Investigation on threshold distance for efficiency enhanced wireless power transfer using bulk metamaterial

Recently, metamaterials has been emerged as one of the potential candidate for enhancing the efficiency of resonator coupled wireless power transfer (WPT) systems. This paper presents results of experimental investigation on metamaterial enhanced WPT System. Isotropic bulk metamaterial structure has been fabricated by assembling 5 × 5 × 1 array of three turn spiral resonators. Measurements show that the designed metamaterial structure has a great potential in extending the power transfer distance of resonator coupled WPT System. Also we have identified that there is a certain threshold for distance between transmitter and receiver resonators beyond in which the power transfer efficiency is enhanced. The threshold is attributed to the loss of the metamaterials.