Free-Position Dynamic WPT System Supporting In-Flight Concurrent Charging for Multiple Unmanned Aerial Vehicles

The deployment of external wireless charging infrastructures for unmanned aerial vehicles (UAVs) has faced several challenges, including as the requirement for accurate location, the expensive nature of charging multiple loads, and the absence of system robustness. This article suggests a new spatial magnetic field configuration for transmitting coils in wireless power transfer systems to tackle these problems. The construction features a square base with a rhombus embedded inside it, along with four rectangular sides that are coiled in a noncrossing manner. This configuration ensures a consistent distribution of magnetic field in three dimensions. In order to guarantee that many UAVs are charged simultaneously without interfering with one another, the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCC</i>-S topology is used to accomplish the characteristic of constant current at the main side and constant voltage at the output side. During UAV hovering, output dc–dc is combined with charge management to achieve hovering power supply and constant current charging with minimum size. The experimental results show that when the UAV hovers in the three-dimensional conical space volume above the WPT platform, it maintains a stable output power with an approximately constant 84.5% transmission efficiency. A video file demonstrating wireless charging testing for drones is attached to this article.