1. Northeast Congestion Management/SPS in TCR Calculations James J. Teixeira John Moseley

5. Calculation Overview

6. Powerworld SimAuto/Access Code

7. With SPS

8. SPS Monitored Elements

9. SPS Protected Elements Downstream of SPS Monitored Elements, in direction of power flow, usually next limiting element after a Monitored Element. SPS Monitored Element Upstream must reach arming level under contingency prior to a Protected Element loading above Emergency Rating under contingency for it to be protected. Determined by repetitive power flows, increasing transfer level after an element was considered protected.

10. Path Protected Elements

11. Calculation Example – no SPS Transfer Level -72 MW NE to N Contingency

12. Ignore Because Monitored Element Transfer Level 2.5 MW NE to N Also Monitored Element

13. Ignoring all Monitored Elements Transfer Level 42 MW NE to N Monitored Elements are loaded above arming level prior to this line overloading so it is Protected

14. Another Protected Element Transfer Level 741 MW NE to N

15. As Transfer Increases Transfer Level 1090 MW NE to N

16. 95% of Arming Level Reached Loaded to 95% of Arming Level Contingent Lines in Service Transfer Level 1417 MW NE to N

17. Contingent Loadings Transfer Level 1417 MW NE to N Generation to be Tripped by SPS DC Tie