WIRELESS POWER TRANSMITTER, WIRELESS POWER RECEIVER AND WIRELESS POWER TRANSMISSION METHOD

• US 20140103737A1
• Filed: 04/24/2012
• Published: 04/17/2014
• Est. Priority Date: 06/08/2011
• 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 9,892,846 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• 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 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices

Abstract

Disclosed is a wireless power transmitter. A wireless power transmitter includes a transmission coil for generating a magnetic field by receiving power from a power source, a transmission resonant coil for transmitting power to a receiving coil by using the magnetic field generated from the transmission coil by using resonance, a detection unit for detecting an approach of the receiving coil and a power regulator for adjusting an output of the power source, which supplies the power, based on the approach of the receiving coil detected by the detection unit.

Claims

1. A wireless power transmitter comprising:

a transmission coil for generating a magnetic field by receiving power from a power source;

a transmission resonant coil for transmitting power to a receiving coil by using the magnetic field generated from the transmission coil by using resonance;

a detection unit for detecting an approach of the receiving coil; and

a power regulator for adjusting an output of the power source, which supplies the power, based on the approach of the receiving coil detected by the detection unit.

2. The wireless power transmitter of claim 1, wherein the detection unit detects an intensity of the magnetic field transmitted from the transmission resonant coil and detects the approach of the receiving coil based on the detected intensity of the magnetic field.

3. The wireless power transmitter of claim 2, wherein the power regulator compares the detected intensity of the magnetic field with a predetermined reference value and reduces transmission power if the detected intensity of the magnetic field is equal to or higher than the reference value.

4. The wireless power transmitter of claim 2, wherein the power regulator compares the detected intensity of the magnetic field with a predetermined reference value and increases transmission power if the detected intensity of the magnetic field is less than the reference value.

5. The wireless power transmitter of claim 1, wherein the detection unit comprises:

a first power detector for converting the power of the power source into DC current;

a detection coil for detecting an intensity of the magnetic field transmitted from the transmission resonant coil;

a second power detector for converting the power generated by the magnetic field detected from the detection coil into DC current; and

a comparator for comparing an output of the first power detector with an output of the second power detector and transmitting a comparison result to the power regulator.

6. The wireless power transmitter of claim 5, further comprising an amplifier for amplifying the DC current converted by the second power detector.

7. The wireless power transmitter of claim 1, further comprising an amplifier for amplifying the power supplied from the power source to transmit the power to the transmission coil.

8. The wireless power transmitter of claim 1, wherein each of the transmission coil and the transmission resonant coil comprises an inductor and a capacitor.

9. A wireless power receiver for wirelessly receiving power from a wireless power transmitter equipped with a detection unit, the wireless power receiver comprising:

a receiving resonant coil for receiving AC power from the wireless power transmitter by using resonance; and

a receiving coil for receiving the received AC power by using electromagnetic induction,

wherein an approach of the receiving resonant coil to the wireless power transmitter is detected by the detection unit.

10. The wireless power receiver of claim 9, wherein the approach of the receiving resonant coil to the wireless power transmitter is detected based on an intensity of a magnetic field transmitted from a transmission resonant coil of the wireless power transmitter coupled with the receiving resonant coil.

11. The wireless power receiver of claim 10, wherein the power transmitted from the wireless power transmitter is adjusted based on the approach of the receiving resonant coil to the wireless power transmitter.

12. The wireless power receiver of claim 9, further comprising a rectifier circuit that receives the AC power from the receiving coil and rectifies the received AC power into DC power.

13-16. -16. (canceled)

17. A wireless power transmitter comprising:

a first coil;

a second coil coupled to the first coil to transmit power by using resonance;

a detection unit for a state of a receiving side; and

a power regulator for adjusting the power according to the detection result of the detection unit.

18. The wireless power transmitter of claim 17, wherein the state of the receiving side is a location of the receiving side.

19. The wireless power transmitter of claim 18, wherein the detection unit detects the location of the receiving side based on an intensity of a magnetic field of the second coil.

20. The wireless power transmitter of claim 17, wherein the detection unit comprises:

a first power detector for detecting a first power of a power source and outputting a first signal;

a second power detector for detecting a second power of the second coil and outputting a second signal; and

a comparator for outputting a control signal according to the comparing result of the first signal with a second signal.

21. The wireless power transmitter of claim 20, wherein the first power is used as a reference value.

22. The wireless power transmitter of claim 20, wherein the detection unit further comprises:

a third coil coupled to the second coil to detect an intensity of a magnetic field of the second coil, the intensity of the magnetic field of the second coil is converted into the second signal by the second power detector.

23. The wireless power transmitter of claim 20, wherein if the second signal is higher than the first signal such that the receiving side moves far away from the transmitter, the power regulator reduces a power or makes a power as zero.

24. The wireless power transmitter of claim 20, wherein if the second signal is lower than the first signal such that the receiving side is accessible to the transmitter, the power regulator increases a power.