支承松动的转子系统动力学模型及其故障诊断方法

针对滚动轴承转子系统支承松动故障 ,考虑了松动间隙的非线性情况 ,以转子动力学、Hertz接触理论和非线性动力学理论为基础 ,建立了转子系统的动力学模型。对转子系统动力学方程在松动故障和无故障情况下分别进行数值积分 ,得到两种情况下轴承座 (有故障时为松动端 )上的振动仿真信号。利用频谱和小波变换对所获振动信号进行了处理 ,并将结果进行了分析 ,得出小波变换不但能很好地诊断滚动轴承—转子系统的支承松动故障 ,而且比 Fourier变换在更低转速下诊断出转子系统的支承松动故障 

Dynamic Model of Rotor System with Support Loosening and its Diagnosis Method

Aiming at the specific features of the non-linear rolling bearing-rotor system with pedestal loosening at one support,the dynamics equations of rolling bearing-rotor system were derived using Hertz theory,non-linear dynamics and rotor dynamics,after taking into account the nonlinear condition of looseness.The dynamics equations were numerically integrated for cases with and without looseness,and the vibration signals were obtained for the two cases.The vibration signals were treated with the Fourier transformation and the wavelet transformation respectively.Comparing and analyzing the results,it can be seen that both methods can diagnose the support's loosening fault of the rolling bearing-rotor system effectively,however,the wavelet transformation can diagnose the fault at lower rotating speed,i.e.earlier than the Fourier transformation.The result presented can provide some reference for diagnosing the pedestal loosening fault.