This approach would
provide the registered entities responsible for planning and operating
the Bulk-Power System with accurate data on registered IBRs. We propose
to direct NERC to include technical criteria for having disturbance
monitoring equipment at buses and elements of registered IBRs to ensure
disturbance monitoring data is available to the planners and operators
for analyzing disturbances on the Bulk-Power System and to validate
registered IBR models.
79. We also preliminarily find that planning coordinators and other
entities also need modeling data and parameters from both unregistered
IBRs as well as IBR-DERs in the aggregate to assure greater accuracy in
modeling. We propose to direct that the new or modified Reliability
Standards addressing IBR data sharing require transmission owners to
provide modeling data and parameters (e.g., steady-state, dynamic and
short circuit modeling information, and control settings for momentary
cessation and ramp rates) for unregistered IBRs in their transmission
owner areas where the unregistered IBRs that individually or in the
aggregate materially affect the reliable operation of the Bulk-Power
System. Similarly, where entities that own or operate IBR-DERs that, in
the aggregate, materially affect the reliability of the Bulk-Power
System and are not subject to compliance with Reliability Standards, we
propose to direct that the new or modified Reliability Standards
addressing IBR data sharing require that the distribution provider
provide modeling data and parameters for IBR-DERs in the aggregate
connected in its distribution provider area.\157\
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\157\ NERC, Reliability Guideline: Parameterization of the DER A
Model, 8-16 (Sept. 2019), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf</a>.
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80. This approach would be similar to other Reliability Standards
that require transmission owners and distribution providers to provide
certain planning and operational data received from unregistered
entities.\158\ Moreover, given the small size and location of many of
the IBR-DERs on the distribution system, we recognize that it may not
be practical for distribution providers to provide modeling data and
parameters to model individual IBR-DERs directly. Instead, the new or
modified Reliability Standards should permit distribution providers to
provide IBR-DER modeling data and parameters in the aggregate or
equivalent for IBR-DERs interconnected to their distribution systems
(e.g., IBR-DERs in the aggregate and modeled by resource type such as
wind or solar PV, or IBR-DERs in the aggregate and modeled by
interconnection requirements performance to represent different steady-
state and dynamic behavior).\159\
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\158\ This approach is consistent with certain currently
effective Reliability Standards. See, e.g., Reliability Standard
IRO-010-2 (Reliability Coordinator Data Specification and
Collection) Requirement R1 (providing that ``[t]he Reliability
Coordinator shall maintain a documented specification for the data .
. . including non-[bulk electric system] data''(emphasis added)),
Requirement R2 (providing that ``[t]he Reliability Coordinator shall
distribute its data specification to entities''), Requirement R3
(providing that ``[e]ach . . . Transmission Owner, and Distribution
Provider receiving a data specification in Requirement R2 shall
satisfy the obligations of the documented specifications'');
Reliability Standard PRC-006-3 (Automatic Underfrequency Load
Shedding) Requirement R8 (requiring that a UFLS entity, i.e.,
relevant transmission owner and distribution provider, ``provide
data to its Planning Coordinator(s)'').
\159\ NERC DER Report at 7 (explaining ``a certain degree of
simplification may be needed either by model aggregation (i.e.,
clustering of models with similar performance), by derivation of
equivalent models (i.e., reduced-order representation), or by a
combination of the two.''). See also NERC, Reliability Guideline:
Parameterization of the DER A Model, (Sept. 2019), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf</a>.
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81. We believe that these proposed directives will ensure that
entities such as planning coordinators and reliability coordinators
receive accurate and complete data about IBRs, both registered IBRs and
unregistered IBRs, as well as IBR-DERs in the aggregate to properly
plan, operate, and analyze performance on the Bulk-Power System to
ensure reliable operations.
B. IBR and IBR-DER Data and Model Validation
82. We preliminarily find that the existing Reliability Standards
are inadequate to ensure that planners and operators: (1) have the
steady state, dynamic, and short circuit models of the elements that
make up generation, transmission, and distribution facilities that
accurately reflect the generator behavior in steady state and dynamic
conditions; (2) have dynamic models (i.e., models of equipment that
reflect the equipment's behavior during various grid conditions and
disturbances) that accurately represent the dynamic performance of all
generation resources, including momentary cessation when applicable;
(3) validate and update resource models by comparing the provided data
and resulting models against actual operational behavior to achieve and
maintain necessary accuracy of their resource models; and (4) have
interconnection-wide planning and operational models that represent all
generation resources, including: registered IBRs, unregistered IBRs,
and IBR-DERs; synchronous generation; and load resource models. System
planners and operators need accurate planning, operational, and
interconnection-wide models to ensure reliable operation of the system.
