2 System Performance Criteria - TPL-001-WECC-RBP-2 SAR initiated in response to RCWG recommendations to RPICTier 1 analysis conducted by RSEvaluate and recommend how document should be CategorizedDependencies on other effortsScope of drafting effortTimelineRecommendation to WSC June 2013Retirement of WR1, WR2, WR4, WR5Project WECC-0100 SDT formed under WSC to determine disposition of WR3 and respond to comments from ballot.OverviewFirst three items are updates on current efforts.Last item was discussed and RS is defining functions to respond to this NERC effort.
3 System Performance Criteria - TPL-001-WECC-RBP-2 RS prepared the document “WECC-0100 Tier 1 Evaluation and Recommendations” dated May 31, 2013Standard or CriterionReferenceRecommendationSupporting DocumentationFAC-010/-011 Regional DifferencesNERCEliminateWhite PaperN-2 for Adjacent Circuits on Separate StructuresWR1.1FAC-010/-011 White PaperG-2 not addressed by NERC TPL Category CWR1.2Eliminate or ReviseMultiple Bus Sections (B-2)WR1.3Less stringent than existing and future NERC TPL requirementsTable W-1 PerformanceAdjustment with WECC Board ApprovalWR1.4Make Table W-1 a Guideline for future use with NERC TPL R5 when it becomes effectiveCoordinate with WECC RC SOL Methodology which provides minimum acceptable performance criteria for each TOP.Voltage StabilityWR3RS divided as to whether to make a standard or a guideline; this should be resolved by the drafting teamCoordinate with WECC RC SOL Methodology to ensure common definition for SOLs and IROLsUnsuccessful ReclosingWR4Will be covered by future NERC TPL RActual Cascading EventsWR5Actual events are investigated by WECC/NERC/FERC; recommendations from these investigations address this requirement.Performance Category Upgrade Request ProcessTied to the outcome of WR1.1 and the FAC-010/-011 Regional Differences
4 TPL-001-WECC-RBP WR1Requirement WR1 requires Planning Coordinators and Transmission Planners to comply with the WECC Disturbance Performance Table W-1 of allowable effects on other systems for all NERC TPL planning events.Discussion –New NERC TPL Table 1 replaces Cat. A-D with P0-7. Expands contingency simulations and required performance.NERC TPL requirement R5 will require PC/TP’s to have criteria for ... transient voltage response.Table W-1 more of a guideline today, 57 exceptions.RS will be developing Vdip Guideline PC/TP’s will be able to use for NERC TPL R5.
5 Discussion – TPL-001-WECC-RBP-2 ... WR1-R1.1 The NERC Category C.5 initiating event of a single-line-to- ground fault with normal clearing shall also apply to the common mode contingency of two Adjacent Transmission Circuits on separate towers — unless the Mean Time Between Failure (MTBF) is determined to be greater than 30 years (i.e., outage frequency is less than outages per year).Discussion –Double-circuit line outage rate 1.8 times two circuits on separate structures on common ROW.Outage rate not on common ROW 1.4 times on common ROW.Two circuits not on common ROW covered by NERC Table 1.Included in FAC-010-R2.1 Section E R1.1.5Recommendation to Retire
6 Discussion Continued – TPL-001-WECC-RBP WR1-R1.1Discussion Continued –Table 1Western Interconnection Average DataCircuits on Common StructureCircuits on Common Right-of-Way Separate StructureCircuits not on Common ROW or StructureTransmission Miles8,82214,78251,649Number of Events2422103No. of Outages/100 miles of line0.2710.1470.207Outage comparison of circuits on common ROW and/or structures when 2 or more circuits went out of service.From WECC Transmission Reliability Data.
7 TPL-001-WECC-RBP WR1-R1.2The common mode simultaneous outage of two generator units connected to the same switchyard, not addressed by the initiating events in NERC Category C, shall not result in cascading.Discussion –Common mode outage in the substation (breaker failures) already covered by NERC Table 1.Interpretation is confusing. No known common mode outage between units on the generator side.Included in FAC-010-R2.1 Section E R1.1.6.Recommendation to Retire
8 TPL-001-WECC-RBP WR1-R1.3The loss of multiple bus sections, as a result of a failure or delayed clearing of a bus tie or bus sectionalizing breaker, shall meet the performance specified for Category D of Table W-1.Discussion –Less stringent that existing NERC TPL-003, C.2 and C.9.More definitive performance requirement in NERC TPL-001-4, Table 1, P.4.Recommendation to Retire.
9 TPL-001-WECC-RBP WR1-R1.4For contingencies involving existing or planned facilities, the Table W-1 performance category can be adjusted based on actual or expected performance (e.g., event outage frequency and consideration of impact) after receiving Board approval to change the Performance Level Adjustment Record.Discussion –Historically used to adjust WR1.1 contingencies from Cat. C to D. Essentially an exception process for WR1.1.Requirement for WECC Board approval retained in “Seven Step Process for Performance Category Upgrade Request “.Recommendation to Retire.
10 TPL-001-WECC-RBP WR2Individual systems or a group of systems may apply requirements that differ from specific requirements in Table W-1 for internal impacts. If the individual requirements are less stringent, other systems are permitted to have the same impact on that part of the individual system for the same category of disturbance. If these requirements are more stringent, these requirements may not be imposed on other systems.Discussion –Policy statement tied to Table W-1, not a measurable Standard.NERC TPL Requirement R5 requires PC/TP’s to have criteria for ... transient voltage response. Results in similar study results to the intent of WR2.Recommendation to Retire.
11 TPL-001-WECC-RBP WR3Reactive power resources, with a balance between static and dynamic characteristics, shall be planned and distributed throughout the interconnected transmission systems to ensure system performance... defines real power margin for Category A, B, and C contingencies.Discussion –The RS continues to discuss whether to reclassify this requirement as a Regional Standard or as a Guideline. Project WECC-0100 SDT formed to formulate a decision that will be balloted for wider approval.Recommendation to form SDT.
12 TPL-001-WECC-RBP WR4The Planning Coordinators and Transmission Planners shall meet the same performance category for unsuccessful reclosing, as that required for the initiating disturbance without reclosing.Discussion –Addressed by NERC TPL-001-4, R that states “The analysis shall include the impact of subsequent: Successful high speed reclosing and unsuccessful high speed reclosing into a fault where high speed reclosing is utilized.”Recommendation to Retire.
13 TPL-001-WECC-RBP WR5For any event that has actually resulted in cascading, action must be taken so that future occurrences of the event will not result in cascading; or it must demonstrate that the Mean Time Between Failure (MTBF) is greater than 300 years (frequency less than outages/year) and approved by PCC.Discussion –NERC performance standards are deterministic and provide specific performance requirements for specific events.Event reporting required by NERC EOP-004. Actual events are investigated by WECC, NERC, FERC or some combination.Corrective actions required by NERC TOP regardless of MTBF.Recommendation to Retire.
14 Review of Action ItemsAction ItemStatusCompletion Date
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