Design And Development Of Magnetically-Coupled Resonance Wireless Power Transfer Systems

The Magnetically-Coupled Resonance Wireless Power Transfer(MCR-WPT)has become the mainstream wireless energy transmission technology.This paper presents a comprehensive study on the magnetically coupled wireless power transmission theory,the design and optimization of power amplifiers and resonant coils,as well as the development of the corresponding wireless power changers.First,it reviews the three different models describing magnetic resonance coupled wireless transmissions.The models include the coupled mode theory,the port network model,and the mutual inductance model.More specially,it explains in details the port network model and the mutual inductance model to provide theoretical guidelines for high-frequency power amplifiers design and optimization as well as the optimizing direction of the receiving and sending.Second,it details the design and optimization of two class E power amplifiers working on different frequencies.It covers the topology of the class E circuit,an appropriate signal source and a drive circuit design,a switch tube selection,and the matching circuit design.Third,it designs and develops two different resonant coils.Also,it optimizes the geometry and parameters of the coils to obtain a maximum coupling coefficient between transmitting and the receiving coils.The main content:In the same area,with the coupling coefficient of the receiving and sending coils as the goal to optimize the parameters of the circular plane coil and design a planar coil with a natural frequency near 6.78MHz.Finally,two prototype wireless power changers,with a charging distance from 20 mm to 80 mm,are developed and tested,validating the feasibility and advantages of the proposed chargers.