Multi‐Receiver MCR‐WPT System Based on Electromagnetic Metamaterials

ABSTRACT To address the problem of low transmission efficiency in three‐receiver magnetically coupled resonant wireless power transfer (MCR‐WPT) systems caused by the large number and small size of receiver coils, this paper proposes two hybrid magnetic negative (MNG) metamaterial arrays, namely, hybrid MNG array 1 and hybrid MNG array 2, operating at 6.78 MHz. These arrays are designed to enhance the transmission efficiency of “flat‐type” and “symmetric‐type” three‐receiver MCR‐WPT systems, respectively. First, based on effective medium theory and resonance principles, three types of MNG units were designed. The magnetic permeability of the metamaterial units was flexibly adjusted according to the spatial positions of the receiver coils, forming the two hybrid MNG arrays. Subsequently, simulation and experimental analyses were conducted to evaluate the effectiveness and safety of the proposed arrays. Experimental results demonstrate that, at a transmission distance of 24 mm, integrating hybrid MNG array 1 and two single‐type MNG arrays into the “flat‐type” system improves the overall transmission efficiency by 29.50%, 19.23%, and 6.86%, respectively. Similarly, integrating hybrid MNG array 2 and three single‐type MNG arrays into the “symmetric‐type” system enhances the efficiency by 26.91%, 6.31%, 11.61%, and 1.14%, respectively. Moreover, the proposed systems maintain high transmission performance even under receiver misalignment. Compared with previous studies, the proposed approach significantly improves transmission performance without introducing additional system complexity, providing a novel and practical solution for high‐efficiency multi‐receiver WPT systems.