基于广义解调时频分析的包络阶次谱在齿轮故障诊断中的应用

Application of the envelope order spectrum based on the generalized demodulation time-frequency analysis to the gear fault diagnosis

提出了基于广义解调时频分析的包络阶次谱方法,并将它应用于齿轮瞬态信号的分析。广义解调时频分析是一种新的时频分析方法,它可以将多分量的信号分解为若干个具有物理意义的单分量信号的瞬时频率,每个单分量信号可以是调幅-调频信号,因此非常适合处理多分量的调幅-调频信号。而当齿轮发生故障时,其启停过程中的振动信号恰巧表现为多分量的调幅-调频特征。在基于广义解调时频分析的包络阶次谱方法中,首先采用广义解调时频分析方法将多分量的齿轮振动信号分解为若干个单分量信号,其次对各个单分量信号进行包络分析,然后对包络信号进行角域重采样,最后对重采样后的信号进行频谱分析,得到包络阶次谱,从而判断齿轮的工作状态。采用该方法分别对仿真和实验信号进行了分析,结果表明了该方法的有效性。

The envelope order spectrum based on the generalized demodulation time-frequency analysis is proposed and applied to the processing of the gear instantaneous signal in this paper. The generalized demodulation time-frequency analysis approach that is a new signal processing method can decompose a multi-component signal into some single-component signals whose instantaneous frequencies posse physics sense. While each single-component signal can be amplitud and frequency modulated signal, the generalized demodulation time-frequency analysis approach is very applicable for processing the multi-componennt amplitud and frequency modulated signals. When fault occors in gear, the gear vibration singal in the start-stop pro- cess shows the multi-componennt amplitud and frequency modulated characteristcs. In the method of envelope order spectrum based on the generalized demodulation time-frequency analysis, firstly the multi-component signal is decomposed into some single-component signals by using the generalized demodulation time-frequency analysis method; secondly the envelope analysis is applied to each single-component signal ; thirdly each envelope signal is resampled in angle-domain ; finally the spectrum analysis is applied to each resampled signal and the envelope order spectrum can be obtained. Furthermore, the gear work state can be identified according to the envelope order spectrum. The analysis results from the simulated and experimental signals show the effectiveness of the proposed method.