Wireless power transfer using stacked resonators

• US 10,128,663 B2
• Filed: 10/30/2014
• Issued: 11/13/2018
• Est. Priority Date: 10/30/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Jeong, Seong Heon, Carobolante, Francesco
• Primary Examiner(s): Chang, Joseph
• Application Number:
  US14/528,634
• Publication Number:
  US 20160126744A1
• Time in Patent Office: 1,475 Days
• Field of Search: 307104
• 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 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment

Abstract

A wireless power transfer system may include a primary resonator and one or more secondary resonators. At least one of the secondary resonators lie in overlapping relation to the primary resonator. An electromagnetic (EM) field generated by the primary resonator can couple to the secondary resonators, thus inducing current flow in the secondary resonators. EM fields generated by the secondary resonators interact with the EM field from the primary resonator to produce a resultant EM field.

Claims

1. An apparatus operative with a primary resonator substantially disposed on a first plane, said primary resonator coupled to a power source, said apparatus comprising:

at least one secondary resonator substantially disposed on a second plane and coextensive with at least a portion of said primary resonator,

at least one tertiary resonator disposed on a third plane, wherein the first plane, the second plane, and the third plane are different from one another,

said at least one secondary resonator and said at least one tertiary resonator being parasitic coils that are galvanically isolated from said primary resonator,

said at least one secondary resonator configured to generate a secondary magnetic field when coupled with a primary magnetic field generated by said primary resonator,

said at least one tertiary resonator configured to generate a tertiary magnetic field when coupled with said primary magnetic field generated by said primary resonator, wherein a resultant magnetic field arises from interactions between said primary, secondary and tertiary magnetic fields.

2. The apparatus of claim 1, wherein said at least one secondary resonator and said at least one tertiary resonator have a configuration and an arrangement relative to said primary resonator so that said resultant magnetic field has a field distribution more uniform than a magnetic field produced by said primary resonator alone.

3. The apparatus of claim 1, wherein said at least one secondary resonator and said at least one tertiary resonator have a configuration and an arrangement relative to said primary resonator so that said resultant magnetic field has a field distribution that is different in extent in comparison to a magnetic field produced by said primary resonator alone.

4. The apparatus of claim 1, wherein said at least one secondary resonator and said at least one tertiary resonator have a configuration and an arrangement relative to said primary resonator so that said resultant magnetic field has a field distribution having a maximum height different from that of a magnetic field produced by said primary resonator alone.

5. The apparatus of claim 1, wherein said at least one secondary resonator extends over at most only a portion of said primary resonator.

6. The apparatus of claim 1, wherein said primary resonator and said at least one secondary resonator define a periphery larger than a periphery of said primary resonator alone.

7. The apparatus of claim 1, wherein said tertiary resonator does not overlap with said primary resonator.

8. The apparatus of claim 1, wherein said tertiary resonator does not overlap with said at least one secondary resonator.

9. The apparatus of claim 1, wherein said primary resonator is disposed on a primary substrate, said at least one secondary resonator is disposed on a secondary substrate, said at least one tertiary resonator is disposed on a tertiary substrate, said primary substrate being disposed below said secondary substrate and said tertiary substrate.

10. The apparatus of claim 1, wherein said tertiary resonator is in an overlapping relation with said primary resonator and said at least one secondary resonator.

11. The apparatus of claim 1, wherein said at least one secondary resonator includes a capacitive element connected in series therewith.

12. The apparatus of claim 11, wherein said capacitive element is sized so that a resonant frequency said at least one secondary resonator is substantially the same as a resonant frequency of said primary resonator.

13. The apparatus of claim 11, wherein said capacitive element is sized so that a mutual coupling between said primary resonator and said at least one secondary resonator is substantially maximal.

14. A method of generating a magnetic field comprising:

coupling with a primary magnetic field generated by a primary resonator; and

generating a secondary magnetic field from coupling with said primary magnetic field by aligning a secondary resonator in overlapping relation with said primary resonator,

generating a tertiary magnetic field from coupling with said primary magnetic field by aligning a tertiary resonator in an overlapping relation with said primary resonator,

wherein said secondary resonator and said tertiary resonator are parasitic loops each disposed on different planes and an interaction between said primary magnetic field, said secondary magnetic field, and said tertiary magnetic field producing a resultant magnetic field having a field distribution different from said primary magnetic field.

15. The method of claim 14, wherein said field distribution of said resultant magnetic field is more uniform than a field distribution of said primary magnetic field alone.

16. The method of claim 14, wherein said field distribution of said resultant magnetic field is different in extent as compared to a field distribution of said primary magnetic field alone.

17. The method of claim 14, wherein said field distribution of said resultant magnetic field has a different maximum height as compared to a field distribution of said primary magnetic field alone.

18. The method of claim 14, wherein said secondary resonator overlaps at most only a portion of said primary resonator.

19. The method of claim 14, further comprising aligning said secondary resonator relative to said primary resonator so that a periphery defined by said primary and secondary resonators is larger than a periphery of said primary resonator alone.

20. The method of claim 14, wherein said tertiary resonator does not overlap with said primary resonator.

21. The method of claim 14, setting a resonant frequency of said secondary resonator substantially equal to a resonant frequency of said primary resonator.

22. An apparatus for generating a magnetic field comprising:

means for parasitically coupling with a primary magnetic field generated by a primary resonator, said means for parasitically coupling configured to generate a secondary magnetic field and a tertiary magnetic field from being coupled with said primary magnetic field, said means parasitically for coupling coextensive with said primary resonator such that interaction between said primary magnetic field, said secondary magnetic field, and said tertiary magnetic field produces a resultant magnetic field having a field distribution different from said primary magnetic field; and

means for supporting said means for parasitically coupling relative to said primary magnetic field.

23. The apparatus of claim 22, wherein said field distribution of said resultant magnetic field is more uniform than a field distribution of said primary magnetic field alone.

24. The apparatus of claim 22, wherein said field distribution of said resultant magnetic field is different in extent as compared to a field distribution of said primary magnetic field alone.

25. The apparatus of claim 22, wherein said field distribution of said resultant magnetic field has a different maximum height as compared to a field distribution of said primary magnetic field alone.

26. The apparatus of claim 22, wherein said means for parasitically coupling extends over at most only a portion of said primary resonator.

27. The apparatus of claim 22, wherein said primary resonator and said means for coupling define a periphery larger than a periphery of said primary resonator alone.