Misalignment Tolerance Improvement of a Wireless Power Supply System for Drones Based on Transmitter Design with Multiple Annular-Sector-Shaped Coils

The application of wireless power transfer (WPT) technology in power replenishment for drones can help to solve problems such as the frequent manual plugging and unplugging of cables. A wireless power replenishment system for drones based on the transmitter design with multiple annular-sector-shaped coils is proposed in this paper, which improves the misalignment tolerance of couplers, enlarges the drone landing area, and reduces the control requirements of drone landing accuracy further. The general analysis model of the proposed transmitter and the numerical calculation method for mutual inductance between energy transceivers are established. Then, the effect of multiple parameters of the proposed transmitter on the variation in mutual inductance is studied. The misalignment tolerance improvement strategy based on the optimization of multiple parameters of the transmitter is investigated. Finally, an experimental prototype of a wireless power replenishment system for drones based on LCC-S compensation topology is designed to validate the theoretical research. Under the same maximum outer radius of 0.20 m and the same mutual inductance fluctuation rate of 5%, compared to single circular transmitter mode, the maximum offset distance of all directions (360 degrees) in the x-y plane is increased from 0.08 m to 0.12 m. As the receiving side position changes, the maximum receiving power and efficiency are 141.07 W and 93.79%, respectively. At the maximum offset position of 0.12 m, the received power and efficiency are still 132.13 W and 91.25%, respectively.