83. We therefore propose to direct NERC to submit to the Commission
for approval one or more new or modified Reliability Standards that
would ensure that all necessary models are validated. Specifically,
NERC should ensure that the Reliability Standards require: (1)
generator owners to provide validated registered IBR models to the
planning coordinators for interconnection-wide planning and operational
models; (2) require transmission owners to provide validated
unregistered IBR models to the planning coordinators for
interconnection-wide planning and operational models; and (3) require
distribution providers to provide validated models of IBR-DERs in the
aggregate (e.g., IBR-DERs in the aggregate and modeled by resource type
such as wind or solar PV, or IBR-DERs in the aggregate and modeled by
interconnection requirements performance to represent different steady-
state and dynamic behavior) to the planning coordinators for
interconnection-wide planning and operational models. Further, NERC
should ensure that the new or modified Reliability Standards require
models of individual registered IBRs and unregistered IBRs, as well as
IBR-DERs in the aggregate to represent the dynamic behavior of these
IBRs at a sufficient level of fidelity for planners and operators to
perform valid facility interconnection, planning, and operational
studies on a basis comparable to synchronous generation resources.
84. The Reliability Standards do not require a generator owner to
provide verified models and data for IBR-specific controls (e.g., power
plant central controller functions and protection system settings) and
do not require verified dynamic models from the transmission owner for
unregistered IBRs or require verified IBR-DERs dynamic models in the
aggregate from distribution providers. We therefore
[[Page 74558]]
propose to direct that the proposed new or modified Reliability
Standards account for the technological differences between Bulk-Power
System IBRs and synchronous generation resources. We also propose to
direct NERC to require generator owners of registered IBRs and
transmission owners that have unregistered IBRs on their system to
ensure that the dynamic models provided to the planning coordinators,
transmission planners, reliability coordinators, transmission
operators, and balancing authorities accurately represent the dynamic
performance of registered IBR and unregistered IBR facilities,
including momentary cessation and/or tripping, including all ride
through behavior. Further, we propose to direct NERC to require
distribution providers that have IBR-DERs on their system to ensure
that the aggregated dynamic models provided to the planning
coordinators, transmission planners, reliability coordinators,
transmission operators, and balancing authorities accurately represent
the dynamic performance of IBR-DER facilities in the aggregate,
including momentary cessation and/or tripping, including all ride -
through behavior (e.g., IBR-DERs in aggregate modeled by
interconnection requirements performance to represent different steady-
state and dynamic behavior).
85. We also preliminarily find that there is a coordination gap
among registered entities that build and verify interconnection-wide
cases. Reliability Standards MOD-032-1 and MOD-033-2 functional
entities and designees are not required to work collaboratively to
create interconnection-wide cases that accurately reflect real-world
interconnection-wide IBR performance and behavior. Therefore, we
propose to direct NERC to ensure that the new or modified Reliability
Standards require planning coordinators, transmission planners,
reliability coordinators, transmission operators, and balancing
authorities to validate, coordinate, and keep up-to-date in a timely
manner \160\ the verified data and models of registered IBRs,
unregistered IBRs, and IBR-DERs in the aggregate by comparing their
data and resulting models against actual operational behavior to
achieve and maintain necessary modeling accuracy of individual and
aggregate registered IBR and unregistered IBR performance and
behaviors, as well as performance and behaviors of IBR-DERs in the
aggregate.
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\160\ Panhandle Report at 19 (recommending that the performance
validation feedback loop is addressed in a timely manner).
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86. Finally, without approved generator models that accurately
reflect the generator behavior in steady state and dynamic conditions,
we preliminarily find that planners and operators are unable to
adequately predict IBR behavior and their subsequent impact on the
Bulk-Power System.\161\ The Reliability Standards do not require the
use of NERC's approved component models, instead models are referred to
generally in Reliability Standard MOD-032-1, Attachment 1.\162\ We
therefore propose to require that the new or modified Reliability
Standards require the use of approved industry IBR models that
accurately reflect the behavior of IBRs during both steady state and
dynamic conditions. One way to do this would be to reference NERC's
approved model list in the Reliability Standards and require that only
those models be used when developing planning, operational, and
interconnection-wide models. The proposed directives are consistent
with the recommendations in NERC reports.\163\
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\161\ NERC Standardized Powerflow Parameters and Dynamics Models
(explaining that there is a growing need for accurate
interconnection[hyphen]wide powerflow and dynamics simulations that
analyze phenomena such as: frequency response, inter-area
oscillations, and interactions between the growing numbers of wide-
area control and protections systems).
\162\ Reliability Standard MOD-032-1, Attachment 1 (explaining
that if a user-written model(s) is submitted in place of a generic
or library model, it must include the characteristics of the model,
including block diagrams, values and names for all model parameters,
and a list of all state variables).
\163\ See, e.g., Modeling and Studies Report at 37 (recommending
revising Reliability Standards to ensure that large disturbance
behavior of IBRs is verified); WI Base Case IBR Review at v
(recommending that IBR owners ensure that all data fields are
reported correctly and that transmission planners and planning
coordinators ``should verify that the data fields are submitted
correctly'').
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C. IBR and IBR-DER Planning and Operational Studies
87. We preliminarily find that the existing Reliability Standards
are inadequate to ensure planning and operational studies: (1) assess
performance and behavior of both individual and aggregate registered
IBRs and unregistered IBRs as well as IBR-DERs in the aggregate; (2)
have and use validated modeling and operational data for individual
registered IBRs and unregistered IBRs, as well as IBR-DERs in the
aggregate; and (3) account for the impacts of both individual and
aggregate registered IBRs and unregistered IBRs, as well as IBR-DERs in
the aggregate, within and across planning and operational boundaries
for normal operations and contingency event conditions. Planning and
operational studies must use validated IBR modeling and operational
data to ensure studies account for the actual behavior of both
individual and aggregate registered IBRs and unregistered IBRs, as well
as IBR-DERs in the aggregate.
