Experimental study on power frequency short-circuit failure of MOV

Metal Oxide Varistors (MOV) has the characteristic of nonlinear resistance. It is the core component of surge protection devices (SPD). In order to avoid damage to the power distribution system which caused by the power frequency short-circuit failure of MOV, research is needed on short circuit failure of MOV. This research mainly used the experimental study method on the MOV whose maximum continuous operating voltage (Uc) and varistor voltage are different. By changing amplitude and short circuit current, voltage and short current which flow the MOV had been measured, and the short-circuit failure can be judged. Through the test, MOV breakdown time and the short-circuit current can be obtained while the Uc and varistor voltage are different. The results can provide reference for the rational allocation MOV in the design of surge protection device.