一种新的感应电动机转子断条故障检测方法

A new method of broken-rotor-bar fault detection of induction motors

该文提出一种基于Hilbert模量频谱分析的感应电动机转子断条故障诊断的新方法.该方法是将Hilbert变换和小波分析方法相结合,得到解析小波变换,以准确判定负荷波动发生时刻,消除了负荷波动对断条故障特征频率的影响.将Hilbert模量定义成原始信号与其共轭信号的平方和,利用Hilbert模量将原相电流中的基波成分转换成直流成分,将转子断条的故障特征分量——(1-2s)f1转变为频率为的电流分量,解决了相电流频谱分析方法中断条故障特征分量很容易被基波淹没而难以突出故障特征分量的问题.仿真分析表明,该方法能克服传统的电流频谱分析法的缺点,对感应电动机转子断条故障给出正确无误的诊断结果.

This paper proposes a new fault detection method based on spectrum analysis of Hilbert modulus,which combines Wavelet Transform and Hilbert transform to detect induction broken-rotor-bar faults.Hilbert transform is introduced into Wavelet analysis to obtain analytical results of wavelet transform of the signals.Based on analytical results of wavelet transform,this method calculates the location of fault signature and eliminates the effect of the oscillation.The Hilbert modulus is defined as the sum of the square of a signal and its conjugation.It is used to covert the fundamental component in original phase current to the direct current component and to convert the fault characteristics frequency of broken-rotor-bar——（1-2s）f1 to current component of 2sf1 frequency.This method overcomes the shortcomings that the fault signatures are often concealed by the fundamental frequencies.The results of simulation demonstrate that the proposed method can overcome the drawback of the traditional current spectrum analysis method,and provides an accurate fault diagnosis.