1. Planning Studies
88. We preliminarily find that the Reliability Standards do not
ensure accurate planning studies of Bulk-Power System performance over
a broad spectrum of system conditions and following a wide range of
probable contingencies that includes all resources. Inaccurate planning
assessments may lead to false expectations that system performance
requirements are met and may inadvertently mask potential reliability
risks in planning and operations. We therefore propose to direct NERC
to submit to the Commission for approval one or more new or modified
Reliability Standards that would require planning coordinators and
transmission planners to include in their planning assessments the
study and evaluation of performance and behavior of individual and
aggregate registered IBRs and unregistered IBRs, as well as IBR-DERs in
the aggregate, under normal and contingency system conditions in their
planning area. We further propose that the planning assessments include
the study and evaluation of the ride through performance (e.g.,
tripping and momentary cessation conditions) of such IBRs in their
planning area for stability studies on a comparable basis to
synchronous generation resources. The proposed Reliability Standard(s)
would also require planning coordinators and transmission planners to
consider the individual and aggregate behavior of registered IBRs and
unregistered IBRs, as well as IBR-DERs in the aggregate, using planning
models of their area, and, using interconnection-wide area planning
models, IBR behavior in adjacent and other planning areas that
adversely impacts a planning coordinator's or transmission planner's
area during a disturbance event. We believe that this is needed because
registered IBRs, unregistered IBRs, and IBR-DERs tend to act in the
aggregate over a wide area during such an event.\164\
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\164\ 2021 Solar PV Disturbances Report at v (stating that ``The
ongoing widespread reduction of solar PV resources continues to be a
notable reliability risk to the [Bulk-Power System], particularly
when combined with the additional loss of other generating resources
on the [Bulk-Power System] and in aggregate on the distribution
system.''); see also Odessa Disturbance Report at v (stating that
``[w]hile the ERO has analyzed multiple similar events in
California, this is the first disturbance involving a widespread
reduction of solar photovoltaic (PV) resource power output observed
in the Texas Interconnection.''); Blue Cut Fire Event Report at 2
(explaining that the system disturbance event was ``impactful
because of the widespread loss . . . of PV generation.'').
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[[Page 74559]]
2. Operational Studies
89. We preliminarily find that the Reliability Standards do not
require that the various operational studies (including operational
planning analyses, real-time monitoring, real-time assessments and
other analysis functions) include all resources to adequately assess
the performance of the Bulk-Power System for normal and contingency
conditions. We therefore propose to direct NERC to submit to the
Commission for approval one or more new or modified Reliability
Standards that would require reliability coordinators and transmission
operators to include the performance and behavior of both individual
and aggregate registered IBRs and unregistered IBRs, as well as IBR-
DERs in the aggregate (e.g., IBRs tripping or entering momentary
cessation individually or in the aggregate) in their operational
planning analysis,\165\ real-time monitoring, and real-time assessments
\166\ including non-bulk electric system data and external power system
network data identified in their data specifications.\167\ We further
propose to direct NERC to submit to the Commission for approval one or
more new or modified Reliability Standards that would require balancing
authorities to include the performance and behavior of both individual
and aggregate registered IBRs and unregistered IBRs, as well as IBR-
DERs in the aggregate (e.g., resources tripping or entering momentary
cessation individually or in the aggregate) in their operational
analysis functions and real-time monitoring.\168\ This proposal is
consistent with the recommendations in the NERC DER Report, IBR
Performance Guideline, IBR-DER Data Collection Guideline, and Loss of
Solar Resources Alert II. These reports indicate that a significant
amount of IBRs that have been involved in system disturbances were not
adequately modeled in interconnection-wide cases and tools used to
study the performance and behavior of both individual and aggregate
registered IBRs and unregistered IBRs, as well as IBR-DERs in the
aggregate.\169\ Thus, neighboring operators may be unaware that faults
in one operator's area can trigger controls actions and trip IBRs in
another operator's area.
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\165\ NERC defines operational planning analysis as ``An
evaluation of projected system conditions to assess anticipated
(pre-Contingency) and potential (post-Contingency) conditions for
next-day operations. The evaluation shall reflect applicable inputs
including, but not limited to, load forecasts; generation output
levels; Interchange; known Protection System and Special Protection
System status or degradation; Transmission outages; generator
outages; Facility Ratings; and identified phase angle and equipment
limitations. (Operational Planning Analysis may be provided through
internal systems or through third-party services).'' NERC Glossary.
\166\ NERC defines real-time assessment as an ``evaluation of
system conditions using Real-time data to assess existing (pre-
Contingency) and potential (post-Contingency) operating conditions.
The assessment shall reflect applicable inputs including, but not
limited to: load, generation output levels, known Protection System
and Special Protection System status or degradation, Transmission
outages, generator outages, Interchange, Facility Ratings, and
identified phase angle and equipment limitations. (Real-time
Assessment may be provided through internal systems or through
third-party services).'' Id.
