A Misalignment-Tolerant WPT System for UAVs Based on a Fully Planar Uniform Rotating Magnetic Field

The inability of uncrewed aerial vehicles (UAVs) to land accurately within designated charging areas significantly restricts their wireless power transfer (WPT) applications. To address this challenge, this article proposes a full-plane misalignment-tolerant WPT system based on a self-decoupled flat orthogonal coil pair. The proposed system generates a uniformly distributed horizontal magnetic flux that rotates at a constant angular velocity. At any position and orientation above the transmitter platform, the receiver coil can capture an alternating magnetic flux with a consistent amplitude. This enables the system to achieve full-plane misalignment tolerance, including lateral, longitudinal, and rotational offsets. This article innovatively employs a corrected image current method and genetic algorithms to optimize the coil distribution of the flat orthogonal coils, generating a highly uniform horizontal magnetic flux above the transmitting platform. With phase-shifted currents, a uniformly rotating magnetic flux at the resonant frequency is achieved. The output remains highly stable and unaffected by the UAV’s position or orientation above the platform, without requiring position sensing, frequency adjustment, or other complex control strategies. Experimental results demonstrate that the system exhibits excellent misalignment tolerance, delivering approximately 200 W of output power with a DC–DC efficiency of 88%. The output voltage varies by no more than ±2.5% under ±30 mm longitudinal/lateral misalignments and by only ±3% across a full 360° rotation.