Research On Wireless Charging System For UAV With Position Capture Function

With the development of science and technology,the application scenarios of Unmanned Aerial Vehicle are becoming more and more extensive.They are not only used in the military field,but also bring many conveniences to people's lives.The application of UAVs has broad prospects.However,the UAVs cannot be accurately controlled during long-distance flight,and the charging problem of the UAVs limits its wider application.Therefore,the wireless charging of the UAVs has great development potential.The wireless energy transmission technology used in the charging of UAVs can give full play to its advantages.It can be freed from the shackles of electric wires when charging,and it is more portable.Due to the limited position accuracy of the UAVs when it is parked,the area of the UAVs wireless charging platform is relatively large,which faces the problem of low system efficiency.Therefore,this topic will design a UAVs wireless charging system with a landing position capture function,which can capture the landing position of the UAVs,switch different coils,and improve the efficiency of the system.This topic will analyze the theory of loosely coupled transformers for wireless transmission and derive two circuit models for loosely coupled transformers.Based on the derived circuit models,analyze the impact of changes in the mutual inductance of loosely coupled transformers on the output power of wireless energy transmission systems;For the characteristics of UAVs wireless charging,select the types of primary and secondary coils of loosely coupled transformers;calculate the mutual inductance and coupling coefficient of loosely coupled transformers based on finite element technology,and analyze and optimize the design.In order to improve the efficiency of charging,the compensation network for wireless energy transmission including low-order S compensation and P compensation and high-order LCC compensation will be analyzed,and the calculation formula of the compensation network parameters will be deduced to achieve zero input impedance and loadindependent Constant voltage output.Due to the large difference between the primary and secondary side areas of the UAVs wireless charging platform,this topic will use a modular stacking method to design the primary coil,analyze and design the control strategy of coil switching,and effectively capture the location of the UAVs landing point to maximize system efficiency.In addition,the full-bridge inverter is modeled and closed-loop controlled to improve the stability of the output voltage and improve the performance of the system.Finally,a prototype UAVs wireless charging platform was designed and built based on theoretical analysis,which can capture the position of the UAVs and switch the coil,achieve 50 W power transmission,and the working efficiency is up to 79.3%.