A Misalignment Tolerance and Lightweight Wireless Charging System via Reconfigurable Capacitive Coupling for Unmanned Aerial Vehicle Applications

This letter proposes a novel capacitive power transfer system for the unmanned aerial vehicles (UAVs) with lightweight in receivers and robust misalignment tolerance characteristics. The design and analysis of a reconfigurable capacitive coupler are presented at first. The transmitter adopts four rectangular copper plates, which can be reconfigured according to the landing positions and directions. The receiver includes two hollow cylindrical copper-foil sleeves wrapped at the bottom of UAV landing gears, thereby leading to the adaption of the UAV's structure and the tolerance to lateral-, longitudinal-, and angular misalignment. Then, simulation and prototype experiments are carried out to verify the proposal. The results show that the prototype has low leakage electric flux at the UAV fuselage and can deliver 212.1 W with a dc-to-dc efficiency of 82.5%. Especially the proposal allows UAV to be powered within ±0.76 A of output current variation for different landing positions and directions, and the system dc-to-dc efficiency variation is within ±1%.