High-Misalignment Tolerance WPT System for UAV by Symmetric Rotating Magnetic Field

This paper proposes an novel solenoid magnetic coupler for omnidirectional wireless charging of unmanned aerial vehicles (UAVs). The magnetic coupler features asymmetry compensation, a compact structure, high rotational and misalignment tolerance, and low magnetic leakage interference. The transmitting coils consist of three groups of solenoid coils, each comprising a large coil and a small coil connected in series. The small coil compensates for the uneven coupling caused by axial misalignment of the UAV. The excitation current phase difference of 120° in each transmitter coil group generates rotating magnetic field. The transmitting coils primarily produce horizontal magnetic fields with minimal vertical components, significantly reducing electromagnetic interference with UAV equipment. Two groups of receiving solenoid coils are conformally installed on the UAV landing gear. The topology, where each group of receiving coils is rectified and then connected in series, compensates for the uneven coupling caused by radial misalignment. Simulation results indicate that the system maintains a stable received power of 379W-477W under angular offsets of 0-360° and positional offsets of ±60mm, demonstrating excellent misalignment tolerance.