Research And Design Of Permanent Magnet Synchronous Motor Servo Control

Permanent magnet synchronous motor is widely used in industrial equipment.Its control accuracy,speed regulation range and response speed have an important impact on the performance of industrial equipment.Aiming at the customized demand of motor control for four-wheel omni-directional all drive mobile robot,this paper carries out the research on the key technology of permanent magnet synchronous motor servo control and the prototype design of servo controller principle.Based on the mathematical model of permanent magnet synchronous motor and the principle of field oriented control,the voltage space vector pulse width modulation technology and three closed-loop control technology are deeply studied.According to the mathematical model of permanent magnet synchronous motor,the recursive least square method is used to identify the stator inductance and winding resistance parameters of permanent magnet synchronous motor,and then the PI control parameters of current loop and speed loop are obtained.The SIMULINK simulation platform of permanent magnet synchronous motor servo control is built,and the simulation verification of control parameters is completed.Based on voltage space vector pulse width modulation and three closed-loop control technology,the hardware and software design of servo controller are completed.The hardware design adopts the combination of ARM and FPGA,mainly including three-phase inverter,IGBT isolation drive,stator winding current isolation sampling,bus voltage isolation sampling,encoder sampling,over-current temperature protection and other circuits.The upper IGBT driving circuit adopts charge pump design,which does not need special drive chip and improves reliability.The software design is divided into MCU and FPGA.The FPGA part mainly includes the design of dual port RAM,stator winding current acquisition and filtering,control pulse output,control protection and so on,which can interact with MCU through 16 bit parallel port;MCU mainly realizes encoder sampling and solution,bus voltage acquisition,CLARK transformation,PARK transformation and inverse transformation,voltage vector synthesis,current loop control,speed loop control,zeroing control,communication and other functions.Voltage vector synthesis adopts seven section design,which supports the shortest control cycle of 100 us and the highest speed of 1500 rpm.Zeroing control adopts open-loop design,and the communication interface supports Modbus protocol.In this paper,the permanent magnet synchronous motor servo control experimental platform is built by using the magnetic particle brake.The motor start / stop and forward /reverse experiments are carried out under no-load and load conditions respectively.The software and hardware design,control parameters and control functions are verified,which lays a foundation for the distributed control of omni-directional and all drive mobile robot without independent motion controller.