Transient recovery voltages requirements for system source fault interrupting by small generator circuit breakers

There has been an increasing development of small generators of electric power. These generators of relatively low power, equal or less than 100 MVA, are protected in an economic way by generator circuit breakers which are located between the generator and the step-up transformer. In 1997 the IEEE Switchgear Committee issued a new edition of its standard C37-013 for generator circuit breakers, which covers mainly the applications with power transformers rated 100 MVA and above. A revision of this standard is currently prepared by the IEEE Switchgear Committee in order to broaden its scope to all generator circuit breakers. The purpose of this paper is to contribute to the definition of TRV requirements for system-source faults in the case of small generator circuit breakers connected to the step-up transformer by cables.

I. Introduction

During recent years increasing developments of small generations of electric power have taken place due to the increased use of gas turbines for backup power and deregulation which lead to the introduction of independent power producers.