A New Approach to Transient Stability Region of Synchronous Generator

Abstract

This paper describes a method of analytically determining the domain of transient stability in state space for a synchronous generator. The motion of a synchronous generator is represented in the state space; and the rate of change of the direction of the motion is expressed by a series expansion of the distance along the motion. The stability boundary is determined by the minimal point of the differential coefficient of a sufficiently high order, based on the facts that every state on the stability boundary approaches the saddle point with time, and also that the direction of the trajectory changes discontinuously at the saddle point. As a numerical example, the method is applied to a simple synchronous generator connected to an infinite-bus. The results show that the most important part of the stability boundary can be obtained very accurately with a reasonable amount of computation.