High-precision Permanent Magnet Synchronous Servo System

The benchmark rev source equipment is designed to provide rotational speed reference for calibrating aerial tachogenerator and tachometer. High velocity precision, wide speed range and stepless speed adjustment are features of the system.The hardware platform of AC frequency-control system is based on TMS320F240 DSP controller and uses IPM (Intelligent Power Model) as power device, uses Square-wave Rare Earth Permanent Magnet Synchronous Motor as actuating mechanism. The software is mainly programmed by C-Language, and partly by built-in Assembler-Language.The voltage converter works in PWM mode. Frequency-control speed regulation, DC voltage supply monitoring of the converter, synchronous motor power-angle close-loop control are combined. When motor running, rotor real-time position-signal is captured, and compared with stator voltage wave to calculate motor power-angle, which is the base of close-loop voltage PWM regulation. Motor running high-precisely and avoiding loss of synchronism are both realized. Working current of the motor is lowered down, and efficiency increases.This dissertation studies synchronous motor frequency-control speed regulation, the power-angle characteristics of Rare Earth Permanent Magnet Synchronous Motor and the software realization of high precise speed control. The improvement of IPM control circuit and protection circuit is also presented in the paper. It has been proved by experiments that the scheme of system is rational, the method of detection and control is feasible, and this system realizes high precise, wide-range, stepless and bidirectional speed control, prevents synchronous motor from loss of synchronism. The index of performance reaches or beyonds design requirements.