Contactless power transfer system and method

• US 9,312,063 B2
• Filed: 01/28/2014
• Issued: 04/12/2016
• Est. Priority Date: 03/25/2010
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Bohori, Adnan Kutubuddin, Bray, James William, Ramachandrapanicker, Somakumar, Bhat, Suma Memana Narayana
• Primary Examiner(s): Tran, Thienvu
• Assistant Examiner(s): VU, TOAN T
• Application Number:
  US14/165,949
• Publication Number:
  US 20140139041A1
• Time in Patent Office: 805 Days
• Field of Search: 307/104
• US Class Current: 1/1
• CPC Class Codes: H01F 27/42 Circuits specially adapted for the purpose of modifying, or compensating for, electric characteristics of transformers, reactors, or choke coils circuits for controlling transformers, reactors or choke coils, for the purpose of obtaining a desired output H02P13/00; impedance networks H03H
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H01F 38/18 Rotary transformers
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas

Abstract

A contactless power transfer system is provided. The system includes a first coil configured to produce a magnetic field. The system also includes a second coil configured to receive power from the first coil via the magnetic field. The system further includes a field focusing element. The field focusing element includes a plurality of resonators arranged in an array. Each of the plurality of resonators, upon excitation, interfere constructively in a direction of the second coil and interfere destructively in a remaining space to focus the magnetic field onto the second coil and enhance the coupling between the first coil and the second coil.

Claims

1. A contactless power transfer system comprising:

a first coil configured to produce a magnetic field;

a second coil configured to receive power from the first coil via the magnetic field; and

a field focusing element comprising a plurality of resonators arranged in an array, wherein each of the plurality of resonators, upon excitation, interfere constructively in a direction of the second coil and interfere destructively in a remaining space to focus the magnetic field onto the second coil and enhance the coupling between the first coil and the second coil.

2. The contactless power transfer system of claim 1, further comprising two or more second coils configured to receive power from the first coil.

3. The contactless power transfer system of claim 1, wherein the first coil is coupled to a power source and the second coil is coupled to a power load.

4. The contactless power transfer system of claim 1, wherein the plurality of resonators is excited at different phases to focus the magnetic field on to the second coil.

5. The contactless power transfer system of claim 4, wherein a total magnetic field focused on to the second coil is a vector addition of the magnetic fields of the plurality of resonators excited at different phases.

6. The contactless power transfer system of claim 1, wherein the plurality of resonators is configured to operate at two or more unique resonant frequencies simultaneously.

7. The contactless power transfer system of claim 6, wherein the two or more unique resonant frequencies are configured to simultaneously transfer power and data signals.

8. The contactless power transfer system of claim 1, wherein the plurality of resonators are configured to operate at two or more unique resonant frequencies for bi-directionally transferring power, data and a combination thereof simultaneously.

9. The contactless power transfer system of claim 1, wherein the plurality of resonators are disposed within at least one of a dielectric medium, a magnetic medium, or a magneto-dielectric medium.

10. The contactless power transfer system of claim 1, wherein at least one of the first coil, the second coil, or the field focusing element is configured to rotate with respect to each other along an axis of rotation.

11. The contactless power transfer system of claim 10, wherein the field focusing element is further configured to focus the magnetic field along the axis of rotation.

12. A contactless power transfer system comprising:

a field focusing element comprising a plurality of resonators arranged in an array, wherein the array comprises an active array configuration, a passive array configuration or a combination thereof and the plurality of resonators interfere constructively in a desired direction and interfere destructively in a remaining space to focus a magnetic field based on the configuration of the array.

13. The field focusing element of claim 12, wherein the array comprises a linear, planar, circular or a three-dimensional array.

14. The field focusing element of claim 12, wherein the array comprises one or more sets of resonators.

15. The field focusing element of claim 14, wherein the one or more sets of resonators in the array are excited at different phases in a predetermined phase relationship to focus the magnetic field in the desired direction.

16. The field focusing element of claim 12, wherein a total field of the array comprises a vector addition of magnetic fields of the plurality of resonators in the array.

17. The field focusing element of claim 12, wherein amplitude and a phase of excitation of each of the plurality of resonators is controlled in the active array to focus the magnetic field in the desired direction.

18. The field focusing element of claim 12, wherein the passive array comprises one or more resonators electromagnetically coupled to at least one resonator excited by a first coil to generate an elongated magnetic field focusing beam for transferring power.

19. The field focusing element of claim 12, wherein the array comprises spatially disposed sub-wavelength resonators to form a passive structure wherein the passive structure results in effective negative permeability.