Research On Predictive Control Of Arc Permanent Magnet Motor For Large-Aperture Astronomical Telescope

Arc Permanent Magnet Motor(APMM)has potential application prospects in the drive control system of large-aperture astronomical telescopes due to its simple structure,high power density,which is convenient for direct drive.In this paper,a double closed-loop predictive control system based on the principle of predictive control is designed for APMM.The load torque fluctuations and parameter mismatches have also been studied.In addition,a disturbance observer is designed to compensate.The basic structure and mathematical model of APMM are analyzed and the basic theory of predictive control is studied.Aiming at the arc motor predictive control system,the speed loop model predictive control and the current loop deadbeat predictive control are designed to form a cascaded double closedloop predictive control system.The performance is compared with the traditional PI control and single predictive loop control system.The speed tracking performance of the double closed-loop predictive control system proposed in this paper is better.Furthermore,a simulation model is built in MATLAB/Simulink to verify the feasibility of the proposed control system.In view of the influence of parameter mismatch and load torque fluctuations on control performance,a parameter disturbance sliding mode observer and a parameter disturbance internal model observer are designed to improve the immunity and robustness of the system,which is based on the principles of sliding mode control and internal model control.At the same time,the load torque internal model observer is designed to observe the change of load torque,which improves the anti-load disturbance ability of the system.A simulation model is built in MATLAB/Simulink,and the improved control strategy is simulated to verify the feasibility of the proposed strategy.Finally,the experimental platform of the APMM control system is built,the hardware circuit is designed and the experiment board is made.Meanwhile,the software control code is written based on the C language,and the upper computer interface is designed.The control performance of the proposed predictive control system is tested by means of the combination of software and hardware.The experimental results show that the improved strategy and predictive control method proposed in this paper can obtain better speed tracking performance.