Adaptive matching and tuning of HF wireless power transmit antenna
View Patent ↗Exemplary embodiments of the invention s are directed to a wireless power system with different coupling loops, such as two loops. The coupling loops are switched. One can be used for vicinity coupling, e.g., greater than a distance away, the other for proximity coupling, e.g., less than a distance away.
1. A transmitter system for wireless power, comprising:
an antenna resonant at a first frequency; and
a coupling loop assembly comprising:
a first coupling loop;
a first switch configured to activate said first coupling loop;
a second coupling loop; and
a second switch configured to activate said second coupling loop, the coupling loop assembly configured to couple with said antenna via magnetic induction.
2. A system as in claim 1 , further comprising a controller configured to detect a coupling to the antenna, and to select either said first coupling loop or said second coupling loop based on said coupling.
3. A system as in claim 2 , wherein said controller is configured to detect proximity coupling and to select said first coupling loop upon detecting proximity coupling.
4. A system as in claim 2 , wherein said controller is configured to detect vicinity coupling and to select said second coupling loop upon detecting vicinity coupling.
5. A system as in claim 2 , wherein said antenna includes multiple loops.
6. A system as in claim 5 , further comprising a mechanism configured to adjust the position of said multiple loops relative to one another.
7. A system as in claim 2 , wherein said coupling loop assembly is unconnected to said antenna.
8. A system as in claim 1 , wherein said coupling loops are formed on a printed circuit board.
9. A system as in claim 1 , wherein said antenna comprises multiple loops.
10. A system as in claim 9 , further comprising a mechanism configured to adjust the position of said multiple loops relative to one another.
11. A transmitter system as in claim 1 , further comprising a first circuit coupled to said antenna, and configured to cause production of a signal at the first frequency.
12. A system as in claim 1 , further comprising a mechanism configured to adjust the position of said coupling loops relative to one another.
13. A receiver system for wireless power, comprising:
a circuit configured to receive a signal at a first frequency and to produce an electrical output based on said first frequency;
an antenna resonant at said first frequency; and
a coupling loop assembly comprising:
a first coupling loop;
a first switch configured to activate said first coupling loop;
a second coupling loop; and
a second switch configured to activate said second coupling loop.
14. A system as in claim 13 , further comprising a controller configured to detect a coupling to the antenna, and to select either said first coupling loop or said second coupling loop based on said coupling.
15. A system as in claim 14 , wherein said controller is configured to detect proximity coupling and to select said first coupling loop upon detecting proximity coupling.
16. A system as in claim 14 , wherein said controller is configured to detect vicinity coupling and to select said second coupling loop upon detecting vicinity coupling.
17. A system as in claim 14 , wherein said antenna includes multiple loops.
18. A system as in claim 17 , further comprising a mechanism configured to adjust the position of said multiple loops relative to one another.
19. A system as in claim 14 , wherein said coupling loop assembly is unconnected to said antenna and coupling between said coupling loop assembly and said antenna is performed via magnetic induction.
20. A system as in claim 13 , wherein said coupling loops are formed on a printed circuit board.
21. A system as in claim 13 , wherein said antenna includes multiple loops.
22. A system as in claim 21 , further comprising a mechanism configured to adjust the position of said multiple loops relative to one another.
23. A system as in claim 13 , further comprising a mechanism configured to adjust the position of said coupling loops relative to one another.
24. An antenna, comprising:
multiple loops forming an inductive part;
a capacitor, in series with said multiple loops; and
a mover, configured to move said multiple loops relative to one another, changing a resonance frequency of said antenna.
25. A system as in claim 24 , wherein said mover comprises an electric motor.
26. A system as in claim 24 , wherein said mover comprises a pneumatic motor.
27. A system as in claim 24 , wherein said mover comprises a piezoelectric device.
28. A method of coupling electric power, comprising:
adjusting a coupling loop to transfer power via a first field upon detecting wireless power transfer via the first field between a pair of devices separated by less than a distance; and
adjusting the coupling loop to transfer power via a second field upon detecting wireless power transfer via the second field between the pair of devices separated by more than the distance.
29. A method as in claim 28 , wherein said adjusting comprises switching to use a second coupling loop rather than the coupling loop.
30. A method as in claim 28 , wherein adjusting comprises changing the size of the coupling loop.
31. A method as in claim 28 , wherein adjusting comprises adjusting the position of the coupling loop relative to a second coupling loop.
32. The method as in claim 28 , wherein the first field comprises a near-field.
33. The method as in claim 28 , wherein the second field comprises a far-field.
34. A system comprising:
means, resonant at a first frequency, for transmitting or receiving wireless power; and
means for coupling wireless power to and from said means for transmitting or receiving, said coupling means including:
means for a first coupling of wireless power to said means for transmitting or receiving;
means for activating said first coupling means;
means for a second coupling of wireless power to said means for transmitting or receiving wireless power; and
means for activating said second coupling means.
35. A system as in claim 34 , further comprising means for detecting a coupling to the means for transmitting or receiving wireless power, and selecting either said first coupling means or said second coupling means based on said detected coupling.
36. A system as in claim 35 , wherein said means for detecting a coupling detects proximity coupling and selects said first coupling means upon detecting said proximity coupling.
37. A system as in claim 35 , wherein said means for detecting a coupling detects vicinity coupling and selects said second coupling means upon detecting said vicinity coupling.
38. A system as in claim 34 , wherein said first and second coupling means are formed on a printed circuit board.
39. A system as in claim 34 , wherein said means for transmitting and receiving comprises multiple loops.
40. A system as in claim 39 , further comprising means for adjusting the position of said multiple loops relative to one another.
41. A system as in claim 34 , further comprising means for adjusting the position of said first and second coupling means relative to one another.
42. An antenna comprising:
means for producing inductive coupling;
means for adjusting a capacitance coupled in series with said means for producing inductive coupling; and
means for moving said means for inductive coupling, the means for moving configured to adjust a resonant frequency of the antenna based on a position of said means for producing inductive coupling.
43. A method of transmitting wireless power comprising:
detecting coupling to an antenna;
selecting a coupling loop based on said detected coupling; and
transferring wireless power from said coupling loop to said antenna via magnetic induction.
44. The method of claim 43 , wherein detecting coupling comprises detecting proximity coupling.
45. The method of claim 43 , wherein detecting coupling comprises detecting vicinity coupling.
46. The method of claim 43 , wherein selecting a coupling loop comprises switching from another coupling loop to the selected coupling loop.
47. The method of claim 43 , wherein selecting a coupling loop comprises adjusting a size of the selected coupling loop.
48. A method of receiving wireless power comprising:
detecting coupling to an antenna;
selecting a coupling loop based on the detected coupling;
receiving wireless power from the coupling loop at said antenna via magnetic induction; and
producing an electrical output based on said received wireless power.
49. The method of claim 48 , wherein detecting coupling comprises detecting proximity coupling.
50. The method of claim 48 , wherein detecting coupling comprises detecting vicinity coupling.
51. The method of claim 48 , wherein selecting a coupling loop comprises switching from another coupling loop to the selected coupling loop.
52. The method of claim 48 , wherein selecting a coupling loop comprises adjusting a size of the selected coupling loop.