On March 17, 2016, the Federal Energy Regulatory Commission (“FERC” or the “Commission”) issued an order approving Reliability Standard PRC-026-1 (Relay Performance During Stable Power Swings). According to the Commission, PRC-026-1 is “designed to ensure that applicable entities use protective relay systems that can differentiate between faults and stable power swings.” The Commission also approved the proposed violation risk factors, violation severity levels, and implementation plan for PRC-026-1. Under the approved implementation plan, Requirement R1 of PRC-026-1 will become effective 12 months after Commission approval, and Requirements R2, R3, and R4 will become effective 36 months after Commission approval.

PRC-026-1 was developed by the North American Electric Reliability Corporation (“NERC”) in response to a Commission directive in Order No. 733—a 2010 order approving Reliability Standard PRC-023-1 (Transmission Relay Loadability). In Order No. 733, FERC noted a specific finding of the investigations that followed the 2003 Northeast Blackout, which determined, among other things, that the cascading outage during the event was accelerated by certain relays that could not distinguish between a dynamic, but stable, power swing and an actual fault. As a result, these relays unnecessarily tripped certain bulk electric system facilities out of service during the event. Accordingly, the Commission directed NERC to develop a Reliability Standard to address undesirable relay operation due to stable power swings. NERC submitted its petition for approval of PRC-026-1 on December 31, 2014.

In its March 17, 2016 order, the Commission approved PRC-026-1 as proposed by NERC. The Commission found that while NERC’s proposed Reliability Standard did not require the phase-out of all relays that cannot differentiate between faults and stable power swings—an approach the Commission had suggested in Order No. 733—it nonetheless addressed the Commission’s directive in Order No. 733 by providing specific measures to mitigate the unnecessary tripping of bulk electric system elements in response to stable power swings. The Commission therefore found “that Reliability Standard PRC-026-1’s approach is an equally effective and efficient method to achieve the reliability goal underlying the Commission’s directive in Order No. 733.”

A copy of the Commission’s order may be found here.