Power System Risk Assessment and Control in a Multiobjective Framework

TitlePower System Risk Assessment and Control in a Multiobjective Framework
Publication TypeJournal Article
Year of Publication2009
AuthorsFei Xiao, James D McCalley
JournalIEEE Transactions on Power Systems
Pagination78 - 85
Date Published02/2009
KeywordsAA09-001, AARD, Automatic Switchable Network (ASN), CERTS, power system security, RTGRM, System Security Tools

Traditional online security assessment determines whether the system is secure or not, but how secure or insecure is not explicitly indicated. This paper develops probabilistic indices, risk, to assess real-time power system security level. Risk captures not only event likelihood, but also consequence. System security level associated with low voltage and overload can be optimally controlled, using the NSGA multiobjective optimization method. A security diagram is used to visualize operating conditions in a way that enables both risk-based and traditional deterministic views. An index for cascading overloads is used to evaluate the Pareto optimal solutions. This paper shows that the multiobjective approach results in less risky and less costly operating conditions, and it provides a practical algorithm for implementation. The IEEE 24-bus RTS-1996 system is analyzed to show that risk-based system security control results in lower risk, lower cost, and less exposure to cascading outages.

Short TitleIEEE Trans. Power Syst.