Analysis of overall stability of multi-machine power systems

Conventional methods of assessing the stability of multi-machine power systems neglect many factors, such as flux variation in the synchronous machines and the effect of regulators and governors. With the smaller stability margins characteristic of present-day system design, correct representation of these factors may be of considerable technical and economic importance. Accordingly, a general stability analysis for a multi-machine system is developed, and the solution of the resulting equations by both analogue and digital means is described. The results of a typical stability study on a representative system are presented and the relative effects of various assumptions evaluated.