Power system online security operational trend analysis and simulation results

A novel power system online security operational trend analysis method is proposed in this paper. Based on the online operational mode and ultra-short term forecast operational mode (15mins later), the worst contingency set is determined as the union of the worst contingency in online and ultra-short term forecast operational mode, and the power system security evaluation indices are given out online for different security subject, such as voltage stability, critical interface stability, and transient stability. Simulation results on IEEE 39-bus system show that the proposed method can determine the worst contingency set and security evaluation index online accurately, reduce the number of contingencies, and improve security analysis efficiency.