基于线调频小波路径追踪算法与EEMD的齿轮箱复合故障诊断方法

针对变转速下的齿轮箱中复合故障的故障特征提取,提出一种基于线调频小波路径追踪算法与集合经验模式分解的齿轮箱复合故障诊断方法。该方法先用线调频小波路径追踪算法从原始振动信号中提取转频曲线,根据转频曲线对原始振动信号进行等角度重采样,将时域信号转化为角域信号,再对角域重采样信号进行集合经验模式分解,根据相关系数选取合适的内禀模态函数,最后对所选取的内禀模态函数分量进行Hilbert包络谱分析,根据包络谱进行齿轮箱复合故障诊断。通过算法仿真和应用实例对包含齿轮局部故障和轴承局部故障的变转速齿轮箱复合故障进行分析,结果表明,该方法在无转速计的情况下能有效地提取变转速齿轮箱复合故障的特征。

A compound faults diagnosis method for gearbox based on chirplet path pursuit and EEMD

Aiming at the problem of extracting fault characteristic from gearbox with compound faults under the condition of changing rotating speed, a compound fault diagnosis method for gearbox based on chirplet path pursuit and ensemble empirical mode decomposition (EEMD) is proposed. In the proposed method, the rotating speed is estimated from original vibration signal by chirplet path pursuit algorithm. In order to transform the time domain signal to the angular domain signal, the even angle resampling is carried out to the original signal according to the obtained rotating speed. The angular domain resampling signal is decomposed by EEMD, and the suitable intrinsic mode function (IMF) is selected according to the correlation coefficient. The selected IMF is analyzed by the Hilbert envelope spectrum and the compound fault diagnosis of gearbox is executed according to the envelope spectrum. The results, obtained by the analysis of algorithm simulation and application examples to the gearbox with compound faults consisted of gear local fault and bearing local fault under the condition of changing rotating speed, show that the proposed method can effectively extract fault characteristic from gearbox with compound faults.