Research On Design And Control Technology Of Super High Speed Suspension System

In recent years,the ground super high speed systems,such as electromagnetic emission,high speed sled,super high speed rail and so on,have become research hotspot.In order to overcome the bottlenecks and shortcomings of wear,vibration,speed limit,low efficiency and high cost existing in wheel-rail or slider support and rocket engine propulsion,the electromagnetic induction principle is used to realize contactless support through magnetic levitation system and controllable speed propulsion through electromagnetic propulsion system,to design a safer,smoother,faster and lower cost super high speed system.In this paper,the characteristic analysis,structure design,control method and realization of the super high speed suspension system are studied based on the overall structure of electromagnetic propulsion and suspension guidance.The Main work includes:Firstly,high speed sled is used as an application object to analyze the demand of super high speed systems,and to clarify the performance indicators required for super high speed suspension and electromagnetic propulsion systems.The analysis and comparison of the suspension propulsion structure of TR high speed maglev system,Japan JR superconducting maglev system and Magplane permanent magnet maglev system show that EDS passive suspension structure is simple and reliable,the suspension stiffness is large,and the suspension force increases with speed increases,which is able to provide sufficient suspension force to the super high speed system.However,the EDS suspension structure with zero damping critical stability,is prone to oscillation,and has the possibility of divergence.The existing technical schemes have some limitations and cannot fully meet the requirements of the super high speed suspension and propulsion system.Secondly,the performance of the EMS electromagnetic suspension structure is controllable,and the influence of the eddy current effect can be controlled within a reasonable range through structural optimization.The EMS suspension structure is combined with the EDS suspension for super high speed suspension.The advantages are complementary to meet the requirements of suspension capacity.At the same time,combined with the air core superconducting linear synchronous motor,a structurally feasible super high speed suspension and propulsion system structure scheme is proposed,and the proposed structure scheme can meet the operational requirements of super high speed systems.Then,the EDS-EMS hybrid suspension structure model of super high speed suspension system is established.Which is a nonlinear,time varying,coupled,uncertain and disturbance complex system.The linear model is observable and controllable.When the moving speed is high enough,the EDS-EMS hybrid suspension system is open loop stable,but the EMS suspension system needs to be actively controlled to improve the critical stability characteristics of the EDS suspension structure and improve damping and anti-interference ability of the EDS-EMS hybrid suspension system.Using PID control,based on the extremum seeking algorithm,optimizing PID control parameters online,to adapt to load changes and disturbance effects,which can basically meet the system requirements.However,limited by the optimization speed and accuracy of the extremum seeking PID algorithm,the PID control based on the extremum seeking can not fully satisfy the control demand of load and disturbance change of super high speed system.Finally,an improved ESO(Extended State Observer)is proposed by iteratively calculating the observation errors of each state for feedback.The proposed observer has the advantages of simple structure,low hypothesis requirement and easy judgment,clear convergence condition,simple parameter debugging and easy engineering application.ADRC(Active Disturbance Rejection Controller)is designed based on the ESO feedback.The observation error and tracking error can converge to a small enough neighborhood.Simulation and experimental results show that the ADRC based on the proposed ESO can make the ultra-high speed suspension system convergent and stable.The super high speed suspension system is a system with extremely complicated structure and high operation requirements.So far,there is no clear verification of feasible technical solutions,the research is still in its infancy,and many key technologies need to be studied and broken through.The research content of this paper is the first time in China and the research results of this paper lay the foundation for super high speed emission and magnetic levitation traffic technology in China.