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In this paper, a wireless charging architecture employing a multilevel switched-capacitor (MSC) AC-DC rectifier is investigated. The proposed MSC rectifier features a multilevel design which is scalable to accommodate different power ratings and load ranges. The topology showcases advantages for wireless power transfer (WPT) systems in terms of compactness, efficiency, impedance tunability, and harmonic attenuation. The single-stage active topology is capable of varying its low-distortion staircase input voltage to tune the wireless power transfer system for high system-wide efficiency. A 7-level, 20 W prototype is used to verify the WPT loading and loss analysis. The prototype operates at 150 kHz with up to 3:1 step-down conversion ratio to an output voltage of 5.0 V. The experimental peak DC-to-DC efficiency is 93.8% and the rectifier peak efficiency is 98.3%. The rectifier demonstrates low waveform distortion and high efficiency across many WPT loading conditions, solidifying its place as a strong candidate for wireless power applications.
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This content will become publicly available on December 3, 2026
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 (LN2) cooling at 500 kHz 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 1 kW. 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.
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- PAR ID:
- 10703149
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Open Journal of Power Electronics
- Volume:
- 7
- ISSN:
- 2644-1314
- Page Range / eLocation ID:
- 69 to 78
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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