Research on Open Circuit Fault Location and Fault Tolerant Control of Inverter Power Transistor

Abstract

As the key equipment of power conversion, the stability of the inverter directly affects the working state of the equipment. Aiming at the open circuit fault of the power tube, this paper designs a fault diagnosis and fault tolerance scheme of a three-phase bridge inverter based on the current signal. Firstly, the amplitude and phase characteristics of the current vector are used to judge the fault and fault location of the power tube. Then the output fault characteristic signal is converted into a fault-tolerant control signal. The fault leg is switched into a fault-tolerant leg under fault-tolerant control of the inverter bridge. The simulation results show that the diagnosis method proposed in this paper can judge the health and fault status of the inverter with high accuracy and achieve fault tolerant control, improving the stability of the inverter.