US 11,757,311 B2
Wireless power transmitters and associated base stations for transmitting power at extended separation distances
Md Nazmul Alam, Lombard, IL (US)
Assigned to NuCurrent, Inc., Chicago, IL (US)
Filed by NuCurrent, Inc., Chicago, IL (US)
Filed on Dec. 23, 2020, as Appl. No. 17/133,153.
Prior Publication US 2022/0200361 A1, Jun. 23, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. H02J 50/70 (2016.01); H01F 27/28 (2006.01); H02J 50/90 (2016.01); H02J 50/12 (2016.01)
CPC H02J 50/70 (2016.02) [H01F 27/2823 (2013.01); H02J 50/12 (2016.02); H02J 50/90 (2016.02)] 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 360 kHz, the power transmitter comprising:
a control and communications unit;
an inverter circuit configured to receive input power and convert the input power to a power signal;
a coil configured to transmit the power signal to a power receiver, the coil formed of a continuous conductive wire comprising wound Litz wire, the continuous conductive wire having a first end and a second end, the coil comprising a first coil portion extending from the first end and a second coil portion extending from the second end, wherein the first coil portion is connected in series to the second coil portion, the first coil portion comprising a first inner edge and a first outer edge, the second coil portion comprising a second inner edge and a second outer edge; and
a ferrite shielding having a cavity, the ferrite shielding comprising a magnetic core having an outer surface, a magnetic backing including a top surface and an outer edge, and a magnetic ring including an inner surface, wherein the magnetic core is positioned on the top surface of the magnetic backing and the magnetic ring is positioned on the top surface and at the outer edge of the magnetic backing, wherein the outer surface of the magnetic core, the top surface of the magnetic backing, and the inner surface of the magnetic ring define the cavity of the ferrite shielding that is below a top face of the magnetic ring,
wherein the first coil portion is positioned within the cavity of the ferrite shielding such that the first inner edge of the first coil portion surrounds the outer surface of the magnetic core and the first outer edge of the first coil portion is surrounded by the inner surface of the magnetic ring,
wherein the second coil portion is positioned above the top face of the magnetic ring and between the inner surface of the magnetic ring and the outer edge of the magnetic backing, wherein the second inner edge of the second coil portion surrounds the first outer edge of the first coil portion.