摘要：本文分析了外接不控全桥整流电路的四相电励磁双凸极发电机的三种单相短路故障运行情况：绕组短路，二极管上管或下管短路。对于正常运行和不同的故障运行情况，利用有限元分析软件Ansoft建模仿真和实验相结合的方法对发电机在空载情况下的磁链、相电压、短路电流、输出电压、电枢反应等进行了详细的分析。比较不同短路故障对发电机的影响：下管短路故障对输出电压品质影响最甚，使输出电压平均值急剧下降且纹波率大大增加；但上管短路故障产生的短路电流最大，对电机发热影响最严重。

关键词：四相电励磁双凸极发电机；短路；故障；有限元分析；电枢反应

Abstract: In this paper, the single-phase short-circuit faults of four-phase doubly salient electro-magnetic generator with uncontrolled full-bridge rectifier topology were presented and analysised. Single-phase short-circuit faults contain winding short-circuit, diode on top short-circuit and diode underneath short-circuit. As to normal and different fault operation conditions, the flux, short-circuit current, phase voltage, output voltage, armature reaction of DSEG under no-load were analyzed by FEA simulation and experiments. Comparing the negative influence of different faults on DSEG, diode underneath short-circuit fault worst impacted on the quality of the output voltage, so that the average output voltage declined sharply and the ripple rate significantly increased. However, the short-circuit current of diode on top short-circuit fault was maximum, that worst impacted on motor heating.

Key words: four-phase DSEG;  short circuit;  fault;  FEA;  armature reaction