永磁同步电机逆变器故障的小波诊断

Diagnosis of Wavelet on Permanent Magnet Synchronous Motor Inverter Fault

针对三相PWM逆变器输出的相电流信号,采用db3小波基进行3层小波分解,提取一个低频系数和三个高频系数,然后对各个系数求出其能量值,按照顺序排成一列成为特征向量。建立MATLAB仿真模型,并对逆变器主电路开关器件的开路故障进行仿真,我们可以很方便地从故障的向量看出逆变器发生故障的精确信息。

Using db3 wavelet to analyze the phase current signal from three-phase PWM inverter, extracting a low-frequency coefficients and three high-frequency coefficients, then calculate the energy value of each factor, forming a row by the order to be feature vector. Establishes MATLAB simulation model to simulate the open-circuit of the inverter＇s main circuit switching device, results from simulation show that we can easily find the accurate information of inverter fault from the fault vector.