HIGH EFFICIENCY AND POWER TRANSFER IN WIRELESS POWER MAGNETIC RESONATORS

• US 20100181844A1
• Filed: 03/18/2010
• Published: 07/22/2010
• 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:
  US12/726,953
• Publication Number:
  US 20100181844A1
• Time in Patent Office: Days
• US Class Current: 307/104
• 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

Described herein are embodiments of a wireless power system that include a signal generator, having a connection to a source of power, and which creates a substantially unmodulated signal at a first frequency, a transmitting high-Q resonator, generating a magnetic field having said first frequency and based on power created by said signal generator, a receiving high-Q resonator, receiving a magnetic power signal created by said transmitting resonator, said receiving resonator being a distance greater than 1 m spaced from said transmitting resonator, and a load receiving part, receiving power from said receiving resonator, wherein a transfer efficiency between said transmitting resonator and said receiving resonator is greater than 25% at 1 m of distance between said transmitting resonator and said receiving resonator.

Claims

1. A wireless power system, comprising:

a signal generator, having a connection to a source of power, and which creates a substantially unmodulated signal at a first frequency; and

a transmitting high-Q resonator, generating a magnetic field having said first frequency and based on power created by said signal generator;

a receiving high-Q resonator, receiving a magnetic power signal created by said transmitting resonator, said receiving resonator being a distance greater than 1 m spaced from said transmitting resonator, and

a load receiving part, receiving power from said receiving resonator;

wherein a transfer efficiency between said transmitting resonator and said receiving resonator is greater than 25% at 1 m of distance between said transmitting resonator and said receiving resonator.

2. A system as in claim 1, wherein said transmitting resonator transmits a power of 25 W.

3. A system as in claim 1, wherein said transfer efficiency is greater than 25% at 1.5 m distance between said transmitting resonator and said receive resonator.

4. A system as in claim 1, wherein said transmitter resonator is a capacitively loaded dipole, and said receive resonator is a capacitively loaded dipole.

5. The system as in claim 1, further comprising a coupling loop, on the transmitting resonator, coupled directly to said signal generator, and unconnected by any wire connection to said transmitting resonator.

6. The system as in claim 5, further comprising a coupling loop, coupled between said receiving electronics and said receiving resonator, such that said receiving electronics are not directly connected by any wire to said receiving resonator.

7. The system of claim 1, further comprising a tuning loop, movable relative to said receiver, and said movement effecting a resonant frequency of said receiver.

22. A system as in claim 1, wherein said transmitting and said receive high-Q resonators are both capacitively loaded.

8. A method of transmitting power wirelessly, comprising:

creating a substantially unmodulated signal at a first frequency based on power from a power source; and

using a transmitting high-Q resonator to generate a magnetic field having said first frequency and based on said power from said power source;

wirelessly receiving the magnetic field created by said transmitting resonator at a distance greater than 1 m spaced from said transmitting resonator, and

coupling power from said receiving, to a load, with a transfer efficiency between said transmitting resonator and said receiving high-Q resonator greater than 25%.

9. A method as in claim 8, wherein said transmitting resonator transmits a power of 25 W.

10. A method as in claim 8, wherein said transfer efficiency is greater than 25% at 1.5 m distance between said transmitting resonator and said receiving resonator.

11. A method as in claim 8, wherein said transmitter resonator is a capacitively loaded dipole, and said receive resonator is a capacitively loaded dipole.

12. The method as in claim 8, further comprising using a coupling loop, on the transmitting resonator, between said signal generator and said transmitting resonator, such that said signal generator is not directly connected by a wire to said transmitting resonator.

13. The method as in claim 8, wherein the signal generator is an RF generator.

14. The method as in claim 12, further comprising using a coupling loop, coupled between said receiving electronics and said receiving resonator, such that said receiving electronics are not directly coupled to said receiving resonator.

15. The method as in claim 8, further comprising moving a tuning loop, movable relative to said receiver, wherein a resonant frequency of said receiver is changed by said moving.

23. A method as in claim 8, wherein said transmitting and said receive high-Q resonators are both capacitively loaded.

16. A wireless power system, comprising:

a signal generator, having a connection to a source of power, which creates a substantially unmodulated signal at a first frequency;

a transmitting high-Q resonator, generating a magnetic field having said first frequency and based on power created by said signal generator;

a receiving high-Q resonator, receiving a magnetic power signal created by said transmitting resonator, and said receiving resonator being a distance greater than 1 m spaced from said transmitting resonator; and

a load receiving part, receiving power from said receiving resonator;

wherein said load receives a power of at least 2½

Watts at a distance of 1½

meters from said transmitting resonator.

17. A system as in claim 16, wherein said transmitting resonator transmits a power of 25 W.

18. A system as in claim 16, wherein said transmitter resonator is a capacitively loaded dipole, and said receive resonator is a capacitively loaded dipole.

19. The system as in claim 16, further comprising a coupling loop, on the transmitting resonator, coupling directly to said signal generator, and unconnected by any wire connection to said transmitting resonator.

20. The system as in claim 16, further comprising a coupling loop, coupled between said receiving electronics and said receiving resonator, such that said receiving electronics are not directly connected by any wire to said receiving resonator.

21. The system as in claim 16, further comprising a tuning loop, movable relative to said receiver, and said movement affecting a resonant frequency of said receiver.

24. A system as in claim 16, wherein said transmitting and said receive high-Q resonators are both capacitively loaded.