基于连续小波变换系数的柴油机异响故障特征提取与诊断

用Morlet小波对EQ6BT柴油机活塞敲缸响、活塞销响的缸体振动信号进行连续小波变换，然后将所得到的小波变换系数作出尺度—能量谱以及三维能量谱图，从而实现了对柴油机异响故障的特征提取和诊断。结果表明：利用Morlet连续小波变换系数的尺度—能量谱和三维能量谱图，能够直观而有效地检测和区分EQ6BT柴油机活塞敲缸响、活塞销响两种故障及其故障的严重程度。

Feature Extraction and Diagnosis from the Abnormal Sound Faults of Diesel Engine Based on the Continuous Wavelet Transform Coefficients

This paper studies the applications of Morlet continuous wavelet transform coefficients method on feature extraction and fault diagnosis of diesel engine's abnormal sound faults.Through the transform coefficients of the vibrant signals of EQ6BT diesel engine's piston knock and piston pin knock,a scale- power spectrum plot and a 3D power spectrum plot are obtained,and the characteristic of these two spec- trum plots can be used for classification.With this approach,feature extraction and fault diagnosis of diesel engine are made.The result shows that,by using the scale-power spectrum plot and the 3D power spectrum plot,the piston knock faults and piston pin knock faults can be deteeted and distinguished di- rectly and effectively.Moreover,the degrees of faults can also be detected.