Research On Wireless Recharging System Of Electric Vehicle

Electric vehicle wireless charging technology can effectively reduce the number of batteries carried by electric vehicles,reduce the manufacturing cost of electric vehicles,and increase the mileage of electric vehicles.At the same time provide more convenient and convenient charging method.The application prospect is broader,with great research significance and practical value.This article introduced the electric energy transmission technology of electric car,and expounded the research status of magnetic coupled resonant wireless energy transmission technology(MCR-WPT)at home and abroad.The basic principle of MCR-WPT and the range of electromagnetic field are analyzed.The transmission system is modeled by circuit theory and coupled-mode theory.The transmission power and efficiency formulas of the system are deduced,and the impedance and frequency characteristics of transmission are analyzed.Influencing,for the coupling characteristics of the system,the numerical simulation of the size,parameters and transmission distance of the coil is given by establishing the mutual inductance model of the transmission coil.The parameters of the coil have a direct influence on the coupling effect.The parameters design of the coil should fully consider the requirement of the transmission distance.The small-sized coil is more effective at close distances,while the long-distance transmission needs to increase the size of the coil.The ANSYS finite element calculation simulation software is used to further study the resonant circuit,and the transmission characteristics under different circuit parameters and the magnetic circuit conditions under different coil positions are simulated and analyzed.Simulation analysis shows that the axial and radial displacement of the coil will affect the coupling between the two coils,and the use of ferromagnetic materials can improve the magnetic field distribution and coupling between the coils.Based on the research results,the wireless charging device for electric vehicles is designed.Circuit design,device selection and drive programming are performed for each module of the hardware circuit.Finally,wireless charging devices for electric vehicles with different power levels are developed.The effects of the transmission frequency,resonance state,and coupling mechanisms on the transmission system were analyzed experimentally.The optimized coupling mechanism not only improved thetransmission efficiency of the system,but also the allowable variation range of the transmission and receiving coil offset and transmission direction was improved.