Object detection in wireless charging

Abstract

The present disclosure relates to methods and systems that can reliably detect foreign objects on a wireless charging pad under varying temperatures. In some examples, an object detector can utilize a set of inductive coils included in resonant tanks, and excite the resonant tanks using signals in a range of frequencies including or near a nominal resonant frequency of the resonant tanks. The object detector can detect a metal object based on resistance of a coil increasing and inductance of the coil decreasing. By analyzing the shifts and/or distributions in resonant frequencies and output magnitudes (e.g., output voltage peaks), the object detector can distinguish between changes of frequencies and magnitudes caused by temperature and those caused by foreign objects to accurately detect the foreign objects.

Dependencies are inferred from the claim text.