Research On Control Strategy Of Direct-drive Automatic Gate Based On STM32

Permanent magnet synchronous linear motor(PMLSM)is widely used in industrial control because of its high power density and low power consumption.PMLSM is also used as the driving motor for direct drive automatic door.PMLSM vector control system is designed based on the research background of direct-drive automatic door.Aiming at how to enhance the robustness of direct-drive automatic door control system,this paper makes a thorough study from the aspects of mathematical model,simulation and experiment.Based on the mathematical model of PMLSM,a current-speed vector control double closed-loop control system is built.In order to improve the speed following performance of the direct-drive automatic gate,a speed controller based on predictive function control(PFC)is proposed.Aiming at the problem of parameter error and load disturbance in the process of establishing PMLSM.An extended state observer(ESO)is designed and applied to feedback compensation of current loop to improve the anti-disturbance ability of the system.Based on PFC+ESO current-speed closed-loop system,a direct-drive automatic gate current-speedposition three-closed-loop system is established to realize the fast tracking and precise positioning function of the direct-drive automatic gate.Firstly,according to the basic structure and operation mechanism of direct-drive automatic door,the mathematical model of PMLSM vector control is established.The current-speed closed-loop system and current-speed-position closed-loop system of PMLSM are built by traditional PI controller,and the Simulink simulation experiment is carried out.Secondly,based on PMLSM vector control mathematical model,in order to improve PMLSM speed following performance,a current-speed control method based on PFC speed controller and PI current controller is proposed.At the same time,in order to enhance the anti-interference ability of the system,a control method using ESO observation system disturbance and feedback to the current loop is proposed.Simulink simulation model of PFC+ESO current-speed control method is built,and compared with traditional PI controller,the effectiveness and reliability of the proposed method are verified.Finally,the hardware and software platform based on STM32 control system is established.The hardware circuit mainly includes control circuit,drive circuit,current sampling circuit,external AD7606 conversion circuit,position sensor,etc.The software system mainly realizes the PMLSM control system based on keil 5.0,including the main interrupt PWM update program,AD conversion interrupt program and function module.Compared with the traditional PI speed controller,the PFC+ESO speed controller has better speed following performance and anti-jamming ability.In the current-speed-position closed-loop experiment of PMLSM,the PFC+ESO speed controller has faster speed following performance than the traditional PI control method.