Long‐distance and anti‐disturbance wireless power transfer based on concentric three‐coil resonator and inhomogeneous electromagnetic metamaterials

Abstract

SummaryFor wireless power transfer system (WPTS), the deflection of the resonant coil and the increase of the transmission distance will cause a sharp decline in transmission efficiency. This paper presents a novel long‐distance and anti‐deflection wireless power transfer based on concentric three‐coil resonator and inhomogeneous electromagnetic metamaterials (IEM). First, the effective receiving area of the resonator is analyzed, and the anti‐disturbance concentric three‐coil resonator is designed quantitatively. Considering the magnetic field distribution generated by the transmitting coil, this paper proposes and designs IEM with three kinds of effective permeability, which is applied in different design area, respectively. Meanwhile, the finite‐element‐method simulation proves an improvement in magnetic field modulation and flux leakage control when WPTS with IEM is used. The experimental results show that, compared with the traditional one‐coil to one‐coil, the WPTS designed in this paper achieves an increase of 43% in the efficiency at a 90° deflection. Furthermore, the efficiency of WPTS with IEM is 17% and 7% higher than that of WPTS with homogeneous electromagnetic metamaterials (HEM) and without electromagnetic metamaterials. As a result, the design method in this paper can improve the anti‐disturbance capability and increase the transmission distance and efficiency.