A 100W 6.78MHz Inductive Power Transfer System for Drones

This paper reports on the design and development of a wireless charging solution for a DJI Matrice 100 quadcopter drone. The system is based on a high frequency inductive power transfer system built with lightweight copper pipe air-core coils at both ends and lightweight electronics at the receive side. The developed system is capable of delivering power to the drone at the same rate as the original wired charger (100W) when landed at any position on the charging pad, regardless of the lateral misalignment or angular orientation. The charging pad is circular with a one-metre diameter, therefore allowing for a lateral misalignment of up to 25cm. The system has an average mains-to-battery efficiency of 70% and enables the drone missions to be completely autonomous as it eliminates the need for human interference for battery recharging or swapping.