Wireless power transmitting device

Patent metadata

Field	Value
Publication number	US-11283307-B2
Application number	US-201916686041-A
Country	US
Kind code	B2
Filing date	Nov 15, 2019
Priority date	Nov 16, 2018
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

Disclosed herein is a wireless power transmitting device that includes a charging module which is configured to transmit a foreign object sensing signal for sensing at least one of a wireless power receiving device and a foreign object on a charging pad, and which is configured to transmit a wireless power signal for charging the wireless power receiving device, and a control module which is configured to control the charging module such that the wireless power signal and the foreign object sensing signal are transmitted, and which is configured to sense at least one of the foreign object and the wireless power receiving device, based on an output voltage sensed by the charging module, after the foreign object sensing signal is transmitted.

First claim

The invention claimed is:

1. A wireless power transmitting device, comprising:
a charging module configured to perform operations comprising:
transmitting a foreign object sensing signal that enables sensing of one or more objects on a charging pad, the one or more objects comprising at least one of a wireless power receiving device or a foreign object; and
transmitting a wireless power signal that enables charging of at least one wireless power receiving device located on the charging pad; and

a control module connected to the charging module and configured to perform operations comprising:
controlling the charging module to transmit the wireless power signal and the foreign object sensing signal; and
sensing at least one foreign object and at least one wireless power receiving device on the charging pad based on an output voltage that corresponds to the foreign object sensing signal transmitted by the charging module,

wherein the charging module comprises a switch configured to switch on and off to transmit the foreign object sensing signal and the wireless power signal, respectively, and
wherein the control module comprises:
an operation unit connected to the switch and configured to operate the switch to control a transmission of the wireless power signal and the foreign object sensing signal; and
a foreign object sensing unit configured to, based on the output voltage of the foreign object sensing signal sensed between a resonance capacitor and a transmitting coil of the charging module during a transmission of the foreign object sensing signal, sense a location of the at least one foreign object and the at least one wireless power receiving device on the charging pad.

2. The wireless power transmitting device of claim 1 , wherein the charging module comprises:
a transmitting unit configured to perform operations comprising:
transmitting the wireless power signal and the foreign object sensing signal; and
resonating at a first resonance value corresponding to the wireless power signal to transmit the wireless power signal; and

a resonance converting unit configured to change the first resonance value to a second resonance value to transmit the foreign object sensing signal.

3. The wireless power transmitting device of claim 2 , wherein the transmitting unit comprises:
the transmitting coil placed on a substrate; and
a resonance loop placed between the transmitting coil and a surface of the charging pad on which the at least one wireless power receiving device is located.

4. The wireless power transmitting device of claim 3 , wherein the resonance loop comprises:
a loop-structured resonance coil configured to concentrate signals generated in the transmitting coil; and
a capacitor configured to resonate at a specific frequency.

5. The wireless power transmitting device of claim 4 , wherein the resonance coil is configured to resonate at a first range of frequencies higher than a second range of frequencies at which the transmitting coil resonates, the first range of frequencies enabling charging of the at least one wireless power receiving device when the at least one foreign object is detected on the charging pad with the at least one wireless power receiving device.

6. The wireless power transmitting device of claim 3 , wherein the resonance converting unit comprises:
the switch; and
a variable capacitor connected with the switch in parallel and configured to change the first resonance value to the second resonance value based on the switch being off.

7. The wireless power transmitting device of claim 6 , wherein the variable capacitor has a first capacitance value lower than a second capacitance value of a resonance capacitor.

8. The wireless power transmitting device of claim 6 , wherein the operation unit is configured to control the switch to cause a transmission of one of the wireless power signal and the foreign object sensing signal at set time-period intervals.

9. The wireless power transmitting device of claim 6 , wherein, based on the foreign object sensing unit sensing the at least one wireless power receiving device located on the charging pad, the operation unit is further configured to:
control the switch to transmit the wireless power signal; and
repeat switching on and off the switch at set time-period intervals to sense the at least one foreign object on the charging pad.

10. The wireless power transmitting device of claim 6 , wherein the foreign object sensing unit is configured to set reference ranges based on output voltages that correspond to following cases:
a first reference range where the at least one wireless power receiving device is located on the charging pad;
a second reference range where the at least one foreign object and the at least one wireless power receiving device are located on the charging pad; and
a third reference range where the at least one foreign object is located on the charging pad.

11. The wireless power transmitting device of claim 10 , wherein output voltages in the second reference range are higher than output voltages in the first reference range, and output voltages in the third reference range are higher than output voltages in the second reference range.

12. The wireless power transmitting device of claim 1 , wherein the foreign object sensing unit is further configured to:
emit LED light when sensing at least one wireless power receiving device and at least one foreign object; and
emit LED light when sensing at least one foreign object.

13. The wireless power transmitting device of claim 6 , wherein the operation unit is further configured to operate the switch to prevent a transmission of the wireless power signal based on the at least one foreign object being sensed by the foreign object sensing unit.

14. The wireless power transmitting device of claim 10 , wherein the foreign object sensing unit is further configured to sense that the at least one wireless power receiving device is located on the charging pad based on the output voltage of the foreign object sensing signal belonging to the first reference range.

15. The wireless power transmitting device of claim 14 , wherein the output voltage in the first reference range is 0.55 times to 0.7 times as high as a reference voltage corresponding to the foreign object sensing signal.

16. The wireless power transmitting device of claim 10 , wherein the foreign object sensing unit is further configured to sense that the at least one wireless power receiving device and the at least one foreign object are located on the charging pad based on the output voltage of the foreign object sensing signal belonging to the second reference range.

17. The wireless power transmitting device of claim 16 , wherein the output voltage in the second reference range is 0.71 times to 0.9 times as high as a reference voltage corresponding to the foreign object sensing signal.

18. The wireless power transmitting device of claim 10 , wherein the foreign object sensing unit is further configured to sense that the at least one foreign object is located on the charging pad based on the output voltage of the foreign object sensing signal belonging to the third reference range.

19. The wireless power transmitting device of claim 18 , wherein the output voltage in the third reference range is 0.91 times to 1.2 times as high as a reference voltage corresponding to the foreign object sensing signal.

Assignees

• Lg Electronics Inc

Inventors

• Choi Hyengcheul
• Lee Eunsoo
• Kwon Jaesoon
• Kim Hwanyong
• Park Sooyong
• Lee Seong Hun
• Chae Beom Seok

Classifications

• H02J7/44

  between battery management systems and power sources · CPC title

• H02J50/60 Primary

  responsive to the presence of foreign objects, e.g. detection of living beings · CPC title

• H02J50/12

  of the resonant type · CPC title

• H02J50/80 Primary

  involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices · CPC title

• G01V3/00

  Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation · CPC title