Research On Control Robustness Of Permanent Magnet Suspension System With Controllable Magnetic Circuit

There are many classifications of magnetic levitation technology.Among them,the permanent magnetic levitation system has many advantages such as energy-saving,no heat,no noise,and no friction loss.The permanent magnetic levitation technology is loved by more and more scientists.However,with the development of permanent magnetic levitation technology,the working environment faced by permanent magnetic levitation systems is becoming more and more complex.To improve the robustness of permanent magnetic levitation systems,this thesis conducts robust research on controllable magnetic circuit permanent magnetic levitation systems.The permanent magnetic levitation system used in this article is to adjust the levitation force according to the method of adjusting the magnetic circuit.And the permanent magnetic levitation system is a typical nonlinear system.When the permanent magnetic levitation system is disturbed,the system is easy to lose stability.To improve the robustness of the permanent magnetic levitation system,this thesis adopts PID control in the single-point permanent magnetic levitation system to make the system levitation stable.By changing the controller in the system,the designed controller is used to improve the robustness of the permanent magnetic levitation system.First,the article derives the linearized system model of the controllable magnetic circuit type single-point permanent magnetic levitation system,and proves the controllability and observability of the permanent magnetic levitation system,and conducts a step response analysis of the open-loop system of the permanent magnetic levitation system.The stability of the permanent magnetic levitation system is analyzed in the time domain and frequency domain.Then by designing a robust auto-disturbance rejection controller,the estimated value of the system can be observed in real-time during operation and the internal and external disturbances of the system can be compensated,which can effectively improve the anti-disturbance characteristics of the permanent magnetic levitation system;in order to be effective In response to the change of the error between the expected value and the actual value of the permanent magnetic levitation system every time the permanent magnetic levitation system is stably suspended,a variable universe fuzzy PID controller is designed to expand the variation range when responding to errors;in order to improve the control performance of the permanent magnetic levitation system,the design The fractional-order PID controller is approximated by Oustaloup filter,and the genetic algorithm in the intelligent optimization algorithm is used for parameter setting and optimization to improve the robustness of the permanent magnet levitation system.The designed controller is simulated and analyzed.Finally,based on the single-point permanent magnetic levitation system of the controllable magnetic circuit,the controller designed by MATLAB is used for simulation analysis.The results of simulation analysis show that the controller designed in this thesis can quickly restore stability to the permanent magnetic levitation system and make the permanent magnetic levitation system more robust.And the variable universe fuzzy PID controller is tested on the single-point permanent magnetic levitation system test bench.The experimental results prove that the variable universe fuzzy PID controller can improve the robustness of the permanent magnetic levitation system.