基于瞬时无功功率感应电机转子断条故障诊断研究

Fault diagnosis of broken bar in induction motor based on instantaneous reactive power

在基于定子电流信号进行异步电机故障诊断时,转子断条故障特征频率分量常常被电流的基频分量淹没。针对这种情况,本文提出一种新型的基于瞬时无功功率的转子断条故障诊断方法。该方法首先对定子电压和电流进行Hilbert变换,然后在此基础上构建瞬时无功功率。通过对无功功率进行频谱分析,选取特征频率2ksf作为转子断条的故障诊断判据。同时定义一个新的故障严重程度系数,对感应电机转子故障严重程度进行判别。实验结果表明该方法能有效进行转子断条故障诊断。与传统的Hilbert模量方法和瞬时功率方法相比,该方法因没有交叉项而频谱简单;只需采集单相电流,不需要进行坐标变换,简化了硬件和软件,节省计算时间。

In traditional method based on the stator current signal of induction motor fault diagnosis,rotor broken bar fault characteristic frequency component was flood by the current fundamental frequency component. In view of this situation,a novel method of broken bar fault diagnosis based on the instantaneous reactive power was proposed. The instantaneous reactive power was defined as the cross product of the voltage,current after Hilbert transform. The characteristic frequency of 2ksf was used as the rotor broken bar fault diagnosis criterion by reactive power spectrum analysis. At the same time,In order to know the induction motor rotor fault severity discrimination,a new fault severity factor was defined. The experimental results showed that this method can effectively diagnose the rotor broken bar fault. The advantages of the method was simple spectrum,and no cross terms; only one current signal was needed,and it doesn＇t used coordinate transformation,the smaller hardware and software spending compared with the method based on Hilbert or instantaneous power.