The influence of power system parameters on breaks of fault currents in the generator circuit breaker

Abstract

The purpose of this paper is to study the factors that influence on the delayed current zeros phenomena in the generator network. For this purpose the equivalent circuit of the generator network was developed. The fault transients simulations have been performed by means of the Matlab/Simulink software package. Consequently, the dependence characteristics of the delayed current zeros phenomenon on the external power system parameters (inductance, length of power lines, reactive power balance) were obtained. The amount of reactive power generated by power lines depends on its length. This power, in turn, is consumed by the generation network and external power system. The greater the reactance of the external power system, the greater of this reactive power the generator consumes, which, in turn, increases direct-axis armature reaction and direct component of the short-circuit currents. The long arcing time by the delayed current zeros phenomena will cause damage to the transformer, circuit breaker and can negatively affect the stability of the power system. These results are also demonstrated numerically.