Design of a GaN-Based, Inductor-less, Wireless Power Transfer System at 40.68 MHz

Abstract

Wireless power transfer systems have attracted tremendous attention over the past decade. The design of most small size, low power, WPT systems; however, utilizes ferrite to shield and redirect the magnetic fields. This add to the weight and bulk of the system. In this paper, a small and extremely lightweight, PCB based, proof-of-concept WPT system is demonstrated. The circuit operates at 40.68 MHz and is capable of 20 W of output power. It utilizes no discrete inductors other than the WPT coils themselves and weights only 7 grams. The following paper shows the design methodology and the inductor elimination technique used to achieve such design.