WIRELESS POWER FEEDER, WIRELESS POWER RECEIVER, AND WIRELESS POWER TRANSMISSION SYSTEM, AND COIL

• US 20120223586A1
• Filed: 08/15/2011
• Published: 09/06/2012
• Est. Priority Date: 03/01/2011
• Status: Active Grant

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: GOTANI, Akira
• Granted Patent: US 8,922,064 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 50/50 using additional energy repeaters between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment

Abstract

A wireless power feeder feeds power from a feeding coil to a receiving coil by wireless using a magnetic field resonance phenomenon. The feeding coil is constructed in a rotatable manner. A power transmission control circuit that supplies AC power to the feeding coil so as to make the feeding coil feed the AC power to the receiving coil. The feeding coil is constructed such that the magnetic characteristics thereof in the circumferential direction are made non-uniform. Concretely, a magnetic body is installed at only a part of the circumference of the feeding coil to make the magnetic characteristics of the feeding coil in the circumferential direction non-uniform.

Claims

1. A wireless power feeder that feeds power from a feeding coil to a receiving coil by wireless using a magnetic field resonance phenomenon between the feeding coil and receiving coil, said feeder comprising:

the feeding coil constructed in a rotatable manner; and

a power transmission control circuit that supplies AC power to the feeding coil so as to make the feeding coil feed the AC power to the receiving coil,

the feeding coil being constructed such that the magnetic characteristics thereof in the circumferential direction are made non-uniform.

2. The wireless power feeder according to claim 1, wherein

a magnetic body is installed at only a part of the circumference of the feeding coil to make the magnetic characteristics of the feeding coil in the circumferential direction non-uniform.

3. The wireless power feeder according to claim 1, wherein

the power transmission control circuit rotates the feeding coil so as to control the AC power to be fed from the feeding coil to the receiving coil.

4. A wireless power receiver that receives, at a receiving coil, AC power fed from a feeding coil by wireless using a magnetic field resonance phenomenon between the feeding coil and receiving coil, said receiver comprising:

the receiving coil constructed in a rotatable manner; and

a loading circuit including a loading coil that is magnetically coupled to the receiving coil to receive the AC power from the receiving coil and a load that receives the AC power from the loading coil,

the receiving coil being constructed such that the magnetic characteristics thereof in the circumferential direction thereof are made non-uniform.

5. The wireless power receiver according to claim 4, wherein

a magnetic body is installed at only a part of the circumference of the receiving coil to make the magnetic characteristics of the receiving coil in the circumferential direction non-uniform.

6. The wireless power receiver according to claim 4, further comprising a power receiving control circuit that rotates the receiving coil so as to control the AC power received by the receiving coil.

7. A wireless power transmission system for feeding power by wireless from a feeding coil to a receiving coil using a magnetic field resonance phenomenon between the feeding coil and receiving coil, said system comprising:

a wireless power feeder and a wireless power receiver,

the wireless power feeder including;

the feeding coil; and

a power transmission control circuit that supplies AC power to the feeding coil so as to make the feeding coil feed the AC power to the receiving coil,

the wireless power receiver including;

the receiving coil; and

a loading circuit including a loading coil that is magnetically coupled to the receiving coil to receive the AC power from the receiving coil and a load that receives the AC power from the loading coil, and

both or one of the feeding and receiving coils being constructed in a rotatable manner and constructed as a non-uniform type coil in which the magnetic characteristics thereof in the circumferential direction are non-uniform.

8. The wireless power transmission system according to claim 7, wherein

at least the receiving coil is constructed as the non-uniform type coil, and

the wireless power receiver further includes a power receiving control circuit that rotates the receiving coil so as to control the AC power received by the receiving coil.

9. The wireless power transmission system according to claim 7, wherein

at least the feeding coil is constructed as the non-uniform type coil, and

the power transmission control circuit rotates the feeding coil so as to control the AC power to be fed from the feeding coil to the receiving coil.

10. The wireless power transmission system according to claim 7, wherein

a plurality of the wireless power receivers are provided for one wireless power feeder, and

AC power supplied from one feeding coil is received by one or more receiving coils.

11. A coil constructed such that the magnetic characteristics thereof in the circumferential direction are made non-uniform.

12. The coil according to claim 11, wherein

a magnetic body is installed at only a part of the circumference of the coil to make the magnetic characteristics of the coil in the circumferential direction non-uniform.

13. The coil according to claim 12, wherein

a circular arc magnetic body is installed along the inner side or outer side of the coil circumference to make the magnetic characteristics of the coil in the circumferential direction non-uniform.