齿轮-转子-轴承系统复合故障振动特性研究

Research of Vibration Characteristics of Gear-rotor-bearing System with Compound Faults

针对齿轮-转子-轴承系统发生复合故障时齿轮副振动响应,结合齿轮副模型和滚子轴承模型,基于拉格朗日方程建立了36自由度的齿轮-转子-轴承系统耦合振型,设定齿轮副主动轮剥落和轴承表面损伤复合故障,研究了复合故障下齿轮副的振动响应。结果表明,在健康的齿轮-转子-轴承系统振动响应下,系统振动时域幅值较为均匀,振动频谱主要为轴承外圈特征频率和齿轮副啮合频率;当齿轮副发生剥落单故障时,系统振动频谱上出现啮合频率与转轴频率调制生成的边频带;当齿轮-转子-轴承系统发生复合故障时,系统振动时域上的振动幅值增大,振动愈加复杂,频域信号调制现象严重,而且调制生成的信号幅值增大,但在其振动频域上可以找到其故障频率以及调制生成的谐波频率,以此可以判断系统的故障类型。

For the vibration response of gear-rotor-bearing system with compound faults,after the gear pair model and ball bearing model are combined,a coupling vibration model of gear-rotor-bearing system with 36 degrees of freedom based on the Lagrange equation is built,and the spalling defect on the driving gear and surface damage compound faults of bearings are set to study the vibration response of gear pair under compound faults.The results show that the vibration amplitude of the healthy gearing-rotor-bearing system is relatively uniform on time domain,and the vibration spectrum mainly consists of the characteristic frequencies of the bearing outer raceway,as well as the meshing frequencies of the gear pair.When there is a spalling single fault on the gear pair,the sidebands generated by the frequency modulation of the rotating shaft and meshing fre⁃quencies can be found.When compound faults of the gear-rotor-bearing system occurs,the amplitude of sys⁃tem vibration on the time domain increase and the vibration are becoming more complicated.The modulation phenomenon is serious on frequency domain,and the amptitude of the signal generated by modulation increas⁃es.However,the fault frequencies and harmonic frequencies can be found in the vibration frequency domain,which can determine fault types of system.