US 11,942,799 B2
False notification suppression in wireless power transfer system
Andrew Kovacs, Lafayette, IN (US); and Jason Green, Evanston, IL (US)
Assigned to NuCurrent, Inc., Chicago, IL (US)
Filed by NuCurrent, Inc., Chicago, IL (US)
Filed on Apr. 30, 2021, as Appl. No. 17/245,956.
Prior Publication US 2022/0352762 A1, Nov. 3, 2022
Int. Cl. H02J 50/80 (2016.01); H01F 27/28 (2006.01); H01F 27/36 (2006.01); H01F 38/14 (2006.01); H02J 50/12 (2016.01); H02J 50/60 (2016.01); H02J 50/70 (2016.01); H02J 50/90 (2016.01); H01F 27/24 (2006.01)
CPC H02J 50/80 (2016.02) [H01F 27/28 (2013.01); H01F 27/36 (2013.01); H01F 38/14 (2013.01); H02J 50/12 (2016.02); H02J 50/60 (2016.02); H02J 50/70 (2016.02); H02J 50/90 (2016.02); H01F 27/24 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A power transmitter for wireless power transfer at an operating frequency selected from a range of about 87 kilohertz (kHz) to about 205 kHz, the power transmitter comprising:
a sensing system;
a feedback mechanism;
a control and communications unit configured to provide power control signals to control a power level of a power signal configured for transmission to a power receiver, the control and communications unit including a controller, the controller configured to:
receive object detection data from the sensing system, the object detection data indicative of near field magnetic coupling (NFMC) connectivity with a power receiver,
if the power receiver is detected, based on the NFMC connectivity, reset an alert timer,
if the power receiver is detected, instruct an inverter circuit to provide a power signal to a coil,
if the power receiver is detected and an NFMC disconnect is subsequently detected, determine if an alert timer value for the alert timer is greater than an alert threshold for the alert timer,
if the NFMC disconnect is detected and the alert timer value is greater than the alert threshold, instruct the feedback mechanism to output an alert indicative of the NFMC disconnect,
if the NFMC disconnect is detected and the alert timer value is greater than the alert threshold, instruct the inverter circuit to cease providing the power signal to the coil; and
if the NFMC disconnect is detected and the alert timer value is less than the alert threshold, continue to instruct the inverter circuit to provide the power signal to the coil;
the inverter circuit configured to receive a direct current (DC) power and convert the DC power to the power signal; and
the coil configured to transmit the power signal to the power receiver, the coil formed of wound Litz wire and including at least one layer, the coil defining, at least, a top face.