Numerical Analysis of Magnetic-Shielding Effectiveness for Magnetic Resonant Wireless Power Transfer System

摘要

Magnetic radiation phenomena appear inevitably in the magnetic-resonance wireless power transfer (MR-WPT)system,and regarding this problem the magnetic-shielding scheme is applied to improve the electromagnetic performance in engineering.In this study,the shielding effectiveness of a two-coil MR-WPT system for different material shields is analyzed in theory using Moser's formula and Schelkunoff's formula.On this basis a candidate magnetic-shielding scheme with a double-layer structure is determined,which has better shielding effectiveness and coils coupling coefficient.Finally,some finite element simulation results validate the correctness of the theoretical analysis,and the shielding effectiveness with the double-layer shield in maximum is 30 dB larger than the one with the single-layer case.