基于断电后残余电压的感应电机定子故障诊断

为了提高感应电机定子绕组故障诊断的准确性,提出了一种基于Hilbert-Huang变换(HHT)的故障诊断新方法.选取断电后零序电压的基波分量作为定子故障特征,可有效避免电源不平衡和负荷波动的影响,直接反映电机定子的不对称度.利用Hilbert-Huang变换中经验模态分解(EMD)方法对断电后的零序电压进行了分解,提取出基波分量,通过计算其均方根值可以诊断出电机定子绕组故障.在一台4 kW的感应电机上进行的实验证明了该方法的可行性和有效性.

Induction motor stator winding fault diagnosis based on zero sequence voltage after switch-off

To improve the accuracy of the stator winding fault diagnosis in induction motor,a new diagnostic method based on the Hilbert-Huang transform(HHT) was proposed.The fundamental component of zero sequence voltage after switch-off was selected as the stator fault feature,which could effectively avoid the influence of the supply unbalance and load fluctuation and directly reflect the asymmetry in the stator.Using the empirical mode decomposition(EMD) based on HHT,the zero sequence voltage after switch-off was decomposed and the fundamental component was extracted.Then,the root mean square of the fundamental component was obtained to diagnose the stator winding fault.Experimental results on a 4 kW induction motor demonstrated the feasibility and effectiveness of this method.