基于电机动力吸振的高速列车蛇行运动控制

复兴号CR400BF高速动车组动力转向架的牵引电机采用特有的四点弹性架悬方式, 在电机和构架之间安装有横向液压减振器和横向止挡, 首次采用牵引电机作为动力吸振器来控制转向架蛇行运动稳定性和蛇行频率, 从而避免引起车体弹性模态共振; 考虑悬挂参数和轮轨接触非线性, 建立了复兴号动车组非线性多刚体动力学仿真模型, 通过悬挂模态计算和动力学时域仿真, 分析了关键参数对动车蛇行运动的影响规律; 基于将电机作为动力吸振器的原理, 优化了电机节点横向刚度和横向减振器阻尼; 考虑动车组运营中的轮轨匹配随机因素, 组合400种轮轨随机匹配状态, 仿真分析了动车的动力学性能; 开展动车组长期线路动力学跟踪试验, 研究了动力转向架蛇行运动演变规律。仿真与试验结果表明: 牵引电机弹性架悬下的构架横向加速度频谱图从以蛇行频率为主频的单峰值变化为主频在蛇行频率两侧的双峰值, 说明电机起到了动力吸振器的作用; 将电机作为动力吸振器能够提高动车蛇行运动稳定性, 具有不同等效锥度的典型轮轨匹配下非线性临界速度超过500 km·h^-1; 动车蛇行运动最高频率被控制在6 Hz附近, 远离车体中部菱形弹性模态频率8.5 Hz, 避免了转向架蛇行运动激起车体弹性共振; 动车组在轨道随机不平顺激扰下, 构架端部横向加速度小于0.5g, 平稳性指标小于2.5, 轮轴横向力和脱轨系数等运行安全性指标满足要求。

Hunting control of high-speed train using traction motor as dynamic absorber

The traction motor of power bogie of CR400BF Fuxing high-speed EMU adopted the unique four-point elastic suspension mode, and the transverse oil dampers and bump stops were installed between the motor and bogie frame. For the first time, the traction motors were used as dynamic absorbers to control the hunting stability and hunting frequency of the bogie, and further to avoid the elastic modal resonance of car body. Considering the nonlinearity of suspension parameters and wheel/rail contact, a nonlinear multi-body dynamics simulation model of Fuxing EMU was established. The influence of key parameters on the hunting was analyzed by the suspension modal calculation and dynamics time-domain simulation of power vehicle. Based on the principle of using the traction motor as a dynamic absorber, the lateral stiffness of motor node and the damping of oil damper were optimized. Considering the random wheel/rail matching factors in the EMU operation, 400 wheel/rail random matching states were combined to analyze the dynamics performances of the EMU. The long-term dynamics tracking test of the EMU on line was carried out, and the development of hunting phenomenon of power bogie was obtained. The simulation and test results show that the frequency spectrum of bogie frame's lateral acceleration under the motor's elastic suspension changes from a single peak with the hunting frequency as the main frequency to double peaks with the main frequency on both sides of the hunting frequency, which indicates that the motor acts as a dynamic absorber. Taking the motor as a mass damper can improve the hunting stability of motor vehicle. The nonlinear critical speeds under typical wheel/rail matchings with different equivalent conicities exceed 500 km·h-1. The highest hunting frequency of motor vehicle is around 6 Hz, which is far away from the diagonal distortion mode frequency 8.5 Hz of car body. Therefore, the elastic resonance of car body caused by the bogie hunting is avoided. Under the excitation of random track irregularity, the transverse acceleration at the end of bogie frame is less than 0.5g, the spelling index is less than 2.5, and the wheelset lateral force and derailment coefficient meet the requirements.