NPC인버터 시스템에서의 새로운 고장검출방법

In this paper, a simple method of fault tolerant is proposed for improvement of reliability when the NPC inverter has a failure in the switchig device. The fault of switchig device is detected by checking the change of a leg-voltage in NPC inverter. Also, it is performed that two phase control method is used for supplying the balancing three phase voltage to the load continuously. This method has some advantage of a fast detection ability and a simple realization for fault detection, compared with a conventional method. The proposed method has been verified by simulation.