基于全矢EMD的低速重载轴承复合故障诊断方法

摘要

Aiming at low frequency of fault signal of bearings under low speed and heavy load and incomplete compound fault signal under single channel,being difficult to extract fault features,the full vector spectrum technique and empiri-cal mode decomposition(EMD)method are combined to solve fault diagnosis problem of the bearings under low speed and heavy load.Firstly,the time domain non-stationary signal is transformed into pseudo-stationary signal of angular domain through resampling in angular domain.Then the signal is decomposed and reconstructed by EMD.The dual-channel full vector spectrum technique is used to fuse homologous information and make up measurement incomplete-ness of signal under single channel.Finally,the fault is identified by spectral analysis of reconstructed signal to extract feature parameters,and the method is verified by experimental analysis.%针对低速重载轴承故障信号频率低、单通道情况下复合故障信号不完整,从而导致故障特征提取困难的问题,提出将全矢谱技术与EMD相结合的方法解决低速重载轴承故障诊断问题.首先对时域非平稳信号进行角域重采样转化为角域伪平稳化信号;然后通过EMD进行信号的分解与重构,采用双通道全矢谱技术进行同源信息融合,弥补单通道信号测量的不完整性;最后对重构信号进行频谱分析提取特征参量进行故障识别,并通过试验分析进行了验证.