Full-Duplex High-Speed Simultaneous Communication Technology for Wireless EV Charging

Abstract

This letter presents a novel simultaneous wireless power and data transmission (SWPDT) system for wireless electric vehicle (EV) charging. The data carrier is injected and extracted by a plug-and-play toroidal-core inductor. Two data carriers of 5 and 6.25 MHz are adopted to achieve bidirectional and full-duplex communication using frequency-division multiplexing. Differential quadrature phase-shift keying modulation is achieved by a Class-E amplifier in the data transmitter. An analog switch circuit is designed to demodulate the data carrier in the data receiver. The proposed method is verified by a prototype that achieves up to 64 kbps full-duplex data transmission under 3.3 kW power transfer. The bit rate and interference immunity of data transmission are greatly improved compared to the reported SWPDT systems, which makes it possible to realize high-speed simultaneous communication in the kilowatt-level wireless EV charging.