Design of Efficient Double-Sided LC Matching Networks for Capacitive Wireless Power Transfer System

Abstract

Matching networks are important for capacitive wireless power transfer (CWPT) systems as they provide necessary voltage gain and impedance compensation. The voltages across coupling capacitors greatly affect the transmitted power and efficiency. This paper introduces a method to design double-sided LC matching networks for the CWPT system. The ratio of the voltage across the primary side to the voltage across the secondary side is discussed to realize the required transmitted power and optimize the efficiency of the matching networks. The requirement of zero-voltage switching (ZVS) of the inverter stage is satisfied based on the impedance analysis of the matching networks. The design process is developed based on the mathematical model and verified in simulation for a 1kW CWPT system at 6.78MHz.