An accurate method of neglecting dynamic saliency of synchronous machines in power electronic based systems

Abstract

In this paper, motivations for neglecting dynamic saliency in detailed models of power electronic-based systems are presented. A new method of neglecting dynamic saliency is introduced in which approximate operational impedances are derived from original dynamic salient models. New machine parameters are obtained by fitting to the approximate impedance curves, yielding model parameters in which dynamic saliency is eliminated. An example synchronous machine/converter system is provided that demonstrates the accuracy and increased simulation efficiency resulting from this technique. Therein, errors resulting from neglecting dynamic saliency are reduced from greater than 25% using traditional approximations to less than 0.6%. In addition, simulations using the new approximate model are greater than 48% faster than simulations based upon the original dynamic salient model.