Design And Implementation Of AC Servo Motor’s Control Device Based On DsPIC

Together with the rapid development of power electronics, microelectronics, new motor control theory and rare earth permanent-magnet material in recent years, permanent magnet synchronous motor(PMSM) obtained the rapid popularization and application. Permanent magnet synchronous motor has the advantage of small volume, low loss, high efficiency and so on. Energy saving and environmental protection is emphasized day by day, so it is very important to study on it.First of all, this paper presented the AC servo system’s structure composition and control mode. Studying on Space Vector Pulse Width Modulation(SVPWM) modu-lation strategy under the60°coordinate system according to permanent magnet synchronous machine, this strategy reduced the complexity of operation process. In addition, traditional two-level inverter is upgraded to three-level inverter, traditional PI control algorithm is upgraded to sliding mode variable structure control algorithm. Launching the work from hardware aspect and software aspect in this article:In hardware aspect, taking the dsPIC30F4011chip which is produced by Microchip corporation as the main control chip of this system. According to main control chip’s characters, designing simulation given unit, orthogonal encoder unit, current feedback unit, fault treatment unit and so on. Control circuit outputs the Pulse Width Modulation(PWM) signal to control three-level inverter’s switch motion, thus the driving process of permanent magnet synchronous motor is realized. In software aspect, using Matlab/Simulink to complete AC servo system’s simulation, the sliding mode variable structure control algorithm in position loop and speed loop and SVPWM modulation strategy under the60°coordinate system to control inverter. Then the AC servo system is divided into different functional modules. Definiting various modules’relationships, the flowchart of the main program and interrupt subprogram are designed. Compiling C code in MPLAB development environment and downloading it into main control chip. Finally the synthetic debugging is proceeded according to the system’s software and hardware. The experimental result indicated that this control device has stable performance, reliable operation and practical value.