30 W capacitive wireless power transfer system with 5.8 pF coupling capacitance

Abstract

This paper presents a new capacitive wireless power transfer (WPT) system that achieves effective power transfer even with very low values of coupling capacitance between two metal plates separated by an air-gap. A prototype of the proposed capacitive WPT system has been built and shown to transfer 30 W across two 5-cm by 5-cm metal plates separated by an air-gap of 0.5 cm. The power transfer per unit capacitance of 5.5 W/pF achieved by this system is 20 times greater than the highest value previously reported in literature.