Investigation of wireless power transfer with 3D metamaterial for efficiency enhancement

Abstract

Metamaterial have shown great power of controlling the EM waves, which is mainly about the propagation property of far field. In this paper, three-dimensional (3D) metamaterials are used in near field wireless power transfer (WPT) system for efficiency enhanced. The 3D metamaterial structure is composed of 4×4×1-array of five-turn spiral resonators. The WPT with bulk metamaterial is investigated theoretically, experimentally, and by simulation. To verify the enhancement of the WPT system by using 3D metamaterial, the four-coil systems integrated with and without bulk metamaterial are investigated by vector network analyzer (VNA). As a result, the maximum efficiency improvement of 20% is obtained with the 3D metamaterials at 1.5m transfer distance. At the same time, the range of efficient power transfer can be greatly extended.