Foreign object detection in inductive coupled devices

摘要

A primary device for inductive power transfer to a secondary device is disclosed. The primary device includes a primary coil, the primary device being configured to (i) operate in a first mode during which the primary coil transfers power through inductive coupling to the secondary device, and (ii) operate in a second mode during which a foreign object is detected. The primary device further includes a primary controller configured to operate the primary coil (i) using a first frequency during the first mode, and (ii) using a second frequency during the second mode. A method to detect a foreign object which is in proximity of an inductively coupled environment of a primary device is also disclosed.