奇异谱分解和最大相关峭度解卷积在轴承故障声学诊断中的应用
Application of singular spectrum decomposition and maximum correlation kurtosis deconvolution in acoustic diagnosis of bearing faults
-
摘要: 故障特征成分的有效分离是滚动轴承复合故障诊断的核心,在强噪声及各个故障之间相互干扰耦合的背景下,滚动轴承声学复合故障诊断极具挑战性。本文提出一种优化奇异谱分解(optimized singular spectrum decomposition,OSSD)和参数自适应最大相关峭度解卷积(maximum correlated kurtosis deconvolution,MCKD)的复合故障声学诊断方法。采用包络峭度作为指标辅助OSSD快速确定最佳分解层数,以克服人工经验确定分解层数的不确定性,将信号分解为多个奇异谱分量。将故障特征频率能量幅值比作为指标自适应选择包含主要故障特征信息的两个奇异谱分量。利用参数自适应MCKD对所选择的最佳分量进行滤波和信号特征增强,通过包络谱分析提取故障特征频率实现故障诊断。通过滚动轴承仿真信号和试验声学信号验证了所提方法的有效性,该研究为旋转机械复合故障诊断提供了一种手段。Abstract: The effective separation of fault feature components is the core of rolling bearing composite fault diagnosis. Under the background of strong noise and mutual interference and coupling between various faults, the acoustic composite fault diagnosis of rolling bearing is very challenging. In this paper, a composite fault acoustic diagnosis method based on optimized singular spectrum decomposition (SSD) and parameter adaptive maximum correlated kurtosis deconvolution (MCKD) is proposed. The envelope kurtosis is used as an indicator to assist SSD to quickly determine the optimal decomposition level, so as to overcome the uncertainty of the artificial empirical determination of the decomposition level and decompose the signal into multiple singular spectral components. Combining the ratio of fault characteristic frequency energy amplitude as an index, the two singular spectral components containing the main fault characteristic information are adaptively selected. The parameter adaptive MCKD is used to filter the selected optimal component and enhance the signal feature, and the fault feature frequency is extracted by envelope spectrum analysis to realize fault diagnosis. The effectiveness of the proposed method is verified by the simulation and experimental acoustic signals of rolling bearings. The research provides a new means for the composite fault diagnosis of rotating machinery.