WECC Operating Committee and Planning Coordinating Committee Brian K. Keel Chair – Reliability Subcommittee June 18 & 19, 2009 WECC Reliability Subcommittee Report

RS Report WECC WRS1.1 Criterion & NERC FAC-010 & FAC-011 LVRT Criterion TADS/TRD update

WECC WRS1.1 & FAC-010/FAC-011 TPL-( )-WECC-1-CR – WRS1. In addition to NERC Table 1, comply with WECC Table W-1 of Allowable Effects on Other Systems, Table W-1 does not apply internally to a TO. – Table W-1 => Voltage, Frequency, Post-Transient & Outage Freq. – WRS1.1. The NERC Category C.5 initiating event of a non – three phase fault with normal clearing shall also apply to the common mode contingency of two Adjacent Transmission Circuits on separate towers unless the event frequency is determined to be less than one in thirty years.

WECC WRS1.1 & FAC-010/FAC-011 Should this Criterion be changed/removed? Only NERC region applying corridor outage performance criteria Reliability Performance Evaluation Work Group – 4 Circuits have successful Performance Category Upgrade Requests

WECC WRS1.1 & FAC-010/FAC-011 Application of NERC Table 1 Application of WECC Table W-1 (not internal system Attempt to change as WECC Criterion? – NERC Table I – WECC Table W-1

WECC WRS1.1 & FAC-010/FAC-011 Ramifications if changed: – Potentially higher Ratings on Some WECC Rated Paths Some TTC values – Dependant on which is limit – Potentially higher remote generation transfers – Allow placing of circuits within the current definition of a corridor without requirements

WECC WRS1.1 & FAC-010/FAC-011 – Remove industry justification of having the criterion to keep separation – May be forced to accommodate more circuits closer together Reliability decrease? Increase impact on other WECC Members

WECC WRS1.1 & FAC-010/FAC-011 RS recommends: – RS Request to Revise or Develop a Standard Step 1 of Process for Developing and Approving WECC Standards SAR Draft Team to explore changing the Criterion

WECC WRS1.1 & FAC-010/FAC-011 FAC-010 and FAC-011 – System Operating Limits Methodology for the Planning Horizon – System Operating Limits Methodology for the Operating Horizon Regional Variance E – Simultaneous permanent phase to ground Faults on different phases of two adjacent circuits on a multiple circuit tower, with Normal Clearing. If multiple circuit towers are used for station entrance and exit purposes…

WECC WRS1.1 & FAC-010/FAC-011 Fault application needs clarity Different phases, potential numerous combinations SLG A to C same results as SLG A to A

WECC WRS1.1 & FAC-010/FAC-011 RS recommends: – Asking NERC for interpretation of the FAC-010 and FAC-011 Regional Variance E Returned to WECC Suggest alteration of language for clarity and ease of study in Planning and Operating Horizons