基于第二代小波变换的转子碰摩故障特征提取方法研究

Study of the Fault Feature Extraction Method for Rotor Rub-impact Based on the Second Generation Wavelet Transformation

为了能够提取隐含在振动信号中的故障特征,利用第二代小波对称、紧支撑和冲击振荡衰减的特点,有效地提取具有冲击响应特性的故障特征。实验证明,即使采用较小支撑区间的此类小波,也可获得理想的效果。另外,为了获得与原始信号相同的时间分辨率,采用单支重构的方法分别对逼近信号和细节信号处理,得到了转子碰摩故障的时域响应特征,为故障诊断和预示提供了一种分离故障时域特征的方法。

To extract fault features that were submerged in vibration signals, the paper sufficiently extracted fault features with impact response properties by utilizing the characteristics of the second generation wavelets such as symmetrical, compactly supported and decaying impact oscillation. Experimental results show that ideal effects are achieved even if such wavelet with less supported intervals are used. Moreover, for the purpose of getting the time resolution that is the same as its original signal, a single-branch reconstruction method is used to process approximation signals and detail signals respectively, which produces the time domain response features of rotor rub-impact faults. The method provides a new approach to the separation of time domain features from vibration signals during fault diagnosis and prognosis.