A Magnetic Coupling Structure Design of Wireless Charging UAVs with Multidirectional Misalignment Improvement and Output Fluctuation Suppression

This paper proposes a design of a novel magnetic coupling structure, which is featured a strong anti-misalignment ability for reliable charging to unmanned aerial vehicles (UAVs). The strong tolerance is not only limited to rotational misalignment but also to diagonal, lateral, and longitudinal offsets, thanks to the presented magnetic coupling structure. Specifically, the transmitter (Tx) consists of eight solenoid coils and one regular octagon coil, forming a magnetic field between the center and the periphery. To make use of this field, two rectangular coils are mounted on the landing gears with the consideration of the intrinsic shape and space of the landing gears of commercial UAVs. The air-core receivers also save valuable on-board weight. With the help of such a well-designed coupling mechanism, the presented system can tolerate all 360° rotational misalignments and large-distance horizontal offset, i.e., $(-50\ \text{mm}.-50\ \text{mm})\leq(x, y)\leq(50\ \text{mm},50\ \text{mm})$ .