Protection for overvoltage of 40.5 kV vacuum circuit breaker switching off shunt reactors
Based on the results of field tests of 40.5 kV vacuum circuit breakers switching off shunt reactors, the effects of metal oxide surge arrester (MOA) protections of several connecting types as well as C-R suppressers are compared in detail. In this switching situation, gapless combined MOAs and three-gap combined MOAs are helpful to suppress the overvoltage. Meanwhile, C-R suppressers can provide the most effective protection, and it is better to install them nearby the reactors rather than breakers.