ERCOT Makes Progress on Subsynchronous Resonance Issues

ERCOT Makes Progress on Subsynchronous Resonance Issues

Apr 7, 2017

by Margarita Fournier; Copyright 2016 by Competitive Assets, LLC.  All rights reserved

Since at least 2013, the PUCT, ERCOT, and stakeholders have been working on issues related to Subsynchronous Resonance (SSR). In Aug. 2013, ERCOT filed Nodal Protocol Revision Request NPRR562, noting that “SSR is a potentially harmful phenomenon, involving coincident oscillation between two or more Transmission Elements or Generation Resources at frequencies lower than the normal operating frequency (60Hz) of the ERCOT System,” and that its system “has recently become more vulnerable to SSR because of the introduction of series capacitors for voltage support.” In the stakeholder debates, some aspects of the proposed solution elicited opposition (e.g., who pays for mitigation efforts), which in time led to the PUCT opening two related projects and holding workshops.

On 4/6/17, ERCOT filed with the Commission an update, announcing that NPRR562 had been approved by the Protocol Revision Subcommittee, and noting that if it were approved by the ERCOT Board (likely in June), “then ERCOT believes that it will have established appropriate planning, operational, and entity responsibility rules to holistically address the potential for SSR vulnerability in the ERCOT Region. ERCOT further believes that the Commission would not need to take any additional action on this matter.”

 Back to Texas Electric News Clips

  • Competitive Assets

    provides information and consulting for the Texas electric utility industry and is the information source relied upon by many retail electric providers, cooperatives, municipalities, generators, power marketers, brokers, aggregators, wires companies, PUCT staff, ERCOT staff, Texas legislators and staff, FERC staff, metering companies, members of the financial community, consumer representatives, and other parties interested in the Texas electric industry..

    For more, click here to visit

  • News Services provided by Competitive Assets

    Texas Electric Watch

    Texas Electric Policy News

    ERCOT Monitor Reports


    For a free trial subscription to any of these 3 news services, please send an email to freetrial. If you are interested in subscribing any of these 3 news services, please click here or call Competitive Assets at 512-581-0151

  • Texas Electric News Daily Email Sign Up

    Enter your name and email address to receive daily Texas Electric News Clip emails


    By submitting this form, you are granting: Competitive Assets LLC, 494 Hwy 71 W, Bastrop, TX, 78602, permission to email you. You may unsubscribe via the link found at the bottom of every email. (See our Email Privacy Policy ( for details.) Emails are serviced by Constant Contact.
  • Special Reports by Competitive Assets

    How to Prepare Confidential Filings at the PUCT


    For more information about this special report, please click here or go to CA Store-Special Reports page.

  • ERCOT Monitor Reports---New Issue


    ERCOT's Technical Advisory Committee (TAC) Meeting 8/25/16

    At the August Technical Advisory Committee meeting, participants considered a number of revision requests, heard an update on the Smart Meter Texas efforts, and noted the growth of unregistered distributed generation in several load zones.

    For more about the meeting, Please click here.

  • Other Services provided by Competitive Assets

    ERCOT TDU Rate Updates

    Provides updates of approved rates for TDUs in ERCOT in a spreadsheet format, updated twice per month

    If you are interested in subscribing this service, please click here or call Competitive Assets at 512-581-0151