Research On Sliding Mode Variable Structure Control Of Controlled Excitation Linear Synchronous Motor

The thesis"Research on Sliding Mode Variable Structure Control of Controllable Excitation Linear Synchronous Motor"is based on the project of National Natural Science Foundation of China"Study on Operation Mechanism and Control Strategy of Controllable Excitation Linear Synchronous Motor Maglev Feeding Platform(51575363)".Solve the control problem of the controllable excitation linear synchronous motor under the action of uncertainty external disturbance.The main contents of the thesis are as follows:(1)Research on the structure,working mechanism and mathematical model of controllable excitation linear synchronous motor.The mathematical model of controllable excitation linear synchronous motor is established in d-q synchronous rotating coordinate system,the analytical expressions of electromagnetic thrust and magnetic levitation force are derived,and the main factors affecting electromagnetic thrust and magnetic levitation force are analyzed.For the problem of electromagnetic coupling between feed subsystem and suspension subsystem,i_d=0 control is used to weaken the coupling term to the greatest extent,so as to reduce the difficulty of control.(2)Design of sliding mode controller for feed subsystem of controllable excitation linear synchronous motor.Controllable excitation linear synchronous motor is in the state of magnetic levitation,which is vulnerable to parameter perturbation and external uncertainties.To solve this problem,a sliding mode controller with strong robustness in the whole process is designed.At the same time,hyperbolic tangent function is used instead of symbolic function to soften the control input signal and reduce the chattering of the system.Finally,the simulation model of the feed subsystem of the controllable excitation linear synchronous motor is built,and the control system is simulated.(3)Design of Global Integral Terminal Sliding Mode Controller for feed subsystem of controllable excitation linear synchronous motor.In order to further improve the robustness and rapidity of the feed subsystem of the controllable excitation linear synchronous motor and reduce the chattering of the system.The integral Terminal sliding surface and the reaching law with attenuation factor are designed.RBF neural network is used to observe the disturbance signal and feed forward the observation results.A theorem describing the control law of the system is proposed,and an appropriate Lyapunov function is constructed to prove the theorem mathematically.Finally,the control strategy is verified by computer simulation.(4)Research on the coupling mechanism of the control system of controllable excitation linear synchronous motor.The simulation model of the control system of the controllable excitation linear synchronous motor is built,which includes two parts:the horizontal feed subsystem and the suspension subsystem.The starting and loading process of the control system of the controllable excitation linear synchronous motor are simulated,and the coupling mechanism of the system is observed and analyzed.Finally,the work of this thesis is summarized and combed,which provides reference for the follow-up research of controllable excitation linear synchronous motor.