Wireless Energy Transfer with Negative Index Material

• US 20110156486A1
• Filed: 12/29/2009
• Published: 06/30/2011
• Est. Priority Date: 12/29/2009
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Inventors: Lyer, Vishwanath, Duan, Chunjie, Huang, Da, Yerazunis, William S., Teo, Koon Hoo
• Granted Patent: US 8,415,833 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves

Abstract

Embodiments of the invention disclose a method and a system configured to exchange energy wirelessly, comprising a structure configured to exchange the energy wirelessly via a coupling of evanescent waves, wherein the structure is electromagnetic (EM) and non-radiative, and wherein the structure generates an EM near-field in response to receiving the energy; and a controller configured to tune up the structure such that the near-field is generated according a particular energy distribution pattern.

Claims

1. A system configured to exchange energy wirelessly, comprising:

a structure configured to exchange the energy wirelessly via a coupling of evanescent waves, wherein the structure is electromagnetic (EM) and non-radiative, and wherein the structure generates an EM field in response to receiving the energy; and

a controller configured to tune a dominant frequency of the structure such that the near-field is generated according a particular energy distribution pattern.

2. The system of claim 1, wherein the structure is a source configured to transfer the energy to a sink, further comprising:

a driver configured to supply the energy to the structure.

3. The system of claim 1, wherein the structure is a sink configured to receive the energy wirelessly from a source, further comprising:

a load configured to receive the energy from the structure.

4. The system of claim 1, further comprising:

a negative index material (NIM) arranged within the EM field such that the coupling is enhanced.

5. The system of claim 1, wherein the structure is a resonant structure.

6. The system of claim 1, wherein the NIM is arranged optimally based on a desired direction of the energy transfer.

7. The system of claim 1, wherein the NIM is arranged such as to substantially enclose the structure.

8. The system of claim 1, wherein the particular energy distribution pattern is selected from a group of patterns that include an even butterfly pattern, an odd butterfly pattern, even crossing pattern, and an odd crossing pattern.

9. The system of claim 1, wherein the particular energy distribution pattern is determined based on an orientation between a source and a sink.

10. The system of claim 1, wherein the NIM has a negative permittivity property and a negative permeability property.

11. A method for exchanging energy wirelessly via a coupling of near-fields, comprising steps of:

providing a first structure configured to exchange an energy wirelessly with a second structure via the coupling of near-fields of the first structure and the second structure, wherein the first and the second structures are electromagnetic (EM) and non-radiative, and wherein the first and the second structures generate EM near-fields in response to receiving the energy;

determining an orientation between the first structure and the second structure;

tuning a dominant frequency of the first structure such that the near-field of the first structure is generated according a particular energy distribution pattern optimal for the orientation; and

exchanging energy wirelessly.

12. The method of clam 11, further comprising:

increasing the coupling with a negative index material (NIM) arranged within at least one EM near-field.

13. The method of clam 11 wherein the first structure is a resonant structure.

14. The method of clam 12, further comprising:

arranging the NIM is based on the orientation between the first structure and the second structure.

15. The method of clam 12, further comprising:

substantially enclosing the first structure with the NIM.

16. The method of clam 11, wherein the particular energy distribution pattern is selected from a group of patterns that includes an even butterfly pattern, an odd butterfly pattern, even crossing pattern, and an odd crossing pattern.

17. A system for exchanging energy wirelessly via a coupling of near-fields, comprising:

a first structure configured to exchange an energy wirelessly with a second structure via the coupling of near-fields of the first structure and the second structure, wherein the first and the second structures are electromagnetic (EM) and non-radiative, and wherein the first and the second structures generate EM near-fields in response to receiving the energy;

means for determining an orientation between the first structure and the second structure; and

means for tuning a dominant frequency of the first structure such that the near-field of the first structure is generated according a particular energy distribution pattern optimal for the orientation.

20. The system of claim 17, further comprising:

a negative index material (NIM) arranged within the EM near-field such that the coupling is enhanced.

18. The system of clam 17, wherein the particular energy distribution pattern is selected from a group of patterns that includes an even butterfly pattern, an odd butterfly pattern, even crossing pattern, and an odd crossing pattern.

19. The system of clam 17, wherein the particular energy distribution pattern is selected such as to optimize the exchange of the energy.