Hilbert解调制方法诊断异步电机轴承故障  

Diagnosis of Bearing Fault in Induction Motors Using Hilbert Demodulation Approach

作　　者：宋向金 王卓[1,2] 胡静涛 祝洪宇[3] Song Xiangjin;Wang Zhuo;Hu Jingtao;Zhu Hongyu(Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China;University of Chinese Academy of Sciences Beijing 100049 China;School of Electronic and Information Engineering University of Science and Technology Liaoning Anshan 114051 China)

机构地区：[1]中国科学院沈阳自动化研究所,沈阳110016 [2]中国科学院大学,北京100049 [3]辽宁科技大学电子与信息工程学院,鞍山114051

出　　处：《电工技术学报》2018年第21期4941-4948,共8页Transactions of China Electrotechnical Society

基　　金：国家重点研发计划项目(2016YFD0700100 2016YFD0700105);中国科学院重点部署项目(KFZD-SW-415)资助

摘　　要：针对电机电流信号特征分析(MCSA)方法诊断轴承外圈故障时易受到基频频谱泄露和偏心谐波以及供电系统噪声的影响,使得MCSA方法无法诊断低负载运行条件下的轴承外圈故障问题,提出一种基于Hilbert解调方法提取定子电流平方包络线的诊断方法。首先使用Hilbert变换构造定子电流解析信号,并提取定子电流解析信号的平方包络线;然后对提取的平方包络线做快速傅里叶变换(FFT)分析;最后根据FFT频谱中是否存在故障特征频率fof判断轴承是否发生故障。该方法能够将故障特征频率的检测从传统的边频带成分|f1±fof|转换为对轴承外圈故障特征频率fof的直接检测,能够有效消除基频频谱泄露和供电系统强噪声的干扰。电机在不同负载运行状态下的实验结果均验证了所提方法的有效性和稳定性。Because of the influence of the spectral leakage of the main frequency component,eccentricity harmonics and power supply noise,motor current signature analysis(MCSA)is unable to detect the bearing outer raceway fault when an induction motor(IM)operates under the light load conditions.In this paper,a bearing fault diagnosis method based on the squared envelope approach of the motor stator current using Hilbert demodulation technique was proposed.An analytical signal corresponding to the stator current signal was constructed first using Hilbert transform and then a squared envelope was obtained from the analytical signal.Second,the Fast Fourier Transform(FFT)of the squared envelope was investigated.Finally,the motor bearing failure was determined based on whether the characteristic fault frequency fof could be found in the squared envelope spectrum or not.The proposed method can be used to detect the characteristic fault frequency fof directly instead of detecting the sideband components around the supply frequency|f1±fof|as used in traditional MCSA.Thus,the proposed approach can significantly reduce the negative influence of the spectral leakage of the main frequency component spectral and the power supply noise.The experimental results under different load conditions clearly prove the effectiveness and stability of the proposed method.

关 键 词：异步电机 轴承故障 HILBERT 变换 定子电流 

分 类 号：TM343[电气工程—电机]