Time-varying demodulation analysis for rolling bearing fault diagnosis under variable speed conditions
Time-varying demodulation analysis for rolling bearing fault diagnosis under variable speed conditions
复制标题
变速条件下滚动轴承故障诊断的时变解调分析
DOI：
10.1016/j.jsv.2017.03.037
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发表时间：
2017-07-21
影响因子：
4.7
通讯作者：
Wang, Tianyang
中科院分区：
文献类型：
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作者：
Feng, Zhipeng;Chen, Xiaowang;Wang, Tianyang
滚动轴承经常在变速条件下工作，导致非平稳振动。如何有效地从非平稳振动信号中提取时变故障频率是滚动轴承故障诊断的关键问题。为了解决这个问题，一个质量的时频分析的优秀的时频可读性和鲁棒性的噪声是必要的。为此，利用频率和时间的浓度（conceFT）方法。基于这种时频分析方法，考虑到滚动轴承振动的调制特性，提出了联合时变振幅和频率解调谱来揭示时变故障特征频率。首先，利用谱峭度选取对滚动轴承故障敏感的最佳频带。然后，在所选择的最佳频带内计算敏感信号分量的幅度包络和瞬时频率。接着，将ConceFT方法应用于幅度包络和瞬时频率，以生成时变幅度和频率解调谱。最后，通过分析时变解调频谱所揭示的时变频率，可以对滚动轴承故障进行诊断。该方法不受复杂时变边带的影响，对噪声干扰具有较强的鲁棒性。通过数值模拟信号分析说明了这一点，并通过实验室实验滚动轴承振动信号分析进一步验证了这一点。成功地诊断出了内外座圈的局部缺陷。(C)2017爱思唯尔有限公司版权所有
Rolling bearings often work under variable speed conditions, resulting in nonstationary vibrations. How to effectively extract the time-varying fault frequency from nonstationary vibration signals is a key issue in rolling bearing fault diagnosis. To address this issue, a quality time-frequency analysis of excellent time-frequency readability and robust to noise is necessary. To this end, the concentration of frequency and time (ConceFT) method is exploited. Based on this time-frequency analysis method, and considering the modulation feature of rolling bearing vibrations, we propose joint time-varying amplitude and frequency demodulated spectra to reveal the time-varying fault characteristic frequency. Firstly, the optimal frequency band sensitive to rolling bearing fault is selected by spectral kurtosis. Then, both the amplitude envelope and instantaneous frequency of the sensitive signal component within the selected optimal frequency band are calculated. Next, the ConceFT method is applied to the amplitude envelope and instantaneous frequency to generate the time-varying amplitude and frequency demodulated spectra. Finally, rolling bearing fault can be diagnosed by analysis of the time-varying frequency revealed by the time-varying demodulated spectra. This method is free from complex time-varying side bands, and is robust to noise interference. It is illustrated by numerical simulated signal analysis, and is further validated via lab experimental rolling bearing vibration signal analyses. The localized defects on both inner and outer race are successfully diagnosed. (C) 2017 Elsevier Ltd. All rights reserved.