轨道不平顺激扰下机车传动齿轮振动特性研究

Research on vibration characteristics of locomotive transmission gear under track irregularity

为研究轨道不平顺激扰下机车传动齿轮的振动特性,采用Simpack软件建立机车动力学模型以仿真获取轨道对轮对的反作用力矩,并建立机车齿轮传动系统的集中参数动力学模型。以齿轮时变啮合刚度为内部激励、轨道对轮对的反作用力矩为外部激励,仿真分析机车传动齿轮在变载荷下的振动特性。结果表明,轨道不平顺激扰下齿轮的低频位移响应与载荷波动趋势一致;故障齿轮的故障特征频率与啮合频率处均存在以载荷主频为间隔的边频带,健康齿轮的啮合频率处也存在该边频带,这将对故障的诊断造成干扰。并且当载荷主频与故障特征频率或啮合频率一致时系统会发生共振现象,将严重影响机车运行的平稳性和安全性。研究结论揭示了轨道不平顺激扰对机车齿轮传动系统的影响机理,可为机车齿轮动力学研究与机车齿轮箱故障诊断工作提供理论基础。

In order to study the vibration characteristics of the locomotive transmission gear under the disturbance of track irregularities,the simulation of track-to-wheelset reaction torque is carried out by establishing the locomotive dynamic model in Simpack software,and the centralized parameter dynamic model of the locomotive gear transmission system was established.Meanwhile,the vibration characteristics of the locomotive transmission gear under variable load is analyzed,which internal and external excitation is the timevarying mesh stiffness and track-to-wheelset reaction torque respectively.The results show that the lowfrequency displacement response of the gear is consistent with the trend of load fluctuation under the disturbance of track irregularities.Meanwhile,the fault characteristic frequency and mesh frequency of the faulty gear have sidebands separated by the main frequency of the load,and the phenomenon also exists in healthy gear’s frequency spectrum,which will cause interference to the fault diagnosis of the gear.Moreover,the resonance phenomenon will occur when the main frequency of the load is consistent with the characteristic frequency or mesh frequency of the faulty gear,which will affect the stability and safety of the locomotive seriously.The conclusion reveals the influence mechanism of track irregularity disturbance on the locomotive gear transmission system,which provides theoretical basis and guidance for locomotive gear dynamics research and locomotive gearbox fault diagnosis.