Electric and Magnetic Design of a Deployable WPT System for Industrial and Defense UAV Applications

Filip Rosu,Alina Badescu

doi:10.3390/electronics10182252

Filip Rosu, Alina Badescu

Open Access

https://doi.org/10.3390/electronics10182252

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Journal: Electronics	Publication Date: Sep 13, 2021
Citations: 1	License type: CC BY 4.0

Affiliation: Polytechnic University of Bucharest

Abstract

The following paper presents a highly efficient wireless power transfer (WPT) system for unmanned aerial vehicle (UAV) applications. The proposed system is designed as a deployable landing pad, where UAVs can be efficiently charged at distances up to 20 cm, while the UAV is landing. The operation frequency is 50 kHz. The current work presents two major contributions that help improve this aspect: a novel RX charging pad geometry and an unconventional design of a low-voltage, high-power DC–AC inverter using discrete MOSFET transistors. Both the pad’s geometry and the inverter are designed specifically for UAV applications. The input DC to output AC system efficiency peaks at approximately 95%. The peak efficiency is obtained at power transfers of 625 W. A major difference between the present design and traditionally used state-of-the-art systems is the low DC supply voltage requirement of just 24 V, compared with typical values that range from 50 up to 300 V at similar output power.

Highlights

During recent years, the importance of unmanned aerial vehicle (UAV) systems has grown exponentially, both in civil and defense applications
The solution proposed in this paper addresses an efficient power transfer in the 200 W–1 kW range [11], at charging distances between 10 and 20 cm
The output power of a wireless power transfer (WPT) system can be expressed as the product between Psu and a factor, Q, that depends on the loaded quality factor [14] of the receiver and the compensation topology

Summary

Introduction

The importance of UAV systems has grown exponentially, both in civil and defense applications. In applications in which UAVs are required to function continuously, such as the latest trend of pollination drones, the autonomy of the system becomes crucial [7] Such systems would greatly benefit from an accessible and remote charging station that can be transported and deployed. The authors use ferrite bars for both transmitter (Tx) and receiver (Rx) charging pads to increase coupling. This is not a practical solution for UAVs that have weight limitations (on the Rx side).

Resonant WPT Systems

Design Specifications of the Charging Pad

Power Inverter Stage

Conclusions