A High Q Dual E-Shaped Defected Ground Structure for Wireless Power Transfer Applications

Dual E-shape Defected Ground Structure (DGS) resonator coupled back to back for medium range non-radiative Wireless Power Transfer (WPT) is presented in this paper. The proposed design is based around the concept of resonant inductive coupling for power transfer and consists of E-shaped defect etched in the ground plane of the substrate. The design incorporates capacitive loading for miniaturization and is supported by analytical design procedure. An equivalent parallel RLC resonant circuit in conjunction with coupled mode theory (CMT) and S-parameters aids in the understanding of the proposed WPT system. A prototype, on Rogers RO4350B substrate, has been developed to operate at 0.27 GHz frequency and takes a board size of 20×20 mm
²
. A very good agreement between the simulated and measured results demonstrate the effectiveness of the proposed technique. The achieved performance significantly improves the efficiency of the DGS based WPT systems reported so far.