Research on Fault Tolerance of DSEM Starting/Generating System

The faults of power devices and windings in the starting/generating system of doubly salient electro-magnetic machines pose a great threat to the reliability of the system. This paper presents fault tolerant methods for three-phase DSEM starting/generating system based on a bridge converter with bidirectional switching. The paper analyzes the starting /generation operating characteristics of doubly salient electro-magnetic machines and the system fault types firstly. On this basis, in order to improve the torque output capability of the starting operation after fault and the power output capability of the generation operation, fault-tolerant conduction loops of the starting/ generating system under various open circuit faults are analyzed. Finally, a Simulink simulation model is built, and the results verify that the proposed control strategy can increase the torque output and restrain the output power drop in the starting stage and power generation stage respectively.