基于波形特征的地铁牵引整流器二极管开路故障诊断方法

Fault diagnosis method of diode open circuit in metro traction rectifier based on waveform characteristics

针对地铁牵引整流器内部二极管故障率高且诊断困难的问题,提出基于输入电流和输出电压的波形特征进行二极管开路故障诊断的方法。基于地铁牵引整流器的电路拓扑结构,分析了发生二极管开路故障前后整流器输出电压与输入电流波形的变化规律;在此基础上首先利用输出电压的波形特征检测整流器的二极管开路故障并确定疑似故障时间,然后仅利用各整流桥的一相输入电流确定故障二极管所在的整流桥并识别具体的故障位置。基于MATLAB/Simulink平台的仿真验证结果表明,所提地铁牵引整流器故障诊断方法不受故障位置、故障时间、系统运行负载等因素的影响,具有良好的可靠性与适应性。

Aiming at the problems of high failure rate of diodes and difficult diagnosis in metro traction rectifier,an open circuit fault diagnosis method based on the waveform characteristics of input current and output voltage is proposed. The variation law of output voltage and input current waveforms of rectifier before and after diode open circuit fault is analyzed based on the circuit topology of metro traction rectifier. On this basis,the rectifier diode open circuit fault is detected and the suspected fault time is determined by using the output voltage waveform features,and then the rectifier bridge in which the fault diode is located is determined and the specific fault position is identified only by using one phase input current of each rectifier bridge. The simulative results based on MATLAB/Simulink platform show that the fault diagnosis method of metro traction rectifier is not affected by fault location,fault time,system running load,and has good reliability and adaptability.