【作者】 徐俊起；

【导师】 钱清泉；

【作者基本信息】 西南交通大学 ， 轨道交通电气化与信息技术， 2020， 博士

【摘要】 悬浮系统是EMS磁浮列车的关键系统,依靠电磁铁和钢制轨道之间的吸力使车辆保持无接触悬浮状态,是典型的开环不稳定系统,必须施加反馈控制使之稳定。此外,在车辆悬浮过程中系统具有非线性动态特性,容易受到轨道不平顺、牵引电机法向力、车辆气动载荷、机械制动、信号原因产生的扰动力等外部干扰以及上述综合因素产生的内部耦合扰动的影响。磁浮列车悬浮架是在多点悬浮系统共同支撑作用下实现悬浮功能的,如何克服外界干扰及内部耦合扰动问题,并实现各悬浮点协同输出给悬浮控制器的设计带来了非常大的挑战。近年来,针对EMS型中低速磁浮列车悬浮控制系统的研究已取得众多研究成果,但仍存在以下问题与不足:1)单点悬浮系统控制器多基于电流反馈设计,控制参数稳定域较小,缺少对基于磁通密度反馈控制方法的探索;2)在单点悬浮系统建模过程中,往往忽略多悬浮点之间的耦合扰动作用,缺少对多点悬浮系统内部耦合扰动进行抑制的研究;3)对于具有两个或以上独立控制回路的电磁铁,缺少电磁铁多点悬浮系统之间的协同控制研究;4)对于悬浮架两侧的两个电磁铁,缺少悬浮架多点悬浮系统之间的协同控制研究。本文选择EMS型中低速磁浮列车悬浮系统为具体研究对象,针对上述问题和挑战,对磁通密度反馈自适应滑模控制、特征建模及耦合扰动抑制、H_∞控制器设计、多点悬浮系统协同控制等解决方案进行了深入研究,具体工作及贡献如下:1)建立了基于磁通密度的单点悬浮系统动力学模型,设计了电流型和电压型相结合的混合磁通密度观测器,提出了基于磁通密度反馈的自适应滑模控制器。建立了基于d SPACE系统的半实物仿真试验平台,通过仿真和试验,对比了该控制器与PID控制器响应效果,验证了基于自适应滑模控制器的抗干扰性能。(第3章)2)提出了考虑多点悬浮系统耦合干扰的单点悬浮系统特征模型与扰动抑制方法。将悬浮系统一般动力学模型转化为以悬浮间隙为控制目标的特征模型,采用带有遗忘因子的最小二乘法进行特征模型系数辨识,计算各系数估计值范围,在广义预测控制方法(GPC)的基础上得到改进型广义预测控制方法(JGPC),通过仿真和试验对比,验证了该方法对于抑制内部耦合扰动的有效性。(第4章)3)为优化多悬浮点(多点悬浮系统)共同作用下的悬浮性能,研究了悬浮架单侧电磁铁多点悬浮系统协同控制方法。针对各个单点悬浮系统采用H_∞控制算法提高系统抗干扰性及鲁棒性;通过仿真比较基于磁通密度反馈自适应滑模控制器、基于特征建模的JPGC控制器、H_∞控制器和传统PID控制器的抗干扰性能,选择抗干扰性能最优的控制策略作为单点悬浮系统的基础控制方案;根据多点悬浮系统动力学方程得到开环状态空间方程,通过对悬浮间隙、间隙变化速度进行交叉耦合,协同悬浮间隙输出,减小和避免多点悬浮系统内部的耦合扰动,提高控制精度和抗干扰能力;对交叉耦合控制器的输出进行同步误差分析,确定系统稳定性。数值仿真表明,协同控制算法对于多点悬浮系统的抗干扰能力的提升具有较为明显的效果。(第5章)4)在电磁铁多点悬浮系统协同控制策略的基础上,通过相邻交叉耦合同步控制算法对悬浮架输出同步性进行协调,从而达到进一步提升悬浮系统稳定性和抗干扰能力的目的。建立了基于四点悬浮系统的单悬浮架试验平台,通过数值仿真和试验验证了当悬浮架的某一悬浮点受到冲击力干扰发生间隙偏离时,协同控制系统能够及时调整相对误差,达到改善悬浮架整体悬浮性能,提升悬浮架综合抗干扰能力的目的。(第6章)更多还原

