Verification of a Fast Making Switch Based on Triggered Vacuum Switch and Vacuum Circuit Breaker

During synthetic making test a high speed making device is necessary to connect the switching device under test immediately after pre-strike during closing operation under applied voltage. A new kind of fast making device is emphatically expounded in this research, which is composed of triggered vacuum switch (TVS) and a fast vacuum circuit breaker (FVCB) with permanent magnetic actuator. Parallel-connected TVS and FVCB make up the basic optic-controlled module. And basic modules arranging in series can be increase the hold-off (withstand) voltage. When the closing command is triggered, TVS acts in several microseconds and carries the high making current first FVCB acts as the parallel protecting device for TVS, its closing command is sent simultaneously with TVS. Once FVCB closed the making current will shift to this branch, the erosion in TVS can be remarkably decreased. In this paper, a theoretical analysis is made and typical result is simulated with the power system simulation software EMTDC/PSCAD. The simulation result is similar to the experiment one. From the experiment and theoretical result it is known that the new kind of fast making device is feasible for synthetic making test of high voltage circuit breakers