Multiple-Channel Coupling Effect Observation for In-Flight Wireless Charging of Drones

Abstract

Multiple-drone in-flight wireless charging offers a cost-effective solution for energy replenishment in long-range drone operations. Since multiple transmission channels impact each other, the conventional mitigation of single-channel mutual inductance disturbance cannot be directly utilized for in-flight wireless charging of drones, which has been nearly unexplored in previous studies. To address this challenge, this article presents a multiple-coupling-observed multi-CC output control scheme. The proposed scheme leverages a multiresonant LCC/P topology to extract phase information from parallel branch currents on the transmitter side, enabling real-time monitoring of multiple mutual inductances without requiring load information. Using the monitored mutual inductance, the scheme regulates constant current (CC) outputs for multiple receivers from a single transmitter, eliminating the need for control, detection, or communication on the receiver side, which contributes to drone lightweighting. Experimental results demonstrate that the proposed method achieves mutual inductance monitoring errors below 2.5%, maintains steady-state current variations under 5.5% after mutual inductance changes, and effectively suppresses output current fluctuations during continuous mutual inductance disturbances. These findings confirm that the proposed scheme effectively ensures stable CC charging in multidrone in-flight wireless power transfer (WPT) systems.