Adaptive Wireless Power Transfer System With Relay Transmission and Communication

Wireless power transmission (WPT) systems have been increasingly utilized for wireless charging of electric vehicles. However, most research efforts or commercial products only address wireless power transmission but not wireless data communication. In addition, limitation of the transmission range is always a gap obstructing its popularity. Accordingly, this article presents a novel WPT scheme incorporating both relay transmission and magnetic field data communication. For power transmission, a resonant inverter with pulsewidth modulation was developed using relay coils to induce longer distance alternating current. For data transmission, a magnetic field communication system based on impedance changes and not reliant on extra radio frequency links was realized. Fuzzy compensation was used to stabilize the transmission of both power and data to counter changes in mutual inductance between coils. Phase-shift keying was utilized to generate digital signals for data transmission. Our experimental prototype was tested and verified to simultaneously transmit power and data in compliance with SAE TIR J2954 specifications using real-world experiments.