Research On The Control System Of Low Speed And High Torque Permanent Magnet Synchronous Motors

The characteristics of the low speed and high torque permanent magnet synchronous motor (PMSM) system are high control precision and output torque. It's widely used in high-speed elevators and conveyor control systems. Research on proposing system performance optimization of the low speed and high torque PMSM control system is of great significance to promote its development in the industry.Based on the analysis of PMSM control system of status and trends, the thesis presents the applicable control strategy, system software programming, control precision optimization programs and system efficiency improving programs. The simulation and experiment show that the optimization programs could improve the control performance of the system.Firstly, the thesis analyzes vector control and SVPWM technique, and focuses on the basic principle of coordinate transformation and realization of SVPWM from the motor mathematical model. The strategy id=0 and PI control is applied in the current regulator.Secondly, by MATLAB/SIMULINK, this thesis builds SVPWM module and coordinate transformation module; it establishes the PMSM vector control system simulation model and tests in load and speed. The simulation shows that control system is accurate and workable.Thirdly, the master control program and the PWM interrupt routine, the SVPWM and coordinate transformation program modules are written and verified. SVPWM and the rotor position and speed detection function are achieved in the software.Finally, for improving the speed accuracy and motor efficiency, the mathematical methods of resolver/digital converter resolution are given and validated. Based on the mathematical model of permanent magnet motor, the relation between the motor loss and the id is acquired. The system efficiency improving control strategy is verified in the simulation...