分段供电直线电机开关直通故障的在线诊断方法

Online Fault Diagnosis Method of Segment-powered Linear Induction Motor Switch Straight Through

针对分段供电直线电机开关直通故障,提出了一种在线诊断方法。通过分析分段供电拓扑结构的特点,利用ABC三相电压电流的包络线计算特征阻抗,并通过线性回归的方法研究了正常与故障模式下的特征阻抗与供电频率之间的关系,通过统计分析的方法研究了回归方程误差的分布规律,得到了故障判据。根据驱动脉冲信号对回归方程方差进行分段观测,以实现故障的定位。最后通过实验对方法进行了验证,实验结果表明:根据ABC三相电压和电流的包络线计算得到的特征阻抗,与供电频率可近似于线性关系,发生直通故障时这种关系会发生明显改变,利用此规律可有效进行直通故障的诊断与定位。

We proposed an online fault diagnosis method for solving the fault of straight-through switch in the segment-powered linear induction motor. By analyzing the characteristics of the structure of the segmented-power supply system, the characteristic impedance was calculated by using the envelope of ABC three-phase voltage and current, and the relationship between the characteristic and the power supply frequency was studied by the method of linear regression. Meanwhile, the distribution law of the regression equation error was studied by the method of statistical analysis, and the fault criterion was obtained. According to the variance of the driving pulse signal to the regression equation, the fault location was realized. The method was verified by the experiments finally. The results show that the characteristic impedance calculated according to ABC three-phase voltage and current envelope can approximate to linear with the power supply frequency, and this relationship will cause obvious change when direct through faults arise. This rule can be used for diagnosis and orientation for direct through faults.