Improvement in Efficiency of Inductive Power Transfer Using Spatial Spiral Layout

Inductive power transfer is one of the most effective ways to provide flexible power for mobile devices. Whereas, in practical application, because of the skin-effect loss and proximity-effect loss, when the inductive power transfer system works at high frequency (MHz), the resistance of coil would increase rapidly. The increase of coil resistance leads to the decrease of power amount and transmission efficiency. Therefore, a spatial spiral layout was proposed, which can significantly reduce the skin-effect and proximity-effect loss at high operation frequency. The special coil structure can significantly decrease the resistance of coil and improve the power amount and transmission efficiency of inductive power transfer system at high frequency operation.