Research On Servo Control System Of Multi-axis Permanent Magnet Synchronous Motor Based On FPGA

Mechanical phased array antenna adopts sPIral antenna as radiation unit,and the scanning control of microwave beam needs to be realized by mechanically rotating sPIral antenna to reach predetermined radiation phase.The sPIral antenna unit is connected to the motor and other driving devices,and the motor rotates to drive the antenna unit to rotate,so as to realize the phase control of the radiating unit.Therefore,the motor servo control system used to drive the motor rotation is an important part of the phased array antenna.Permanent magnet synchronous motor has the advantages of high power density,small size,high efficiency,low inertia,fast response,etc.,the use of permanent magnet synchronous motor to drive the sPIral antenna rotation can achieve raPId and accurate unit phase control.The traditional permanent magnet synchronous motor servo control system adopts three closed-loop control strategy,and the current loop is its innermost loop.Its dynamic response and steady-state response capability directly affect the performance of the whole servo control system.In order to improve the performance of current loop and realize the parallel control of multi-axis motor,this paper studies a vector control scheme based on current prediction control and realizes the multi-axis servo control system based on FPGA.This paper firstly introduces the research significance of permanent magnet synchronous motor servo control system,and investigates the research status at home and abroad.Secondly,according to the working principle of permanent magnet synchronous motor,the mathematical model of permanent magnet synchronous motor and the traditional vector control algorithm are briefly described,and the control strategy of id=0 is determined.In order to improve the frequency response of the current loop,a predictive current control algorithm for permanent magnet synchronous motor is introduced.In order to verify the effectiveness of the theoretical analysis,a double closed-loop permanent magnet synchronous motor servo control system was built based on MATLAB/Simulink platform.The traditional vector control was adopted in the overall structure,in which the current loop replaced the original PI controller with the deadbeat predictive controller.In the simulation results,compared with the PI controller,On the current closed loop: the q-axis dynamic response of the deadbeat current prediction controller is significantly improved,the q-axis steady-state error is reduced by 5.4%.In the speed closed-loop,the steady-state error is only 1/5 of that of the PI controller when the speed rise time is reduced.Simulation results show that compared with the traditional vector control,the frequency response of the current loop can be improved by introducing the deadbeat current prediction control.The control IP core of permanent magnet synchronous motor is constructed,and the speed PI control module,current prediction control module,coordinate transformation module,SVPWM module,SPI module,QEP module and Cordic module required in the control algorithm are designed and simulated respectively.At the same time,2 axis(multi axis)SoPC servo control system is set up.Finally,the control performance of the designed fpga-based multi-axis permanent magnet synchronous motor servo control system was verified by experiments,including preparation experiment,single-axis current closed-loop experiment,single-axis speed closed-loop experiment and multi-axis linkage experiment.Uniaxial test shows that the servo control system designed in this paper realizes the closed-loop control of speed loop and current loop at high control frequency.The dynamic response time of the current closed-loop is 7-8 control cycles,and the steady-state error is about 0.2A.When the motor rotates at a constant speed of 600r/min,1200r/min and 1800r/min,the rising time of the speed closed loop is 10 ms,17ms and 22.5ms,and the steady-state error is about 1%,0.91% and 0.25% respectively.The whole system can in real time according to need all the parameters in the configuration register,in multi-axis test show that the shaft can receive independently Nios ? controller control instruction,parallel complete the required function.