Research On Magnetic Coupling Resonant Wireless Charging System For New Energy Vehicles

Due to the low cost and poor versatility of charging pile contact charging,in this paper,a new energy vehicle wireless charging system based on the principle of magnetic resonance coupling is proposed and designed.The main research contents are as follows:Firstly,the coupling resonance of two coils of SS structure is analyzed by means of equivalent circuit theory.In order to reduce the influence of the load impedance on the noncontact charging characteristics,the four coil coupled resonant design scheme is proposed and analyzed.The change of coil diameter and the number of turns of wire is simulated by Matlab and Air-Cored Coil Calculator,which provides the basis for designing high quality factor coil.Secondly,the overall working block diagram and charging flow chart of the system are constructed.Hardware design includes rectifier filter,DC voltage regulation and high frequency inverter circuit,the function and selection of hardware circuit are introduced,both the transmitter and the receiver of the rectifier filter circuit are controlled by bridge rectifier,the full bridge inverter mode is adopted in the high frequency inverter circuit of transmitter.Thirdly,the control circuit of the power transmitter and receiver is designed,the function of each link of control circuit and the selection of the components are discussed.The transmitter control circuit based on the phase locked loop can adjust the turn-on of the MOS circuit of the high frequency inverter circuit,realization of high frequency inverter output frequency automatic tracking of coil resonance frequency.The receiver control circuit dynamically adjusts the IGBT duty cycle through the BP neural network algorithm and the classical PI algorithm,to achieve maximum output power by adjusting voltage.Finally,four coil coupling resonance model was established by ANSYS Maxwell,equivalent circuit simulation analysis of four coil coupling using ANSYS Simplorer.The changes of wireless charging distance,excitation source frequency,wire diameter and coil diameter are simulated respectively,the influence of the above factors on the non-contact charging efficiency and power is analyzed.