Research Of Vector Control System For Permanent Magnet Synchronous Motor

With the significant advantages of simple structure, small moment of inertia, high efficiency, permanent magnet synchronous motor (PMSM) has taken a very important place of AC speed control system. Digital PMSM control system based on digital signal processor is easy to achieve high performance algorithm and different kind of intelligent control. Because of this advantage make it become the development trend of AC speed control system.At first, present situation and development trend of PMSM speed control system is introduced, mathematical model of PMSM in different coordinate system is built, and vector control theory based on PMSM mathematical model is also introduced in this dissertation. Appropriate current control mode is chosen to build control system. Than the simulation model of PMSM control system based on the theoretical analysis is built with simulation software.Secondly, the hardware system of PMSM vector control system is built. Hardware includes PMSM, main control board, and main power circuit.Software system is built based on the building of hardware system. Software main includes interrupt service subroutine, the initial rotor position program, rotor position calculation program, and SVPWM modulation program.Based on the hardware and software designed, the control system is debugged. The speed waveform and current waveform during the debug is given in this dissertation. The system’s steady-state and dynamic characteristics is tested.Finally, high frequency voltage signal injection method is selected to detect initial rotor position, by this way to improve control system’s startup characteristics. Based on the theoretical analysis, the simulation model of high frequency voltage signal injection method is built with simulation software to prove feasibility.