高速动车组尾车横向晃动调查研究

某型号高速动车组运行过程中,尾车在新轮状态时出现持续晃动,但反向作头车运行时却不晃动。针对此问题,开展了不同线路表面状态下的车辆晃动特征测试,从悬挂系统振动传递特性、轮轨匹配状态,以及关键零部件性能检测等方面着手,确定了车体产生晃动的原因。结果表明,尾车横向晃动始于车辆高速通过个别道岔时刻,晃动发生后只能通过降速消除;将车轮踏面镟修为磨耗后踏面,能够显著缓解尾车晃动;晃动车辆抗蛇行减振器的静态阻尼力值偏大近100%,动态刚度亦偏大。基于车辆晃动机理,确认导致车辆晃动的激扰源于轮轨激励,即新轮与道岔处实际轮轨匹配等效锥度偏低,导致转向架蛇行频率与尾涡效应引起的车体摇头、滚摆模态频率相近;车辆二系回转刚度异常增大时,车辆晃动敏感性提高。经试验验证,提出通过控制抗蛇行减振器动态刚度进而降低车辆晃动敏感性的解决措施。

Investigation on Tail Vehicle Lateral Swaying of High-speed EMU

During the operation of a high-speed EMU train,the tail vehicle swayed continuously in the new wheel state,but it did not sway as the head vehicle running in the reverse direction.According to this problem,the vehicle swaying characteristics test under different line surface conditions is carried out,in order to determine the causes from the vibration transmission characteristics of suspension system,the wheel-rail matching status and the performance detection of key components.The results show that the tail vehicle lateral swaying starts when the vehicle passed through certain turnouts at high speed,and the swaying can only be eliminated by reducing the train speed,but the worn tread after re-profiling can significantly alleviate the swaying of the tail vehicle.Since the static damping value of swaying vehicle's anti-yaw damper is too large and close to nearly 100%,the dynamic stiffness is also too large.According to the swaying mechanism,it is confirmed that the excitement led to the vehicle swaying comes from wheel-rail excitation,namely,the actual wheel-rail matching equivalent conicity of the new wheel and the turnout is rather low.The result is that the bogie hunting frequency is similar to the rolling pendulum mode frequency and the car body shaking frequency caused by wake vortex effect.When the secondary rotation stiffness of the vehicle increases abnormally,the vehicle swaying sensitivity increases.Verified by test,a solution of controlling the dynamic stiffness of anti-yaw damper to reduce the vehicle swaying sensitivity is proposed.