Research On Performance Optimization Of Magnetic Levitation System In High Speed Maglev Train

With the opening of many commercial lines at home and abroad,maglev train has received considerably increasing attention and been an active traffic field in recent years.As an entirely new mode of transport without wheels,the high-speed maglev train is of great significance to solve the problem of rapid traffic between big cities and to establish and improve the efficient and high-speed passenger transport system in China.In this thesis,the performance optimization of the magnetic levitation system of the 600km/h high speed maglev train is studied.The mathematical model of magnetic levitation system in high speed maglev is established,and the nominal controller is designed according to the characteristics of the model.Due to the influence of various disturbances during the long-term operation of high-speed maglev train,the performance of magnetic levitation system begins to degrade.In order to analyze and study the performance of the magnetic levitation system in the process of train operation,the dynamic performance evaluation index suitable for the magnetic levitation system is proposed.The performance degradation of the magnetic levitation system is analyzed and discussed in combination with the disturbance factors that cause the performance degradation of the magnetic levitation system in the engineering.In order to optimize and improve the performance of the magnetic levitation system in the process of train operation,a framework based on Youla parameterization is proposed.At the same time,an on-line optimization algorithm based on learning is also designed.Based on the engineering application of the magnetic levitation system of high speed maglev train,the suspension controller of high speed maglev train is designed and developed,and the basic suspension performance test is completed by utilizing the double suspension frame test platform.The main achievements and innovations are as follows:(1)In the light of the structure of magnetic levitation system in high speed maglev,a nonlinear mathematical model of magnetic levitation system is established.Combined with the working principle and basic structure of the magnetic levitation system,the characteristics of model are analyzed and the nominal controller is designed.The nonlinear magnetic levitation system model is built by Simulink and the nominal controller is simulated.The nominal performance of the magnetic levitation system is evaluated objectively.Because of the defect of adopting nominal performance index to evaluate the performance of magnetic levitation system in operation,a dynamic performance evaluation index suitable for magnetic levitation system is proposed,which lays a foundation for the following chapters.(2)In view of the dynamic characteristics of the magnetic levitation system during the operation of the high speed maglev train,the common disturbance factors causing the performance degradation of the magnetic levitation system are summarized and analyzed.Aiming at deterministic disturbances such as load variation and line curve variation,the adverse effects of the deterministic disturbances on the performance of the magnetic levitation system and the corresponding control and optimization schemes are analyzed and discussed.In view of the uncertain disturbances such as random track irregularity and tangential torsional angle change of beam end,the degradation of the performance of the magnetic levitation system is analyzed and discussed in this chapter.(3)In order to optimize and improve the performance of the magnetic levitation system during the operation of high speed maglev train,a framework for optimizing the performance of magnetic levitation system based on Youla parameterization is proposed.This framework is able to monitor the state change of the system when the disturbance occurs by designing the residual generator based on the observer without changing the main structure of the existing controller,and realize the dynamic compensation of the existing controller by dynamically adjusting the Youla parameter matrix.(4)In order to realize on-line optimization of magnetic levitation system performance of high speed maglev train,an on-line optimization algorithm based on residual is designed.The stability of the algorithm is demonstrated.By utilizing the optimization framework of magnetic levitation system performance based on Youla parameterization,the on-line updating rule of parameter vector of Youla parameter matrix is achieved,and the on-line optimization of magnetic levitation system performance is realized.Through the simulation of the on-line optimization of the magnetic levitation system performance under the disturbance,the effectiveness of the on-line optimization algorithm is verified.(5)Focusing on the engineering application of the magnetic levitation system of high-speed maglev train,the hardware circuit of the suspension controller of high speed maglev train is designed firstly.Secondly,the software architecture of the suspension controller based on dual DSP core processing chip is realized.Thus,the suspension controller of high-speed maglev train is designed and developed.Finally,a high speed maglev double suspension test platform is built,and a series of magnetic levitation system performance tests are carried out by using the double suspension test platform,which verifies the basic functions of the developed suspension controller.The above achievements and innovations are helpful for the 600 km/h high speed maglev vehicle in China.The results of this thesis have reference value for optimizing and improving the performance of magnetic levitation system in the long-term operation of high speed maglev train,and contribute to the commercial application of high speed maglev train with a speed of 600 km/h in China.