Progress In Electromagnetics Research
ISSN: 1070-4698, E-ISSN: 1559-8985
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By C. J. Li and H. Ling

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A capacitor-loaded coupled loop structure is investigated for wireless power transfer at 6.78 MHz for a target transmission distance of 1 m. It is shown that the optimal configuration for this structure occurs when the coupled loops are coplanar. Therefore, by converting thick wires into wide strips, a planarized configuration can be achieved. Simulation results are verified in measurement, which shows a 60% overall power transfer efficiency at 1 m. The contribution of different loss mechanisms is examined. Next, power transfer efficiency in the presence of dielectric materials is investigated in simulation and measurement. Additionally, tuning capabilities that arise from the implementation of variable capacitors are shown. Finally, design space exploration is performed to examine design tradeoffs.

C. J. Li and H. Ling, "Investigation of Wireless Power Transfer Using Planarized, Capacitor-Loaded Coupled Loops," Progress In Electromagnetics Research, Vol. 148, 223-231, 2014.

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