Dynamics of voltage stability in a multi node system

Voltage stability is indeed a dynamic problem. In this paper, dynamics of voltage stability as effected by loads and exciter systems of generators are investigated. For the purpose of analysis, time domain simulation is applied to study voltage stability following a disturbance. The results of dynamic simulation for two cases of a multi node power system are shown. These cases are presented to illustrate some important mechanisms associated with voltage stability. The study shows that the nonlinearity of the load model is an important factor when determining the dynamics of voltage stability. It has been shown that a significant factor influencing the analysis of voltage stability is the modelling of generator field dynamics represented by the different IEEE standard models and parameters of exciters.

1 INTRODUCTION

The power system networks are the largest man-made interconnected systems in the world. In one power system network, all the rotating generators rotate synchronously producing alternating current at the same frequency, that is, all the generators operate together in dynamic equilibrium.