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PGRR #25 · Revision Request

PGRR025  Addition of Criteria for Autotransformer Unavailability

Approved sponsor PLWG posted 2012-11-02 ercot.com
ReasonAt its 9/13/12 meeting, ROS directed the Planning Working Group (PLWG) to modify the ERCOT planning criteria to add ERCOT System performance testing associated with the unavailability of an autotransformer. High voltage autotransformers are typically known to have long lead delivery times ranging anywhere between one year to two years. The outage and subsequent long-term unavailability of autotransformers can impact ERCOT System reliability and needs to be accounted for in planning studies. The proposed North American Electric Reliability Corporation (NERC) Reliability Standard TPL-001-2, Transmission System Planning Performance Requirements, R.2.1, 2.1.5 requires Entities to assess the impact of the possible unavailability of major transmission equipment having a lead time of one year or more (such as a transformer) on system performance. Proposed performance testing requirements are limited to paragraphs (1)(c) and 1(d) and line 3 of Table 1, ERCOT-specific Reliability Performance Criteria, of Section 4.1.1.2.
Created2012-12-04
Sections Affected
4.1.1.2
Summary
This Planning Guide Revision Request (PGRR) adds testing and performance requirements to the ERCOT reliability criteria for the unavailability of any 345/138 kV autotransformer.
Timeline