A Single-Input Multi-Output Capacitive Power Transfer System with Enhanced Misalignment Tolerance for UAV Swarm Charging

This paper proposes an electric field-coupled wireless charging system for UAV swarms, capable of simultaneously charging multiple drones through a single transmitter-side setup while demonstrating excellent misalignment tolerance and load decoupling capability. First, a single-input multi-output (SIMO) electric field coupler with simple structure and superior structural adaptability is developed. Parameter optimizations are conducted to enhance misalignment tolerance, and its equivalent circuit model is established through finite element simulations. Second, an LCLC-CLL resonant network is designed to achieve constant current output, multi-load decoupling, and transmitterside load-adaptive zero-phase-angle (ZPA) operation. Finally, an experimental prototype is constructed to validate the theoretical analysis. Experimental findings demonstrate that the system attains a maximum single-load output power of 709.9 W with peak DC-DC efficiency reaching 89.06%. Stable power delivery is maintained across lateral misalignment ranges of [-125 mm, +125 mm] and rotational misalignment up to 240°. The system exhibits robust operational adaptability, sustaining high energy transfer efficiency during both load quantity variations and load imbalance scenarios. Furthermore, its advanced load-decoupling characteristics enable independent charging operation for multiple loads without cross interference, significantly enhancing the flexibility and cost-effectiveness of UAV swarm charging systems.