Research On Enhanced Coplanar Wireless Power Transfer Using Soft Magnetic Ferrite

Wireless power transmission(WPT)is developing rapidly as an emerging technology.Among various WPT technologies,the most popular among researchers is magnetically coupled resonant wireless power transmission(MCR-WPT),which is an efficient middle-range wireless power transfer technology.In WPT systems,most of them are coaxial WPT systems.The coplanar wireless power transmission system has its advantages,but the coplanar WPT system has low transmission efficiency due to the low coupling coefficient of adjacent coils and unstable power.To solve this problem,this paper proposes a MCR-WPT structure.A low-profile,high-permeability,low-loss soft magnetic ferrite is inserted between adjacent coplanar coils to improve the coupling coefficient of adjacent coils and expand System bandwidth significantly improves transmission efficiency and stabilize power.The main content of this paper is to Research on enhanced coplanar wireless power transfer using soft magnetic ferrite,this article includes the following works:(1)The important parameters and basic analysis theories in the system are introduced.After comparing the coupled-mode theory,circuit theory and filter theory,the system is analyzed in depth using circuit theory.(2)The basic principles of the MCR-WPT system are introduced,and the series-series basic structure of the system is analyzed.(3)The Maxwell3D and ADS are used to simulate the traditional coplanar WPT system,and use the simulation data to explain the problem and analyze the root cause.After introducing the properties of soft magnetic ferrite,a solution is proposed to add soft magnetic ferrite structure.(4)Design simulation and parameter scanning corresponding to the structure of soft magnets used in coplanar WPT systems,determine the specific specifications of the soft magnets and expand the structure into a three-coil WPT system,and further analyze the voltage-load properties and cross-coupling effects of the three-coil WPT system.(5)Through the experimental results and parameter analysis,it is proved that the soft magnetic ferrite structure used in the coplanar WPT system can improve the system efficiency,expand the bandwidth,enhance the coupling of adjacent coils and suppress cross coupling.And proved the voltage-load properties of the system,and analyze its expandable structure.