基于EMD分解及Hilbert包络的电机轴承故障诊断

Motor Fault Diagnosis Based on EMD Decomposition and Hilbert Envelope

为了解决对振动信号直接做傅里叶变化得到的频谱图极大值较多,且分布不规律,很难看出故障频率值的问题,基于EMD分解及Hilbert包络对某电机轴承故障进行了详细诊断,内圈的故障理论计算特征频率值为162.21Hz,而诊断的结果显示最大故障频率值为164.1Hz,两者非常接近。可见根据Hilbert变换的特点和电机轴承的振动信号,Hilbert变换可以通过解调振动信号而有效确定特征缺陷频率。

In order to solve the problem that there are many maxima of frequency spectrum obtained by Fourier transform of vibration signal,and the distribution is irregular,so it is difficult to see the fault frequency value.In this paper,a motor bearing fault is diagnosed in detail based on EMD decomposition and Hilbert envelope.The theoretical calculation characteristic frequency value of inner ring fault is 162.21 hz,and the diagnosis result shows that the maximum fault frequency value is 164.1 hz,The two are very close.It can be seen that according to the characteristics of Hilbert transform and the vibration signal of motor bearing,Hilbert transform can effectively determine the characteristic defect frequency by demodulating the vibration signal.