	US 12,438,396 B2
	Wireless power transfer object detection circuit and method
Petru Emanuel Stingu, Dallas, TX (US); Kenneth Moore, Dallas, TX (US); Yulong Hou, Shanghai (CN); and Ruwanga Dassanayake, Dallas, TX (US)
Filed by Spark Connected LLC, Dallas, TX (US)
Filed on Dec. 8, 2023, as Appl. No. 18/534,124.
Application 18/534,124 is a division of application No. 17/020,537, filed on Sep. 14, 2020, granted, now 11,881,719.
Claims priority of provisional application 62/899,607, filed on Sep. 12, 2019.
Prior Publication US 2024/0136861 A1, Apr. 25, 2024
Int. Cl. H02J 50/12 (2016.01); A47B 21/06 (2006.01); G01R 33/00 (2006.01); G01R 33/02 (2006.01); G01R 33/07 (2006.01); G01R 33/10 (2006.01); G06F 1/18 (2006.01); H02J 50/00 (2016.01); H02J 50/10 (2016.01); H02J 50/60 (2016.01); H02J 50/80 (2016.01); H02M 3/158 (2006.01)

CPC H02J 50/12 (2016.02) [A47B 21/06 (2013.01); G01R 33/0094 (2013.01); G01R 33/0206 (2013.01); G01R 33/07 (2013.01); G01R 33/10 (2013.01); G06F 1/189 (2013.01); H02J 50/005 (2020.01); H02J 50/10 (2016.02); H02J 50/60 (2016.02); H02J 50/80 (2016.02); H02M 3/1582 (2013.01); A47B 2021/066 (2013.01); A47B 2200/008 (2013.01)]

18 Claims

1. A method comprising:

wirelessly transmitting power using a transmitter LC tank of a wireless power transmitter;

wirelessly receiving power from the transmitter LC tank using a receiver LC tank of a wireless power receiver;

interrupting wirelessly transmitting the power for a slot period;

during the slot period, measuring a receiver signal associated with the receiver LC tank;

transmitting receiver data based on the measured receiver signal to the wireless power transmitter;

determining a power loss associated with wirelessly transmitting the power based on the measured receiver signal;

detecting a metallic object based on the determined power loss; and

measuring an active receiver current flowing through the receiver LC tank before interrupting wirelessly transmitting the power, wherein the power loss is further based on the active receiver current.