SPECIAL CONICAL WIRELESS CHARGING SYSTEM FOR DRONES

Abstract

Inductive power transfer systems are nowadays integrated in more and more electromagnetic devices. A potential application of such systems is the wireless charging of autonomous/semi-autonomous drone batteries, these aerial vehicles being used in the last decade for a lot of domestic or military applications. The operating range of these vehicles is limited because their batteries are limited in size, weight and stored energy. Thus, the drone batteries should be charged more often. Wireless charging stations (Wireless Charging System - WCS) spread over a defined operating region can be used for this purpose once the drones are equipped with intelligent algorithms capable of optimally choosing the closest charging support, based on specific parameters such as: the programmed route, the drone position, the battery charge status, WCS locations, weather conditions, etc.
WCS are more flexible and less sensitive to weather conditions (rain, mud, dust, wind, etc.) than classic plug-in charging systems. However, a good alignment of the transmitter and receiver coils of a WCS remains a challenging aspect in harsh weather conditions (strong wind or storm), solving this problem being essential for an efficient charging process.
The solution analyzed in this paper is a WCS for drones capable of operating in difficult weather conditions. The proposed system is able to automatically center the transmitter (Tx) and receiver (Rx) coils and efficiently lock and release the drone using an electromagnetic system. The Tx coil is mounted on a concrete magnetic support, and the Rx coil is mounted on a ferrite plate placed on the underside of the drone. The analysis of the proposed solution and the determination of the characteristics and performances of the proposed system are performed using the Finite Element (FE) method implemented in the professional software package Flux®.