Topology And Characteristic Analysis Of Primary Vernier Permanent Magnet Linear Motor

With the rapid development of social economy and the expansion of contemporary cities,the pressure of ground transportation is gradually increasing.The driving device in the field of green,intelligent and comfortable long-distance rail transit has become a hot topic.The primary permanent magnet linear motor has the advantages of low speed,large thrust,small turning radius,rapid dynamic response,small tunnel section,and so on,which breaks out the tight encirclement from the linear motor and provides a new idea for the drive system of modern urban rail transit.Aiming at the technical requirements of the drive motor in the long-distance rail transit,in order to further improve the operation performance of the primary vernier permanent magnet linear motor,taking the air gap magnetic density of the motor as the starting point,this thesis carried out research on three new types of primary vernier permanent magnet linear motor(PVPMLM).The main research contents are as follows:First of all,the thesis analyzes the development history and research status of primary permanent magnet linear motor at home and abroad.Through the mutual promotion and structural evolution of permanent magnet rotary motor and permanent magnet linear motor,it highlights the advantages of primary permanent magnet linear motor applied to rail transit drive system.Secondly,taking the magnetic circuit and magnetic field distribution of the motor as the starting point,based on the finite element analysis method,the electromagnetic properties of the primary permanent magnet linear motor,such as permanent magnet magnetomotive force,magnetic conductivity,no-load air gap magnetic density,back electromotive force and thrust,are comprehensively analyzed,providing a basis for the further optimization of the motor.Thirdly,in order to further solve the problem of magnetic flux leakage between the poles of the permanent magnet and the unadjustable thrust of the motor,and to greatly improve the electromagnetic performance of the motor,on the basis of the magnetic field modulation theory,three different new topological structures are proposed,namely,the new magnetic barrier coupling primary vernier permanent magnet linear motor,the hybrid excitation primary vernier permanent magnet linear motor,and the hybrid excitation primary vernier permanent magnet linear motor,With the help of finite element method,their respective structural advantages are analyzed.Finally,the structural parameter optimization and electromagnetic characteristics of three new topology motors are compared and analyzed.The research results show that the primary vernier permanent magnet linear motor has the characteristics of simple structure,high thrust density and high fault tolerance.In the alternating pole structure,the motor has low thrust fluctuation;In the magnetic barrier coupling secondary,it is necessary to pay attention to the secondary saturation of the motor.Adding a suitable magnetic barrier to the secondary will improve the electromagnetic performance of the motor;In the hybrid excitation structure,the motor has high thrust regulation performance.The research in this thesis provides a research basis for the further theoretical analysis and application of the primary permanent magnet linear motor.