Effective-Configuration WPT Systems for Drones Charging Area Extension Featuring Quasi-Uniform Magnetic Coupling

This article presents a quasi-uniform magnetic coupling-based effective-configuration wireless power transfer (WPT) system for drones wider-area charging with multiple extended transmitter coils. The extended transmitter coil with two windings is proposed to cooperate with a small receiver coil for misalignment tolerance with efficient and quasi-uniform coupling. The extended coil is worked out by a simulation-based algorithm, which can be implemented by simple and low-cost procedures. Independent-operating multiple extended coils are designed with overlaps and a dynamic topology for low-cost and robust charging area extension according to performance analyses. Moreover, a novel landed position detection method based on the negative coupling characteristic of the extended coils is proposed for system configuration. The design enables cost-effective charging area extension and assists to sense the position of drones. A prototype is established with a charging area nearly 20 times the area of the receiver coil. Experimental results prove the feasibility of the design, which can be applied flexibly.