METHODS AND SYSTEMS FOR WIRELESS POWER TRANSMISSION

• US 20110241618A1
• Filed: 06/17/2011
• Published: 10/06/2011
• Est. Priority Date: 07/12/2005
• Status: Abandoned Application

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Karalis, Aristeidis, Soljacic, Marin, Moffatt, Robert, Kurs, Andre B., Joannopoulos, John D., Fisher, Peter H.
• Application Number:
  US13/163,020
• Publication Number:
  US 20110241618A1
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: B60L 2210/20 AC to AC converters
• CPC Class Codes: B60L 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 9/04 Resonant antennas
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor

Abstract

In embodiments of the present invention improved capabilities are described for methods and systems for wireless power transmission utilizing high-Q resonators, where the resonators may resonate with an unmodulated carrier frequency, may be formed in a loop of conducting ribbon, may include an efficiency monitor, may provide for varying the amount of power transferred wirelessly, and applies a magnetic resonance phenomenon between a source and destination side resonator.

Claims

1. A high-Q wireless power transceiver, comprising:

a high-Q magnetic resonator configured to resonate at a substantially unmodulated carrier frequency;

wherein the resonator is configured to receive wireless power and to transmit wireless power.

2. The transceiver of claim 1, wherein power signals received by the high-Q magnetic resonator are converted from a substantially unmodulated carrier frequency to DC.

3. The transceiver of claim 1, wherein the high-Q magnetic resonator is tunable.

4. The transceiver of claim 3, wherein a resonant frequency of the resonator is determined at least in part by a tunable capacitance.

5. The transceiver of claim 1, wherein the magnetic resonator operates as a source of wireless power and as a receiver of wireless power.

6. A device, comprising:

a battery; and

a high-Q wireless power transceiver coupled to the battery.

7. The device of claim 6, further comprising drive and receive circuitry.

8. The device of claim 6, wherein the transceiver is a tunable resonator.

9. The device of claim 8, wherein a resonant frequency of the tunable resonator is determined at least in part by a tunable capacitance.

10. A method for transceiving wireless power, comprising:

receiving an induced current from a high-Q magnetic resonator resonating in response to a magnetic near-field and rectifying the induced current into DC power when the magnetic resonator is configured to receive wireless power; and

supplying a current at a resonant frequency to the high-Q magnetic resonator and generating a magnetic near-field from the high-Q magnetic resonator when the resonator is configured to transmit wireless power.

11. A wireless power transceiver, comprising:

means for receiving an induced current from a high-Q magnetic resonator resonating in response to a magnetic near-field and means for rectifying the induced current to DC when the resonator is configured to receive wireless power; and

means for supplying current at a resonant frequency into the high-Q resonator and means for generating a magnetic near-field from the high-Q resonator when the resonator is configured to transmit wireless power.

12. A high-Q resonator for wireless power transmission to a second high-Q resonator, the resonator comprising:

a capacitance and an inductance wherein the inductance comprises at least one loop formed of conducting ribbon;

and a magnetic material.

13. The resonator of claim 12, wherein the at least one loop includes a plurality of loops, with the plurality of loops being coaxially stacked.

14. The resonator of claim 13, wherein the plurality of loops are supported to maintain a predetermined gap between the plurality of loops.

15. The resonator of claim 13, wherein a size and a number of the plurality of loops are set to be suitable for resonance coupling through a desired frequency range.

16. The resonator of claim 13, wherein gaps between the plurality of loops are set to obtain a desired coupling strength.

17. The resonator of claim 12, wherein the at least one loop has a rectangular shape.

18. The resonator of claim 12, wherein the at least one loop has a circular shape.

19. A resonance type non-contact charging apparatus comprising:

a high frequency power source;

a source high-Q resonance coil that receives a high frequency power from the high frequency power source;

a device high-Q resonance coil arranged separated from and in a non-contact manner with respect to the source resonance coil, the device resonance coil receiving a power from the source resonance coil through magnetic field resonance between the source resonance coil and the device resonance coil;

a circuit that receives the high frequency power from the device resonance coil;

an efficiency monitor that detects an efficiency of transferred power; and

a control section that adjusts the high frequency power source based on the power transfer efficiency.

20. The apparatus according to claim 19, wherein the high frequency power source and the source resonance coil are installed on the ground, and the device resonance coil and the circuit are mounted in a vehicle.

21. The apparatus according to claim 20, wherein the vehicle is an electric vehicle.

22. The apparatus according to claim 19, wherein power received by a device resonance coil is used to charge a battery.

23. The apparatus according to claim 19, further comprising capacitors connected to the source resonance coil and the device resonance coil.

