Research On Position Sensorless Technology Of Surface Mounted Permanent Magnet Synchronous Motor

Permanent magnet synchronous motor(PMSM)drive system is widely used in industrial control and daily life.In the control system of PMSM,it is necessary to obtain accurate rotor position and rotational speed information,which is usually obtained by the external hardware position sensor.In order to solve the problem caused by hardware position sensor and improve the reliability of drive system,sensorless technology has gradually become a research hotspot in the field of motor control.Firstly,the status of PMSM sensorless technology is reviewed.This paper mainly studies the sensorless control technology of surface mounted PMSM under zero speed and low speed operation.Secondly,the mathematic model and vector control strategy of surface mounted PMSM are analyzed,and the validity of vector control strategy of surface mounted PMSM with position sensor is verified by simulation.On this basis,the high-frequency mathematic model of surface mounted PMSM is analyzed,and the basic working principle of traditional high frequency injection(HFI)method and its defects are analyzed.Furthermore,an improved high frequency square wave voltage injection method is proposed to improve the problems of large amount of computation and phase delay caused by many digital filters in the traditional HFI method.Then,a simulation model is built in the MATlab/Simulink simulation environment to explore the problem of phase delay in the traditional HFI method,and verify the effectiveness of the high-frequency square wave voltage injection method to improve the traditional high-frequency signal injection method.Finally,the hardware and software of sensorless control system of PMSM are designed with TMS320F28035 as the main control state chip.Figure [56] table [3] reference [80]...