METHOD AND SYSTEM FOR LONG RANGE WIRELESS POWER TRANSFER

• US 20120010079A1
• Filed: 06/01/2011
• Published: 01/12/2012
• Est. Priority Date: 06/01/2010
• Status: Active Grant

• Current Assignee: University of Maryland
• Original Assignee: University of Maryland
• Inventors: SEDWICK, RAYMOND J.
• Granted Patent: US 8,994,221 B2
• Time in Patent Office: Days
• US Class Current: 505/163
• 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
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H03B 15/003 using superconductivity effects devices using superconductivity H10N60/00

Abstract

A wireless energy transfer system includes a primary and one (or more) secondary oscillators for transferring energy therebetween when resonating at the same frequency. The long range (up to and beyond 100 m) efficient (as high as and above 50%) energy transfer is achieved due to minimizing (or eliminating) losses in the system. Superconducting materials are used for all current carrying elements, dielectrics are either avoided altogether, or those are used with a low dissipation factor, and the system is operated at reduced frequencies (below 1 MHz). The oscillators are contoured as a compact flat coil formed from a superconducting wire material. The energy wavelengths exceed the coils diameter by several orders of magnitude. The reduction in radiative losses is enhanced by adding external dielectric-less electrical capacitance to each oscillator coil to reduce the operating frequency. The dielectric strength of the capacitor is increased by applying a magnetic cross-field to the capacitor to impede the electrons motion across an air gap defined between coaxial cylindrical electrodes.

Claims

1. A system for long range wireless energy transfer, comprising:

a first oscillator structure coupled to a power source and at least one second oscillator structure displaced from said first oscillator structure a distance D to receive energy therefrom,

wherein said first and at least one second oscillator structures are configured into compact coils, said first and said at least one second oscillator structures being formed from a superconducting material composition and resonating substantially at the same frequency maintained below a predetermined frequency level sufficient for providing energy coupling between said first and said at least one second oscillator structures.

2. The system of claim 1, wherein each of said compact coils of said first and at least one second oscillator structure is a flat coil having a plurality of windings positioned in the same plane.

3. The system of claim 1, wherein said predetermined frequency level is below approximately 1 MHz.

4. The system of claim 1, wherein said predetermined distance D falls in the range covering approximately 10'"'"'s m and exceeding 100 m.

5. The system of claim 1, wherein said power source is coupled up-stream of said first oscillating structure, said system further including at least one power consuming unit coupled down-stream of said at least one second oscillating unit, a drive coil coupled between said power source and said first oscillator structure, and a drain coil coupled between said at least one second oscillator structure and said at least one power consuming unit.

6. The system of claim 1, wherein diameters of said compact coils of said first and said at least one second oscillator structures fall in the range between 10 cm and several meters.

7. The system of claim 1, further comprising a plurality of capacitor elements, each coupled to a respective one of said first and said at least one second oscillator structures, said each capacitor element including an inner cylindrical electrode and at least one outer cylindrical electrode disposed in a co-axial surrounding relationship with said inner cylindrical electrode, wherein at least one air gap is defined between cylindrical walls of said inner and at least one outer cylindrical electrodes.

8. The system of claim 7, wherein said each capacitor element is formed from a superconducting material.

9. The system of claim 8, wherein the superconducting material for said first and at least one oscillator structures and said each capacitor element is selected from the group consisting of Type I superconductors, High Temperature Superconductors, including BSCCO, and YBCO, and room temperature superconductors.

10. The system of claim 8, further comprising a thermo-control system including a plurality of cryogenical units, each operatively engaged with a respective one of said first and at least one second oscillator structures, and said each capacitor element, to maintain said superconducting material thereof at a predetermined temperature level.

11. The system of claim 7, wherein each of said first and at least one second oscillator elements, and said each capacitor element is a dielectric-less component.

12. The system of claim 7, wherein said at least one air gap is filled with a dielectric material having a low dissipation factor.

13. The system of claim 11, further comprising a magnetic field applied axially to said each capacitor element to increase a breakdown voltage threshold in said at least one air gap, thereby increasing the dielectric strength of air in said at least one air gap of said each dielectric-less capacitor element.

14. The system of claim 2, further comprising a dielectric material with a negligible dissipation factor disposed between said windings in said flat coils of said first and said at least one second oscillator structures.

15. The system of claim 1, further comprising at least one booster resonator coil positioned between said first and said at least one second oscillator structures, said at least one booster resonator coil resonating in phase with said first oscillator structure to receive energy therefrom, and in phase with said at least one second oscillator structure to transfer energy thereto.

16. The system of claim 7, wherein the length of said each capacitor element l cm≈

2 bcm, wherein lcm is the length of said capacitor element, and bcm is the radius of said at least one outer cylindrical electrode in cm.

17. The system of claim 16, wherein the volume of said each capacitor element is

18. A method for long range wireless energy transfer, comprising the steps of:

fabricating first and at least one second oscillator structures as compact flat coils formed from a superconducting material,

displacing said at least one second oscillator structure a distance D from said first oscillator structure,

coupling said first oscillator structure to a power source, and

generating an oscillating current of a resonant frequency in said first oscillator structure, wherein said oscillating current creates an oscillating field, and

sensing said oscillating current by said at least one second oscillator structure, thereby causing oscillation of said at least one second oscillator structure at said resonant frequency, and thereby transferring energy from said first oscillator structure to said at least one second oscillator structure,

wherein said resonant frequency is maintained below a predetermined frequency level providing a strong energy coupling between said first and said at least one second oscillator structures.

19. The method of claim 18, further comprising the steps of:

coupling a capacitor element to at least one of said first and at least one second oscillator structures,

said capacitor element including an inner cylindrical electrode and at least one outer cylindrical electrode co-axially disposed around said inner cylindrical electrode, wherein at least one air gap is defined between cylindrical walls of said inner and at least one outer cylindrical electrodes, and

applying a magnetic field axially to said capacitor element to increase dielectric strength of air in said at least one air gap.

20. The method of claim 18, wherein said capacitor element is formed from a superconducting material,

wherein said predetermined frequency level is 200 KHz,

wherein said distance D exceeds 100 m, and

wherein said first and at least one second oscillator structures and said capacitor element are dielectric-less components.