Wireless energy transfer resonator thermal management

• US 8,947,186 B2
• Filed: 02/07/2011
• Issued: 02/03/2015
• Est. Priority Date: 09/27/2008
• Status: Active Grant

• Current Assignee: WiTricity Corporation
• Original Assignee: WiTricity Corporation
• Inventors: Kurs, Andre B., Kesler, Morris P., Hall, Katherine L., Fiorello, Ron, MacDonald, Matthew J.
• Primary Examiner(s): Chan, Tsz
• Application Number:
  US13/021,965
• Publication Number:
  US 20110121920A1
• Time in Patent Office: 1,457 Days
• Field of Search: 336/55, 336/178, 336/212, 336/213
• US Class Current: 336/55
• CPC Class Codes: H01F 27/22 Cooling by heat conduction through solid or powdered fillings
• 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 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H03H 7/40 Automatic matching of load impedance to source impedance
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making
• CPC Class Codes: Y10T 29/4935 Heat exchanger or boiler making

Abstract

Described herein are improved configurations for a wireless power transfer. Described are methods and designs to reduce and manage heating and heat dissipation in resonator structures. Configuration and orientation of magnetic material as well as heat sinking material with respect to the dipole moment of the resonator is used to reduce and control thermal properties of the resonator structure and reduce the effects of heating on the performance of wireless power transfer.

Claims

1. A resonator structure for wireless power transfer comprising:

a block of magnetic material;

an electrical conductor, wrapped around at least a portion of an outer surface of the block of magnetic material and forming a plurality of loops that do not extend through the magnetic material and are substantially aligned around an axis;

a block of a thermal conductor, wherein the block of the thermal conductor is positioned in contact with the block of magnetic material and between two of the loops of the electrical conductor; and

one or more adjustable circuit elements coupled to the electrical conductor and configured so that during operation, an electrical impedance of the resonator structure can be varied by adjusting the one or more circuit elements.

2. The structure of claim 1, wherein the block of magnetic material comprises a plurality of smaller tiles of magnetic material.

3. The structure of claim 2, wherein the plurality of smaller tiles of magnetic material are arranged to minimize a number of tile seams that are oriented substantially perpendicular to the axis of the conductor loops.

4. The structure of claim 3, wherein the plurality of smaller tiles of magnetic material each have substantially regular edges that form substantially regular seams between the tiles.

5. The structure of claim 3, wherein the plurality of smaller tiles of the magnetic material are positioned to form seams that span gaps between adjacent tiles, and wherein only the seams perpendicular to the axis of the conductor loops correspond to substantially uniform gaps.

6. The structure of claim 2, further comprising multiple blocks of the thermal conductor positioned over seams formed between adjacent ones of the plurality of tiles of the magnetic material.

7. The structure of claim 6, wherein the conductor is positioned over seams that are oriented perpendicular to the axis of the conductor loops.

8. The structure of claim 6, wherein at least some of the multiple blocks of the thermal conductor comprise elongated strips of the thermal conductor positioned so that an elongate axis of each strip is oriented substantially perpendicular to the axis of the conductor loops.

9. The structure of claim 6, wherein at least some of the multiple blocks of the thermal conductor are coupled to a heat sink.

10. The structure of claim 1, wherein the thermal conductor is an electrical conductor.

11. The structure of claim 10, wherein the block of the thermal conductor is electrically isolated from the block of magnetic material.

12. The structure of claim 8, wherein the elongated strips of the thermal conductor are hollow elongated strips comprising a hollow cavity.

13. The structure of claim 12, wherein the elongated strips are positioned so that during operation of the resonator structure, a coolant can be directed to flow through the hollow cavity.

14. The structure of claim 6, wherein the multiple blocks of the thermal conductor are positioned in contact with a center of the block of magnetic material.

15. The structure of claim 6, wherein the multiple blocks of the thermal conductor are positioned in contact with the magnetic material and separated from one another by less than 4 centimeters.

16. The structure of claim 1, wherein two or more conductors are each wrapped around at least a portion of an outer surface of the block of magnetic material and each form a plurality of loops that do not extend through the magnetic material.

17. The structure of claim 16, further comprising multiple blocks of the thermal conductor, wherein each plurality of loops bounds a portion of a surface area of the magnetic material, and wherein within each bounded portion of the surface area, at least one of the multiple blocks of the thermal conductor contacts the magnetic material.