基于电流分析的开关磁阻电机功率变换器故障检测方法

Fault detection method of power converter for switched reluctance motor based on analysis of current

以开关磁阻电机不对称半桥型功率变换器为研究对象,提出一种该类电机不对称半桥型功率变换器主功率元件开路与短路故障综合在线检测方法。通过对开路与短路故障机理分析,挖掘故障相电流的奇异特征,揭示主功率元件开路与短路故障下各相电流差值畸变规律,提取故障特征量,提出并建立故障特征量集合,选取各相电流两两间差值为集合中诊断判定元素,设定诊断判据,实现故障发生、故障类型与故障相的诊断。再综合分析故障相电流的退磁时间占比与功率元件通断状态识别出故障元件。仿真与实验结果表明,该方法在不同工况下均可快速准确诊断出故障详情,且无需附加任何额外传感器。

A comprehensive on-line fault detection method for open-circuit and short-circuit faults is presented for the asymmetrical half-bridge power converter feeding switched reluctance motor.The study is focused on analyzing failure mechanism to excavate the singular feature of fault phase current and the difference between each current.The fault feature was extracted and a fault feature collection was proposed and founded,which included differences between each current,and were considered as diagnostic judgment element.And the diagnosis criterion was set to realize the diagnosis for the occurrence,type and location of the fault.Then based on the demagnetization time and on-off states of power elements of the fault phase,the fault component can be distinguished.The accuracy and effectiveness of the proposed detection method are validated with different conditions by the simulation results and experimental tests.Moreover,any additional sensors is not required.