Direct-drive generator/motor for a windmill/hydropower Plant/Vessel where the generator/morot is configured as a hollow profile and a method to assemble such a windmill/hydropower plant

• US 8,222,762 B2
• Filed: 10/13/2006
• Issued: 07/17/2012
• Est. Priority Date: 10/13/2005
• Status: Expired due to Fees

• Current Assignee: Sway Turbine AS
• Original Assignee: Sway AS
• Inventors: Borgen, Eystein
• Primary Examiner(s): Cuevas, Pedro J
• Application Number:
  US12/089,536
• Publication Number:
  US 20080292467A1
• Time in Patent Office: 2,104 Days
• Field of Search: 290/44, 290/55
• US Class Current: 290/55
• CPC Class Codes: B63H 13/00 Marine propulsion by wind motors driving water-engaging propulsive elements
• CPC Class Codes: F03B 13/10 Submerged units incorporating electric generators or motors
• CPC Class Codes: F03D 13/10 Assembly of wind motors; Arrangements for erecting wind motors
• CPC Class Codes: F03D 13/20 Arrangements for mounting or supporting wind motors; Masts or towers for wind motors
• CPC Class Codes: F03D 15/20 Gearless transmission, i.e. direct-drive
• CPC Class Codes: F03D 80/70 Bearing or lubricating arrangements
• CPC Class Codes: F03D 9/25 the apparatus being an electrical generator F03D9/22 takes precedence
• CPC Class Codes: F05B 2220/7068 equipped with permanent magnets
• CPC Class Codes: F05B 2240/51 magnetic
• CPC Class Codes: F05B 2240/515 electromagnetic
• CPC Class Codes: F16C 2326/30 Ships, e.g. propelling shafts and bearings therefor
• CPC Class Codes: F16C 2360/31 Wind motors
• CPC Class Codes: F16C 32/0436 with a conductor on one part movable with respect to a magnetic field, e.g. a body of copper on one part and a permanent magnet on the other part
• CPC Class Codes: H02K 1/2795 the rotor consisting of two or more circumferentially positioned magnets
• CPC Class Codes: H02K 7/09 with magnetic bearings
• CPC Class Codes: H02K 7/14 Structural association with mechanical loads, e.g. with hand-held machine tools or fans with fan or impeller for cooling the machine H02K9/06
• CPC Class Codes: H02K 7/1838 Generators mounted in a nacelle or similar structure of a horizontal axis wind turbine
• CPC Class Codes: Y02E 10/20 Hydro energy
• CPC Class Codes: Y02E 10/30 Energy from the sea, e.g. using wave energy or salinity gradient
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/728 : Onshore wind turbines
• CPC Class Codes: Y02T 70/5236 : Renewable or hybrid-electric solutions

Abstract

A turbine rotor for a wind power plant or a hydropower plant with a direct-drive generator for converting the energy in flowing wind or water into electrical energy wherein the wind or hydropower plant comprises a turbine rotor and a stator and wherein the turbine rotor further comprises a ring-shaped hub (6) having an axis of rotation that coincides with the center axis of the stator and wherein the turbine rotor comprises at least one rotor blade, which rotor blade is arranged on the ring-shaped hub. The turbine rotor is also intended to be used as a propeller for a craft.

Claims

1. A turbine rotor for a wind power plant or hydro power plant or for propulsive means for a vessel, the turbine rotor comprising a rigid ring-shaped hub with an axis of rotation, the rigid ring-shaped hub, in a side view cross-section, being configured as a closed, hollow profile, the ring-shaped hub further being configured as a torus with a circular cross section or a torus with a polygonal cross section, wherein a section through the ring-shaped hub perpendicular to said axis of rotation is ring-shaped, the outer and the inner circumferences of the ring being circular or polygonal, and wherein the turbine rotor further comprises at least one elongated, rigid rotor blade which is arranged on the ring-shaped hub on the opposite side of the ring-shaped hub relative to said axis of rotation.

2. A turbine rotor according to claim 1, wherein the side view cross sectional diameter of the ring-shaped hub is of substantially the same size as the diameter of the at least one blade at the point of attachment of the blade.

3. A turbine rotor according to claim 1, wherein the generator rotor is mounted to the ring-shaped hub.

4. A turbine rotor according to claim 1, wherein the distance from the axis of rotation of the turbine rotor to the outer circumference of the ring-shaped hub around the axis of rotation of the turbine rotor is at least 1/12 of the radius of the turbine rotor from the axis of rotation to a blade tip.

