Inductive coil

Abstract

A coil assembly for a wireless power transfer (WPT) system includes a coil carrier tray constructed of a non-conductive, magnetically transparent material that has channels formed therein for receiving a coil. The coil includes a plurality of uninsulated rectangular Litz wire bundles that are woven, braided, or twisted together and then rolled or compressed into a rectangular shape and coated with a non-insulating thin film coating. Each Litz wire bundle, in turn, includes a plurality of uninsulated Litz wire sub-bundles that are woven, braided, or twisted together and then rolled or compressed into a rectangular shape. Each Litz wire sub-bundle, in turn, includes insulated Litz wire strands that are woven, braided, or twisted together and then rolled or compressed into a rectangular shape. The coil design maximizes the amount of conductive material in the channels, maximizing flux density while creating a uniform magnetic flux at the coil surface.

Dependencies are inferred from the claim text.