Superconducting Inductive Wireless Power Transfer System With Underground Cryogenic Transmitter Structure for Electric Vehicle Charging

This paper presents a high frequency high power superconducting inductive wireless power transfer system (WPT) for electric vehicle (EV) charging. There are two major contributions. First, an emerging Gadolinium Barium Copper Oxide (GdBaCuO) based high temperature superconducting (HTS) tape is adopted, targeting minimizing power loss on the magnetic coupler, and enhancing efficiency of the wireless charger. Second, a superconducting wireless charging infrastructure with underground cryogenic structure is proposed to realize a HTS transmitter-copper receiver configuration for practical EV charging scenarios. HTS based- and a copper based WPT system prototypes are implemented with liquid nitrogen (LN<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>) cooling at 500kHz frequency for comparative investigations. Experiments first validate the efficiency enhancement of the HTS based WPT system compared to copper-based counterpart at a relatively lower output power of 1kW. Then experiments further validate the power transfer performance of the HTS WPT system, with 3.44 kW output power at a 95.05% dc–dc efficiency, and the peak efficiency achieves 97.01% at 1.87 kW output power.