WIRELESS POWER TRANSFER USING STACKED RESONATORS

• US 20160126744A1
• Filed: 10/30/2014
• Published: 05/05/2016
• Est. Priority Date: 10/30/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Jeong, Seong Heon, Carobolante, Francesco
• Granted Patent: US 10,128,663 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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,

said at least one secondary resonator being 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 so that a resultant magnetic field arises from interactions between said primary and secondary magnetic fields.

2. The apparatus of claim 1, wherein said at least one secondary resonator has a configuration and an arrangement relative to said primary coil 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 has a configuration and an arrangement relative to said primary coil 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 has a configuration and an arrangement relative to said primary coil 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, further comprising a tertiary resonator disposed on a third plane, wherein said tertiary resonator does not overlap with said primary resonator, said tertiary resonator configured to generate a tertiary magnetic field when coupled with said primary magnetic field generated by said primary resonator, wherein said resultant field is further a result of interactions among said primary, secondary, and tertiary magnetic fields.

8. The apparatus of claim 7, 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 and said at least one secondary resonator is disposed on a secondary substrate, said primary substrate and said secondary substrate being stacked.

10. The apparatus of claim 1, further comprising a tertiary resonator disposed on a third plane, said tertiary resonator in 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, an interaction between said primary magnetic field and said secondary 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, further comprising generating a tertiary magnetic field by aligning a tertiary resonator relative to said primary resonator so that said tertiary resonator does not overlap with said primary resonator, said primary, secondary, and tertiary magnetic fields interacting to produce said resultant magnetic field.

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

means for supporting said means for 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 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.