机车传动系统扭转与轮对纵向耦合振动稳定性

Torsional-longitudinal coupling vibration stability of drive system for locomotive

为研究机车打滑时传动系统扭转与轮对纵向耦合运动作用下传动系统的稳定性,建立了机车单轮对传动系统动力学模型,考虑了轮对回转与纵向振动自由度,对非线性系统微分方程在平衡点附近线性化,并根据线性化系统在状态空间中的特征值判断系统的稳定性,绘制了振动系统临界稳定曲线。分析结果表明:由于轮轨粘着系数的负斜率,传动系统的扭转振动与轮对的纵向振动为不稳定的自激振动,两者与轮对运行速度和轴重有关,速度越大,轴重越小,振动越稳定,因此,传动系统的扭转与轮对的纵向阻尼能很好抑制这种自激振动。

In order to investigate the stability of drive system under torsional-longitudinal coupling vibration for locomotive in slippage process, a dynamics model of drive system with single wheelset was set up, the torsional and longitudinal vibration freedoms of the wheelset were taken into account. The nonlinear differential equations of drive system vibration were linearized at the balance point, and its eigenvalues were calculated to judge the stability of the system, whose critical vibration curves were gained. Analysis result shows that the torsional vibration of drive system and the longitudinal vibration of wheelset are self-excited vibrations because of the negative slope of adhesion curve between wheel and rail, and their stabilities depend on wheelset^s speed and axle load. The higher the velocity is and the lower the axle load is, the stabler the vibrations are. So the damps of torsional and longitudinal vibrations are able to suppress the unstable vibrations. 1 tab, 5 figs, 8 refs.