24. A wireless power transfer system, comprising:

a supply-side power supply coil;

a supply-side high-Q magnetic resonance coil;

a load-side power supply coil; and

a load-side high-Q magnetic resonance coil, wherein said supply-side magnetic resonance coil is excited, by supplying transmission electric powers of frequencies equal to magnetic resonance frequencies of said supply-side magnetic resonance coil and said load-side magnetic resonance coil to said supply-side power supply coil, thereby transferring an electric power, wirelessly, with applying a magnetic resonance phenomenon between said supply-side power supply coil and said load-side power supply coil, so as to take out the transmission electric power transferred to said supply-side magnetic resonance coil by said load-side power supply coil.

25. The wireless power transfer system, as described in the claim 24, further comprising power circuits coupled to said load-side power supply coil.

26. The wireless power transfer system, as described in the claim 24, further comprising at least one additional load-side power supply coil.

27. The wireless power transfer system, as described in the claim 26, further comprising power circuits coupled to said load-side power supply coil and said at least one additional load-side power supply coil.

28. The wireless power transfer system, as described in the claim 24, further comprising a rectifier circuit, which is configured to convert a transferring power having a frequency equal to a magnetic resonance frequency, which is outputted from said load-side power supply coil, into a DC power.

29. The wireless power transfer system, as described in the claim 24, wherein said supply-side power supply coil and said supply-side magnetic resonance coil are provided on a charger, and said load-side power supply coil and said load-side magnetic resonance coil are provided on an equipment mounting a rechargeable battery thereon.

30. A load apparatus in a wireless power transfer system, comprising:

a power supply apparatus having a supply-side power supply coil and a supply-side high-Q magnetic resonance coil; and

a load apparatus having a load-side power supply coil and a load-side high-Q magnetic resonance coil, wherein said supply-side magnetic resonance coil is excited, by supplying transmission electric powers of frequencies equal to magnetic resonance frequencies of said supply-side magnetic resonance coil and said load-side magnetic resonance coil to said supply-side power supply coil, thereby transferring an electric power, wirelessly, with applying a magnetic resonance phenomenon between said supply-side power supply coil and said load-side power supply coil, so as to take out the transmission electric power transferred to said supply-side magnetic resonance coil by said load-side power supply coil.

31. A method, comprising:

varying the amount of power transferred wirelessly from at least a first high-Q source magnetic resonator to at least a first high-Q device magnetic resonator.

32. The method of claim 31, wherein the amount of transferred power is varied based on information exchanged between the wireless power source resonator and the wireless power device resonator.

33. The method of claim 31, wherein the amount of transferred power is varied by de-tuning the at least first high-Q device magnetic resonator.

34. The method of claim 31, wherein the amount of transferred power is varied by adjusting the power in the source.

35. The method of claim 31, further comprising:

varying the amount of power transferred wirelessly from at least first high-Q source magnetic resonator to at least a second high-Q device magnetic resonator.

36. The method of claim 35, further comprising transferring different power levels to the different devices.

37. A wireless communication device, comprising:

a wireless power high-Q magnetic resonator configured to receive wireless power from a wireless power high-Q magnetic resonator source of wireless power;

an information channel configured to exchange information; and

an adjustment mechanism configured to adjust the amount of wireless power transferred to the wireless power receiver from the wireless power source based on said information exchange.

38. The wireless communication device of claim 37, wherein the amount of wireless power transferred is adjusted by de-tuning a resonator associated with the wireless power receiver.

39. The wireless communication device of claim 37, wherein the amount of wireless power transferred is adjusted by adjusting the power in the source based on the information exchange.

40. The wireless communication device of claim 39, wherein the source power is adjusted towards zero.

41. The wireless communication device of claim 37, wherein the device is configured to receive communication data from a communication link with an external device including at least one of a base station, satellite, server, personal computer, and a personal electronic device.

42. The wireless communication device of claim 41, wherein the device is configured according to at least one of CDMA, WCDMA, OFDM, 802.11, GPS, Bluetooth, LTE, LTE Advanced, and a near-field communication link.

43. A wireless power charger, comprising:

a wireless power high-Q magnetic resonator source configured for generating a magnetic field for transferring power to a wireless power high-Q magnetic resonator of a wireless power receiving device; and

an adjustment mechanism configured for adjusting a transferred power level based on information exchanged between the source and device resonators.

44. The wireless power charger of claim 43, wherein the adjustment mechanism reduces power generated by the wireless power source.

45. The wireless power charger of claim 43, further including a high-Q device magnetic resonator in communication with the adjustment mechanism, wherein the device resonator is configured for information exchange for controlling the amount of power transferred by the wireless power source.

46. The wireless power charger of claim 45, wherein the external device is the wireless power receiving device.

47. An apparatus, comprising:

means for varying the amount of wireless power transferred from a wireless power high-Q source magnetic resonator to a high-Q device magnetic resonator coupled to a first wireless communication device.