Distribution Property of Transient Recovery Voltage of Vacuum Switch with Multi-break during Short-circuit Current Interruption

Voltage distribution relation of vacuum switch (VS) with multi-break determined its breaking capacity in certain degree. The distribution properties of transient recovery voltage (TRV) and dielectric recovery characteristics of vacuum switch are studied by experiment in this paper. The experimental prototype is set up. The voltage distribution of the interrupters with grading capacitors and without grading capacitors is compared. When three interrupters parallel connect different grading capacitors, short-circuit current is interrupted under the conditions of three interrupters contacts synchronous or asynchronous parting. The experimental results show that successful interruption mostly due to the good voltage sharing in the dielectric recovery process. The voltage distribution is mainly decided by interrupters' arc resistances in the dielectric recovery process, whereas it is decided by their equivalent capacitance after the dielectric recovery process. Therefore, high controllability actuator and proper grading capacitors are important factors for multi-break vacuum switch to interrupt successfully.