\167\ See, e.g., Reliability Standard IRO-010-2, Requirement R1,
part 1.1 and Reliability Standard TOP-003-3 (Operational Reliability
Data), Requirement R1, part 1.1.
\168\ See, e.g., Reliability Standard TOP-003-3, Requirement R2,
part 2.1.
\169\ Modeling and Studies Report iv-v.
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D. IBR Performance Requirements
90. We preliminarily find that the Reliability Standards should
require registered IBRs to ride through system disturbances to support
essential reliability services. Without the availability of essential
reliability services, the system would experience instability, voltage
collapse, or uncontrolled separation.\170\ Therefore, we propose to
direct NERC to develop new or modified Reliability Standards that would
require generator owners and generator operators to ensure that their
registered IBR facilities ride through system frequency and voltage
disturbances where technologically feasible. Ride through performance
during system disturbances is necessary for registered IBRs to support
essential reliability services.\171\ We propose to direct NERC to
ensure that the proposed new or modified Reliability Standards clearly
address and document the technical differences and technical
capabilities between registered IBRs and synchronous generation
resources in order for registered IBRs to provide support for these
essential reliability services.\172\
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\170\ Essential Reliability Services Concept Paper at iii.
\171\ NERC defines essential reliability services to include
``necessary operating characteristics'' provided by ``[c]onventional
generation with large rotating mass,'' which are ``needed to
reliably operate the North American electric grid.'' NERC explains
that essential reliability services ``are an integral part of
reliable operations to assure the protection of equipment, and are
the elemental `reliability building blocks' provided by
generation.'' Id.
\172\ There are similar reliability impacts posed by tripping or
momentary cessation of unregistered IBRs and IBR-DERs during Bulk-
Power System disturbances; however, we are not proposing to direct
NERC to develop new or modified Reliability Standards that would
address unregistered IBR or IBR-DER performance requirements. We
expect that any currently unregistered IBRs that become registered
IBRs in the future following an approved NERC workplan in Docket No.
RD22-4-000 would be required to comply with any applicable new or
modified IBR performance Reliability Standards proposed in this NOPR
once those Reliability Standards become enforceable.
---------------------------------------------------------------------------
91. We also propose to direct NERC to develop new or modified
Reliability Standards to address other registered IBR performance and
operational characteristics that can affect the reliable operation of
the Bulk-Power System, namely, ramp rate interactions and phase-locked
loop synchronization.
92. We believe the proposed directives would improve the reliable
operation of the Bulk-Power System by helping to avoid instability,
voltage collapse, uncontrolled separation, or islanding.
1. Frequency Ride Through
93. We preliminarily find that the currently effective Reliability
Standards do not require registered IBR reliable frequency ride through
performance during system disturbances. The frequency of an
interconnection depends on the instantaneous balance between load and
generation resources to which all resources must contribute during both
normal and contingency conditions. However, the Reliability Standard
PRC-024-3 requirement for specific relay protection frequency settings
does not ensure adequate registered IBR performance because IBRs could
have protection and control functions that can cause the resource to
trip or momentarily cease operation even when the IBR frequency
protection settings are compliant with the standard. We therefore
propose to direct NERC to submit to the Commission for approval one or
more new or modified Reliability Standards that would require
registered IBR generator owners and registered IBR generator operators
to use appropriate settings (i.e., inverter, plant controller, and
protection) that will assure frequency ride through during system
disturbances and that would permit registered IBR tripping only to
protect the registered IBR equipment. Under this proposal, any new or
modified Reliability Standards should require registered IBRs to
continue to produce power and perform frequency support during system
disturbances. We believe this proposal is consistent with
[[Page 74560]]
recommendations from multiple event reports, including the Blue Cut
Fire Event Report,\173\ the Odessa Disturbance Report,\174\ and most
recently the 2021 Solar PV Disturbances Report.\175\
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\173\ Blue Cut Fire Report at 11-13.
\174\ Odessa Disturbance Report at vii, 12-13.
\175\ 2021 Solar PV Disturbances Report at vii, 15, 31.
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2. Voltage Ride Through
94. We preliminarily find that the currently effective Reliability
Standards do not adequately address registered IBR protection and
controls settings to allow for voltage ride through during system
disturbances (as discussed above in Section III.B.4.b. Voltage Ride
Through). We propose to direct NERC to submit to the Commission for
approval one or more new or modified Reliability Standards that would
require registered IBR generator owners and registered IBR generator
operators to use appropriate and coordinated registered IBR protection
and controls settings that will allow for voltage ride through during
system disturbances and would permit registered IBR tripping only when
necessary to protect the registered IBR equipment. Under this proposal,
any new or modified Reliability Standard should require generator
owners of registered IBR facilities to ensure that they prohibit
momentary cessation in the no-trip zone during disturbances.\176\
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\176\ We note that Reliability Standard PRC-024-3, Attachments 1
and 2 clarify that the area outside the No Trip Zone is not a Must
Trip Zone.
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95. We are aware that certain registered IBRs currently in
operation may not be able to meet the requirements proposed above.
