基于小波变换的开关磁阻电机系统功率变换器故障诊断

Fault Diagnosis of Power Converter for Switched Reluctance Motor System Based on Wavelet Transform

适用于开关磁阻电机(SRM)驱动系统的功率变换器是决定系统可靠性的关键环节,功率变换器的长时间故障运行会导致整个系统的崩溃,因此,功率变换器的故障诊断具有重要的作用。采用离散小波变换方法,提取故障相电流的平均值与标准差的比值作为诊断特征量,对功率变换器斩波管和位置管的4种故障类型进行分析和讨论,实现了故障类型的确定与故障器件的定位。最后通过仿真和试验验证了所提的故障诊断方法具有良好的可行性和有效性。

The power converter applied to switched reluctance motor(SRM)drive system was a key link to the system reliability.Abnormal operation with faults for a long time could cause the collapse of the whole system,which indicated that the fault diagnosis for power converter in SRM had a large significance.The discrete wavelet transform method was used to extract the ratio of phase current mean to standard deviation which could be taken as the diagnostic feature.Four types of faults of power converter were analyzed and discussed.Determination of fault types and fault devices was implemented.Finally,the feasibility and effectiveness of the proposed method were proved by simulation and experiment.