Quantifying the Impact of Slow Wave Factor on Closed-Loop Defect-Based WPT Systems

This article reports the impact of the slow wave effect (SWE) on the design, analysis, and performance of defected ground structure (DGS)-based resonators and the associated wireless power transfer (WPT) systems. As a case study, a systematic analysis of closed-loop polygonal DGS-based resonators is developed which enables a unique methodology to trade off the defect shape and, in turn, SWE and the magnetic field to improve the resonator's effectiveness. It is conceptualized and then experimentally demonstrated that the performance of DGS-based resonators is shape-independent for closed-loop defects. Subsequently, these resonators were aptly utilized to develop a WPT system prototype. An excellent agreement between the theoretical and measurement results demonstrates the effectiveness of the presented DGS-type WPT concept in this article.