基于EMD和HT的旋转机械振动信号时频分析

Time-Frequency Analysis of Vibration Signals in Rotating Machinery

把一列时间序列数据通过经验模态分解 (Em pirical Mode Decomposition,简称 EMD)成本征模函数组(Intrinsic Mode Function,简称 IMF) ,然后经希尔伯特变换 (Hilbert Transform ation,简称 HT)获得频谱的信号时频分析新方法引入到旋转机械振动信号处理领域。介绍了该方法的理论和算法。首先 ,采用调频调幅仿真信号对该方法进行仿真验证 ;其次 ,把一实测的旋转机械油膜涡动故障振动信号进行了基于 EMD和 HT的时频分析。仿真和实测信号的分析结果说明 ,用基于 EMD和

The existing signal processing method based on empirical mode decomposition(EMD) and Hilbert transformation (HT) is that,first,separate series data to components with different time scale,say,intrinsic mode function(IMF) using empirical mode decomposition,then apply the Hilbert transformation to every IMFs.The result of the method is the spectrum of the HT.In the paper,the EMD and HT based time frequency analysis method is introduced to the field of vibration signal processing in rotating machinery.The method and algorithm are explained in detail and verified by analyzing a simulated vibration signal with frequency and amplitude modulation and a real oil film whirling vibration signal.Analyzed results show that the EMD and HT based time frequency analysis method is valid in the field of vibration signal processing in rotating machinery.