Research Of Permanent Magnet Synchronous Motor Vector Control System

the rotor position and speed detection is very important in the permanent magnet synchronous motor control system. Therefore, how to get rotor’s position and speed information is an important aspect. Direct measurement of rotor position sensor will increase system cost, at the same time, the requirement of motor working environment is much stricter. So, PMSM sensorless control system reaching becomes especially necessary. In this article, the permanent magnet synchronous motor vector control system based on sliding mode variable structure observer is researched.In the paper, the general coordinate transformation and the mathematical model of PMSM and vector control principle are all introduced. Correspondingly, a control system simulation model using Matlab/Simulink is set up, in the study of the principle of the PMSM sliding mode variable structure observer, the following issues are raised: First, for the arctangent of the ratio of the back-EMF appears infinite; Secondly, the speed observed exist jitter; finally, the amplitude reduced by the low-pass filter caused the speed estimation error. So, some improvement measures aim to resolve these problems is proposed, includes rotor position points sector calculation, with two filters to eliminate jitter, to the rotor position indirect derivation for speed. Then, the improved sliding mode variable structure observer model is established based on Matlab/Simulink platform, simulation and comparison results show that the improved sliding-mode observer has obvious eliminate jitter function for observed rotor speed and accurate rotor position observation ability. Finally, according to the requirements of the whole control system and experimental conditions, the PMSM vector control system platform is designed, experimental results proved that the experimental platform is correctness and reliability.