US 12,261,459 B2
Wireless power systems with foreign object detection
Adam L. Schwartz, Redwood City, CA (US); Niloofar Rashidi Mehrabadi, Santa Clara, CA (US); and Hossein Sepahvand, Santa Clara, CA (US)
Assigned to Apple Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Jun. 1, 2023, as Appl. No. 18/327,750.
Application 18/327,750 is a continuation of application No. 17/109,793, filed on Dec. 2, 2020, abandoned.
Claims priority of provisional application 63/012,813, filed on Apr. 20, 2020.
Claims priority of provisional application 62/943,043, filed on Dec. 3, 2019.
Prior Publication US 2023/0307962 A1, Sep. 28, 2023
Int. Cl. H02J 50/60 (2016.01); H02J 50/12 (2016.01); H02J 50/70 (2016.01); H02J 50/80 (2016.01)
CPC H02J 50/60 (2016.02) [H02J 50/12 (2016.02); H02J 50/70 (2016.02); H02J 50/80 (2016.02)] 29 Claims
OG exemplary drawing
 
1. A wireless power transmitter comprising:
wireless power transmitting circuitry having a wireless power transmitting coil that transmits wireless power signals; and
control circuitry coupled to the wireless power transmitting circuitry that:
measures a present quality factor of the wireless power transmitting coil;
determines a change between the measured present quality factor and a baseline quality factor;
responsive to the change between the measured present quality factor and the baseline quality factor being less than a threshold, continues to measure the present quality factor of the wireless power transmitting coil and determine the change between the measured present quality factor and a baseline quality factor;
responsive to the change between the measured present quality factor to the baseline quality factor exceeding the threshold, attempts to initiate digital communication with a wireless power receiver; and
responsive to initiation of digital communication with the wireless power receiver, updates the baseline quality factor based on one or more recently measured present quality factors.