Experiments on wireless power transfer with metamaterials

Abstract

In this paper, wireless power transfer based on resonant coupling with metamaterials is studied. We show with numerical studies that the coupling between transmitter and receiver can be enhanced, and the power transfer efficiency can be improved by metamaterials. A prototype wireless power transfer system and a metamaterial is designed and built. Experiment results prove the efficiency improvement with the fabricated metamaterial. The system with metamaterial is capable of transferring power wirelessly at roughly double the efficiency of the same system without a metamaterial. European Conference on Antennas and Propagation (EUCAP)This work may not be copied or reproduced in whole or in part for any commercial purpose. Permission to copy in whole or in part without payment of fee is granted for nonprofit educational and research purposes provided that all such whole or partial copies include the following: a notice that such copying is by permission of Mitsubishi Electric Research Laboratories, Inc.; an acknowledgment of the authors and individual contributions to the work; and all applicable portions of the copyright notice. Copying, reproduction, or republishing for any other purpose shall require a license with payment of fee to Mitsubishi Electric Research Laboratories, Inc. All rights reserved. Abstract-In this paper, wireless power transfer based on resonant coupling with metamaterials is studied. We show with numerical studies that the coupling between transmitter and receiver can be enhanced, and the power transfer efficiency can be improved by metamaterials. A prototype wireless power transfer system and a metamaterial is designed and built. Experiment results prove the efficiency improvement with the fabricated metamaterial. The system with metamaterial is capable of transferring power wirelessly at roughly double the efficiency of the same system without a metamaterial.

Magnetic superlens-enhanced inductive coupling for wireless power transfer

“…[2][3][4] Stimulated by the growing demand in mobile electronic devices and electric vehicles, numerous efforts are now underway to develop new configurations capable of transporting energy wirelessly, and generally seeking to increase the efficiency of all WPT schemes as much as possible. [5][6][7][8][9] WPT techniques have crossed over from research to product development, with several commercial units being offered for charging lowpower consumer [10][11][12] and medical electronics. 13 The majority of contemporary WPT schemes employ a near-field based, inductive coupling mechanism to achieve high transfer efficiency over short distances (1-5 cm); for acceptable efficiency in these schemes, the distance between the source and receiver must be considerably smaller than the dimension of the transmitter or receiver.…”

Magnetic levitation of metamaterial bodies enhanced with magnetostatic surface resonances

“…Alternatively, with a given, attainable current magnitude, one could levitate an object heavier by a large factor, 1/Imμ eff . Loss tangents of order 0.1 are attainable 32,34 in negative-permeability metamaterials at 10 MHz; thus metamaterials could potentially increase the magnetic levitation strength by an order of magnitude.…”

“…Thus, from the design perspective, anisotropic metamaterials 30 are much easier to achieve than their isotropic counterparts. 31,32 Additionally, magnetic resonators can be very thin, planar elements providing strong magnetic response only in the direction normal to their plane. A well-known example of such metamaterial elements are split-ring resonators.…”

“…30 Thin resonators can be stacked with a high number density, providing stronger magnetic response for the select orientation of the magnetic field. The figure of merit for many applications including superlens-based imaging 26,28,33 and wireless power 32,34 is the inverse magnetic loss tangent at the frequency where Reμ(ω) = −1. Assuming the magnetic dispersion model, 9…”

Investigation of negative permeability metamaterials for wireless power transfer

“…Compared to the WPT without NPM, the transmission efficiency is improved from 17% to 47% when using the NPM planes composed by 6×6 units. 4 As the operation frequency of Wang's NPM is high to 27.12 MHz, not easy to implement in a practical application; A. L. Ranaweera investigates a compact NPM which can operate around 6.5 MHz, the proposed NPM is realized on a thin slab using an array of three-turn circle spiral coil. With the structure of 2-slab of 5×5 units, they also achieve a remarkable efficiency improvement.…”