WIRELESS POWER REPEATER AND METHOD THEREOF

• US 20140203662A1
• Filed: 07/13/2012
• Published: 07/24/2014
• Est. Priority Date: 09/09/2011
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Bae, Su Ho
• Granted Patent: US 9,680,336 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/502 the energy repeater being integrated together with the emitter or the receiver
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

Disclosed is a wireless power transmission apparatus to wirelessly transmit power to a wireless power receiving apparatus by using resonance. The wireless power transmission apparatus includes a transmission part including a transmission coil to receive the power from a power supply to generate a magnetic field, a transmission resonance coil to transmit power received therein from the transmission coil, and a plurality of repeating coils placed in the transmission resonance coil to repeat the power, a detection part to detect a position of the wireless power receiving apparatus placed on the transmission part, and a controller to determine a repeating coil corresponding to the position of the wireless power receiving apparatus and perform a control operation to transmit power through the repeating coil.

Claims

1. A wireless power transmission apparatus to wirelessly transmit power to a wireless power receiving apparatus, the wireless power transmission apparatus comprising:

a transmission part including a transmission coil to receive the power from a power supply to generate a magnetic field, a transmission resonance coil to transmit power received therein from the transmission coil, and a plurality of repeating coils placed in the transmission resonance coil to repeat the power;

a controller for controlling the repeating coils such that one of the repeating coils has a resonance frequency equal to the resonance frequency of the transmission resonance coil; and

a detection part for detecting a variation of current in the transmission part;

wherein the controller determines one of the repeating coils according to the variation of the current to transmit the power through one of the repeating coils.

2. The wireless power transmission apparatus of claim 1,

wherein

the controller controls the repeating coils by adjusting an impedance of each of the repeating coils.

3. The wireless power transmission apparatus of claim 1, wherein the current in the transmission part reduces if the wireless power receiving apparatus is placed on one of the repeating coils, thereby detecting the variation of the current.

4. The wireless power transmission apparatus of claim 1, wherein the detection part comprises a detection coil for detecting an intensity of the magnetic field generated from the transmission resonance coil and a current detector for detecting the variation of the current by converting the magnetic field detected in the detection coil into the current.

5. The wireless power transmission apparatus of claim 1, wherein the controller sequentially changes one of the repeating coils among the repeating coils to detect the variation of the current corresponding to each of the repeating coils.

6. The wireless power transmission apparatus of claim 1, wherein the controller presets a critical value for comparing with the variation of the current to determine one of the repeating coils.

9. The wireless power transmission apparatus of claim 1, wherein the controller repeatedly controls the repeating coils according to a preset period of time.

10. The wireless power transmission apparatus of claim 1, wherein the repeating coils are arranged in a lattice form or in a matrix form in the transmission part.

11. The wireless power transmission apparatus of claim 1, wherein the repeating coils divide the transmission part into a plurality of uniform regions.

12. The wireless power transmission apparatus of claim 1, wherein a radius formed by the repeating coils is greater than a radius formed by a receiving resonance coil of the wireless power receiving apparatus.

13. The wireless power transmission apparatus of claim 1, wherein the repeating coils have variable capacitors, and wherein the controller controls the repeating coils by adjusting capacitance values of the variable capacitors.

16. The wireless power transmission apparatus of claim 1, wherein the repeating coils have fixed capacitors, wherein the controller controls the repeating coils by controlling switches parallel-connected to both terminals of the fixed capacitors.

18. The wireless power transmission apparatus of claim 16, wherein the controller opens a switch of one of the repeating coils and closes switches of a remainder of the repeating coils.

7-8. -8. (canceled)

14-15. -15. (canceled)

17. (canceled)

19. A method of wirelessly transmitting power by a wireless power transmission apparatus including a plurality of repeating coils to wirelessly transmit the power to a wireless power receiving apparatus, the method comprising:

controlling the repeating coils such that one of the repeating coils has a resonance frequency equal to a resonance frequency of the wireless power receiving apparatus;

detecting a variation of a current in the wireless power transmission apparatus;

determining one of the repeating coils corresponding according to the variation of the current; and

transmitting the power through one of the repeating coils.

20. The method of claim 19, wherein the controlling of the repeating coils sequentially changes one of the repeating coils among the repeating coils to detect the variation of the current corresponding to each of the repeating coils.

21. The method of claim 19, wherein the controlling of the repeating coils repeatedly controls with the repeating coils according to a predetermined period of time.

22. The method of claim 19, wherein the current in the transmission part reduces if the wireless power receiving apparatus is placed on one of the repeating coils, thereby detecting the variation of the current.

23. The method of claim 19, wherein the repeating coils have variable capacitors, and wherein the controlling of the repeating coils adjusts capacitance values of the variable capacitors.

24. The method of claim 19, wherein the repeating coils have fixed capacitors, and wherein the controlling of the repeating coils controls switches parallel-connected to both terminals of the fixed capacitors.

25. The method of claim 23, wherein the controlling of the repeating coils opens a switch of one of the repeating coils and closes switches of a remainder of the repeating coils.