Integrated Coupler Design for UAV Free-Positioning Wireless Power Transfer With Inherent Cross- Coupling Utilization and Enlarged Charging Coverage

This paper proposes an advanced framework for wireless charging systems in unmanned aerial vehicles (UAVs) that integrates magnetic coupling structures with multi-coupling LCC-LCC compensation topologies. Unlike existing systems that focus on limited axis misalignment, the proposed system accommodates full 360-degree rotational misalignment, allowing the UAV to land freely and charge in any orientation thanks to the carefully optimized turn numbers and spacings. As a result, the system supports a broad charging zone with lateral misalignments of Δx ∊ [-100 mm, 100 mm], Δy ∊ [-70 mm, 70 mm], and full 360-degree rotational freedom. Under such a large charging area, the proposed coupler consistently delivers key benefits such as quasi-load-independent output and zero-voltage switching (ZVS). The proposed optimized magnetic coupler, by exploiting the inherent cross-coupling capabilities within the multi-coupling LCC-LCC compensation network, effectively expands the ZVS region in the designed charging area.