WIRELESS POWER TRANSMISSION SYSTEM AND METHOD FOR INCREASING COUPLING EFFICIENCY BY ADJUSTING RESONANT FREQUENCY

• US 20130249306A1
• Filed: 01/16/2013
• Published: 09/26/2013
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: KIM, Ki Young, PARK, Eun Seok, RYU, Young Ho, KWON, Sang Wook, KIM, Nam Yun, KIM, Dong Zo, PARK, Yun Kwon, YOON, Chang Wook, CHOI, Jin Sung, HONG, Young Tack
• Granted Patent: US 9,997,959 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 50/50 using additional energy repeaters between transmitting devices and receiving devices
• 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 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00308 Overvoltage protection

Abstract

A wireless power transmission system and a method for increasing a coupling efficiency by adjusting a resonant frequency are provided. A device of the wireless power transmission system includes a resonator configured to transmit a wireless power, and a communication unit configured to receive information from another device. The device further includes a controller configured to determine a power transmission efficiency based on the information, and adjust a resonant frequency of the device, a resonant frequency of a relay device, and a resonant frequency of the other device, if the power transmission efficiency is less than or equal to a predetermined reference efficiency.

Claims

1. A device of a wireless power transmission system, the device comprising:

a resonator configured to transmit a wireless power;

a communication unit configured to receive information from another device; and

a controller configured to

determine a power transmission efficiency based on the information, and

adjust a resonant frequency of the device, a resonant frequency of a relay device, and a resonant frequency of the other device, if the power transmission efficiency is less than or equal to a predetermined reference efficiency.

2. The device of claim 1, wherein the communication unit is further configured to:

transmit the adjusted resonant frequency of the relay device and the adjusted resonant frequency of the other device to the relay device and the other device, respectively.

3. The device of claim 1, wherein the resonator is further configured to:

transmit the wireless power based on the adjusted resonant frequency of the device.

4. The device of claim 1, wherein the controller is further configured to:

repeat the determination of the power transmission efficiency and the adjustment of the resonant frequency of each of the device, the relay device, and the other device until the power transmission efficiency is greater than the predetermined reference efficiency.

5. The device of claim 1, wherein:

the information comprises an amount of the wireless power received at the other device; and

the controller is further configured to

determine an amount of the wireless power transmitted to the other device, and

determine the power transmission efficiency based on the amount of the received wireless power and the amount of the transmitted wireless power.

6. The device of claim 1, wherein the controller is further configured to:

adjust the resonant frequency of each of the device, the relay device, and the other device based on predetermined adjustment information, the predetermined adjustment information comprising information on a change in the resonant frequency of the device, a change in the resonant frequency of the relay device, and a change in the resonant frequency of the other device, based on a predetermined reference resonant frequency.

7. The device of claim 1, wherein:

the resonator comprises a variable capacitor; and

the controller is further configured to adjust a capacitance of the variable capacitor, to adjust a resonant frequency of the resonator to the adjusted resonant frequency of the device.

8. A device of a wireless power transmission system, the device comprising:

a resonator configured to receive a wireless power;

a communication unit configured to

transmit information to another device, and

receive a resonant frequency adjustment message from the other device; and

a controller configured to adjust a resonant frequency of the resonator based on the resonant frequency adjustment message.

9. The device of claim 8, wherein:

the controller is further configured to determine an amount of the received wireless power; and

the information comprises the amount of the received wireless power.

10. The device of claim 8, wherein the controller is further configured to:

verify reception of a resonant frequency of the device that is adjusted by the other device and that is included in the frequency adjustment message; and

adjust the resonant frequency of the resonator to the adjusted resonant frequency of the device.

11. The device of claim 8, wherein:

the resonator comprises a variable capacitor; and

the controller is further configured to adjust a capacitance of the variable capacitor, to adjust the resonant frequency of the resonator.

12. A method in a device of a wireless power transmission system, the method comprising:

transmitting a wireless power;

receiving information from another device;

determining a power transmission efficiency based on the information; and

adjusting a resonant frequency of the device, a resonant frequency of a relay device, and a resonant frequency of the other device, if the power transmission efficiency is less than or equal to a predetermined reference efficiency.

13. The method of claim 12, further comprising:

transmitting the adjusted resonant frequency of the relay device and the adjusted resonant frequency of the other device to the relay device and the other device, respectively; and

transmitting the wireless power based on the adjusted resonant frequency of the device.

14. The method of claim 12, further comprising:

repeating the determining of the power transmission efficiency and the adjusting the resonant frequency of each of the device, the relay device, and the other device until the power transmission efficiency is greater than the predetermined reference efficiency.

15. The method of claim 12, wherein:

the information comprises an amount of the wireless power received at the other device; and

the method further comprises

determining an amount of the wireless power transmitted to the other device, and

determining the power transmission efficiency based on the amount of the received wireless power and the amount of the transmitted wireless power.

16. The method of claim 12, further comprising:

adjusting the resonant frequency of each of the device, the relay device, and the other device based on predetermined adjustment information, the predetermined adjustment information comprising information on a change in the resonant frequency of the device, a change in the resonant frequency of the relay device, and a change in the resonant frequency of the other device, based on a predetermined reference resonant frequency.

17. A method in a device of a wireless power transmission system, the method comprising:

receiving a wireless power;

transmitting information to another device;

receiving a resonant frequency adjustment message from the other device; and

adjusting a resonant frequency of a resonator based on the resonant frequency adjustment message.

18. The method of claim 17, further comprising:

determining an amount of the received wireless power, the information comprising the amount of the received wireless power;

verifying reception of a resonant frequency of the device that is adjusted by the other device and that is included in the frequency adjustment message; and

adjusting the resonant frequency of the resonator to the adjusted resonant frequency of the device.

19. A wireless power transmission system comprising:

a first device configured to

transmit a wireless power,

determine a power transmission efficiency,

adjust a resonant frequency of the first device, a resonant frequency of a relay device, and a resonant frequency of a second device, if the power transmission efficiency is less than or equal to a predetermined reference efficiency, and

transmit the adjusted resonant frequency of the relay device and the adjusted resonant frequency of the second device to the relay device and the second device, respectively;

the relay device configured to relay the wireless power based on the adjusted resonant frequency of the relay device; and

the second device configured to receive the wireless power based on the adjusted resonant frequency of the second device.

20. The wireless power transmission system of claim 19, wherein:

the second device is further configured to

determine an amount of the received wireless power, and

transmit, to the first device, information on the amount of the received wireless power; and

the first device is further configured to

determine an amount of the wireless power transmitted to the second device, and

determine the power transmission efficiency based on the amount of the received wireless power and the amount of the transmitted wireless power.