WECC Experience in the Collection of Transmission Common Mode and Dependant...
Transcript of WECC Experience in the Collection of Transmission Common Mode and Dependant...
WECC Experience in the Collection of Transmission Common – Mode
and Dependant Outages
Brian Keel
Salt River Project
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WECC Transmission Data Collection
• SRP Overview
• What is WECC?
• TRD Development
• Reasons for TRD
• Physical Parameters
– PCUR, Table W – 1
• NERC Standard versus WECC Criteria
– Common Corridor versus Common Tower
– Results
– Common Mode and Dependent Outage Data
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SRP Service Territory
Brian K. Keel – April 2012
• 2,900 sq Miles
• Portions of Maricopa, Gila, and Pinal Counties
• Maricopa County = 9,203 sq. mi.
• State of Mass = 8,000 Sq. mi.
• State of Delaware =
• 1,953 sq. mi.
YUMA
LA PAZ
MOHAVE
COCONINO NAVAJO APACHE
GILA YAVAPAI
MARICOPA
PINAL
PIMA
GRAHAM
SANTA CRUZ
COCHISE
GR
EE
NLE
E
SRP Service Territory
Brian K. Keel – April 2012
Phoenix
Peoria
Glendale
Scottsdale
Mesa
Tempe
Gilbert
Chandler
Tolleson
Litchfield Park
Surprise
Goodyear
Avondale
Apache Junction
Queen Creek
Fountain Hills
Paradise Valley
Eastern Mining Area
Brian K. Keel – July 2012
WECC TRD
• Developed first, 1st year data in 2006!
• WECC Subcommittee of Planning Coordinating Committee, Reliability Subcommittee called RPEWG = Reliability Performance Evaluation Work Group
• TRD Design development
– Spreadsheet based data submittal
– Design Based
Brian K. Keel – April 2012
Reasons for TRD Development
• Data to use for PCURs
• Common definition of terms & data format for WECC
• Basis for probabilistic planning methods (re-evaluated with NERC Compliance)
• Parameter trending and reaction
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TRD – Physical Parameters
• Design parameters - Circuits
– Conductors per phase, # of OHGW, Insulation type, Structure Materials, Structure types, Circuits per structure, Terrain, Elevation
• Design Parameters – Transformers
– Single or 3 Phase. Rating, Age
• A concentrated effort to find Common Tower versus Common Right of way Performance
Brian K. Keel – April 2012
WECC Criteria
Brian K. Keel – April 2012
• Applicability
• 4.1. Functional Entities
• 4.1.1 Planning Coordinator
• 4.1.2 Transmission Planner
• 4.2. Facilities
• 4.2.1 Part 1.1 applies to only Adjacent Transmission Circuits where both circuits are greater than or equal to 300 kV.
• 4.2.2 Requirement R1 only applies to effects on facilities external to a
• Transmission Planner area.
• 4.2.3 Part 1.1 of Requirement R1 does not apply to Adjacent Transmission Circuits that share a common right-of-way for a total of three miles or less, including – but not limited to – substation entrances, pinch points, and river crossings.
• 5. Effective Date: April 1, 2012
WECC Criteria
• 1.1. 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 0.033 outages per year).
Brian K. Keel – April 2012
Current Definition
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Circuit A Circuit B
Common
Tower
>= 100 kV
Circuit B Circuit C
Adjacent
Circuit
>= 300 kV
Circuit A Circuit C None
Brian K. Keel – April 2012
WECC Criteria
Brian K. Keel – April 2012
WECC PCUR
• WECC Criterion to NERC Standard for corridor transmission lines
• Defined process to show acceptable reliability of the corridor
• Based on:
• MTBF
• Robust Line Design
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WECC TRD
• Number of outages very similar • Number of miles of Common Right of Way 2 times
Common Tower – Common Right of Way half the outage rate
• COT = 8386 miles CRW = 15,530 miles
Brian K. Keel – April 2012
A SUMMARY OF OUTAGE EVENTS FOR WECC 230-500 KV LINES
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A SUMMARY OF OUTAGE EVENTS FOR WECC 230-500 KV LINES
Events 2010 2009 2008
Independent 1365 1297 1462
Common-mode 77 70 85
Dependent 94 55 59
Total Number of Events 1536 1422 1606
Major Causes of Common-mode Outages
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Major Causes of Dependent Mode Outages
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Conclusions
• Numerous efforts to examine Transmission outage data, NERC, WECC, ECAR, CEA
– Efforts needed to insure data accuracy
– Need to insure extract value, before asking for more
– TRD has value independent of TADS
– Right of Way data
– Physical parameter uses….
Brian K. Keel – April 2012