APPARATUS AND METHOD FOR WIRELESS POWER TRANSFER

• US 20140028112A1
• Filed: 01/14/2011
• Published: 01/30/2014
• Est. Priority Date: 01/14/2011
• Status: Active Grant

• Current Assignee: City University of Hong Kong
• Original Assignee: City University of Hong Kong
• Inventors: Hui, Ron Shu Yuen, Zhong, Wenxing
• Granted Patent: US 10,566,133 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• 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 50/005 Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/50 using additional energy repeaters between transmitting devices and receiving devices

Abstract

The present invention provides an apparatus for wireless power transfer including three or more coils, each coil defining a respective coil plane, and the coils being arranged in one or more power flow paths whereby each coil can be magnetically coupled to one or more of the other coils thereby to wirelessly transfer power along the one or more power flow paths. The present invention also provides a method for wirelessly transferring power, the method including: providing three or more coils, each coil defining a respective coil plane; and arranging the coils in one or more power flow paths whereby each coil can be magnetically coupled to one or more of the other coils thereby to wirelessly transfer power along the one or more power flow paths.

Claims

1. An apparatus for wireless power transfer including three or more coils, each coil defining a respective coil plane, and the coils being arranged in one or more power flow paths whereby each coil can be magnetically coupled to one or more of the other coils thereby to wirelessly transfer power along the one or more power flow paths.

2. An apparatus according to claim 1 wherein one or more of the coils can be configured such that the respective coil plane deviates from being perpendicular to the power flow path in which it is arranged, thereby varying the mutual inductance between the one or more coil and an adjacent coil.

3. An apparatus according to claim 1 wherein one or both of a resonant frequency and an impedance of one or more of the coils can be varied.

4. An apparatus according to claim 3 wherein one or more of the coils has a capacitance or an inductance or both thereof, and the resonant frequency of the one or more coils can be varied by varying the capacitance or the inductance or both thereof.

5. An apparatus according to claim 1 wherein one or more of the power flow paths split into further power flow paths.

6. An apparatus according to claim 1 wherein two or more of the power flow paths merge into fewer power flow paths.

7. An apparatus according to claim 1 wherein one or more of the power flow paths are straight, curved, circular, irregular-shaped, or any combination thereof.

8. An apparatus according to claim 1 wherein the coils form part of a tubular structure.

9. An apparatus according to claim 8 wherein the tubular structure is flexible.

10. An apparatus according to claim 1 wherein one or more of the coils are adapted to receive power from a power supply, the power being wirelessly transferable along one or more of the power flow paths via mutual induction between the coils.

11. An apparatus according to claim 1 wherein one or more of the coils are adapted to provide power to a power consuming device.

12. An apparatus according to claim 1 wherein the magnetic coupling between two or more of the coils is resonant.

13. An apparatus according to claim 1 wherein the magnetic coupling between the coils is non-radiative.

14. An apparatus according to claim 1 wherein the ratio of the distance between any two of the coil planes and half the maximum dimension of any of said two coil planes is less than 3.

15. An apparatus according to claim 1 wherein the distance between a pair of the coil planes is unequal with the distance between another pair of the coil planes.

16. An apparatus according to claim 1 wherein the respective distances between different pairs of the coil planes are selected to maximize the efficiency of the wireless power transfer.

17. An apparatus according to claim 1 wherein the coils have an operating frequency of less than 100 MHz.

18. An apparatus according to claim 1 wherein the coils have an operating frequency of less than 10 MHz.

19. An apparatus according to claim 1 wherein the coils have an operating frequency of less than 5 MHz.

20. An apparatus according to claim 1 wherein the coils have an operating frequency of less than 1 MHz.

21. An apparatus according to claim 1 wherein the coils have an operating frequency of greater than 10 kHz.

22. A method for wirelessly transferring power, the method including:

providing three or more coils, each coil defining a respective coil plane; and

arranging the coils in one or more power flow paths whereby each coil can be magnetically coupled to one or more of the other coils thereby to wirelessly transfer power along the one or more power flow paths.

23. A method according to claim 22 including configuring one or more of the coils such that the respective coil plane deviates from being perpendicular to the power flow path in which it is arranged, thereby varying the mutual inductance between the one or more coil and an adjacent coil.

24. A method according to claim 22 including varying one or both of a resonant frequency and an impedance of one or more of the coils.

25. A method according to claim 22 wherein one or more of the coils has a capacitance or an inductance or both thereof, and the method includes varying the capacitance or the inductance or both thereof, thereby to vary the resonant frequency of the one or more coils.

26. A method according to claim 22 wherein the coils are arranged such that one or more of the power flow paths split into further power flow paths.

27. A method according to claim 22 wherein the coils are arranged such that two or more of the power flow paths merge into fewer power flow paths.

28. A method according to claim 22 wherein the coils are arranged such that one or more of the power flow paths are straight, curved, circular, irregular-shaped, or any combination thereof.

29. A method according to claim 22 wherein the coils are provided as part of a tubular structure.

30. A method according to claim 29 wherein the tubular structure is flexible.

31. A method according to claim 22 wherein one or more of the coils are adapted to receive power from a power supply, the power being wirelessly transferable along one or more of the power flow paths via mutual induction between the coils.

32. A method according to claim 22 wherein one or more of the coils are adapted to provide power to a power consuming device.

33. A method according to claim 22 wherein two or more of the coils are configured such that the magnetic coupling between said coils is resonant.

34. A method according to claim 22 wherein the coils are configured such that the magnetic coupling between the coils is non-radiative.

35. A method according to claim 22 wherein the coils are arranged such that the ratio of the distance between any two of the coil planes and half the maximum dimension of any of said two coil planes is less than 3.

36. A method according to claim 22 wherein the coils are arranged such that the distance between a pair of the coil planes is unequal with the distance between another pair of the coil planes.

37. A method according to claim 22 wherein the coils are arranged such that the respective distances between different pairs of the coil planes are selected to maximize the efficiency of the wireless power transfer.

38. A method according to claim 22 wherein the coils are provided with an operating frequency of less than 100 MHz.

39. A method according to claim 22 wherein the coils are provided with an operating frequency of less than 10 MHz.

40. A method according to claim 22 wherein the coils are provided with an operating frequency of less than 5 MHz.

41. A method according to claim 22 wherein the coils are provided with an operating frequency of less than 1 MHz.

42. A method according to claim 22 wherein the coils are provided with an operating frequency of greater than 10 kHz.