A review of signal energy analysis for the rapid determination of dynamic security limits

This article presents an overview of the signal energy method for the rapid determination of power system dynamic security limits. The key questions concerning this method are addressed. These include: (1) What is the basis of signal energy transient-stability-limit estimation? (2) Which physical quantity(ies) yield(s) the most accurate estimates? (3) How is the method used for accelerating the transient-stability-limit search? and (4) Can it be adapted to multiple-processor environments (i.e., either multiprocessor work stations or local area networks (LANs))? Signal energy limit search strategies, deployed on single-processor hardware, are shown to be extremely rapid and accurate, and to compare favourably to the published performance of the only other known method for accelerating the transient-stability-limit search (i.e., the “second kick” method). Also, tests show that by combining signal energy analysis and multiple processors, transient-stability-transfer-limit determination is achievable, on average, in less than the time required for two simulations and with an error under 1%.