WIRELESS POWER FEEDING SYSTEM

• US 20120161536A1
• Filed: 12/07/2011
• Published: 06/28/2012
• Est. Priority Date: 12/24/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: KAMATA, Koichiro, Okano, Shinya
• Granted Patent: US 9,065,302 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 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• 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: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge

Abstract

A wireless power feeding system includes a power feeding device and a power receiving device. The power feeding device includes a first resonance coil connected to a high-frequency power source through a first matching circuit, and a first control circuit connected to the first matching circuit and a first transmitter-receiver circuit. The power receiving device includes a second resonance coil configured to be in magnetic resonance with the first resonance coil, and a second control circuit connected to a load, a second matching circuit, and a second transmitter-receiver circuit.

Claims

1. A wireless power feeding system comprising:

a power feeding device comprising;

a first resonance coil configured to transmit power from a power source;

a first matching circuit operationally connected to the first resonance coil; and

a first control circuit configured to change an impedance of the first matching circuit in accordance with an instruction received at a first transmitter-receiver circuit through a first antenna; and

a power receiving device comprising;

a second resonance coil configured to be in magnetic resonance with the first resonance coil;

a second matching circuit operationally connected to the second resonance coil;

a second control circuit which is connected to a load and is configured to change an impedance of the second matching circuit; and

a second transmitter-receiver circuit configured to send the instruction from a second antenna.

2. The wireless power feeding system according to claim 1, wherein the first matching circuit and the second matching circuit have an identical circuit configuration.

3. The wireless power feeding system according to claim 1,

wherein the first matching circuit comprises a first element connected to the power source in series, and a second element connected to the power source in parallel, and

wherein the second matching circuit comprises a third element connected to the load in series, and a fourth element connected to the load in parallel.

4. The wireless power feeding system according to claim 3,

wherein the first element and the third element have an identical configuration, and

wherein the second element and the fourth element have an identical configuration.

5. The wireless power feeding system according to claim 3,

wherein the first element and the third element are variable capacitors, and

wherein the second element and the fourth element are variable coils.

6. The wireless power feeding system according to claim 1,

wherein the power source is a high-frequency power source.

7. A wireless power feeding system comprising:

a power feeding device comprising;

a first resonance coil configured to transmit power from a power source;

a first matching circuit operationally connected to the first resonance coil; and

a first control circuit configured to change an impedance of the first matching circuit in accordance with an instruction received at a first transmitter-receiver circuit through a first antenna; and

a power receiving device comprising;

a second resonance coil configured to be in magnetic resonance with the first resonance coil;

a second matching circuit operationally connected to the second resonance coil;

a second control circuit which is connected to a load and is configured to change an impedance oldie second matching circuit; and

a second transmitter-receiver circuit configured to send the instruction from a second antenna,

wherein the first resonance coil is connected to the power source through the first matching circuit.

8. The wireless power feeding system according to claim 7, wherein the first matching circuit and the second matching circuit have an identical circuit configuration.

9. The wireless power feeding system according to claim 7,

wherein the first matching circuit comprises a first element connected to the power source in series, and a second element connected to the power source in parallel, and

wherein the second matching circuit comprises a third element connected to the load in series, and a fourth element connected to the load in parallel.

10. The wireless power feeding system according to claim 9,

wherein the first element and the third element have an identical configuration, and

wherein the second element and the fourth element have an identical configuration.

11. The wireless power feeding system according to claim 9,

wherein the first element and the third element are variable capacitors, and

wherein the second element and the fourth element are variable coils.

12. The wireless power feeding system according to claim 9,

wherein the power source is a high-frequency power source.

13. A wireless power feeding system comprising:

a power feeding device comprising;

a first resonance coil configured to transmit power from a power source;

a first coil connected to the power source;

a first matching circuit operationally connected to the first resonance coil; and

a first control circuit configured to change an impedance of the first matching circuit in accordance with an instruction received at a first transmitter-receiver circuit through a first antenna; and

a power receiving device comprising;

a second resonance coil configured to be in magnetic resonance with the first resonance coil;

a second coil connected to a load;

a second matching circuit operationally connected to the second resonance coil;

a second control circuit which is connected to the load and is configured to change an impedance of the second matching circuit; and

a second transmitter-receiver circuit configured to send the instruction from a second antenna,

wherein the first coil is magnetically coupled with the first resonance coil, and

wherein the second coil is magnetically coupled with the second resonance coil.

14. The wireless power feeding system according to claim 13, wherein the first matching circuit and the second matching circuit have an identical circuit configuration.

15. The wireless power feeding system according to claim 13,

wherein the first matching circuit comprises a fifth element connected to the first resonance coil, and

wherein the second matching circuit comprises a sixth element connected to the second resonance coil.

16. The wireless power feeding system according to claim 15, wherein the fifth element and the sixth element are variable capacitors.

17. The wireless power feeding system according to claim 13, wherein the power source is a high-frequency power source.

18. A wireless power feeding system comprising:

a power feeding device comprising;

a first resonance coil configured to transmit power from a power source;

a first coil connected to the power source;

a first matching circuit operationally connected to the first resonance coil; and

a first control circuit configured to change an impedance of the first matching circuit in accordance with an instruction received at a first transmitter-receiver circuit through a first antenna; and

a power receiving device comprising;

a second resonance coil configured to be in magnetic resonance with the first resonance coil;

a second coil connected to a load;

a second matching circuit operationally connected to the second resonance coil;

a second control circuit which is connected to the load and is configured to change an impedance of the second matching circuit; and

a second transmitter-receiver circuit configured to send the instruction from a second antenna,

wherein the first coil is magnetically coupled with the first resonance coil,

wherein the second coil is magnetically coupled with the second resonance coil, and

wherein the first coil is connected to the power source through the first matching circuit.

19. The wireless power feeding system according to claim 18, wherein the first matching circuit and the second matching circuit have an identical circuit configuration.

20. The wireless power feeding system according to claim 18,

wherein the first matching circuit comprises a fifth element connected to the first resonance coil, and

wherein the second matching circuit comprises a sixth element connected to the second resonance coil.

21. The wireless power feeding system according to claim 20, wherein the fifth element and the sixth element are variable capacitors.

22. A power feeding device comprising:

a first resonance coil configured to transmit power from a power source to a second resonance coil in a power receiving device;

a matching circuit operationally connected to the first resonance coil; and

a control circuit configured to change an impedance of the matching circuit in accordance with an instruction which is received at a transmitter-receiver circuit through an antenna and is sent from the power receiving device.

23. The power feeding device according to claim 22,

wherein the matching circuit comprises a variable element.

24. A power feeding device comprising:

a first resonance coil configured to transmit power from a power source to a second resonance coil in a power receiving device;

a coil connected to the power source;

a matching circuit operationally connected to the first resonance coil; and

a control circuit configured to change an impedance of the matching circuit in accordance with an instruction which is received at a transmitter-receiver circuit through an antenna and is sent from the power receiving device,

wherein the coil is magnetically coupled with the first resonance coil.

25. The power feeding device according to claim 24,

wherein the matching circuit comprises a variable element.

26. The power feeding device according to claim 24,

wherein the coil is connected to the power source through the matching circuit.