关键词: 多相电机, 开路故障, 故障诊断, 混合逻辑动态模型

Abstract: Aiming at the open-circuit fault of power devices in a five-phase permanent magnet synchronous motor drive system, an open circuit fault diagnosis method based on the residual current of mixed logic dynamic model was proposed to improve the reliability and safety performance of the system furthermore. Based on the analysis of continuous current state variables and discrete switching signals in the motor drive system, a mixed logic dynamic model of the motor drive system was established to estimate the real-time current state of the motor. The residual between the model and the actual current was chosen as the diagnostic feature. The relationship table was designed by analyzing the residual current polarity under
different fault states to achieve specific open-circuit fault location. Experiments show that the method can effectively diagnose single and two power devices open-circuit faults in the same bridge of a five-phase permanent magnet synchronous motor drive system, and the diagnosis time is less than 50% of the basic current cycle.

Key words: multi-phase motor, open-circuit fault, fault diagnosis, mixed logic dynamic model