Research On PMSM Servo System Based On DSP

This thesis took permanent magnet synchronous motor as the research object, and established the mathematical model of BLDCM, on the basis of which, its control technology got a in-depth study. At the same time, based on the coordinate transformation theory, the mathematical model of PMSM was established, where vector control problem based on SVPWM technology was discussed. Meanwhile, this thesis designed and optimized the closed-loop control system of current and velocity of of permanent magnet synchronous motor based on TMS320F2808 controller, whose control performance would be verified through simulation and experiment.Firstly, this thesis established the mathematical model of BLDCM and discussed the control method of BLDCM. On this basis, some software module of the driver were emphatically discussed, involving current sampling process,motor starting and commutation control, Hall commutation, low-speed ripple restrain and RS232 communication. When designing the control algorithm, in order to decrease the overshoot and saturation, the thesis introduced ameliorated integral anti-windup into PID algorithm, and tuned the parameters based on velocity error. Then, this thesis elaborated the control strategy of PMSM and emphatically analyzed the principle of vector control and SVPWM technology, which based on a mathematical model of the PMSM. The implementation issues of vector control was analyzed and discussed on the basis of the Dual-loop control system simulation model of vector control based on SVPWM technology in MATLAB/simulink environment. Finally, this thesis designed DSP embedded control system on the basis of the foregoing theoretical analysis, mainly include the hardware parts, such as DSP peripheral circuit, encoder module, Hall module and three-phase inverter modules, etc and software part, such as AD sampling, interrupt control, speed calculation, SPWM waveform generation module and fault protection module. At the same time, the system can communicate with the host computer through 232 serial port, which can be used to complete setting work mode of the drive, debugging PID parameters and real-time monitoring the drive running state. Experimental results shows that the system has reached a good tracking performance and static performance.This thesis studied the principle and design method of sliding mode variable structure control, then analyzed and discussed its application in BLDCM servo system, after which the simulation model in MATLAB/simulink environment was established. Simulation results shows that compared with the traditional PID control, SMC has obvious advantages in the anti-interference performance.