5. A turbine rotor according to one of the claims 1-4, wherein the wind turbine rotor comprises at least two tension rods which at their first ends are attached to a bearing that is coaxial with the centre axis of the stator and at their second ends are fastened to the ring-shaped hub.

6. A turbine rotor according to claim 5, wherein that the tension rods lie in one and the same plane.

7. A turbine rotor according to one of the claims 1-4, wherein the wind turbine rotor comprises at least two pressure rods which at their first ends are fastened to a bearing that is coaxial with the centre axis of the stator and at their second ends are fastened to the ring-shaped hub.

8. A turbine rotor according to claim 7, wherein the pressure rods lie in one and the same plane.

9. Wind power plant or hydro power plant, or a vessel,

wherein the wind or hydro power plant or the vessel comprises a turbine rotor according to claim 1.

10. A power plant comprising a direct-drive generator for converting the energy in wind or flowing water into electrical energy, the power plant comprising a tower structure and a turbine rotor, the direct-drive generator comprising a generator rotor, a stator which is mounted on the tower structure and a bearing supporting the turbine rotor on the stator, wherein the turbine rotor is formed according to claim 1 and wherein said bearing and said generator rotor are mounted on the rigid ring-shaped hub of the turbine rotor, the turbine rotor having an axis of rotation that coincides with the centre axis of the stator of the direct-drive generator.

11. A power plant according to claim 10, wherein the turbine rotor is supported on the stator by a magnetic bearing consisting of either permanent magnets, electromagnets or a combination of both.

12. A power plant according to claim 11, wherein the magnetic bearing is a passive magnetic bearing.

13. A power plant according to claim 11, wherein the magnetic bearing is a passive magnetic bearing with the magnets arranged in a Halbach array.

14. A power plant according to one of the claim 11, wherein the magnets in the stator are replaced by short-circuited electrical conductors.

15. A power plant according to one of the claim 13, wherein the magnets in the stator are replaced by short-circuited electrical conductors.

16. A power plant according to claim 11, wherein the magnetic bearing is an electromagnetic bearing.

17. A power plant according to claim 11, wherein current-producing windings are installed without magnetically conducting iron cores.

18. A power plant according to claim 17, wherein the generator magnets consist of permanent magnets arranged in a Halbach array.

19. A power plant according to claim 10, wherein the turbine rotor is supported on the stator by a conventional bearing.

20. A power plant according to claim 10, wherein the turbine rotor is supported by a magnetic bearing axially against the stator and that the turbine rotor is supported radially by a conventional bearing.

21. A power plant according to one of the claims 11-18, wherein the shortest distance from the axis of rotation of the ring-shaped hub to the area centre of the force transferring face of the magnetic bearing is smaller than the distance from the axis of rotation of the ring-shaped hub to the neutral axis of the side view cross-section of the ring-shaped hub.

22. A power plant according to one of the claims 11-20, wherein the bending stiffness of the ring-shaped hub for bending out of a plane that passes through the ring-shaped hub and is perpendicular to the axis of rotation of the ring-shaped hub is greater than the bending stiffness of the stator for bending out of the same plane.

23. A power plant according to one of the claims 11-20, wherein the bending stiffness of the ring-shaped hub for bending out of a plane that runs through the ring-shaped hub and is perpendicular to the axis or rotation of the ring-shaped hub is at least twice as great as the bending stiffness of the stator for bending out of the same plane.

24. A wind power plant comprising a

turbine rotor comprising a ring-shaped hub with an axis of rotation,

at least one rotor blade which is arranged on the ring-shaped hub on the opposite side of the ring-shaped hub relative to said axis of rotation

a tower structure,

a direct drive generator comprising a generator rotor and a stator, the stator being mounted on the tower structure,

wherein the ring-shaped hub is configured as a torus with a closed hollow profile, the generator rotor is mounted on the ring-shaped hub and wherein the turbine rotor and the generator rotor are supported on the stator such that axial forces caused by wind pressure are transferred to the stator.

25. A wind power plant according to claim 24, wherein the stator is supported by bending stiff beams which conduct said forces into the rest of the supporting tower structure.

26. A wind power plant according to claim 24, wherein the stator comprises a short annular ring with a peripheral diameter which is adapted to a peripheral diameter of the ring-shaped hub.

27. A wind power plant according to claim 24, wherein there is arranged a spoke system between the ring-shaped hub and a mechanical bearing arranged against the tower structure.

28. A wind power plant according to claim 24, wherein the wind power plant further comprises a magnetic bearing between the ring-shaped hub and the stator.