Modeling and Efficiency Characterization of a Resonant Wireless Power Transfer Circuit for Electric Vehicle Charging
Wiam SAYAR
Abstract. Wireless power transmission via resonant inductive coupling offers an attractive option for charging electric vehicles, by reducing the need for physical connectors, thereby enhancing longevity and user-friendliness. Complete resonant wireless power transfer circuit functionality is developed in MATLAB/Simulink for the battery charging of electric vehicles, involving a high-frequency inverter operating at 30 kHz, mutually coupled coils, rectification stages, and a lithium-ion battery rated at 400 V, 100 Ah. The progression of state of charge is estimated using a simplified constant current/constant voltage charging profile. A specific contribution of the work is a numerical efficiency analysis performed as a function of coil separation distance and inductance values, based on a classical two coil resonant model employing coupling coefficient and quality factor relations. The numerical efficiency analysis indicates that, for nominal alignment and identical high-quality inductors, the link may theoretically achieve in excess of 90% efficiency for small air-gap distances, experiencing a rapid decline in efficiency with increasing air gaps as the mutual coupling goes down. These results indicate the high sensitivity of wireless power transfer performance to geometrical layout parameters and provide practical guidance for electric vehicles charging system design.
Keywords
Wireless Power Transfer, Resonant Inductive Coupling, EV Charging, Charging Efficiency, Simulink Modeling
Published online 4/25/2026, 8 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Wiam SAYAR, Modeling and Efficiency Characterization of a Resonant Wireless Power Transfer Circuit for Electric Vehicle Charging, Materials Research Proceedings, Vol. 64, pp 379-386, 2026
DOI: https://doi.org/10.21741/9781644904091-47
The article was published as article 47 of the book Energy Futures
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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