Prc-30-1

PRC-030-1 – Unexpected Inverter-Based Resource Event Mitigation

A. Introduction
1.

Title:

Unexpected Inverter-Based Resource Event Mitigation

2.

Number:

PRC-030-1

3.

Purpose:

Identify, analyze, and mitigate unexpected Inverter-Based Resource (IBR)
change of power output.

4.

Applicability:
4.1. Functional Entities:
4.1.1. Generator Owner
4.2. Facilities:
4.2.1. Bulk Electric System (BES) Inverter-Based Resources; and
4.2.2. Non-BES Inverter-Based Resources that either have or contribute to an
aggregate nameplate capacity of greater than or equal to 20 MVA,
connected through a system designed primarily for delivering such
capacity to a common point of connection at a voltage greater than or
equal to 60 kV.

5.

Effective Date: See Implementation Plan for PRC-030-1

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PRC-030-1 – Unexpected Inverter-Based Resource Event Mitigation

B. Requirements and Measures
R1. Each applicable Generator Owner shall implement a documented process to identify
any complete facility loss of output, or changes in Real Power output that are at least
20 MW and at least 10% of the plant's gross nameplate rating, occurring within a 4
second period. Changes in Real Power for the following are excluded: [Violation Risk
Factor: Medium] [Time Horizon: Operations Planning]
•

Changes associated with intermittent primary energy source availability, created
by changes such as variation in wind speed and solar irradiance;

•

Resource dispatch, resource ramping, planned outages, or planned resource
testing;

•

A Transmission or collection system loss that, by configuration, disconnects the
Inverter-Based Resource generator; or

•

Real Power reduction due solely to a Protection System Misoperations being
analyzed and corrected under PRC-004 Reliability Standard.

M1. Each applicable Generator Owner shall have evidence which includes but is not limited
to: (1) the documented process for detecting changes in output as described in
Requirement R1, (2) evidence to demonstrate implementation of its documented
process, (3) actual data recordings, and (4) identification of gross nameplate rating.
R2. Each applicable Generator Owner, within 90 calendar days of a Real Power change
event pursuant to Requirement R1 or following a request from its associated
Reliability Coordinator, Balancing Authority, or Transmission Operator that identified a
Disturbance and a change in the Inverter-Based Resource(s) Real Power output, shall:
[Violation Risk Factor: Medium] [Time Horizon: Operations Planning]
2.1. Analyze its Inverter-Based Resource facility performance during the event,
including:
2.1.1. Determine the root cause(s) of change(s) in Real Power output;
2.1.2. Document the facility’s Ride-through performance including Reactive
Power response during the event;
2.1.3. Assess any performance issues identified and if corrective actions are
needed; and
2.1.4. Determine the applicability of the root cause(s) to the Generator Owner’s
other Inverter-Based Resource facilities.
2.2. Upon request, provide the analysis results to the requesting associated
Reliability Coordinator, Balancing Authority, or Transmission Operator.
M2. Each applicable Generator Owner shall have dated documentation of the required
analysis developed in accordance with Requirement R2. Evidence may include, but is
not limited to: (1) an analysis report, (2) actual data recordings or derivations, (3)
documents describing the device specification and device configuration or settings,
and (4) plant configuration.
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PRC-030-1 – Unexpected Inverter-Based Resource Event Mitigation

R3. If performance issues and a need for corrective actions were identified in Requirement
R2 Part 2.1.3, each applicable Generator Owner shall, within 60 calendar days of
completing the analysis in Requirement R2, develop one of the following and provide
it to the associated Reliability Coordinator, Balancing Authority, and Transmission
Operator: [Violation Risk Factor: Medium] [Time Horizon: Operations Planning]
•

A Corrective Action Plan (CAP) for the identified Inverter-Based Resource(s),
including other applicable facilities owned by the Generator Owner as identified in
Requirement R2 Part 2.1.3; or

•

A technical justification that addresses why corrective actions will not be
implemented.

M3. Each applicable Generator Owner shall have dated evidence (electronic or hardcopy
format) that demonstrates it developed a CAP or a technical justification, and
evidence of transmittal to the Reliability Coordinator, Balancing Authority, and
Transmission Operator in accordance with Requirement R3.
R4. Each applicable Generator Owner shall, for each of its Corrective Action Plans
developed pursuant to Requirement R3: [Violation Risk Factor: Medium] [Time
Horizon: Operations Planning, Long-term Planning]
4.1. Implement the CAP;
4.2. Update the CAP if actions or timetables change; and
4.3. Notify each associated Reliability Coordinator if CAP actions or timetables
change and when the CAP is completed.
M4. Acceptable evidence may include, but is not limited to, dated documentation such as
CAPs, project or work management program records, settings sheets, work orders,
maintenance records, communication with equipment manufacturers, and
communication with each associated Reliability Coordinator that documents the
implementation, updating, or completion of a CAP in accordance with Requirement
R3.

