Equivalent circuits for repeater antennas used in wireless power transfer via magnetic resonance coupling

The demand for wireless power transfer via magnetic resonance coupling is increasing. Magnetic resonance coupling is a new technology that achieves power transfers across a large air gap by using transmitting and receiving antennas. However, repeater antennas can enable power transmission across an even larger distance. These repeater antennas without cross coupling can be expressed as a T-type equivalent circuit. Equivalent circuits that include cross coupling and mutual inductance, which is related to the antenna position, have not been studied. In this paper, a novel way to represent a repeater antenna by an equivalent circuit and a way to determine the mutual inductance are proposed and verified by performing an electromagnetic field analysis and experiment. (c) 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(1): 5162, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22360