Wireless Power Transfer System Using Class E/F3 Power Amplifier with Second Harmonic Reduction

Abstract

In this paper, we present a high-efficiency wireless power transfer system with design and measurements, for three different types of receivers. The transmitter for the system uses a Class E/F 3 power amplifier with second harmonic reduction to reduce distortion, a resonator, and three different types of receivers. The proposed transmitter uses a harmonic filter to reduce distortion, and is designed to be a load-dependent voltage source, which means that it generates output power according to the load impedance. The resonator is designed to match the impedance of the receivers by using design parameters between the coils of the transmitter and the receivers. The receivers are designed using a rectifier based on four Schottky diodes. Experimental results show that the proposed wireless power transfer system can operate with received power of 17.5∼37.1 W and system efficiency of 71.6∼75.5 % for three types of receivers.