Wireless power feeding system and wireless power feeding method

• US 9,641,027 B2
• Filed: 05/25/2012
• Issued: 05/02/2017
• Est. Priority Date: 09/21/2011
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Tsuji, Masayoshi, Hattori, Wataru, Tanomura, Masahiro, Yoshida, Shuhei
• Primary Examiner(s): Kaplan, Hal
• Assistant Examiner(s): Vu, Toan
• Application Number:
  US14/345,602
• Publication Number:
  US 20140339913A1
• Time in Patent Office: 1,803 Days
• Field of Search: 307104
• CPC Class Codes: B60L 50/60 using power supplied by batteries in combination with fuel cells B60L50/75
• CPC Class Codes: B60M 7/00 Power lines or rails specially adapted for electrically-propelled vehicles of special types, e.g. suspension tramway, ropeway, underground railway
• 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 50/05 using capacitive coupling
• 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: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A wireless power feeding system capable of long distance and highly efficient space transmission of power is provided. A wireless power feeding system includes a power transmitter, a power receiver, and a power receiving body. The power transmitter generates electromagnetic waves. The power receiver is supplied with power by means of the electromagnetic waves received from the power transmitter using a magnetic field resonance phenomenon. The power receiving body is inserted into an electromagnetic field created by the power transmitter and the power receiver, and receives power by means of the electromagnetic field.

Claims

1. A wireless power feeding system comprising:

a power transmitter that generates electromagnetic waves;

a power receiver that is supplied with power by means of the electromagnetic waves received from the power transmitter using an electric field or magnetic field resonance phenomenon; and

a power receiving body that receives power transmitted between the power transmitter and the power receiver by electromagnetic induction, wherein

a resonant frequency of the power receiving body is different from resonant frequencies of the power transmitter and the power receiver.

2. The wireless power feeding system according to claim 1, wherein the power receiver receives power from the electromagnetic field by means of electromagnetic induction.

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

a feedback loop that connects the power receiver and the power transmitter and feeds the power received by the power receiver back to the power transmitter.

4. The wireless power feeding system according to claim 1, wherein the power transmitter and the power receiver have the same resonant frequency.

5. The wireless power feeding system according to claim 1, wherein

the power transmitter includes at least one transmitter coil, and

the power receiver includes at least one receiver coil.

6. The wireless power feeding system according to claim 5, wherein

the power transmitter includes a plurality of transmitter coils mounted side by side on the same plane, and

the power receiver includes a plurality of receiver coils mounted side by side on the same plane.

7. The wireless power feeding system according to claim 6, wherein the electromagnetic waves transmitted from the plurality of transmitter coils have different phases from one another.

8. The wireless power feeding system according to claim 5, wherein the power transmitter and the power receiver are mounted facing each other at a specified distance.

9. The wireless power feeding system according to claim 5, wherein the power transmitter and the power receiver are mounted side by side on the same plane.

10. The wireless power feeding system according to claim 1, further comprising:

a repeater coil inserted between the power transmitter and the power receiver.

11. The wireless power feeding system according to claim 10, wherein the repeater coil is mounted on a plane perpendicular to a magnetic field line between the power transmitter and the power receiver.

12. The wireless power feeding system according to claim 10, wherein the repeater coil is electrically floating.

13. The wireless power feeding system according to claim 1, wherein the power receiving body includes at least one receiving coil.

14. The wireless power feeding system according to claim 1, wherein the power receiving body is configured as a power receiving unit that can be incorporated into another equipment and supplies power to the equipment.

15. The wireless power feeding system according to claim 1, wherein

a plurality of power receiving bodies are inserted into the electromagnetic field created between the power transmitter and the power receiver.

16. The wireless power feeding system according to claim 1, further comprising:

a closed structure placed between the power transmitter and the power receiver, wherein

a plurality of power receiving bodies are inserted inside the closed structure.

17. The wireless power feeding system according to claim 15, wherein the plurality of power receiving bodies receive power supply at a same time.

19. The wireless power feeding system according to claim 1, wherein the power transmitter further comprises:

a power supply device;

a transmitter primary coil that is connected with the power supply device; and

a transmitter secondary coil that is electrically isolated from the transmitter primary coil.

20. The wireless power feeding system according to claim 1, wherein

the power receiver further comprises:

a receiver secondary coil; and

a receiver primary coil that is electrically isolated from the receiver secondary coil.

18. A wireless power feeding method comprising:

creating an electromagnetic field between a power transmitter and a power receiver using an electric field or magnetic field resonance phenomenon; and

causing the power receiving body to receive power transmitted between the power transmitter and the power receiver by electromagnetic induction, wherein

a resonant frequency of the power receiving body is different from resonant frequencies of the power transmitter and the power receiver.