基于多项式Chirplet变换和变分模态分解的变转速工况轴向柱塞泵故障诊断

针对变转速工况轴向柱塞泵故障诊断时故障特征提取困难的问题,提出了基于多项式Chirplet变换和变分模态分解的诊断方法。首先使用多项式Chirplet变换估计瞬时频率;然后基于估计的瞬时频率重采样,将时域非平稳信号转化为角域平稳信号;最后对角域信号进行变分模态分解。根据峭度对所得的本征模态函数分量进行重构并作包络阶次谱分析,判断轴向柱塞泵中轴承的故障类型。实验结果表明,该方法有效提取了变转速工况轴向柱塞泵轴承的故障特征。

Fault Diagnosis of Axial Piston Pump Based on Polynomial Chirplet Transform and Variational Mode Decomposition Under Variable Speed Conditions

Fault features of axial piston pump are difficult to be extracted under variable speed conditions, a fault diagnosis approach is proposed using polynomial Chirplet transform and variational mode decomposition. First, polynomial Chirplet transform is applied to estimate the instantaneous frequency. Then the original signal in time domain is resampling to a stationary one in angular domain based on the estimated instantaneous frequency. Finally, the angular domain signal is decomposed by variational mode decomposition into a series of intrinsic mode functions, envelope order spectrum is applied to detect the bearing fault characteristic order and failure mode. The result of the experiment indicates that the new fault detection algorithm is efficient for the bearing of axial piston pump under varying speed conditions.