摘要
支持向量机(support vector machine,SVM)应用于轴承故障诊断前,首先要提取轴承的特征信号.在以往的特征信号提取中,往往是依据已有的知识模型进行特征筛选.随着近年来深度神经网络(deep neural network,DNN)的应用与推广,自动编码器(auto-encoder,AE)在特征提取方面的优势尤为突出.作为一种无监督的学习方式,AE能够基于数据驱动提取信号的特征值,使得特征提取不再依赖于先验知识,从而让整个故障诊断过程更具智能化.本文运用改进的AE、去噪自动编码器(denoising autoencoder,DAE),进行轴承信号特征提取,并用SVM进行故障诊断.最终与基于经验模态分解(empirical mode decomposition,EMD)能量熵的SVM对比,反映具有无监督学习方式的DAE-SVM在轴承故障诊断方面的优越性,诊断准确率接近100%.
The fault feature should be extracted before the SVM was applied to the bearing fault diagnosis. In the previous feature signal extraction,it was based on the existing knowledge model. With the application and promotion of DNN in recent years,AE had a special advantage in feature extraction. As an unsupervised learning method,AE could extract the features of the signal based on data driven,making the feature extraction no longer depends on prior knowledge,and the whole fault diagnosis processed more intelligent. In this paper,the improved AE、DAE,were used to extract the features of the bearing signals,and the fault diagnosis was carried out by SVM. Finally,by compared with the SVM based on EMD energy entropy feature extraction,the superiority of DAE-SVM with unsupervised learning method was reflected in bearing fault diagnosis,and its diagnostic accuracy was nearly 100%.
引文
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