Hard-limit induced chaos in a fundamental power system model

The paper investigates complex nonlinear phenomena in a fundamental power system model represented in a single-machine infinite-bus formulation. The generator electromagnetics, electromechanics and its excitation control are modelled together by fourth-order differential equations. It is shown that when excitation control gains are set high (as in common industry practice) and when the excitation hard-limits are taken into account, this representative power system model undergoes global bifurcations including period-doubling cascades which lean to sustained chaotic behaviour. Specifically sustained complex oscillations result from the interaction of hard-limits and the system transients over a large range of realistic parameter values. The emergence of strange attractors is demonstrated in the paper by detailed numerical simulations and preliminary,analysis. Copyright (C) 1996 Elsevier Science Ltd.