Advancements in Wireless Power Transfer Technologies for Electric Vehicle Applications

Abstract

Wireless Power Transfer (WPT) has emerged as a transformative technology for Electric Vehicle (EV) charging, promising enhancements in convenience, autonomy, and driving range by circumventing physical plugs. Pre2019 developments encompass both stationary and dynamic (in-motion) charging methods, mainly through inductive coupling and magnetic resonance. Early trials such as Plugless Power's inductive pads at Google (2011), Utah State University's induction-charging Aggie Bus, and Korea’s moving-charger systems (60 kW over 17 cm, later 83% efficiency over 20 cm) validate feasibility. The theoretical framework highlights three WPT modalities: inductive, capacitive, and far-field techniques. Inductive coupling, including coupled magnetic resonance systems (CMRS), remains dominant. Innovations in coil design, EM shielding, multi-coil setups, and system topology have improved transfer range, efficiency, and safety. Dynamic charging corridors, such as Korea and Germany trials, demonstrate the potential for continuous power during motion. Safety considerations led to EMF shielding practices. This paper presents a unified methodology for designing EV-compatible WPT: from method evaluation and coil topology to shielding and infrastructure alignment. Key findings show stationary systems are mature with high efficiency (>90%), whereas dynamic systems face infrastructure challenges and cost barriers, despite range and battery size benefits. Wireless charging reduces user intervention and enables smaller batteries, but suffers from alignment sensitivity, infrastructure cost, and electromagnetic safety concerns. The paper concludes that non-radiative near-field methods (inductive, resonant) offer optimal trade-offs, with growth potential in dynamic implementations. Future work should address standardization, infrastructure cost-effectiveness, interoperable coil designs, and safe, scalable deployments.