A Novel Planar Magnetic Flux Concentrator and Its Application in Wireless Power Transfer

This paper presents a planar magnetic flux concentrator (MFC) to reduce the leakage flux and increase the power transmission in the wireless power transfer (WPT) system. The magnetic field distribution in WPT and eddy current distribution in MFC are investigated. The Finite Element Method (FEM) based simulation results show that the magnetic flux density is increased around the centre hole area of the Tx and Rx coils and decreased in the outer area of the Tx and Rx coils. The experiment results demonstrate that the power transfer can be increased using a planar MFC in the WPT system. The equivalent circuits of WPT transformers with and without a planar MFC are also proposed based on the impedance measurement and analysis. The developed equivalent circuits for the Tx and Rx coils of WPT with MFC are proposed based on the impedance analysis.