Therefore, we propose to direct NERC to require transmission planners
and operators to implement mitigation activities that may be needed to
address any reliability impact to the Bulk-Power System posed by these
existing facilities. We believe that planners and operators should be
able to accommodate this limited number of affected existing registered
IBRs, and we expect that the technology of newer IBRs will not require
such accommodation.
3. Post-Disturbance IBR Ramp Rate Interactions
96. We preliminarily find that the current Reliability Standards do
not sufficiently address registered IBR post-disturbance ramp rates
following momentary cessation such that Bulk-Power System transient and
frequency stability is supported during the system disturbances.\177\
We propose to direct NERC to submit to the Commission for approval one
or more new or modified Reliability Standards that would require
registered IBR post-disturbance ramp rate not to be restricted or to
artificially interfere with the resource returning to pre-disturbance
output level in a quick and stable manner after a Bulk-Power System
fault event. Further, we propose generator owners communicate to the
relevant planning coordinators, transmission planners, reliability
coordinators, transmission operators, and balancing authorities the
actual post-disturbance ramp rates and the ramp rates to meet expected
dispatch levels (i.e., generation-load balance). The proposed
Reliability Standards should account for the technical differences
between registered IBRs and synchronous generation resources, such as
registered IBRs' faster control capability to ramp power output down or
up when capacity is available. We believe this proposal is consistent
with the recommendations in various NERC reports discussed above.\178\
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\177\ See Canyon 2 Fire Event Report at 9.
\178\ See, e.g., id. (explaining that impeded ramp rates need to
be ``remediated to ensure [Bulk-Power System] transient and
frequency stability''); Blue Cut Fire Event Report at 15 (observing
that during the Blue Cut Fire Event, some inverters that went into
momentary cessation mode returned to pre-disturbance levels at a
slow ramp rate).
---------------------------------------------------------------------------
4. Phase Lock Loop Synchronization
97. We preliminarily find that the current Reliability Standards do
not require that all generation resources maintain voltage phase angle
synchronization with the Bulk-Power System grid voltage during a system
disturbance (as discussed in above Section III.B.4.d. Phase Lock Loop
Synchronization). In other words, the current Reliability Standards do
not adequately address registered IBR's momentary loss of synchronism
caused by phase jumps during Bulk-Power System disturbance events. This
results in protective action to open the inverter primary circuit
breaker (i.e., phase lock loop loss of synchronism). We propose to
direct NERC to submit to the Commission for approval one or more new or
modified Reliability Standards that would require registered IBRs to
ride through any conditions not addressed by the proposed Reliability
Standards that address frequency or voltage ride through phase lock
loop loss of synchronism. We note that NERC reported that phase lock
loop loss of synchronism was a large contributor to the reduction of
solar PV output during IBR related Bulk-Power System disturbance events
that resulted in the unexpected loss of resources placing additional
reliability risk on the Bulk-Power System.\179\ We believe this
proposal is consistent with the IBR Interconnection Requirements
Guideline and Canyon 2 Fire Event Report recommendations. The proposed
Reliability Standards should require registered IBRs to ride through
momentary loss of synchronism during Bulk-Power System disturbances and
require registered IBRs to continue to inject current into the Bulk-
Power System at pre-disturbance levels during a disturbance.
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\179\ See Section III.B.4.d.
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V. Information Collection Statement
98. This NOPR proposes to direct the ERO to develop and submit to
the Commission for approval one or more new or modified Reliability
Standards and submit a compliance filing that includes a standards
development plan for the new or modified reliability standards that
address IBRs. The Paperwork Reduction Act (PRA) requires each federal
agency to seek and obtain OMB approval before undertaking a collection
of information directed to ten or more persons or contained in a rule
of general applicability. Reliability Standards Development as
described in FERC-725 covers standards development initiated by NERC,
the Regional Entities, and industry, as well as standards the
Commission may direct NERC to develop or modify.
99. The proposal to direct NERC to develop new, or to modify
existing, Reliability Standards (and the corresponding burden) are
covered by, and already included in, the existing OMB-approved
information collection FERC-725 (Certification of Electric Reliability
Organization; Procedures for Electric Reliability Standards; OMB
Control No. 1902-0225), under Reliability Standards Development.\180\
The reporting requirements in FERC-725 include the ERO's overall
responsibility for developing Reliability Standards.
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\180\ Reliability Standards Development as described in FERC-725
covers standards development initiated by NERC, the Regional
Entities, and industry, as well as standards the Commission may
direct NERC to develop or modify.
---------------------------------------------------------------------------
<bullet> Necessity of the Information: The proposed directive to
the ERO to develop and submit to the Commission for approval one or
more new or modified Reliability Standards, if adopted, would implement
the Congressional mandate of the Energy Policy Act of 2005 to develop
mandatory and enforceable Reliability Standards to better ensure the
reliability of the nation's Bulk-Power System.
[[Page 74561]]
Specifically, the proposal would ensure that the ERO develops and
submits for approval new or modified Reliability Standards that would
require certain facilities to operate in support of the reliable
operation of the Bulk-Power System.
<bullet> Internal review: The Commission has reviewed the proposed
directive that the ERO revise its current Reliability Standards and
determined that the proposal is necessary to meet the statutory
provisions of the FPA requiring the Commission to ensure the
reliability of the Bulk-Power System.
