A Strong Misalignment-Tolerance Wireless Power Transfer System Based on Dynamic Diffusion Magnetic Field for Unmanned Aerial Vehicle Applications

The peculiar structure, restricted payload ability, and inevitable landing position deviation of the unmanned aerial vehicles (UAVs) have become the bottleneck, restricting their wireless power transfer (WPT) applications. To overcome these problems, a dynamic diffusion magnetic field, based on the two-phase transmitting circular coils arranged at intervals, is established by the design of the magnetic structure and excitation current phase. At this time, the receiver can be simplified as a rectangular coil and small magnetic core, which only picks up the horizontal magnetic flux to achieve a compact design. Then, the transmitter self-coupling is analyzed and a decoupling transformer is built for the circulation active power feedback. Finally, a UAV WPT prototype is constructed, and the experimental result indicates that it can transfer 286.7 W with a dc-dc efficiency of 80.3%, and maximum fluctuation of output dc current and dc-dc efficiency are only 0.48 A and 2.1% under the UAV dislocation.