局域均值分解和1.5维谱在机械故障诊断中的应用

摘要

Aiming at nonlinear, non-stationary characteristics of a mechanical failure vibration signal,a mechanical fault diagnosis method combining LMD and 1. 5 dimensional spectrum was proposed. In this approach,LMD method was applied to decompose the original signals into a finite number of product functions(PFs) , then the PFs containing fault information were analyzed with 1. 5 dimension spectrum to extract the characteristics. This method was endowed with characteristics of suppressing Gaussian white noise, detecting the nonlinear coupling feature. The method was verified by simulation signals and engineering examples of mechanical fault diagnosis effectively.%针对机械故障振动信号的非线性、非平稳特征,提出了局域均值分解和1.5维谱相结合的机械故障诊断方法.该方法首先对信号进行局域均值分解,将其分解为若干个PF分量之和,然后运用1.5维谱方法对含有故障特征信息的PF分量进行特征提取.该方法具有抑制高斯白噪声、检测非线性耦合特征等特性.仿真信号与机械故障诊断工程实例的分析验证了该方法的有效性.