基于小波包和包络谱的齿轮箱异响分析

Analysis of Abnormal Sound in Gearbox Based on Wavelet Packet and Envelope Spectrum

针对齿轮箱异响信号呈非平稳时变特征并伴随有强烈的背景噪声,介绍了基于小波包分解、频带能量分析和包络谱相结合的齿轮箱异响分析方法。首先对采集到的齿轮箱声学信号进行小波包分解,对该信号进行小波包能量化分,然后对照正常和异响发动机信号的能量特征向量,对明显差异的小波包系数进行重构,最后对重构信号进行包络分析提取故障特征频率为16.5Hz,与实际的故障特征频率相近,表明该方法适用于齿轮箱的故障分析。

The abnormal sound signals of gearbox are non-stationary, time-varying and are accompanied by strong background noise. This paper introduced an analysis method of abnormal sound that combined the wavelet packet decomposition, the energy band analysis and envelope spectrum. The paper decomposed the acoustic signals from the gearbox with wavelet packet, quantified the signals by wavelet packet energy, compared the energy eigenvectors of normal sound with those of abnormal sound of the engine signals, and then reconstructed the significantly different wavelet packet coefficients. Finally, envelope analysis was applied to the reconstructed signals. The fault characteristic frequency, 16.5 Hz, which is similar to the actual fault frequency, was extracted. It is demonstrated this method was suitable for failure analysis.