Electromagnetic device
The motors/generators of the preferred embodiments include a rotating part (rotor) and a stationary part (stator). In the devices disclosed, the primary function of the stator is to provide a high strength background magnetic field in which the rotor rotates. The rotor can be powered with a current that changes direction in concert with the relative change in magnetic field direction of the background field (that is, as the rotor moves from one magnetic pole to the next) in the case of a motor. In the case of a generator, the movement of the rotor generally results in the generation of an alternating voltage and current.
1. An electromagnetic device, comprising:
a stator;
a rotor; and
a gap comprising one or more gap regions;
wherein:
one of the rotor and the stator includes a conductor array accommodated in the gap, the conductor array having one or more conductors each configured to carry current in a respective current-flow direction and configured to move relative to the other of the rotor and stator;
the other of the rotor and stator includes electromagnetic coils wound in the form of one or more toroidal sectors, each toroidal sector comprising end portions and an intermediate portion between the end portions;
the end portions of each of the one or more toroidal sectors are configured to direct magnetic flux through a respective gap region in a substantially perpendicular direction to the respective current-flow direction of the one or more conductors moving through the respective gap region; and
the intermediate portion of each of the one or more toroidal sectors is configured to redirect magnetic flux exiting from a respective gap region to the same or different gap region to facilitate at least one circulating magnetic flux path through the one or more gap regions.
2. The electromagnetic device of claim 1 wherein the at least one circulating magnetic flux path forms a single closed loop.
3. The electromagnetic device of claim 1 wherein the at least one circulating magnetic flux path forms multiple closed loops.
4. The electromagnetic device of claim 1 wherein the electromagnetic coils include superconducting coils.
5. The electromagnetic device of claim 4 , wherein the at least one superconducting coils are at least partially enclosed within a cryogenic envelope.
6. The electromagnetic device of claim 1 wherein the electromagnetic coils are in the form of one or more racetrack coils.
7. The electromagnetic device of claim 6 , wherein the one or more racetrack coils consist of first and second concentric racetrack coils both configured to carry current in the same direction.
8. The electromagnetic device of claim 1 , wherein the other of the rotor or stator includes one or more permanent magnets.
9. The electromagnetic device of claim 1 , wherein the other of the rotor or stator includes one or more ferromagnetic flux guides.
10. The electromagnetic device of claim 1 wherein the magnetic flux through the respective gap region is in a radial direction of the rotor and the current-flow direction is in an axial direction of the rotor.
11. The electromagnetic device of claim 10 , wherein the one or more toroidal sectors comprises one or more inner toroidal sectors and one or more outer toroidal sectors and wherein the gap is formed between the inner and outer toroidal sectors.
12. The electromagnetic device of claim 10 , wherein the conductor array is cylindrical in shape.
13. The electromagnetic device of claim 12 , wherein the conductor array is arranged in a zig-zag winding along the length of the cylindrical shape.
14. The electromagnetic device of claim 10 , wherein the conductor array includes one or more racetrack coils.
15. The electromagnetic device of claim 10 , wherein the conductor array is formed from one or more bedstead-style windings.
16. The electromagnetic device of claim 1 wherein the magnetic flux through the respective gap region is in an axial direction of the rotor and the current-flow direction is in a radial direction of the rotor.
17. The electromagnetic device of claim 16 wherein the conductor array is in the form of a disc.
18. The electromagnetic device of claim 17 wherein the conductor array is arranged in a zig-zag winding along the radial direction of the disc.
19. The electromagnetic device of claim 16 , wherein the conductor array includes one or more racetrack coils.
20. The electromagnetic device of claim 16 , wherein the conductor array is formed from one or more bedstead-style windings.