Abstract
The notion of umbrella contingencies is rigorously defined in the context of the security-constrained optimal power flow (SCOPF) problem in both its deterministic and probabilistic forms. The set of umbrella contingencies is a subset of the set of credible contingencies that is sufficient to attain levels of security and economic performance identical or nearly identical to those found when all credible contingencies are considered. This paper shows how to identify the members of the umbrella contingency set from the norms of the Lagrange multiplier vectors associated with the post-contingency power balance relations of the SCOPF. A case study of the deterministic SCOPF investigates the range of validity of the set of umbrella contingencies as the system demand varies. In addition, we analyze the validity of the umbrella contingency set when lowly ranked contingencies are left out in a stochastic SCOPF problem.
| Original language | English |
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| Title of host publication | 15th Power Systems Computation Conference |
| Publication status | Published - 1 Aug 2005 |
Keywords
- Umbrella contingency, security-constrained optimal power flow, Lagrange multipliers, contingency ranking