Localization system using resonant magnetic coupling factor for improving efficiency in wireless power transfer

Wireless power transfer (WPT) is widely used in portable devices with the advantage of flexibility and convenience. This paper proposes a cooperative multiple coil matrix transmitter (CMCM) structure. This design allows the mobile device receiver coil to be freely placed above the wireless charging pad which can select the appropriate transmitter coils to activate according to the location of the mobile device. The receiver position can be detected by measuring the coupling factor between the transmitter and the receiver coils with a grid searching algorithm. The primary windings selected to be activated for charging are decided by the receiver position.