Self-Resonant Capacitive Power Transfer System Leveraging Printed-Circuit-Board Coupler with Integrated Compensation Inductance

This paper presents the self-resonant capacitive power transfer (CPT) concept leveraging a printed-circuit-board (PCB) coupler. The proposed CPT coupler consists of four identical PCB-coil-based plates, in which the multiple-turn spiral copper traces work as capacitive plates with compensation inductance integrated, achieving a compact, lightweight, and low-cost CPT system. Modeling and analysis of the self-resonant CPT system are provided, and a 30 W CPT prototype with four 210mm × 210mm circular PCB-coil plates is implemented to validate the proposed design. With transfer distances of 3mm, 6mm, and 12mm, the implemented CPT prototype demonstrates the power transfer capability of 27.09W, 22.83W, and 19.36W with the peak AC-DC efficiency of 85.38%, 82.96%, and 76.73%, respectively.