100. Interested persons may obtain information on the reporting
requirements by contacting: Federal Energy Regulatory Commission, 888
First Street NE, Washington, DC 20426 [Attention: Ellen Brown, Office
of the Executive Director, email: <a href="/cdn-cgi/l/email-protection#c783a6b3a684aba2a6b5a6a9a4a287a1a2b5a4e9a0a8b1"><span class="__cf_email__" data-cfemail="682c091c092b040d091a09060b0d280e0d1a0b460f071e">[email protected]</span></a>, Phone: (202)
502-8663, fax: (202) 273-0873]. Comments on the requirements of this
rule may also be sent to the Office of Information and Regulatory
Affairs, Office of Management and Budget, Washington, DC 20503
[Attention: Desk Officer for the Federal Energy Regulatory Commission].
For security reasons, comments should be sent by email to OMB at
<a href="/cdn-cgi/l/email-protection#5e31372c3f012d2b3c33372d2d3731301e31333c703b312e70393128"><span class="__cf_email__" data-cfemail="c3acaab1a29cb0b6a1aeaab0b0aaacad83acaea1eda6acb3eda4acb5">[email protected]</span></a>. Please reference OMB Control No. 1902-
0225, FERC-725 and the docket number of this proposed rulemaking in
your submission.
VI. Environmental Assessment
101. The Commission is required to prepare an Environmental
Assessment or an Environmental Impact Statement for any action that may
have a significant adverse effect on the human environment.\181\ The
Commission has categorically excluded certain actions from this
requirement as not having a significant effect on the human
environment. Included in the exclusion are rules that are clarifying,
corrective, or procedural or that do not substantially change the
effect of the regulations being amended.\182\ The actions proposed here
fall within this categorical exclusion in the Commission's regulations.
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\181\ Reguls. Implementing the Nat'l Env't Pol'y Act of 1969,
Order No. 486, 52 FR 47897 (Dec. 17, 1987), FERC Stats. & Regs., ]
30,783 (1987) (cross-referenced at 41 FERC ] 61,284).
\182\ 18 CFR 380.4(a)(2)(ii).
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VII. Regulatory Flexibility Act Certification
102. The Regulatory Flexibility Act of 1980 (RFA) \183\ generally
requires a description and analysis of proposed rules that will have
significant economic impact on a substantial number of small entities.
By only proposing to direct NERC, the Commission-certified ERO, to
develop modifications to Reliability Standards, this NOPR will not have
a significant or substantial impact on entities other than NERC. The
ERO develops and files with the Commission for approval Reliability
Standards affecting the Bulk-Power System, which represents: (a) a
total electricity demand of 830 GW (830,000 MW) and (b) more than $1
trillion worth of assets. Therefore, the Commission certifies that this
NOPR will not have a significant economic impact on a substantial
number of small entities.
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\183\ 5 U.S.C. 601-612.
---------------------------------------------------------------------------
103. Any Reliability Standards proposed by NERC in compliance with
this rulemaking will be considered by the Commission in future
proceedings. As part of any future proceedings, the Commission will
make determinations pertaining to the Regulatory Flexibility Act based
on the content of the Reliability Standards proposed by NERC.
VIII. Comment Procedures
104. The Commission invites interested persons to submit comments
on the matters and issues proposed in this notice to be adopted,
including any related matters or alternative proposals that commenters
may wish to discuss. Comments are due February 6, 2023 and Reply
Comments are due March 6, 2023. Comments must refer to Docket No. RM22-
12-000, and must include the commenter's name, the organization they
represent, if applicable, and their address in their comments.
105. The Commission encourages comments to be filed electronically
via the eFiling link on the Commission's website at <a href="http://www.ferc.gov">http://www.ferc.gov</a>. The Commission accepts most standard word processing
formats. Documents created electronically using word processing
software should be filed in native applications or print-to-PDF format
and not in a scanned format. Commenters filing electronically do not
need to make a paper filing.
106. Commenters that are not able to file comments electronically
must submit an original of their comments either by mail through the
United States Postal Service to: the Secretary of the Commission,
Federal Energy Regulatory Commission, 888 First Street NE, Washington,
DC 20426,\184\ or by any other method of delivery, including hand
delivery, to the Federal Energy Regulatory Commission, 12225 Wilkins
Avenue, Rockville, Maryland 20852.\185\
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\184\ 18 CFR 385.2001(a)(1)(i).
\185\ 18 CFR 385.2001(a)(1)(ii).
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107. All comments will be placed in the Commission's public files
and may be viewed, printed, or downloaded remotely as described in the
Document Availability section below. Commenters on this proposal are
not required to serve copies of their comments on other commenters.
IX. Document Availability
108. In addition to publishing the full text of this document in
the Federal Register, the Commission provides all interested persons an
opportunity to view and/or print the contents of this document via the
internet through the Commission's Home Page (<a href="http://www.ferc.gov">http://www.ferc.gov</a>). At
this time, the Commission has suspended access to the Commission's
Public Reference Room due to the President's March 13, 2020
proclamation declaring a National Emergency concerning the Novel
Coronavirus Disease (COVID-19).
