基于数学形态谱的逆变器功率管开路故障诊断

针对逆变器功率管开路故障,提出一种基于数学形态谱的逆变器开路故障诊断方法。利用逆变器故障状态下的三相输出电流出现波形上缺失、下缺失、上下都缺失以及严重畸变的差异,求取正常电流信号及上述4种故障电流信号的形态谱,提取形态谱中前11个归一化谱值作为特征向量输入ELM神经网络进行区分,并结合简单的三相输出电流故障判别机制,实现故障功率管的准确定位。仿真结果表明,该方法的故障区分率超过96%。最后利用实验数据验证了所提方法的有效性。

Open-circuit Fault Diagnosis of Inverter Transistor Based on Mathematical Pattern Spectrum

In consideration of the open-circuit fault in an inverter transistor, a diagnosis method for the inverter''s open circuit fault is proposed based on mathematical pattern spectrum. When the inverter is in a fault state, the differences in the three-phase output current waveform, such as positive half-wave missing, negative half-wave missing, positive and negative half-waves missing, and serious distortion, are utilized to obtain the pattern spectrums of normal current signal and the current signals under the above four types of fault, of which the first 11 normalized spectra are extracted as feature vectors and further input to the ELM neural network to perform classification. With the combination of simple three-phase fault diagnosis criterion, the fault transistors can be positioned precisely. Simulation results show that by using the proposed method, the fault diagnosis rate is higher than 96%. In the end, the experiment data were used to verify the effectiveness of the proposed method.