机车打滑时传动系统的自激扭转振动

Self-Excited Torsional Vibrations of Drive System of Locomotive under Slippage

为研究机车发生打滑时传动系统扭转振动,针对机车单轮对传动系统,考虑轮对以及电机与轮对间的扭转刚度,建立了简化的机车传动系统扭转振动方程.当轮轨间的平均蠕滑率超过临界蠕滑率时,产生了传动系统扭转振动极限环,表明传动系统产生了自激振动.对不同工况下传动系统扭转振动频率的计算结果表明,当自激振动发生时,系统的扭转振动频率与其扭转固有频率一致.因此,检测轮对的扭转振动频率可以判断车轮是否打滑.

A simplified model for torsional vibrations of a single wheel-set drive system was used to study torsional vibrations of a locomotive under slippage. In the model, torsional stiffness of the shaft of a wheel set and that between the traction motor and the wheel-set were taken into account. The phase trajectories of the torsional vibrations are a set of stable limit cycles, signifying self-excited vibrations when the average wheel-rail creepage is over the critical value. Frequencies of torsional vibrations with different operating modes were calculated. The results show that the vibration frequency is in accordance with the natural frequency of the drive system when self-excited vibrations happen. Therefore, analyzing the vibration frequency of wheel-sets is a measure to identify wheel-rail slippage.