Design And Analysis Of Wheel Multi-disc Coreless Permanent Magnet Synchronous Motor For Vehicle

With the depletion of petroleum fuel and the aggravation of vehicle emission pollution in the world,the major automobile enterprises begin to develop green new energy vehicles instead of traditional fuel vehicles.As a clean,green and sustainable energy,electric energy is bound to become one of the main energy sources for the development of new energy vehicles in the future.Electric vehicles are more and more accepted by automobile enterprises and consumers.For domestic and foreign researchers,they pay more attention to the motor as the direct driving source of electric vehicles.At present,most of the electric vehicles in the market use the traditional radial flux motor as the central centralized drive motor,which has the disadvantages of low power density,large volume and so on.In addition,it also has the problems of low transmission efficiency,complex structure and so on.Direct drive wheel drive electric vehicle is to assemble the driving motor and tire,so that the driving force generated by the motor is directly transmitted to the driving wheel,and there is no energy loss in the middle.In addition,each driving wheel can be controlled by the electronic control unit,so that the electric vehicle has a variety of driving modes,and improves the mobility of the electric vehicle.This direct drive hub drive is bound to become the main driving form of the electric vehicle in the future.Disc permanent magnet synchronous motor is especially suitable for the situation of limited installation space in the hub motor,because it has the advantages of high torque density,compact structure,axial size and so on,in this paper,a new type of hub motor is designed for urban micro electric vehicle.Based on the multi disc structure,a permanent magnet synchronous motor structure composed of three rotor discs and two coreless stator armatures is proposed.The electromagnetic simulation analysis and vector control system are carried out.Finally,the vehicle performance is simulated and analyzed.First of all,the driving force and resistance of the electric vehicle are analyzed in detail,and the advantages and disadvantages of the current two driving types of hub motor are analyzed.At the same time,the basic electromagnetic relationship of disc Coreless Permanent magnet motor is analyzed.Based on the multi disk topology,the three-rotor double stator Coreless Permanent magnet synchronous motor is selected as the direct drive hub motor.Then,the three-dimensional simulation model of the motor is established in ANSYS Maxwell software,and according to the simulation results,the parameters of the motor structure are optimized in Maxwell,so as to improve the air gap magnetic field of the motor.The parameters of the permanent magnet structure of the two outer rotors,the thickness of the rotor yoke and the pole arc coefficient of the permanent magnet of the middle rotor are optimized,so as to obtain the best structural parameters.At last,according to the mathematical model of the electric vehicle,the output of the electric vehicle is optimized in the low-speed driving mode the four-wheel drive control module of electric vehicle is built.The dynamic performance and driving range of the electric vehicle equipped with the multi disc Coreless Permanent magnet synchronous wheel motor designed in this paper are simulated and estimated,and the wheel motor designed in this paper is further verified.