Efficiency Enhancement of Wireless Power Transfer System Using MNZ Metamaterials

In this paper, a simple approach for efficiency enhancement of a wireless power transfer system by using mu near zero (MNZ) type of metamaterial is proposed. A single slab containing onesided periodic structures of 3×3 array of meander-line unit cell has been placed between transmitting and receiving coils in the wireless power transfer system. The presented metamaterial structure is less complex than other reported metamaterial structures in the area of wireless power transfer system. The simulation and measurement have been performed with and without the metamaterial slab. Using the metamaterial slab, the maximum efficiency has been obtained about 55.3%, i.e., an improvement of efficiency around 15.7% is obtained compared to a wireless power transfer system without the metamaterials. Interestingly, the proposed wireless power transfer system shows a steady improvement of efficiency even if the distance between the transmitting and receiving coil is increased.