基于时间-小波能量谱熵的滚动轴承故障诊断研究

摘要

Aiming at periodic impulses in vibration signals of bearings,a new method so called time-wavelet energy spectrum entropy was proposed for rolling element bearing fault diagnosis.Firstly,an impulse response wavelet was constructed to obtain wavelet energy spectrum in time domain by using the continuous wavelet transformation,then the energy spectrum entropy describing quantitatively vibration signals varying with time was calculated along the time axis, the impact vibrations of bearings with different faults varied with time at different levels,and their time-wavelet enery spectrum entropies were different.To identify the fault pattern and the working condition of a bearing,the time-wavelet enery spectrum entropies of different fault signals could be taken as input vectors of a support vector machine.Practical examples showed that the proposed method can be used to diagnose efficiently faults of rolling element bearings.%针对轴承振动信号中存在周期性冲击这一现象，提出了时间-小波能量谱熵的计算方法，用于滚动轴承的故障诊断。首先构造脉冲小波，采用连续小波变换的方法得到时间域内小波能量谱，再沿时间轴计算能量谱熵，定量描述振动信号沿时间的分布情况，不同故障下轴承的冲击振动随时间变化程度不同，其时间-小波能量谱熵值也就不同。将不同故障轴承信号的时间-小波能量谱熵作为向量特征输入建立支持向量机，实现了对轴承的工作状态和故障类型的判断。实验结果表明，时间-小波能量谱熵可以有效地对滚动轴承进行故障诊断。