一种单样本风电机组传动链故障诊断方法

A Single-sample Fault Diagnosis Method of a Wind Turbine Transmission Chain

针对风电机组传动链上故障相似度高的问题,提出了一种基于经验模态分解和信号均衡处理的单样本风电机组轴承故障诊断方法。该方法通过对实际监测故障信号进行经验模态分解,得到不同模态的信号分量;计算各模态分量的能量值和峰值,选择能量大且峰值高的部分模态分量进行信号重构,得到新的故障信号;对新的故障信号进行小波包分解,并将小波包分解第三层分量进行信号重构。将重构信号的方差作为故障诊断的特征值,对特征值进行非线性均衡处理,解决了信号互相淹没的问题。引入区分度的概念,用来量化不同故障信号之间的区别。试验结果表明,所提故障诊断方法有效,处理前后风电机组传动链上的4种故障间的区分度明显增大,说明试验方法具有强鲁棒性。通过与改进的模糊聚类方法和基于改进AlxeNet网络深度学习的方法对比,本文所提方法表现更优。该方法仅用单样本实现风电机组传动链故障诊断,符合风电机组低故障率的特点,对实际工程中风电机组排故效率的提高有重要意义。

Aiming at the problem of high fault similarity in the transmission chain of wind turbines,this study proposes a single-sample wind turbine bearing fault diagnosis method based on empirical mode decompo⁃sition and signal equalization processing.In this method,the signal components of different modes are obtained by empirical mode decomposition of the actual monitoring fault signal.The energy value and peak value of each modal component are calculated,and some modal components with large energy and high peak value are select⁃ed for signal reconstruction to obtain a new fault signal.The new fault signal decomposed by wavelet packet,and the wavelet packet is decomposed into the third layer component for signal reconstruction.The variance of the re⁃constructed signal is used as the eigenvalue of the fault diagnosis.Non-linear equalization is performed on the eigenvalues,which solves the problem of signal mutual submergence.The concept of discrimination is intro⁃duced to quantify the difference between different fault signals.The experimental results show that the fault diag⁃nosis method proposed is effective,and the discrimination between the four faults on the transmission chain of the wind turbine before and after the treatment is significantly increased,which shows that the experimental method has a strong robustness.Compared with the improved fuzzy clustering method and the deep learning method based on the improved AlxeNet network,the method performs better.The fault diagnosis method only us⁃es a single sample to realize the fault diagnosis of the transmission chain of wind turbines,which is in line with the characteristic of the low failure rate of wind turbines,and is of great significance for improving the trouble⁃shooting efficiency of wind turbines in actual projects.