1. Observations using cmpldw WECC MVWG Meeting June 2015 Eric Bakie

2. Agenda Observations using cmpldw in seasonal studies Review of fault event data as compared to simulation data using motorw and cmpldw load representation 2

3. Observations Idaho Power is observing significant load tripping in seasonal studies that include cmpldw representation –2015 Light Summer50 MW (3-PH Fault at MPSN) 13 MW (SLG Fault at MPSN) –2015 Heavy Summer286 MW (3-PH Faults at HMWY) 13 MW (SLG Faults at HMWY) –2015 Heavy Summer195 MW (3-PH Faults at OBPR) 146 MW (3-PH Faults at ONTO) 3 MW (SLG Faults at OBPR) cmpldw motor trip pickup level and time delay model parameters appear to be very sensitive and may be too conservative 3

4. Event #1 ABC Fault - Trip Hemingway-Summer Lake 500kV (Trip) Midpoint-Hemingway 500kV (Trip) Fault Location 110mi from Hemingway 500kV toward Burns 500kV on Hemingway - Summer Lake 500kV Line 4

5. 3-Phase Fault – Trip 110mi from Hemingway 500kV toward Burns 500kV (HMWY-SMLK 500kV) 5

6. Hemingway 500kV Bus Phase and Sequence Voltages 6

7. Event #1 Area Load and ID-NW Flow 7 Fault Location Pld shed cmpldw 110mi from Hemingway 500kV15.6 MW Event #1 PI data does not clearly indicate 15MW of load was tripped Fault is fairly remote from load

8. Voltage Recovery at HMWY 8

9. Event #2 Close – ABC Fault - Trip Ontario – Caldwell 230 kV (C-T) Fault Location 9.83mi from Ontario 230kV toward Caldwell 230 on Ontario – Caldwell 230kV Line 9

10. Close-into 3-PH Fault-Trip 9.83 mi from Ontario 230kV (ONTO-CDWL 230kV Line) 10

11. Area Load Change (Event #2) 11 Fault Location Pld shed cmpldw 9.8 mi from Ontario 230kV on Ontario – Caldwell 230kV Line 25.0 MW Event #2 PI data does not clearly indicate load was tripped Fault is close to load

12. Voltage Recovery at ONTO 230kV Bus cmpldw with tripping enabled 12

13. 13 Voltage Recovery at ONTO 230kV Bus cmpldw with tripping blocked

14. Conclusions 14 Event #1 is too remote from load to make an accurate determination if load loss occurred Event #2 does not provide clear indication that load was tripped during fault cmpldw motor trip pickup level and time delay are likely too sensitive blocking tripping of cmpldw using 15hs4 records provided best match

15. Questions Eric Bakie, P.E. SYSTEM PLANNING ENGINEER Idaho Power | System Planning (208) 388-5677 ebakie@idahopower.com 15