Sensorless Vector Control System Study Of Permanent Magnet Synchronous Motor Used In Electric Vehicle

In order to alleviate the oil shortage and environmental pollution caused by fuel vehicles,electric vehicles have been greatly promoted.Interior Permanent Magnet Synchronous Motor(IPMSM)is widely used in traction system of electric vehicle because of its excellent performance.However,rotor position information and speed information are required when vector control is applied to the IPMSM.The traditional way is to use mechanical sensors to detect such information,which not only increases the production cost of electric vehicles,but also reduces the reliability of the system.In view of this disadvantage,the mechanical sensor is discarded and the rotor position & velocity are estimated by other methods in this paper.A sensorless control scheme is designed to realize the stable operation of IPMSM at full speed range,and the feasibility of the proposed scheme is verified by MATLAB simulation.The main research contents are as follows:1.Firstly,the IPMSM vector control system with sensors is studied.The mathematical model of IPMSM is deduced,the principle and system composition of vector control are analyzed,and the control parameters of each part are calculated.IPMSM vector control scheme with sensor is designed.2.The rotor position and velocity identification of sensorless IPMSM at high speed are investigated by model reference adaptive method.A high-speed identification system based on this method is designed and simulated by MATLAB.3.The rotor position and velocity identification of sensorless IPMSM at low speed are investigated by high frequency signal injection method.A low-speed identification system based on this method is designed and simulated by MATLAB.4.With the combination of high frequency signal injection and model reference adaptive control,a sensorless IPMSM rotor position and speed identification system at full speed range is designed.The results show that the "high frequency signal injection + model reference adaptive" control scheme based on variable weight switching mode can achieve stable operation in sensorless IPMSM vector control system at full speed range.