【目的】为了提高对称六相永磁同步电机(PMSM)驱动系统的可靠性,本文构建了基于九开关变换器的动态模型,并提出一种创新的逆变器开路故障诊断方法。【方法】在考虑开关管脉宽调制死区效应前提下,定义电机绕组端对地电压与开关管通断的逻辑映射,建立相电压-开关信号的动态对应关系,进而推导出混杂系统的统一逻辑模型。基于电压混合逻辑运算,对比标准与故障状态下的电压差异,实现开路故障的精准定位。【结果】仿真结果表明,对称六相PMSM逆变器发生开路故障时,通过动态逻辑变换与电压差值分析,可精准定位故障开关管。【结论】本文所提诊断方法可有效识别单一开关管或同一桥臂双开关管同时开路的故障,具有较高的准确性和普适性。

[Objective] To improve the reliability of the symmetrical six-phase permanent magnet synchronous motor (PMSM) drive system, this paper constructs a dynamic model based on a nine-switch converter and proposes an innovative open-circuit fault diagnosis method for the inverter. [Methods] Considering the dead-time effect of pulse width modulation, the logical mapping between the motor winding terminal-to-ground voltage and the switch state was defined. The dynamic correspondence between the phase voltage and the switch signal was established, and a unified logical model of the hybrid system was derived. Based on voltage hybrid logic operations, the voltage differences between standard and fault states were compared, and open-circuit faults were accurately located. [Results] The simulation results demonstrated that when an open-circuit fault occurred in the symmetrical six-phase PMSM inverter, the faulty switch could be accurately located through dynamic logic transformation and voltage difference analysis. [Conclusion] The proposed diagnostic method can effectively identify faults in a single switch or simultaneous open-circuit faults in two switches of the same bridge arm, demonstrating high accuracy and universality.

国家自然科学基金(51377168)