摘要
为研究采用主动横向悬挂的高速车辆系统Hopf分岔特性,建立整车横向简化7自由度非线性动力学模型,基于传统天棚控制原理提出天棚/地棚阻尼和刚度非线性控制律,即将二系横向减振器的理想主动力表示为车体或转向架横向位移和速度的三次多项式函数,理论研究状态反馈量和控制增益对车辆系统蛇行运动Hopf分岔速度、极限环幅值和频率的影响规律.结果表明:被动悬挂难以兼顾车辆一次和二次蛇行失稳工况;地棚阻尼和刚度控制律中一次项和三次项增益对一次蛇行分岔特性影响很小;优化地棚阻尼和刚度控制律一次项增益可提升二次蛇行失稳临界速度,其中地棚阻尼控制律提升效果更为显著;优化地棚阻尼控制律三次项增益可以显著降低极限环幅值且不改变蛇行频率,而地棚刚度三次项增益则不影响系统蛇行分岔特性;优化天棚阻尼和刚度控制律中一次项增益能够有效抑制一次蛇行,主要原因是改变了车体悬挂模态阻尼比和频率,然而天棚刚度控制会降低二次蛇行临界速度;综上,合理设计天棚/地棚阻尼和刚度控制律及参数,能够有效调控车辆系统分岔速度及极限环幅值.研究可为基于主动横向悬挂技术的动车组蛇行稳定性和运行平稳性协调控制研究提供理论依据和参考.
To study the Hopf bifurcation characteristics of high-speed vehicles with active lateral suspension,a 7DOFs nonlinear simplify dynamics model is established.Based on the traditional skyhook control principle,the nonlinear control strategy of skyhook/groundhook damping and stiffness control law is proposed,which means that the ideal active force of the lateral damper is expressed as a cubic polynomial function of the lateral vibration displacement or velocity of the vehicle carbody or the bogie.Theoretical study of the effects of the state feedback quantity and control gain on the Hopf bifurcation velocity,the limit cycle amplitude and the hunting motion frequency of the vehicle system.The results shows that the passive suspension parameters hardly balance the first hunting motion and the second hunting motion.The primary and cubic term gain of the groundhook damping and stiffness law have little influence on the bifurcation characteristics of the first hunting motion;Optimizing the primary and cubic term gain of the groundhook damping and stiffness law can increase the critical speed of second hunting motion and the effect of the groundhook damping law is more significantly;Increasing the cubic term gain of the groundhook damping law can significantly reduce the limit cycle amplitude without changing the frequency of hunting motion,and the cubic term gain of the groundhook stiffness law does not affect the bifurcation characteristics of second hunting motion;Increasing the primary term gain of the skyhook damping and stiffness law can effectively inhibit the first hunting motion,mainly because of changing the body suspension modal damping ratio and frequency,however,the skyhook stiffness low will reduce the critical speed of the second hunting motion;In conclusion,the reasonable design of skyhook/groundhook damping and stiffness control laws and their parameters can effectively regulate the bifurcation speed and limit cycle amplitude of the vehicle system.The study can provide theoretical basis and reference for the coordinated control of hunting motion stability and ride quality of the EMU based on active lateral suspension technology.
作者
刘沿修
石怀龙
曾京
寇云皓
武士栋
Liu Yanxiu;Shi Huailong;Zeng Jing;Kou Yunhao;Wu Shidong(State Key Laboratory of Rail Transit Vehicle System,Southwest Jiaotong University,Chengdu 610031,China)
出处
《力学学报》
EI
CAS
CSCD
北大核心
2024年第4期1088-1097,共10页
Chinese Journal of Theoretical and Applied Mechanics
基金
国家自然科学基金(52272406,U2034210)
轨道交通运载系统全国重点实验室自主课题(2024RVL-T13)资助项目。