Device for producing eletric current from wind energy

• US 20030194310A1
• Filed: 12/19/2002
• Published: 10/16/2003
• Est. Priority Date: 06/19/2000
• Status: Active Grant

• Current Assignee: Areva Np (AES Corporation)
• Original Assignee: Jeumont S.A.
• Inventors: Milet, Yves, Brutsaert, Patrick, Canini, Jean-Marc
• Granted Patent: US 6,921,243 B2
• Time in Patent Office: Days
• US Class Current: 415/4.2
• CPC Class Codes: F03D 80/00 Details, components or accessories not provided for in groups F03D1/00 - F03D17/00
• 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 2220/7066 via a direct connection, i.e. a gearless transmission
• CPC Class Codes: F05B 2240/14 Casings, housings, nacelles, gondels or the like, protecting or supporting assemblies there within
• CPC Class Codes: H02K 7/102 with friction brakes
• CPC Class Codes: H02K 7/1838 Generators mounted in a nacelle or similar structure of a horizontal axis wind turbine
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y10S 415/908 Axial flow runner

Abstract

The system comprises a nacelle (3) mounted to turn about a vertical axis on the top of a mast (2) and carrying a rotary portion (10) which rotates about a substantially horizontal axis in a large diameter bearing (15). The rotary portion (10) comprises a hub (13) to which blades (14) are fixed. The system has an electric generator (12) comprising a stator (17) and a rotor (16) in the shape of a disk. The rotor (16) is fixed by a connecting member (20) to the hub (13) adjacent the bearing (15) so that the forces exerted by the wind on the rotary portion (10) are transmitted directly to the bearing (15) without passing through the electric generator (12).

Claims

1. A system for producing electricity from wind energy, the system comprising a vertical mast (2) having a bottom end portion fixed to a support surface, a nacelle (3) mounted to turn about a vertical axis on a top end portion of the mast (2), a rotary portion (10) comprising a hub (13) and two or more substantially radial blades (14) fixed to the hub (13), a bearing (15) in which the rotary portion (10) of the nacelle (3) rotates and which has a substantially horizontal axis, and an electricity generator (12) comprising a stator (17) secured to the nacelle (3) and a rotor (16) secured to the hub (13) of the rotary portion (10) by a fixing member (20) substantially perpendicular to the rotation axis of the rotary portion (10), which system is characterized in that:

both the rotor (16) and the stator (17) have respective active portions each in the form of a disk carrying facing electromagnetic members (19, 19′

),

the rotary portion (10) rotates on the nacelle (3) in a single bearing (15) whose diameter is less than 20% less than the diameter of a circle inscribed in the cross section perpendicular to the axis of the rotary portion (10) of a surface formed by areas in which the blades (14) are connected to the hub (10), and

the fixing member (20) fixing the rotor (16) to the hub (13) is adjacent the bearing (15) in the axial direction of the bearing (15).

2. A system according to claim 1, characterized in that the fixing member (20) connecting the rotor (16) to the hub (13) is annular and has an inner portion connecting it to the hub (13) and to a rotary inner race of the rolling bearing (15) between the hub (13) and the bearing (15) in the axial direction of the hub (13) and the bearing (15), to both of which the fixing member (20) is rigidly fixed, for example by tie-rods.

3. A system according to claim 1 or claim 2, characterized in that it comprises a first subassembly comprising a main frame (8) rotatably mounted on the top portion of the mast (2), a second subassembly fixed to the first subassembly at a junction plane (11) and comprising, on a support frame (9), the electricity generator (12) consisting of the stator (17), the rotor (16), and the bearing (15), and a third subassembly connected to the second subassembly at the location of the bearing (15) and comprising the hub (13) and the blades (14) of the rotary portion (10), the three subassemblies being interconnected by flanges to absorb forces exerted by the wind on the rotary portion (10) on the first subassembly via the second subassembly, the first subassembly enclosing various system components.

4. A system according to any one of claims 1 to 3, characterized in that the active portions in the form of disks of the rotor and the stator are separated by an airgap whose width is adjusted so that the stator (17) exerts on the rotor (16) and on the rotary portion (10) an axial force in the opposite direction to the axial force exerted by the wind on the rotary portion (10).

5. A system according to any one of claims 1 to 4, characterized in that it further comprises a mechanical brake (22) for the rotary portion (10) consisting of a disk brake whose disk is secured to the rotor (16) of the electricity generator (12) and which includes a plurality of calipers for braking the disk distributed around the outside periphery of a portion of a frame (8) of the nacelle (3).

6. A system according to claim 5, characterized in that it further comprises an aerodynamic braking system consisting of radial end portions (14a) of the blades (14) opposite the ends of the blades (14) connected to the hub (13), adapted to rotate about a longitudinal axis of the corresponding radial blade and connected to a system for pivoting the end portion (14a) of the blade as a function of the wind speed or the speed of rotation of the rotary portion (10).

7. A system according to any one of claims 1 to 6, characterized in that the bearing (15) is a rolling bearing and the nacelle (3) includes a system for lubricating the rolling bearing (15).

8. A system according to any one of claims 1 to 7, characterized in that the bearing (15) is practically adjacent the hub (13) in the axial direction so that the rotary portion (10) of the system is fixed to the frame (8) of the nacelle (3) with a cantilever that is small.

9. A system according to any one of claims 1 to 8, characterized in that an active portion of the rotor (16) in the form of a disk carries permanent magnets distributed in the circumferential direction of the active portion of the rotor (16).