Revision of TRV requirements for the application of generator circuit-breakers

The requirements imposed on generator circuit-breakers greatly differ from the requirements imposedon other transmission and distribution circuit-breakers. Due to the location of installation between thegenerator and the associated step-up transformer, a generator circuit-breaker must meet high technicalrequirements with respect to rated normal currents, short-circuit currents, fault currents due to out-of-phase conditions and transient recovery voltages. The question whether the transient recovery voltagerequirements laid down in IEEE Std C37.013-1997 (R2008) and in IEC/IEEE 62271-37-013 are adequatefor the application of generator circuit-breakers in modern power stations is considered in the presentwork.In order to quantify the transient recovery voltage requirements for the application of generator circuit-breakers a comprehensive survey of different fault conditions occurring in several power stations hasbeen performed. The fault transients’ simulations have been performed by means of the ElectromagneticTransients Program (EMTP).