Ordinal optimization based security dispatching in deregulated power systems

Due to the uncertainty in the forecasting of load patterns, security dispatching finds the generation pattern, which is the most economic and passes all N - 1 contingency tests with respect to (w.r.t.) all possible load patterns. The Monte Carlo simulation based method is computationally infeasible for practical scale power systems. In practice, usually only the most possible load pattern is considered in the security dispatching. In this study, we first show that this leads to the highly optimized tolerant property of power systems, and sometimes cascading failure. Then we develop an ordinal optimization based method to address this issue. This new method finds an economic generation pattern with quantifiable secure probability w.r.t. all possible load patterns. This method is demonstrated on a modified IEEE 30-bus standard power system. We hope this study sheds some insight on the understanding of power system collapse, especially the cascading failure.