基于MCKD和改进IESFOgram相结合的行星轴承外圈故障诊断

Planet bearing outer-race fault diagnosis based on MCKD and improved IESFOgram

针对行星齿轮箱中振动信号传递路径具有时变性和信号间相互耦合的问题,提出了基于最大相关峭度反卷积消噪技术(maximum correlated kurtosis deconvolution,MCKD)和特征优化图改进包络谱(improved envelope spectrum via feature optimisation-gram,IESFOgram)相结合的行星轴承外圈故障诊断方法。该方法使用MCKD技术对信号进行降噪处理,增强与行星轴承故障相关分量的能量幅值;采用改进IESFOgram提取轴承故障振动分量,再基于特征频率各阶次谐波频率与边带积分比值之和最大确定包含轴承故障信息最丰富的优化解调频带;最后包络谱分析辨识故障特征。通过对行星轴承外圈的实测数据分析,验证了所提方法的有效性。

In order to solve the problems that the vibration signal transmission path in the planetary gearboxes has time-varying and mutual coupling of vibration signals,a fault feature extraction method of planet bearing outer-race based on the maximum correlation kurtosis deconvolution(MCKD)and improved envelope spectrum via feature optimisation-gram(IESFOgram)were proposed.Firstly,the MCKD was used to suppress the interference of background noise and components outside the filtering band,and enhance the signal to noise ratio(SNR)of the component related to the planet bearing outer-race fault.Then,the planet bearing outer-race fault component could be extracted by the IESFOgram,and the optimal demodulation frequency could be determined based on the maximum value of sum of each order harmonic frequency of the characteristic frequency and the sideband integration ratio.Finally,fault features were extracted by envelope spectrum analysis.By analyzing measured signals of a planet bearing outer-race fault,it was proved that this method can effectively extract fault features of planet bearings.