A FAST APPROACH TO TRANSIENT STABILITY ESTIMATION USING AN IMPROVED POTENTIAL-ENERGY BOUNDARY SURFACE METHOD

In this paper, a new fast algorithm to perform online transient stabil ity assessment (TSA) in a power system is proposed. The TSA is concern ed with finding the critical clearing time (CCT), the stability limit, for a specified fault. The method possesses the merits of the fast sp eed of the potential energy boundary surface method and the accuracy o f the conventional time domain simulation technique. To expedite the a lgorithm, an efficient stopping criterion for postfault trajectory sim ulation is developed. Examples are given to show the problems of integ ration stopping criteria published in recent papers and how they are t ackled. Extensive test results on several systems, including the 10-ge nerator New England system, the 17-generator Iowa system and the IEEE 50-generator system, are reported.