Research On Doubly-fed Linear Drive Motor For High-speed Rail Transit

At present,with the continuous expansion of urban and rural areas,the rural revitalization plan is also in full swing,and the demand for transportation between cities and between urban and rural areas is surging.Doubly fed linear motor(DFLM)develops the traditional rotating doubly fed motor into linear motor like linear induction motor and linear synchronous motor.The control of doubly fed motor has been very mature in the field of wind power.The superior electrical control performance of doubly fed motor can be applied to the field of linear drive after reasonable transplantation.The research on DFLM is in the experimental stage at home and abroad.The new traction motor provides help for the development of diversified rail transit.This paper has analyzed the motor circuit model and electromagnetic field model.According to the motor design experience,the preliminary modeling and analysis of highspeed doubly fed linear motor are carried out,and the difficulties in the design of high-speed linear motor are discussed.In order to meet the requirements of rail transit traction system,the winding structure and cogging structure of the motor are optimized by unequal pole distance and other methods,and verified by finite element simulation.Referring to the basic resistance and traction characteristics of existing high-speed wheel rail transit vehicles,this paper further studies the traction characteristics of long stator doubly fed linear motor as traction motor of rail transit train.This paper focuses on the analysis of the change of the basic resistance model of the train caused by the normal force due to the doubly fed linear motor’s normal force,.Finally,the traction condition of the long stator doubly fed linear motor is theoretically predicted and calculated,and the acceleration and speed curve of the train driven by the doubly fed linear motor is calculated,which is compared with the traditional rotating motor traction.Aiming at the long stator doubly fed linear motor,this paper takes the existing long stator motor power supply system as a reference,analyzes and calculates the voltage and current of the long stator when the output voltage of the inverter is fixed from the structure of the long stator,designs the traction power supply scheme suitable for the motor,and calculates the inverter capacity combined with the typical calculation examples in this paper.