Optimal Design Of Wireless Power Transfer System Via Magnetic Resonances Coupling

The convenience and necessity of wireless energy transfer technology has become more and more prominent in the continuous development of society.The wireless energy transfer technology mainly includes inductive coupling,radiation,electric coupling or magnetic resonance coupling.Among them,the wireless power transfer system via magnetic resonance coupling integrates electromagnetic technology,power electronics technology,and modern control theory.It has obtained a wide range of application scenarios due to the characteristics of long transmission distance and large power.In this paper,the magnetic resonance coupling structure and the transmission system circuit are modeled and analyzed,and the inductive-current design method and the turns-power design method are proposed for the optimal design of the system coil through formula calculation.In order to increase the transmission distance of electric energy,a one-by-one variable design method is proposed for the double relay coil.These design analyses provide methods for subsequent system analysis and system simulation and experimentation.Secondly,on the basis of formula derivation and calculation,the software is used to digitally analyze the influence of system influence factors on transmission characteristics,and the coil characteristics,load characteristics,and frequency characteristics of the system are described.Using Matlab combined with the proposed system design method,the parameters such as coil turns and transmission distance are optimized to improve the transmission efficiency,power and stability of the system;in order to facilitate tuning in practice,an LCCL transmitter circuit based on an equal current small capacitor array is proposed.According to the optimized parameters,Simulink simulation is performed on the high-power transmission system and the longdistance transmission system to verify the correctness of the parameter selection.Finally,the circuit hardware required for the experiment was selected,and the main circuit and control circuit of the system were developed.The experiment of the high-power transfer system and the long-distance double-relay coil transfer system was completed.It successfully transmitted more than 2k W outside 28 cm,and successfully use the relay coil 1.8m away to achieve efficient transmission of energy with an efficiency exceeding 80%.The correctness of the proposed wireless energy transfer via magnetic resonance coupling design method is proved.