【Abstract】 The suspension system is the key system of EMS maglev train.It depends on the suction between electromagnet and steel track to keep the vehicle in contactless suspension state.It is a typical open-loop unstable system,which must be stabilized by feedback control.In addition,in the process of vehicle suspension,the system has nonlinear dynamic characteristics,which is easy to be affected by external interference such as track irregularity,traction motor normal force,vehicle aerodynamic load,mechanical braking,disturbance force caused by signal,and internal coupling disturbance caused by the above comprehensive factors.The maglev suspension frame realizes the levitation function under the common support of multi-point suspension system.How to overcome the external disturbance and internal coupling disturbance and realize the coordinated output of each levitation point brings a great challenge to the design of suspension controller.In recent years,many achievements have been made in the research of EMS type suspension control systems of medium and low speed maglev trans,but the problems and shortcomings still exist as follows: 1)The controller design of single point suspension system is mostly based on current feedback,and the stable region of control parameters is small,which lacks the exploration of the control method based on flux density feedback;2)In the model of single-point suspension system,the coupling disturbance between multi coils is often ignored,and the research on restraining the coupling disturbance in multi-point suspension system is lacking;3)For the electromagnet with two or more independent control loops,the cooperative control research between the multi-point suspension system of electromagnet is lacking;4)For the two electromagnets on both sides of the suspension chassis,there is few research on the cooperative control between the multi-point suspension system of the suspension chassis.In this paper,EMS type medium and low speed maglev train suspension system is selected as the specific research object.Aiming at the above problems and challenges,the adaptive sliding mode control with flux density feedback,feature modeling and coupling disturbance suppression,H∞ controller design,multi-point suspension system cooperative control and other solutions are studied in depth.The specific work and contributions are as follows:1.A dynamic model of single point suspension system based on flux density is established.A hybrid flux density observer is designed,which combines current mode and voltage mode.An adaptive sliding mode controller based on flux density feedback is proposed.A hardware in the loop simulation platform based on d SPACE system is established.The response effects of the proposed controller and PID controller are compared by simulations and experiments,and the anti-disturbance performance of the adaptive sliding mode controller is verified.(Chapter 3)2.The characteristic model and disturbance suppression method of a single point suspension system considering the coupling interference of the multi-point suspension system are proposed.The general dynamic model of the suspension system is transformed into the characteristic model,the latter,taking the suspension gap as the control target.The least square method with forgetting factor is used to identify the characteristic model coefficients and calculate the estimated range of each coefficient.The improved generalized predictive control method(JGPC)is obtained based on the generalized predictive control method(GPC).The effectiveness of the method to suppress the internal coupling disturbance is verified by simulations and experiments.(Chapter 4)3.In order to optimize the suspension performance of multi coil(multi-point suspension system),the cooperative control method of single side electromagnet multi-point suspension system is studied.H∞ control algorithm is used to improve the anti-disturbance and robustness of each single point suspension system.The anti-disturbance performance of adaptive sliding mode controller based on flux density feedback,JGPC controller based on characteristic model,H∞ controller and traditional PID controller are compared by simulations,and the control strategy with the best anti-disturbance performance is selected as the basic control scheme of single point suspension system;According to the dynamic equation of multi-point suspension system,the open-loop state space equation is obtained.By cross coupling the suspension airgap and the change speed of the airgap,and cooperating with the output of the suspension airgap,the coupling disturbance inside the multi-point suspension system is reduced and avoided,and the control accuracy and anti-disturbance ability are improved.The synchronous error analysis of the output of the cross coupling controller is carried out to determine the stability of the system.The numerical simulation results show that the cooperative control algorithm has obvious effect on improving the anti-disturbance ability of the multi-point suspension system.(Chapter 5)4.Based on the cooperative control strategy of the electromagnet multi-point suspension system,the output synchronization of the suspension chassis is coordinated by the adjacent cross coupling synchronous control algorithm,so as to further improve the stability and anti-disturbance ability of the suspension system.Based on the four-points suspension system,a single suspension chassis experiment platform is established.It is verified that when a suspension point of the suspension chassis is disturbed by the impact force and the airgap deviates,the cooperative control system can adjust the relative error in time,so as to improve the overall suspension performance of the suspension frame and enhance the comprehensive anti-disturbance ability of the suspension chassis.(Chapter 6)更多还原