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PRC-030-1 – Unexpected Inverter-Based Resource Event Mitigation

C. Compliance
1.

Compliance Monitoring Process
1.1. Compliance Enforcement Authority: “Compliance Enforcement Authority”
means NERC or the Regional Entity, or any entity as otherwise designated by an
Applicable Governmental Authority, in their respective roles of monitoring
and/or enforcing compliance with mandatory and enforceable Reliability
Standards in their respective jurisdictions.
1.2. Evidence Retention: The following evidence retention period(s) identify the
period of time an entity is required to retain specific evidence to demonstrate
compliance. For instances where the evidence retention period specified below
is shorter than the time since the last audit, the Compliance Enforcement
Authority may ask an entity to provide other evidence to show that it was
compliant for the full-time period since the last audit.
The applicable entity shall keep data or evidence to show compliance as
identified below unless directed by its Compliance Enforcement Authority to
retain specific evidence for a longer period of time as part of an investigation.
•

The Generator Owner shall keep data or evidence of Requirement R1, and
R2, Measure M1, and M2 for 36 calendar months following the completion
of each Requirement.

•

The Generator Owner shall retain evidence of Requirement R3, Measure
M3, including any supporting analysis per Requirements R2 and R3, for a
minimum of 36 calendar months following completion of each CAP,
completion of each evaluation, and completion of each declaration.

•

The Generator Owner shall retain evidence of Requirement R4, Measure
M4 for a minimum of 36 calendar months following completion of each
CAP.

1.3. Compliance Monitoring and Enforcement Program: As defined in the NERC
Rules of Procedure, “Compliance Monitoring and Enforcement Program” refers
to the identification of the processes that will be used to evaluate data or
information for the purpose of assessing performance or outcomes with the
associated Reliability Standard.

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PRC-030-1 – Unexpected Inverter-Based Resource Event Mitigation

Violation Severity Levels
Violation Severity Levels

R#

Lower VSL

Moderate VSL

High VSL

Severe VSL

R1.

N/A

N/A

N/A

The responsible entity failed to
implement a documented
process to identify changes in
Real Power output in
accordance with Requirement
R1.

R2.

The responsible entity
performed an analysis in
accordance with Requirement
R2, but in more than 90
calendar days but less than
120 calendar days of an event
or receiving a request.

The responsible entity
performed an analysis in
accordance with Requirement
R2, but in 120 or more
calendar days but less than
150 calendar days of an event
or receiving a request.

The responsible entity
performed an analysis in
accordance with Requirement
R2, but in 150 or more
calendar days but less than
180 calendar days of an event
or receiving a request.
OR
The responsible entity
performed the analysis in
Requirement R2 but failed to
address Part 2.1.1 or Part
2.1.4.
OR
The responsible entity failed to
provide the analysis results
from the requesting entity in
accordance with Requirement
R2, Part 2.2.

The responsible entity
developed an analysis in
accordance with Requirement
R2, but in 180 calendar days or
more of an event or receiving
a request.
OR
The responsible entity
performed the analysis in
Requirement R2 but failed to
address Part 2.1.1 and Part
2.1.4.
OR
The responsible entity failed to
document the facility’s Ridethrough performance in
accordance with Requirement
R2, Part 2.1.2
OR
The responsible entity failed to
determine the applicability of
other Inverter-Based Resource
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PRC-030-1 – Unexpected Inverter-Based Resource Event Mitigation

R#

Violation Severity Levels
Lower VSL

Moderate VSL

High VSL

Severe VSL
facilities in accordance with
Requirement R2, Part 2.1.4.

R3.

The responsible entity failed to
develop a CAP or provide a
technical justification
addressing why no corrective
actions will be implemented
within 60 calendar days, but
provided it within 90 calendar
days.

The responsible entity failed to
develop a CAP or provide a
technical justification
addressing why no corrective
actions will be implemented
within 90 calendar days, but
provided it within 120
calendar days.

The responsible entity failed to
develop a CAP or provide a
technical justification why no
corrective actions will be
implemented within 120
calendar days, but provided it
within 150 calendar days
OR
The developed CAP did not
include corrective actions for
other facilities owned by the
Generator Owners as
identified in Requirement R2
Part 2.1.3, if necessary.
OR
The developed CAP or
technical justification was not
provided to the associated
Reliability Coordinator,
Balancing Authority, and
Transmission Operator.

The responsible entity failed to
develop a CAP or provide a
technical justification
addressing why no corrective
actions will be implemented,
within 150 calendar days.

R4.

The responsible entity
implemented, but failed to
update a CAP, when actions or
timetables changed, in
accordance with Requirement
R4.

N/A

N/A

The responsible entity failed to
implement a CAP in
accordance with Requirement
R4.

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PRC-030-1 – Unexpected Inverter-Based Resource Event Mitigation

D. Regional Variances
None.

E. Associated Documents
Implementation Plan.

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PRC-030-1 – Unexpected Inverter-Based Resource Event Mitigation

Version History
Version
1

Date
October 8, 2024

Action

Change
Tracking

Adopted by NERC Board of Trustees

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