IP Library Granted Patent US 8,400,019
Granted Patent B2
US 8,400,019 · App. 12/639,966 · Granted Mar 19, 2013

Wireless energy transfer with high-Q from more than one source

Inventors: John D. Joannopoulos (Belmont, MA); Aristeidis Karalis (Boston, MA); Marin Soljacic (Belmont, MA)
Assignee: Massachusetts Institute of Technology
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 8,400,019
App. No.
12/639,966
Granted
Mar 19, 2013
Kind
B2
Abstract

Described herein are embodiments of a source high-Q resonator, optionally coupled to an energy source, a second source high-Q resonator, optionally coupled to an energy source, and a third high-Q resonator, optionally coupled to an energy drain, where at least one of the source resonators and the third resonator may be coupled to transfer electromagnetic energy from at least one of the said source resonators to said third resonator.

Claims (56)

1. A system, comprising:

a source high-Q resonator, configured to be coupled to an energy source, the source high-Q resonator having a resonant frequency ω 1 and an intrinsic loss rate Γ 1 , and capable of storing electromagnetic energy with a high intrinsic quality factor Q 1 =ω 1 /(2Γ 1 ):

a second source high-Q resonator, configured to be coupled to an energy source, the second source high-Q resonator having a resonant frequency ω 2 and an intrinsic loss rate Γ 2 , and capable of storing electromagnetic energy with a high intrinsic quality factor Q 2 =ω 2 /(2Γ 2 ); and

a third high-Q resonator, the third high-Q resonator having a resonant frequency ω 3 and an intrinsic loss rate Γ 3 , and capable of storing electromagnetic energy with a high intrinsic quality factor Q 3 =ω 3 /(2Γ 3 ),

wherein at least one of the source resonators and the third resonator are configured to be coupled to transfer electromagnetic energy from at least one of the said source resonators to said third resonator via wireless near-field energy transfer.

2. The system of claim 1 , further comprising the first mentioned energy source coupled to the first-mentioned source resonator and the second-mentioned energy source coupled to the second source resonator.

3. The system of claim 1 , further comprising an energy drain coupled to the third resonator.

4. The system of claim 3 , wherein the energy drain comprises a robot, vehicle, computer, cell phone, or a portable electronic device.

5. The system of claim 1 , wherein at least one of Q 1 , Q 2 , and Q 3 is greater than 100.

6. The system of claim 5 , wherein another of Q 1 , Q 2 , and Q 3 is greater than 100.

7. The system of claim 1 , wherein third resonator is electromagnetically coupled to at least one of the source resonators.

8. The system of claim 7 , wherein the source resonators are each configured to wirelessly transfer electromagnetic energy to the third resonator.

9. The system of claim 7 , wherein at least one of Q 1 , Q 2 , and Q 3 is greater than 100.

10. The system of claim 9 , wherein another of Q 1 , Q 2 , and Q 3 is greater than 100.

11. The system of claim 1 , wherein at least one of the resonators is tunable.

12. The system of claim 1 , wherein the third resonator is movable relative to the source resonators and wherein the wireless energy transfer occurs over a range of distances.

13. The system of claim 12 , wherein the range of distances includes 5 cm.

14. The system of claim 12 , wherein the range of distances includes 10 cm.

15. The system of claim 12 , wherein the range of distances includes 30 cm.

16. The system of claim 12 , wherein κ/√{square root over (Γ 1 Γ 2 )}>0.2 over the range of distances, wherein κ is the wireless energy transfer rate, Γ 1 is the intrinsic loss rate of said at least one of the source resonators, and Γ 2 is the intrinsic loss rate of the third resonator.

17. The system of claim 16 , wherein κ/√{square root over (Γ 1 Γ 2 )}>0.5 over the range of distances.

18. The system of claim 16 , wherein κ/√{square root over (Γ 1 Γ 2 )}>1 over the range of distances.

19. The system of claim 12 , wherein the efficiency of the wireless energy transfer is at least 20% over the range of distances.

20. The system of claim 1 , wherein the resonant frequencies f 1 =ω 1 /2π, f 2 =ω 2 /2π, and f 3 =ω 3 /2π of the resonators are each at least 5 MHz.

21. The system of claim 1 , further comprising a feedback mechanism coupled to at least one of the resonators to correct for detuning.

22. The system of claim 1 , wherein the first-mentioned energy source is coupled to the first-mentioned source resonator, an energy drain is coupled to the third resonator, and the first-mentioned source resonator is electromagnetically coupled to the third resonator, and wherein the first-mentioned energy source and energy drain are configured to be driven to increase the ratio of useful-to-lost power for varying wireless energy transfer rates κ between the first-mentioned source resonator and the third resonator.

23. The system of claim 1 , wherein the first-mentioned source resonator is electromagnetically coupled to the third resonator, and wherein the first-mentioned source resonator and third resonator are configured to be adjustably tuned to increase the ratio of useful-to-lost power for varying wireless energy transfer rates κ between the first-mentioned source resonator and the third resonator.