109. From the Commission's Home Page on the internet, this
information is available on eLibrary. The full text of this document is
available on eLibrary in PDF and Microsoft Word format for viewing,
printing, and/or downloading. To access this document in eLibrary, type
the docket number excluding the last three digits of this document in
the docket number field.
110. User assistance is available for eLibrary and the Commission's
website during normal business hours from the Commission's Online
Support at 202-502-6652 (toll free at 1-866-208-3676) or email at
<a href="/cdn-cgi/l/email-protection#a2c4c7d0c1cdcccecbccc7d1d7d2d2cdd0d6e2c4c7d0c18cc5cdd4"><span class="__cf_email__" data-cfemail="9cfaf9eefff3f2f0f5f2f9efe9ececf3eee8dcfaf9eeffb2fbf3ea">[email protected]</span></a>, or the Public Reference Room at (202) 502-
8371, TTY (202)502-8659. Email the Public Reference Room at
<a href="/cdn-cgi/l/email-protection#7a0a0f1816131954081f1c1f081f14191f081515173a1c1f0819541d150c"><span class="__cf_email__" data-cfemail="08787d6a64616b267a6d6e6d7a6d666b6d7a676765486e6d7a6b266f677e">[email protected]</span></a>.
By direction of the Commission. Commissioner Danly is concurring
with a separate statement attached.
Issued: November 17, 2022.
Debbie-Anne A. Reese,
Deputy Secretary.
Note: The following appendix will not appear in the Federal
Register
Appendix A
NERC IBR Resources Cited in the NOPR
NERC Guidelines
NERC Guidelines referenced in this NOPR are available here:
<a href="https://www.nerc.com/comm/Pages/Reliability-and-Security-Guidelines.aspx">https://www.nerc.com/comm/Pages/Reliability-and-Security-Guidelines.aspx</a>.
NERC, Reliability Guideline: BPS-Connected Inverter-Based
Resource Performance (Sept. 2018), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Inverter-Based_Resource_Performance_Guideline.pdf</a> (IBR Performance
Guideline).
[[Page 74562]]
NERC, Reliability Guideline: Improvements to Interconnection
Requirements for BPS-Connected Inverter-Based Resources (Sept.
2019), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_IBR_Interconnection_Requirements_Improvements.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_IBR_Interconnection_Requirements_Improvements.pdf</a> (IBR Interconnection Requirements Guideline).
NERC, Reliability Guideline: Parameterization of the DER A
Model, (Sept. 2019), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_A_Parameterization.pdf</a>.
NERC, Reliability Guideline: DER Data Collection for Modeling in
Transmission Planning Studies, (Sept. 2020), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_Data_Collection_for_Modeling.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_DER_Data_Collection_for_Modeling.pdf</a> (IBR-DER
Data Collection Guideline).
NERC, Reliability Guideline: Performance, Modeling, and
Simulations of BPS-Connected Battery Energy Storage Systems and
Hybrid Power Plants (Mar. 2021), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_BESS_Hybrid_Performance_Modeling_Studies_.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/Reliability_Guideline_BESS_Hybrid_Performance_Modeling_Studies_.pdf</a>
(BESS Performance Modeling Guideline).
NERC White Papers
IRPTF white papers referenced in this NOPR are available here:
<a href="https://nerc.com/comm/PC/Pages/Inverter-Based-Resource-Performance-Task-Force.aspx">https://nerc.com/comm/PC/Pages/Inverter-Based-Resource-Performance-Task-Force.aspx</a>.
NERC, A Concept Paper on Essential Reliability Services that
Characterizes Bulk Power System Reliability (Oct. 2014), <a href="https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf">https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Concept%20Paper.pdf</a> (Essential Reliability Services Concept
Paper).
NERC, Resource Loss Protection Criteria Assessment Whitepaper
(Feb. 2018), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_RLPC_Assessment.pdf</a> (Resource Loss Protection Whitepaper).
NERC, Fast Frequency Response Concepts and Bulk Power System
Reliability Needs (Mar. 2020), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/Fast_Frequency_Response_Concepts_and_BPS_Reliability_Needs_White_Paper.pdf</a> (Fast Frequency Response White Paper).
NERC, IRPTF Review of NERC Reliability Standards White Paper
(Mar. 2020), <a href="https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf">https://www.nerc.com/pa/Stand/Project202104ModificationstoPRC0022DL/Review_of_NERC_Reliability_Standards_White_Paper_062021.pdf</a>
(Reliability Standards Review White Paper).
NERC, San Fernando Disturbance Follow-Up White Paper (June
2021), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/IRPWG_San_Fernando_Disturbance_Follow-Up_Paper%20">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/IRPWG_San_Fernando_Disturbance_Follow-Up_Paper%20</a>(003).pdf (San
Fernando Disturbance White Paper).
NERC, Utilizing the Excess Capability of BPS-Connected Inverter-
Based Resources for Frequency Support (Sept. 2021), <a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_IBR_Hybrid_Plant_Frequency_Response.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_IBR_Hybrid_Plant_Frequency_Response.pdf</a> (Frequency
Support White Paper).
