基于RVACD和WPE感应电机转子断条故障诊断

摘要

针对感应电机转子断条故障诊断存在故障信号复杂多变、诊断时受负载和电源波动影响较大等诸多不足之处,提出断电残压(Residual Voltage after AC dump,RVACD)和小波包熵(Wavelet Packet Entropy,WPE)的故障诊断方法.以电机断电后残余电压为研究对象,建立转子断条故障的断电残压模型；分析断电残压信号频谱,得到故障特征频率；结合小波包和信息熵理论得到小波包Shannon熵,计算并与正常电机熵值作对比,得到故障诊断依据.仿真结果表明,断电残余电压可有效避免外界因素的干扰,断电残压频谱简单明了,小波包熵值作为故障诊断依据简单可靠,为工程实际提供了新的思路.%Based on many deficiencies that exist in induction motor rotor bar broken faults diagnosis, such as the signals were difficult to extract, were easily influenced by the variation of the loads and the electrical source, a method based on residual voltage after AC dump and wavelet packet entropy was introduced. Analyzed the residual voltage after AC dump and build the modal of the rotor bar broken faults. Use the frequency spectrum analysis method and wavelet packet entropy to get the fault characteristic frequency and the wavelet Shannon entropy. Through comparing with normal motor's to diagnosis the faults. Simulation showed that the residual voltage after AC dump could avoid the influence of the outer factors. The wavelet Shannon entropy could be used to diagnose the rotor bar broken faults. This method was effective, and easy to be used in engineering.