基于线调频小波路径追踪阶比循环平稳解调的齿轮故障诊断

为从变转速齿轮箱振动信号中提取齿轮故障特征,提出基于线调频小波路径追踪的阶比循环平稳解调方法。该方法利用线调频小波路径追踪算法估计振动信号中的转速信号,根据转速信号对信号进行等角度采样,获取角域周期平稳信号,求取角域信号的循环自相关函数,在特征循环阶比处对循环自相关函数进行切片,并对切片进行解调分析得到切片解调谱,依据切片解调谱进行齿轮故障诊断。由于线调频小波路径追踪算法具有精度高和抗噪能力强的优点,而循环平稳解调算法可以有效提取淹没在噪声中的周期性故障特征,因而,该方法结合了二者的优点,适合于变转速齿轮信号的故障特征提取。算法仿真和应用实例表明,该方法能有效地提取变转速齿轮箱振动信号中的齿轮故障特征。

Gear Tooth Fault Diagnosis by Using Order Cyclostationary Demodulating Approach Based on Chirplet Path Pursuit

In order to extract the fault characteristic from vibration signal of a gearbox with variable rotate speed,the order cyclostationary demodulating approach based on chirplet path pursuit is proposed.In this proposed approach,the rotate speed signal is estimated by the chirplet path pursuit.According to the rotate speed signal,the angular domain cyclostationary signal is obtained by even angle sampling to the original signal.The autocorrelation function of angular domain signal is calculated and the slice of autocorrelation function on the characteristic cycle order is computed.Do the demodulating on the slice to acquire the slice demodulation spectrum which is used to diagnosis the gear fault.Since the chirplet path pursuit has the advantage of high precision and good anti-noise ability,moreover,the cyclostationary demodulating approach can extract the cycle fault feature from noise signal.So,the proposed approach inherit the merit of both,and is suitable for extracting fault feature from gear signal with variable rotate speed.Simulation and application examples show that the proposed approach is an effective way to extract the gear fault characteristic from vibration signal of gearbox with variable rotate speed.