直线电机振动特性对车轮多边形问题的影响研究

Effects of the vibration characteristics of linear motors on the polygon wheel problem

针对国内某地铁车辆因车轮多边形造成舒适性差的问题展开动力学仿真和线路测试研究。理论上简要分析了车轮多边形产生的原因并建立地铁车辆动力学模型,计算得到转向架各部件的振动固有频率,并发现车辆平稳性在40 km/h速度下异常恶劣。建立以轨道不平顺为输入、电机位移为输出传递函数,分析了40 km/h速度下车轮多边形产生的外部激励43.6 Hz与直线电机垂向固有频率接近从而导致电机发生共振,进一步加剧了车轮多边形恶化。线路跟踪实验表明,车体上的平稳性指标同样在40 km/h时异常恶化,恶化程度随车轮多边形波深增大而加剧。归纳提出以异常振动速度为切入点,对车轮多边形问题分析的仿真和线路实验方法。最后对直线电机悬挂参数进行优化,消除剧烈振动,提高了乘坐舒适性。

Aiming at analysing the bad ride comfort caused by the polygon wheel of a domestic subway vehicle,numerical simulations and field tests were carried out. The reason of polygon wheel was analyzed theoretically. A dynamic model for the subway vehicle was established and the natural frequencies of bogie components were calculated. The simulations show that the vehicle ride comfort is irregularly bad at 40 km/h. The transfer function from the track irregularity to the motor displacement was established and the results show that polygon wheels produce external excitation of 43 Hz at 40 km/h which is close to the vertical vibration natural frequency of the linear motor,causing the resonance of motor and the development of polygon wheel. The field tests show that the ride comfort tested on the car body is also irregularly bad at 40 km/h and it tends to deterioration with the growth of polygon wave depth. The methods for simulations and field tests for studying the polygon wheel effect,featured with the irregular vibration velocity as a key factor,were summarized. Finally,the parameters of motor suspension were optimized to eliminate the severe vibration and to improve the ride comfort.