Design Of Permanent Magnet Synchronous Motor Control System Based On FPG

Permanent magnet synchronous motors are widely used in industrial manufacturing,new energy vehicles,and household appliances due to their small size,simple structure,and high power density.In permanent magnet synchronous motor vector control systems,PI control is commonly used to achieve dual closed-loop control of the speed loop and the current loop.By selecting appropriate PI parameters,the control system can achieve fast and static error free speed regulation.However,with the expansion of the application field of permanent magnet synchronous motors,traditional PI control is difficult to meet the control needs in complex and volatile working environments.In recent years,the control algorithms of permanent magnet synchronous motors have developed rapidly.The emergence of new algorithms has improved the performance of the system,but also has higher requirements for the chips used in the control system.FPGA has fast computing speed,flexible interfaces,and repeatable programming,meeting the requirements of complex algorithms for control chips.With the decrease of FPGA price and the improvement of its performance,FPGA has been widely used in the field of motor control.Therefore,using FPGA to implement new control algorithms is conducive to the development of permanent magnet synchronous motor control systems.Firstly,by analyzing the characteristics of various nonlinear control methods,this paper selects sliding mode control and deadbeat predictive current control to replace the PI control used in the speed loop and current loop of traditional vector control,respectively.Considering that complex mathematical functions are not easily implemented in FPGA,the approach rate method is chosen as the improvement direction of sliding mode controller.Based on the analysis of the principle of sliding mode control,a speed loop controller is designed to improve the exponential approach rate in the traditional approach rate method.A deadbeat predictive current control algorithm is derived to design a current loop controller.Select MATLAB/Simulink as the simulation platform to model the control system and analyze the simulation results.Then,the HDL code generation method based on the Simulink model is used to generate code for the designed system.This method can accelerate the development efficiency of FPGA,but it has certain requirements for the model.Therefore,modify the system model before code generation.The modification includes two aspects: one is to make the model conform to the HDL code generation requirements in Simulink,and the other is to simplify the model to reduce the computational complexity of FPGA.The design principles of the redesigned carrier generation module,pulse width modulation module,and derivative function module are described in detail.Through simulation,the speed response of the modified system model is compared with that of the unmodified system model,and the results show that the modified model retains the speed regulation performance of the original system model.On this basis,the modified model is fixedly processed and the steps to generate HDL code using the "HDL Workflow Advisor" function are introduced.Finally,a hardware experimental platform was built to conduct a no-load motor experiment at a given rotational speed,and the experimental results were analyzed.The results showed that the permanent magnet synchronous motor control system designed had some shortcomings but could complete the basic speed regulation function,verifying the feasibility of the designed system.