31st Team Meeting Purpose What are we addressing? NERC Standard WRS1. New TPL-001Process so far, how we got here….
41st Team Meeting Purpose The purpose of this request is to revise the current TPL – (001 thru 004) – WECC – 1 – CR - System Performance Criteria requirement WRS1.1 to permit the more efficient use of rights-of-way while promoting the use of separate tower instead of multi-circuit towers and maintaining an acceptable level of reliability for the Western Interconnection. The use of separate towers is preferred to multi-circuit towers.
71st Team Meeting Current Criteria within WECC: WRS1. In addition to NERC Table 1, PAs and TPs shall comply with the WECC Disturbance-Performance Table, Table W-1, of Allowable Effects on Other Systems contained in this section when planning the Western Interconnection. Table W-1 does not apply internal to a Transmission Operator area.WECC Table W-1 – Voltage & Frequency Dip
81st Team MeetingWRS1.1.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 Circuits on separate towers unless the event frequency is determined to be less than one in thirty years.
111st Team Meeting Definitions of: Common Corridor = Contiguous ROW or two parallel ROWs with Structure centerline separation less than the longest span of the two transmission circuits at the point of separation or 500 feet, whichever is greatest, between the two circuits.Adjacent Transmission Circuits = Transmission circuits within a Common Corridor with no other transmission circuits between them.
121st Team Meeting New TPL-001 P7: Multiple Contingency (Common Structure)The loss of:Any two adjacent (vertically or horizontally) circuits on common structure 11Loss of a bipolar DC lineSLGEHV, HV
131st Team Meeting Continued from previous slide… YES Interruption of Firm Transmission Service Allowed 4YESNon-Consequential Load Loss Allowed
141st Team Meeting RS began process… Based on White Paper written by RS Process so far…Numerous discussions at RS throughout 2009Presented to PCC & OC twice last yearLively discussion with feedback from one end to the otherRS began process…Based on White Paper written by RS2 supporting documents, SWAT & WIA
151st Team MeetingOn February 26, 2010 the Standards Request Routing Committee (SRRC) met via telephone to discuss assignment of WECC-0071, System Performance Criteria. The SRRC concluded the Request was in scope and assigned drafting to the PCC. Ms. Cabbell, chair of the PCC, assigned the drafting task to the Reliability Subcommittee with augmentation to be sought by Mr. Watkins, chair of the OC, to include operators from the OC. If additional team expertise is needed Ms. Cabbell and her assigned drafting team chair are authorized to augment the team members as needed.
161st Team MeetingComments received during the 30 day comment period – abridged-
171st Team Meeting Armie Perez, ZGlobal In the evaluation of the loss of lines in a ROW, my recollection is that the probability of N-2 is not really that much greater for 2 lines on the same tower versus separate towers. This should be confirmed.
181st Team Meeting John Lucas, APS PCC should be assigned as the lead committeeThis is very timely and is urgently needed.
191st Team Meeting Bill Pascoe, TransWest, LLC The request, as drafted, focuses narrowly on a particular common corridor issue for Category C events. TWE believes that common corridor issues related to Category D events are also important to the appropriate balancing of reliability and environmental/land use impacts for major new transmission lines being planned in WECC. TWE requests that the drafting team be directed to also consider common corridor issues for Category D events.
201st Team Meeting Chuck Matthews, (Denise Koehn) BPA 1. Although the primary purpose is revision of requirement WRS1.1, the purpose should be expanded to include the following, "In addition, other requirements in WECC-0071 may need to be revised based on other NERC Standards drafting efforts." One reason for expanding this revision request is to provide more consistent terminology with the NERC Standards.
211st Team Meeting Chuck Matthews, BPA continued The "Proposed WRS1.1" in the section "Detailed Description" should be removed and the first paragraph in that section changed accordingly. The proposal seems to presuppose the outcome of the revised criteria.
221st Team Meeting Darcy O’Connell, CAISO The California ISO supports Brian Keel's (SRP) suggestion on Revised TPL 1-4 project to remove restriction imposed by WECC under its requirement WRS1.1 to make it consistent with the NERC requirement.
231st Team Meeting Potential Benefits of changing Criterion: Potentially higher ratings on WRS1.1 limited PathsHigher values of remote generationAllow placing circuits within current definition without requirementsReduce environmental impacts, less ROW overallConsolidation of facilities, construction and maintenanceIncreased use of existing ROWs to a corridor
241st Team Meeting Author confession: Proposed WRS1.1: The NERC Category C.5 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 30 years. The fault to be used for this study shall be a single line-to-ground fault. The performance requirements of NERC Table 1 shall apply to this contingency and WECC Table W-1 shall not apply.Proposed to get started!Team develops best solution for all of WECC!!