Research On Permanent Magnet Synchronous Vector Control System Based On FPGA

In recent years,permanent magnet synchronous motor(PMSM)has been applied in all kinds of industry.The traditional vector control system of permanent magnet synchronous motor(PMSM)uses DSP as the controller.However,the current loop designed based on DSP has the problems of small current loop bandwidth and slow response speed.In recent years,the design of DSP + FPGA appears gradually,in which the current loop is implemented based on FPGA to improve the bandwidth of current loop,while the speed loop is still controlled by DSP.However,such a design not only needs the design of high-speed communication data exchange between DSP and FPGA,but also wastes some resources.The interface of FPGA is flexible and the modular design is simple.So it can completely replace the controller in traditional vector control system.Therefore,the research of PMSM vector control system based on FPGA has become a hot spot in PMSM research.Based on the analysis of the mathematical model of PMSM,a sliding mode observer based on extended back EMF is established and the scheme of PMSM control system without position sensor is designed.Compared with traditional DSP as controller and considering the advantages of FPGA in timing control and algorithm acceleration,a sliding mode observer based on repeated sampling is designed which not only give full play to the hardware condition of FPGA,but also reduce the chattering of the system,and improve the observation accuracy of rotor speed and position.Based on FPGA,speed vector control system and sensorless control system of PMSM are studied.The design flow of FPGA is introduced in detail,and several important modules like SVPWM module,coridc algorithm module,AD sampling module are explained from principle to simulation in detail by using the top-down design scheme.According to the module delay,not only the current loop bandwidth is calculated in detail,but also the starting sequence of the sliding mode observer is divided.Finally,on the basis of the report,the resource utilization of the whole sensorless control system is analyzed.The hardware platform of PMSM control system is built.Based on the selection and analysis of FPGA,ad interface conversion circuit,encoder signal processing circuit and over-current protection circuit are designed.The no-load experiment of PMSM with speed vector control system is carried out and the correctness and feasibility of the system are partly verified.