Suppression of leakage magnetic field from a wireless power transfer system using ferrimagnetic material and metallic shielding

This paper describes a method to suppress the leakage magnetic field from a wireless power transfer (WPT) system through the use of a ferrimagnetic material and metallic shielding. To demonstrate the advantages of the coil structure with the ferrimagnetic material and metallic shielding, magnetic field distributions and the electrical performance of three different coil structures are investigated via 3D electromagnetic (EM) field solver and SPICE simulation. Results show that the suggested method considerably reduces the leakage magnetic field in the vicinity of the WPT system without significant loss of electrical performance. The simulation results of the suggested coil structure are experimentally verified with a 100 W-class WPT system for an LED TV.