Research On The Magnetic Coupling Mechanism Coil Type And Compensation Network Topology Interoperability Of Wireless Charging System For Electric Vehicle

Wireless charging technology,as a new type of charging method for new energy vehicles,has the advantages of safety,reliability and high flexibility.It has been widely concerned by domestic and foreign research institutions and scholars.Judging from the development of the industry,China’s electric vehicle wireless charging technology will enter the stage of large-scale promotion in the next few years.However,the wireless charging system itself has many branches of technical routes.In the large-scale application stage after the multi-model and multi-equipment manufacturers put into operation,if the wireless charging systems of different modules/parameters/topologies cannot meet the interoperability requirements,on the one hand may cause waste of power resources,on the other hand,it will cause certain security risks.Therefore,ensuring the interoperability of the charging system is one of the key factors for the growth of the industry.This thesis studies the interoperability of the magnetic coupling mechanism coil type and compensation network topology of electric vehicle wireless charging system.Firstly,the structure of the magnetic resonance WPT system and the power transmission process are analyzed.Then,the mutual inductance equivalent models of typical and compound topologies were established,the axial distance and offset characteristics of the coils were analyzed,and the interoperability of coil types and compensation network topologies were simulated by Maxwell and Matlab respectively,and the interoperability of various types of coils and topologies were evaluated.The main research work of this thesis is as follows:(1)The coupled model and the mutual inductance equivalent are used to analyze the theoretical model of the coupling mechanism.Finally,the typical and composite topological models are built according to the mutual inductance equivalent,and the axial distance and offset characteristics of magnetic coupling coil are analyzed based on frequency splitting phenomenon.(2)Through the three-dimensional Maxwell transient magnetic field of the coil in the magnetic field distribution in the process of transmission system for analysis,and set the axial distance and radial offset distance of the primary and secondary coils as variable parameters,study the influence on the transmission characteristics of the system,the Simulink simulation circuit was designed to simulate the intercommunication of the compensation network topology,the power variation amplitude and constant voltage or constant current output characteristics of each topology system were analyzed.(3)Calculate the coil structure and compensation network device parameters according to the coil self-inductance,wind the coil and build the compensation network and prototype platform,and conduct experimental verification on the simulation results of interoperability.By comparing the simulation and experimental results,it can be found that the circle is the coil type with the strongest interoperability of the primary and secondary sides,and the s-type and p-type are the topological types with the strongest interoperability in the primary and secondary side compensation network,respectively.The research results in this thesis can be used as a reference for the production of interoperable test gauge equipment and wireless charging products,and provide experience for the interoperability research of wireless charging systems for electric vehicle.