基于瞬时频率的旋转机械故障诊断

Rotating Machinery Fault Diagnosis Based on Instantaneous Frequency

基于瞬时频率的物理意义,通过单分量和多分量信号瞬时频率的仿真对比分析,提出一种应用EMD-HHT(Empirical Mode Decomposition & Hilbert-Huang Transformation,EMD-HHT)获取瞬时频率的方法。将EMD-HHT用于实测的旋转机械振动信号处理,利用获取的瞬时频率和Hilbert边缘谱作为故障特征对旋转机械进行故障诊断。试验结果表明,瞬时频率特征较好地描述了相应故障类型,在旋转机械故障诊断领域具有很好的应用前景。

Instantaneous frequency was presented to describe the dependency of frequency components on time for non-stationary signals, which is a powerful alternative to the Fourier-based spectral analysis that provides insufficient resolution for the temporal progression of all frequency components. Based on the newly developed instantaneous frequency scheme and physical meaning definition, instantaneous frequency characteristics of mono-component and multi-component signals were simulated and analyzed, an effective decomposition scheme named Empirical Mode Decomposition＆ Hilbert-Huang Transformation was developed. Experimental vibration signals from a bearing test rig about different faulty location were analyzed with EMD-HHT. The result shows that instantaneous frequency can be used for system failure prediction, which encounters promising application in the rotating machinery fault diagnosis field.