The standard authorization request (SAR) was prepared by the Inverter-Based Resource Performance Task Force (IRPTF), based on disturbance analyses and the development of the PRC-024-2 Gaps Whitepaper. The IRPTF identified potential modifications to PRC-024-2 to “ensure inverter-based generator owners, operators, developers and equipment manufacturers understand the intent of the standard.” (See NERC to Try Again on Inverter Rules.)

One of the most significant changes is in Section 4.1.2., where NERC proposes expanding applicability to include transmission owners “that own a bulk electric system (BES) generator step-up (GSU) transformer or collector transformer.”

It also requires inverters not trip or “enter momentary cessation” — an interruption in their injection of current into the grid — within the “no trip zone,” except for “documented and communicated regulatory or equipment limitations.”

Slight Change to Standards Efficiency Review Retirements

The standard drafting team for Project 2018-03 Standard Efficiency Review Retirements informed the committee of a need for a minor tweak to existing rules.

Reliability standard INT-009-2.1 Requirement R1 references standard INT 010-2, which has been selected for retirement. The team will remove references to INT 010-2 from the remaining standard to avoid confusion.

The drafting team arose from NERC’s 2017 Standards Efficiency Review (SER) to consider the retirements of all or part of more than 30 reliability standards. (See “Team Gets Go Ahead on Standards Retirement Review” in NERC Standards Committee Briefs: Jan. 23, 2019.)

Standards Drafting Team Set for Response to FERC Order 851

The committee unanimously approved nine nominees for a standards drafting team to respond to the directives in FERC Order 851, which approved NERC’s revised geomagnetic disturbance standard.

NERC created Reliability Standard TPL-007-2 (Transmission System Planned Performance for Geomagnetic Disturbance Events) in response to FERC’s directives to improve how its initial GMD standard, approved in 2016, addressed the risks from “locally enhanced” events.

Order 851, approved in November, directed NERC to revise the standard further to require the implementation of corrective action plans for responding to vulnerabilities to “supplemental” GMD events and to authorize case-by-case extensions of deadlines on corrective action plans. (See Revised NERC GMD Standard Approved.)

– Christen Smith