NERC, Odessa Disturbance Follow-up White Paper (Oct. 2021),
<a href="https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf">https://www.nerc.com/comm/RSTC_Reliability_Guidelines/White_Paper_Odessa_Disturbance_Follow-Up.pdf</a> (Odessa Disturbance
White Paper).
NERC Reports
NERC, 2013 Long-Term Reliability Assessment (Dec. 2013),
<a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/2013_LTRA_FINAL.pdf</a> (2013 LTRA Report).
NERC, Distributed Energy Resources: Connection Modeling and
Reliability Considerations (Feb. 2017), <a href="https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf">https://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/Distributed_Energy_Resources_Report.pdf</a> (NERC DER Report).
NERC, 2020 Long Term Reliability Assessment Report (Dec. 2020),
<a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2020.pdf</a> (2020 LTRA Report).
NERC, 2021 Long Term Reliability Assessment Report (Dec. 2021),
<a href="https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf">https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_LTRA_2021.pdf</a> (2021 LTRA Report).
NERC Technical Reports
NERC technical reports referenced in this NOPR are available
here: <a href="https://nerc.com/comm/PC/Pages/Inverter-Based-Resource-Performance-Task-Force.aspx">https://nerc.com/comm/PC/Pages/Inverter-Based-Resource-Performance-Task-Force.aspx</a>.
NERC, Technical Report, BPS-Connected Inverter-Based Resource
Modeling and Studies (May 2020), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_IBR_Modeling_and_Studies_Report.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/IRPTF_IBR_Modeling_and_Studies_Report.pdf</a> (Modeling and Studies
Report).
NERC and WECC, WECC Base Case Review: Inverter-Based Resources
(Aug. 2020), <a href="https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf">https://www.nerc.com/comm/PC/InverterBased%20Resource%20Performance%20Task%20Force%20IRPT/NERC-WECC_2020_IBR_Modeling_Report.pdf</a> (Western Interconnection (WI) Base
Case IBR Review).
NERC Major Event Reports
NERC event reports referenced in this NOPR are available here:
<a href="https://www.nerc.com/pa/rrm/ea/Pages/Major-Event-Reports.aspx">https://www.nerc.com/pa/rrm/ea/Pages/Major-Event-Reports.aspx</a>.
NERC, 1,200 MW Fault Induced Solar Photovoltaic Resource
Interruption Disturbance Report (June 2017), <a href="https://www.nerc.com/pa/rrm/ea/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_Interruption_Final.pdf">https://www.nerc.com/pa/rrm/ea/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_/1200_MW_Fault_Induced_Solar_Photovoltaic_Resource_Interruption_Final.pdf</a> (Blue Cut Fire Event Report) (covering the Blue Cut Fire event
(August 16, 2016)).
NERC and WECC, 900 MW Fault Induced Solar Photovoltaic Resource
Interruption Disturbance Report (Feb. 2018), <a href="https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf">https://www.nerc.com/pa/rrm/ea/October%209%202017%20Canyon%202%20Fire%20Disturbance%20Report/900%20MW%20Solar%20Photovoltaic%20Resource%20Interruption%20Disturbance%20Report.pdf</a> (Canyon 2 Fire Event Report) (covering the Canyon 2
Fire event (October 9, 2017)).
NERC and WECC, April and May 2018 Fault Induced Solar
Photovoltaic Resource Interruption Disturbances Report (Jan. 2019),
<a href="https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/April_May_2018_Fault_Induced_Solar_PV_Resource_Int/April_May_2018_Solar_PV_Disturbance_Report.pdf</a> (Angeles Forest and
Palmdale Roost Events Report) (covering the Angeles Forest (April
20, 2018) and Palmdale Roost (May 11, 2018) events)/
NERC and WECC, San Fernando Disturbance, (Nov. 2020), <a href="https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/San_Fernando_Disturbance_Report.pdf</a>
(San Fernando Disturbance Report) (covering the San Fernando event
(July 7, 2020)).
NERC and Texas RE, Odessa Disturbance (Sept. 2021) <a href="https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/Odessa_Disturbance_Report.pdf</a>
(Odessa Disturbance Report) (covering events in Odessa, Texas on May
9, 2021 and June 26, 2021).
NERC and WECC, Multiple Solar PV Disturbances in CAISO (April
2022), <a href="https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/NERC_2021_California_Solar_PV_Disturbances_Report.pdf</a> (2021 Solar PV
Disturbances Report) (covering four events: Victorville (June 24,
2021); Tumbleweed (July 4, 2021); Windhub (July 28, 2021); and Lytle
Creek (August 26, 2021)).
NERC and Texas RE, March 2022 Panhandle Wind Disturbance Report
(August 2022), <a href="https://www.nerc.com/pa/rrm/ea/Documents/Panhandle_Wind_Disturbance_Report.pdf">https://www.nerc.com/pa/rrm/ea/Documents/Panhandle_Wind_Disturbance_Report.pdf</a> (Panhandle Report) (covering
the Texas Panhandle event (March 22, 2022)).
NERC Alerts
NERC Alerts referenced in this NOPR are available here: <a href="https://
[…truncated; see source link]Indexed from Federal Register on December 6, 2022.
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