Effects of medium voltage capacitor bank switching surges in an industrial distribution system

Three effects of medium-voltage capacitor bank switching surges in an industrial distribution system are described. The switching duties on the medium-voltage circuit breakers could be exceeded under back-to-back switching conditions of the capacitor banks. The switching surges at the primary distribution voltage level could be transmitted through the transformer windings, and the resulting overvoltages could shut down the secondary connected DC or variable frequency AC drive loads. The capacitors could be stressed due to frequent switching surge overvoltages. It is shown that the effects of capacitor bank switching surges can be minimized and the switching duties on the circuit breakers can be reduced by series reactors in the capacitor banks, switching resistors, surge capacitors, and surge arresters at the primary and secondary voltage levels of the distribution system