Wireless energy transfer system

• US 8,421,274 B2
• Filed: 09/10/2009
• Issued: 04/16/2013
• Est. Priority Date: 09/12/2008
• Status: Active Grant

• Current Assignee: University of Pittsburgh of The Commonwealth System of Higher Education
• Original Assignee: University of Pittsburgh of The Commonwealth System of Higher Education
• Inventors: Sun, Mingui, Hackworth, Steven, Sclabassi, Robert, Zhang, Fei, Liu, Xiaoyu
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): VU, TOAN T
• Application Number:
  US12/556,828
• Publication Number:
  US 20110101788A1
• Time in Patent Office: 1,314 Days
• Field of Search: 307/104, 336/198, 336/206, 336/219
• 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 50/005 Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• 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: H04B 5/266 One coil at each side, e.g. with primary and secondary coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

A wireless energy transfer system includes a first energy transfer unit having at least one resonant frequency, a second energy transfer unit having the at least one resonant frequency, and a load. The first wireless energy transfer unit includes a first coil magnetically coupled to a first wireless energy transfer cell, and the second wireless energy transfer unit includes a second coil magnetically coupled to a second wireless energy transfer cell. The first coil receives first energy and through the magnetic coupling between the first coil and the first wireless energy transfer cell, the first wireless energy transfer cell is caused to generate second energy, wherein the second wireless energy transfer cell receives the second energy and through the magnetic coupling between the second wireless energy transfer cell and the second coil, the second coil is caused to provide third electromagnetic wave energy to the load.

Claims

1. A wireless energy transfer unit having at least one resonant frequency, comprising:

an energy coupling/extraction coil; and

a wireless energy transfer cell magnetically coupled to said energy coupling/extraction coil, said wireless energy transfer cell comprising an LC resonant tank including at least one insulator having a first surface and a second surface opposite said first surface, a spiral conductor coil provided on said first surface of said at least one insulator, and a plurality of non-spiral conductive strips provided, on said second surface of said at least one insulator, wherein said spiral conductor coil, said at least one insulator and said plurality of non-spiral conductive strips form at least one capacitor of said LC resonant tank.

2. The wireless energy transfer unit according to claim 1, wherein said energy coupling/extraction coil comprises a single loop coil.

3. The wireless energy transfer unit according to claim 1, wherein said energy coupling/extraction coil comprises a plurality of loops.

4. The wireless energy transfer unit according to claim 1, wherein each of said non-spiral conductive strips overlaps a plurality of turns of said spiral conductor coil.

5. The wireless energy transfer unit according to claim 4, wherein said at least one insulator is a cylindrical insulator, wherein said conductor coil is a helical conductor coil.

6. The wireless energy transfer unit according to claim 5, wherein each of said conductive strips covers only two adjacent portions of said helical conductor coil.

7. The wireless energy transfer unit according to claim 1, wherein said at least one insulator is a flat insulator, wherein said spiral conductor coil is a flat conductor coil and wherein each of said plurality of non-spiral conductive strips is a flat conductive strip.

8. The wireless energy transfer unit according to claim 7, wherein said spiral conductor coil is a square spiral.

9. The wireless energy transfer unit according to claim 7, wherein said spiral conductor coil is a circular spiral.

10. The wireless energy transfer unit according to claim 7, wherein said conductor coil includes a plurality of crisscrossing portions along a length thereof such that a beginning and an end of the conductor coil are positioned adjacent to one another.

11. The wireless energy transfer unit according to claim 5, wherein said conductor coil includes a plurality of crisscrossing portions along a length thereof such that a beginning and an end of the conductor coil are positioned adjacent to one another.

12. A wireless energy transfer unit having at least one resonant frequency, comprising:

an energy coupling/extraction conductor; and

a multi-layer wireless energy transfer cell magnetically coupled to said energy coupling/extraction conductor, said multi-layer wireless energy transfer cell comprising;

a top layer and a bottom layer, said top layer and said bottom layer being made of a magneto-electric material that produces an electric field when exposed to a magnetic field;

a first conductor layer forming a first electrode positioned adjacent to said top layer;

a second conductor layer forming a second electrode positioned adjacent to said bottom layer; and

a central layer positioned between said first conductor layer and said second conductor layer, said central layer being made of a piezoelectric material which resonates in response to an electric field being applied thereto by said first conductor layer and said second conductor layer.

