SLIDE 1
Decreasing Fault Current
August 13, 2019
- Goal
- Data Used
- Limitations
- Results
- Findings
- Recommendations and Next Steps
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Tyson Niemann Associate Engineer II Overview Goal Data Used - - PowerPoint PPT Presentation
Tyson Niemann Associate Engineer II Overview Goal Data Used - - PowerPoint PPT Presentation
Decreasing Fault Current August 13, 2019 Tyson Niemann Associate Engineer II Overview Goal Data Used Limitations Results Findings Recommendations and Next Steps 2 Goal Evaluate the potential fault current in the
SLIDE 2
SLIDE 3
- Evaluate the potential fault current in the
future based on data received for base case development
- To identify potential locations that have
dramatically changing in the future
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Goal
SLIDE 4
- 2019 Heavy Summer 3
- 2024 Heavy Summer 2
- 2029 Heavy Summer 1
- Location information was extracted from the
Geomagnetic Disturbance data collected for TPL-007
- Simulations performed in PowerWorld
- 3 Phase balanced bus fault
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Data Used
SLIDE 5
- Used cases designed for Power Flow to do
Short Circuit study
- Positive Sequence data only
- No Mutual Coupling data
- Dynamic data needed for machine impedance
- Incomplete location information
- Monitored fault current changes of all buses
- Results grouped to simplify analysis
- Visualization was limited to location information
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Limitations
SLIDE 6
19HS3 -> 24HS3
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SLIDE 7
19HS3 -> 29HS1
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SLIDE 8
- 382 buses had over 1 million amps as their fault
current
- 1,118 buses had over 100k amps as their fault
current
- GIS coordinates for 9,285 buses out of 24,548 buses
- After filtering all three cases decreasing, <1 mil,
with GIS, it leaves 1,147 buses (2,460 if you exclude GIS)
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Results
SLIDE 9
- 21 buses had 25% difference between 19HS3 and 24HS3
- 35 buses had 10-24% difference between 19HS3 and 24HS3
- 140 buses had 25% difference between 19HS3 and 29HS3
- 90 buses had 10-24% difference between 19HS3 and 24HS3
- 117 buses had 25% difference between 24HS3 and 29HS3
- 46 buses had 10-24% difference between 24HS3 and 24HS3
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Results Continued
SLIDE 10
- X” and R” cannot both be 0
- Generally fault current is decreasing in
simulations
- California was less pronounced than expected
- Northwest showed largest changes
- Want to understand why
- Hypothesis that changes to fault current tied to
large generator retirements
- Any other ideas?
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Findings
SLIDE 11
- Recommending the System Data Work Group
renew efforts to populate X’’ and R’’ accurately
- Default X” will be set to 0.12 pu instead of 0/0 and
capped at 999
- Further investigation by Planning Coordinators
and Transmission Planners in areas with significant >25%
- Discussion about best practice for reviewing relay
settings when changes are made to system
- Same study using short-circuit cases?
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Recommendations/Next Steps
SLIDE 12
Contact:
Tyson Niemann tniemann@wecc.org 801-819-7687
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