Wireless power transmitter and method of transmitting power thereof

• US 9,287,736 B2
• Filed: 11/26/2012
• Issued: 03/15/2016
• Est. Priority Date: 11/25/2011
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: Korea Electrotechnology Research Institute, LG Innotek Company Limited (LG Corporation)
• Inventors: Lee, Ki Min, Kim, Kwan Ho, Kim, Jin Wook, Park, Young Jin, Son, Hyeon Chang, Lee, Won Tae
• Primary Examiner(s): Jackson, Stephen W
• Application Number:
  US13/685,305
• Publication Number:
  US 20130134794A1
• Time in Patent Office: 1,205 Days
• Field of Search: 307/104
• US Class Current: 1/1
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

Disclosed are a wireless power transmitter and a method of transmitting power thereof. The wireless power transmitter to wirelessly transmit power to a wireless power receiver includes a transmission coil to receive power from a power supply apparatus, and a transmission resonance unit to transmit the power received therein from the transmission coil to the wireless power receiver using resonance. The transmission resonance unit includes an inner loop, and an outer loop connected to the inner loop while surrounding the inner loop.

Claims

1. A wireless power transmitter to wirelessly transmit power to a wireless power receiver, the wireless power transmitter comprising:

a transmission resonance unit to transmit the power to the wireless power receiver using resonance,

wherein the transmission resonance unit comprises a plurality of resonant coils,

wherein the plurality of resonant coils comprises;

an inner loop and

an outer loop connected to the inner loop while surrounding the inner loop;

a switch unit configured to select at least one of the plurality of resonant coils corresponding to a region in which the wireless power receiver is detected; and

an inductor and a capacitor configured to constantly maintain a resonance frequency of the selected resonant coil for power transmission to the wireless power receiver.

2. The wireless power transmitter of claim 1, wherein the inner loop and the outer loop are formed by winding one conductive line at least one time, and a number of winding turns of the inner loop is equal to or different from a number of winding turns of the outer loop.

3. The wireless power transmitter of claim 1, wherein the inner loop and the outer loop have one of a circular shape, a rectangular shape, and an oval shape.

4. The wireless power transmitter of claim 1, further comprising a distribution coil to transmit the power to the resonant coil corresponding to the region, in which the wireless power receiver is detected, among the resonant coils.

5. The wireless power transmitter of claim 4, wherein the switch unit comprises a plurality of switches, and each switch is paired with each resonant coil to connect the resonant coil corresponding to the region, in which the wireless power receiver is detected, to the distribution coil.

6. The wireless power transmitter of claim 1, wherein the capacitor includes a variable capacitor to constantly maintain the resonance frequency of the selected resonant coil for power transmission to the wireless power receiver.

7. The wireless power transmitter of claim 5, wherein the resonant coil corresponding to the region, in which the wireless power receiver is detected, among the resonant coils is connected to the distribution coil in series.

8. The wireless power transmitter of claim 1, further comprising a detector to detect an approaching state of the wireless power receiver.

9. The wireless power transmitter of claim 8, wherein the detector comprises a detection coil to detect intensity of a magnetic field formed in each resonant coil.

10. The wireless power transmitter of claim 5, wherein each switch is a micro-electro-mechanical system switch.

13. A recording medium having a program to execute a method of transmitting power of a wireless power transmitter claimed according to claim 10.

16. The wireless power transmitter of claim 1, wherein the inductor includes a variable inductor to constantly maintain the resonance frequency of the selected resonant coil for power transmission to the wireless power receiver.

11. A method of transmitting power of a wireless power transmitter that wirelessly transmits power to a wireless power receiver, the method comprising:

detecting an approaching state of the wireless power receiver;

selecting at least one of a plurality of resonant coil corresponding to a region, in which the wireless power receiver is detected, according to a detection result;

determining a change state of a resonance frequency of the selected resonant coil according to the selection of the resonant coil corresponding to the region in which the wireless power receiver is detected; and

matching the resonance frequency of the selected resonant coil with a resonance frequency of a resonant coil of the wireless power receiver, if the resonance frequency of the selected resonant coil is changed; and

transmitting the power to the wireless power receiver using resonance through the matched resonance frequency by the resonant coil corresponding to the region in which the wireless power receiver is detected.

12. The method of claim 11, further comprising:

checking the changed resonance frequency and

changing the checked resonance frequency to the resonance frequency of the wireless power receiver using an inductor and a capacitor.

14. A recording medium having a program to execute a method of transmitting power of a wireless power transmitter claimed according to claim 11.

15. A recording medium having a program to execute a method of transmitting power of a wireless power transmitter claimed according to claim 12.