13. A wireless energy transfer unit having at least one resonant frequency, comprising:

an energy coupling/extraction conductor; and

a multi-layer wireless energy transfer cell magnetically coupled to said energy coupling/extraction conductor, said multi-layer wireless energy transfer cell comprising;

a first coil element including a first insulator layer and a first conductor coil provided on said first insulator layer, said first conductor coil including a plurality of first crisscrossing portions along a length thereof such that a first beginning and a first end of said first conductor coil are positioned adjacent to one another;

a second coil element including a second insulator layer and a second conductor coil provided on said second insulator layer, said second conductor coil including a plurality of second crisscrossing portions along a length thereof such that a second beginning and a second end of said second conductor coil are positioned adjacent to one another; and

an insulator element made of an insulating material provided between said first coil element and said second coil element;

wherein said first coil element and said second coil element are electrically connected to one another.

14. The wireless energy transfer unit according to claim 13, wherein said first coil element and said second coil element are electrically connected to one another through said insulator element.

15. The wireless energy transfer unit according to claim 14, wherein said first beginning of said first coil element is electrically connected to said second end of said second coil element.

16. The wireless energy transfer unit according to claim 13, wherein said multi-layer wireless energy transfer cell further comprises:

a third coil element including a third insulator layer and a third conductor provided on said third insulator layer, said third conductor coil including a plurality of third crisscrossing portions along a length thereof such that a third beginning and a third end of said third conductor coil are positioned adjacent to one another; and

a second insulator element made of an insulating material provided between said second coil element and said third coil element;

wherein said second coil element and said third coil element are electrically connected to one another.

17. The wireless energy transfer unit according to claim 16, wherein said first coil element and said second coil element are electrically connected to one another through said insulator element and said second coil element and said third coil element are electrically connected to one another through said second insulator element.

18. The wireless energy transfer unit according to claim 17, wherein said first beginning of said first coil element is electrically connected to said second end of said second coil element, and said second beginning of said second coil element is electrically connected to said third end of said third coil element.

19. The wireless energy transfer unit according to claim 13, wherein said first coil element, said second coil element and said insulator element are disk-shaped.

20. The wireless energy transfer unit according to claim 16, wherein said first coil element, said second coil element, said third coil element, said insulator element, and said second insulator element are disk-shaped.

21. The wireless energy transfer unit according to claim 13, wherein said first conductor coil and said second conductor coil are each film coils.

22. The wireless energy transfer unit according to claim 13, wherein said first conductor coil, said second conductor coil and said third conductor coil are each film coils.

23. A wireless energy transfer unit having at least one resonant frequency, comprising:

an energy coupling/extraction conductor; and

a multi-layer cylindrical wireless energy transfer cell magnetically coupled to said energy coupling/extraction conductor, said multi-layer cylindrical wireless energy transfer cell comprising;

an inner cylindrical insulator;

a first spiral conductor coil provided on a surface of said inner cylindrical insulator;

an insulator layer provided on top of said first spiral conductor coil; and

a second spiral conductor coil provided on a surface of said insulator layer, said second spiral conductor coil being electrically connected to said first spiral conductor coil.

24. The wireless energy transfer unit according to claim 23, wherein said first spiral conductor coil is oriented in one of a positive angle and a negative angle with respect to a longitudinal axis of said inner cylindrical insulator, and wherein said second spiral conductor coil is oriented in the other of said positive angle and said negative angle with respect to said longitudinal axis of said inner cylindrical insulator.

25. The wireless energy transfer unit according to claim 24, wherein said first spiral conductor coil includes a plurality of first enlarged portions along a length thereof, wherein said second spiral conductor coil includes a plurality of second enlarged portions along a length thereof, and wherein each of said second enlarged portions corresponds to and overlaps a respective one of said first enlarged portions.

26. The wireless enemy transfer unit according to claim 25, wherein each of said first enlarged portions and each of said second enlarged portions is disk-shaped.

27. The wireless energy transfer unit according to claim 23, wherein said multi-layer cylindrical wireless energy transfer cell further comprises a ferrite core provided inside said inner cylindrical insulator.