裂纹故障对行星齿轮传动系统动力学特性的影响

针对行星传动装置动态特性复杂、故障率高的问题,拟从动力学角度探索行星传动系统的故障机理。采用改进能量法,仿真分析正常与含裂纹齿轮时变啮合刚度,考虑时变啮合参数影响,运用集中参数法建立了行星齿轮传动系统动力学模型;求解得到了正常与含故障齿轮传动系统动态响应,并对比分析了裂纹故障对动力学特性的影响;通过台架实验,分析了裂纹故障对齿轮动态响应的影响,结合小波分析与EEMD方法对齿轮振动信号进行频谱分析,并对比分析了正常与故障齿轮的频域特性差异,揭示了行星齿轮传动系统的故障机理。研究表明:所建立的动力学模型精度较高,能够很好地描述含故障齿轮传动系统的动力学特性;由于裂纹故障引起传动系统振动的调制效应,导致在齿轮啮合频率附近出现明显边频带,故障齿轮箱的振动能量主要集中在高频段。

Influence of crack fault on the dynamical characteristics of a planetary gear transmission system

In view of the complex dynamic characteristics and high failure rate of planetary gearboxes, the failure mechanism of a transmission system was explored from the aspect of dynamics.The modified energy method was used to simulate the time-varying meshing stiffness of normal and cracked gears.The dynamic model of the planetary gear transmission system was established by using the lumped parameter method and considering the time-varying meshing parameters.The dynamical responses of the system in the normal and fault gear states were obtained, and the influence of crack failure on its dynamical characteristics was analyzed.The influence of crack fault on the dynamic responses of the planetary gears was investigated by gearbox bench tests.The frequency spectrum of the gear vibration signal was analyzed with the wavelet decomposition and EEMD method.The frequency domain characteristics of the system in the normal and fault gear states were compared, according to which the fault mechanism of the planetary gear transmission system was revealed.The results show that the dynamical model has high precision and can well describe the dynamic characteristics of the planetary gears system with faults.The modulation effect of the vibration of the transmission system caused by crack fault will lead to the sidebands near the gear meshing frequency, and the vibration energy of the fault gearbox is mainly concentrated in high frequency region.