Single-Contact Excitation and Power Extraction From Metallic Surface Using Synchronized Resonators

This article presents a novel technique for energizing large metallic surfaces via single-contact excitation, enabling power extraction without a return conductor or ground connection. The system uses two one-end-open resonators at 1.4 MHz, separated by ∼1.2 m, and driven by a GaN-based half H-bridge inverter generating a square wave. A theoretical model, based on power injection and absorption incorporating resonator synchronization and surface wave propagation at the dielectric-metal-dielectric boundary, is utilized to explain the power transfer mechanism. The system is validated through ANSYS HFSS simulations and measurement results and achieves ∼55% DC–DC conversion efficiency with 70% efficiency in power converters. Experimental analysis explores the relationship between surface potential and load current, and voltage behavior across the source/load coils under varying load conditions. This scalable approach, which eliminates the need for a physical return path or complex wave-launching structures, establishes a new paradigm for flexible power delivery over metallic surfaces in industrial and automotive applications.