考虑悬浮系统影响的高速磁悬浮列车牵引控制策略

Traction Control Strategy of High-Speed Maglev Considering the Influence of Suspension System

常导电磁式高速磁悬浮列车采用长定子直线同步电机驱动,电机的励磁磁极同时也是悬浮电磁铁,车辆的牵引力和悬浮力存在严重的非线性耦合关系,运行过程中悬浮系统的调节会对牵引系统造成影响,引起牵引力波动。该文建立考虑悬浮系统影响的长定子直线同步电机数学模型,针对牵引力波动问题,提出一种基于磁链观测的控制策略,该策略基于扩展反电动势法来观测磁链,通过将磁链参数应用于速度环和电流环,在线调整定子q轴电流从而抑制由悬浮系统引起的低频牵引力波动。但该策略在低速时磁链观测存在误差、性能受限,在此基础上提出结合自抗扰和磁链观测的复合控制策略,通过扩张状态观测器补偿磁链观测误差以及其余扰动。硬件在环实验结果表明,该控制策略有效地抑制了悬浮系统影响造成的牵引力波动,提高了磁悬浮列车的抗负载扰动能力和系统动态性能。

The electromagnetic suspension(EMS)type high-speed maglev vehicleis driven by the long-stator linear synchronous motor.The excitation magnetic poles of motor areal so the electromagnets of suspension system,thus there is a serious nonlinear coupling relationship between the traction and levitation force of vehicle.The adjustment of the suspension system during operation will affect the traction system,which leads to traction force fluctuations.In this paper,a mathematical model of linear synchronous motor considering the influence of the suspension system is established.Aiming at the problem of traction fluctuations,a control strategy based on flux observation is proposed,which uses the extended electromotive force(EEMF)method to observe the flux.By applying the flux parameter to the speed loop and current loop,the q-axis current can be adjusted online to suppress the low-frequency traction fluctuation caused by the suspension system.However,the performance of this strategy is limited when the flux observation error exists at low speed region.Accordingly,a composite control strategy combining active disturbance rejection and flux observation algorithm is proposed,which compensates the flux observation error and other disturbances through the extend state observer(ESO).The results of hardware-in-the-loop(HIL)experiments show that the control strategy effectively suppresses the traction fluctuation caused by the influence of the suspension system,and improves the anti-load disturbance ability and dynamic performance.