wecc experience in the collection of transmission common mode and dependant...
TRANSCRIPT
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
2
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