24. The system of claim 1 , wherein the source resonator and the third resonator have different characteristic sizes.

25. A method, comprising:

providing a source high-Q resonator, configured to be coupled to an energy source, the source high-Q resonator having a resonant frequency ω 1 and an intrinsic loss rate Γ 1 , and capable of storing electromagnetic energy with a high intrinsic quality factor Q 1 =ω 1 /(2Γ 1 );

providing a second source high-Q resonator, configured to be coupled to an energy source, the second source high-Q resonator having a resonant frequency ω 2 and an intrinsic loss rate Γ 2 , and capable of storing electromagnetic energy with a high intrinsic quality factor Q 2 =ω 2 /(2Γ 2 ); and

providing a third high-Q resonator, the third high-Q resonator having a resonant frequency ω 3 and an intrinsic loss rate Γ 3 , and capable of storing electromagnetic energy with a high intrinsic quality factor Q 3 =ω 3 /(2Γ 3 ),

wherein at least one of the source resonators and the third resonator are configured to be coupled to transfer electromagnetic energy from at least one of the said source resonators to said third resonator via wireless near-field energy transfer.

26. The method of claim 25 , wherein the first-mentioned energy source is coupled to the first-mentioned source resonator.

27. The method of claim 25 , wherein an energy drain is coupled to the third resonator.

28. The method of claim 27 , wherein the energy drain comprises a robot, vehicle, computer, cell phone, or a portable electronic device.

29. The method of claim 25 , wherein at least one of Q 1 , Q 2 , and Q 3 is greater than 100.

30. The method of claim 29 , wherein another of Q 1 , Q 2 , and Q 3 is greater than 100.

31. The method of claim 25 , wherein the third resonator is electromagnetically coupled to at least one of the source resonators.

32. The method of claim 31 , wherein each of the source resonators is configured to wirelessly transfer electromagnetic energy to the third resonator.

33. The method of claim 31 , wherein at least one of Q 1 , Q 2 , and Q 3 is greater than 100.

34. The method of claim 31 , wherein another of Q 1 , Q 2 , and Q 3 is greater than 100.

35. The method of claim 25 , wherein at least one of the resonators is tunable.

36. The method of claim 25 , wherein the third resonator is movable relative to each of the source resonators and wherein the wireless energy transfer occurs over a range of distances.

37. The method of claim 36 , wherein the range of distances includes 5 cm.

38. The method of claim 36 , wherein the range of distances includes 10 cm.

39. The method of claim 36 , wherein the range of distances includes 30 cm.

40. The method of claim 36 , wherein κ/√{square root over (Γ 1 Γ 2 )}>0.2 over the range of distances, wherein κ is the wireless energy transfer rate, Γ 1 is the intrinsic loss rate of said at least one of the source resonators, and Γ 2 is the intrinsic loss rate of the third resonator.

41. The method of claim 40 , wherein κ/√{square root over (Γ 1 Γ 2 )}>0.5 over the range of distances.

42. The method of claim 40 , wherein κ/√{square root over (Γ 1 Γ 2 )}>1 over the range of distances.

43. The method of claim 36 , wherein the efficiency of the wireless energy transfer is at least 20% over the range of distances.

44. The method of claim 25 , wherein the resonant frequencies f 1 =ω 1 /2π, f 2 =ω 2 /2π, and f 3 =ω 3 /2π of the resonators are each at least 5 MHz.

45. The method of claim 25 , wherein a feedback mechanism is coupled to at least one of the resonators to correct for detuning.

46. The method of claim 25 , wherein the energy source is coupled to the first-mentioned source resonator, an energy drain is coupled to the third resonator, and the first-mentioned source resonator is electromagnetically coupled to the third resonator, and wherein the first-mentioned energy source and energy drain is driven to increase the ratio of useful-to-lost power for varying wireless energy transfer rates κ between the first-mentioned source resonator and the third resonator.

47. The method of claim 25 , wherein the first-mentioned source resonator is electromagnetically coupled to the third resonator, and wherein the first-mentioned source resonator and third resonator are adjustably tuned to increase the ratio of useful-to-lost power for varying wireless energy transfer rates κ between the first-mentioned source resonator and the third resonator.

48. The method of claim 25 , wherein the source resonator and the third resonator have different characteristic sizes.

Assignments (3)
CONFIRMATORY LICENSE Recorded Apr 15, 2015
From: MASSACHUSETTS INSITUTE OF TECHNOLOGY
To: NATIONAL SCIENCE FOUNDATION
Reel/Frame 035413/0840 →
LICENSE Recorded Feb 10, 2012
From: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
To: WITRICITY CORPORATION
Reel/Frame 027689/0003 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 22, 2010
From: JOANNOPOULOS, JOHN D.; KARALIS, ARISTEIDIS; SOLJACIC, MARIN
To: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
Reel/Frame 024271/0854 →
Continuity (4)
Continuation 12553957 · Sep 3, 2009
Continuation 11481077 · Jul 5, 2006
Provisional Application 60698442 · Jul 12, 2005
Related Publication 20100123353A1 · May 20, 2010