WIND-TURBINE ROTOR BLADE, AND WIND TURBINE HAVING SAME

Abstract

A wind-turbine rotor blade, comprising a blade root and a blade tip, a flange arranged on the blade root side for fastening the rotor blade to a rotor hub of a wind turbine, and a pitch bearing for adjusting the angle of attack of the rotor blade. The rotor blade has a non-pitched carrier, on which the flange is embodied, wherein the pitch bearing is fastened to the carrier and is spaced apart from the flange toward the blade tip.

Claims

1. A wind-turbine rotor blade, comprising: a blade root and a blade tip; a flange arranged on the blade root side for fastening the rotor blade to a rotor hub of a wind turbine; a pitch bearing for adjusting an angle of attack of the rotor blade; and a non-pitched carrier, wherein the flange is embodied on the non-pitched carrier, wherein the pitch bearing is fastened to the non-pitched carrier and is spaced apart from the flange toward the blade tip, wherein the non-pitched carrier, between the pitch bearing and the flange, has a section, which is angled in such a way with respect to a pitch axis that, in wind turbine-mounted state of the rotor blade, the pitch axis is spaced apart farther from a tower axis of the wind turbine than the flange.

2. The rotor blade according to claim 1, further comprising has an outer structure and an aerodynamic blade surface being formed on the outer structure, wherein the outer structure is supported on the non-pitched carrier so as to be capable of being rotated about a pitch axis by the pitch bearing.

3. The rotor blade according to claim 2, wherein the pitch bearing has a sole bearing configured to absorb axial loads, radial loads, and tilt moments between the outer structure and the non-pitched carrier.

4. The rotor blade according to claim 1, wherein the pitch bearing has a first bearing and a second bearing, each configured to absorb loads.

5. The rotor blade according to claim 4, wherein the first bearing is spaced farther apart from the flange than the second bearing.

6. The rotor blade according to one of claim 1, further comprising a pitch plane that is spaced apart from the blade root toward the blade tip, wherein the pitch plane divides the rotor blade into a non-pitched part and a pitched part.

7. The rotor blade according to claim 2, wherein an overlap area is provided between the outer structure and the non-pitched carrier.

8. The rotor blade according to claim 7, further comprising a shaft end supported in the non-pitched carrier so as to be capable of being rotated by the pitch bearing, and is supported on the outer structure.

9. The rotor blade according to claim 7, wherein the non-pitched carrier is arranged inside the outer structure.

10. The rotor blade according to claim 9, comprising a blade covering that extends between the blade root and the outer structure substantially to the pitch plane.

11. A wind turbine, comprising: a generator, a rotor hub coupled to the generator, and at least one rotor blade fastened to the rotor hub, wherein the at least one rotor blade is the rotor blade according to claim 1.

12. The wind turbine according to claim 11, wherein the at least one rotor blade comprises a pitch drive comprising a comprising a drive pinion configured to engage with a gearing.

13. The wind turbine according to claim 12, wherein the gearing is arranged on an outer structure of the at least one rotor blade, on a shaft end provided on the outer structure, or directly on the pitch bearing.

14. The wind turbine according to claim 12, wherein the gearing is embodied along an angular range of between 60 and 270.

15. The wind turbine according to claim 12, wherein the gearing has a plurality of segments arranged in a row.

16. The wind turbine according to claim 11, wherein the generator is a synchronous generator.

17. The wind turbine according to claim 11, wherein the at least one rotor blade is a plurality of rotor blades.

18. The rotor blade according to claim 4, wherein the loads include at least one of: axial loads, radial loads, and tilt moments.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0030] FIG. 1 shows a schematic wind turbine in a first exemplary embodiment,

[0031] FIG. 2a shows a partial illustration of the wind turbine according to FIG. 1 comprising a rotor blade according to a first exemplary embodiment,

[0032] FIG. 2b shows a partial illustration of the wind turbine according to FIG. 1 comprising a rotor blade according to a second exemplary embodiment,

[0033] FIG. 3 shows a wind turbine according to the invention according to a preferred exemplary embodiment comprising a rotor blade according to the invention.

DETAILED DESCRIPTION

[0034] FIG. 1 shows a wind turbine 100 comprising a tower 102 and a nacelle 104. A rotor hub 106 comprising three rotor blades 1 and a spinner 110 is arranged on the nacelle 104. During operation, the rotor 106 is made to rotate by means of the wind and thus drives a generator in the nacelle 104.

[0035] FIG. 2a shows the rotor blade 1 according to FIG. 1 in a schematic partial sectional view. The rotor blade 1 has a blade root 3 and a blade tip 5. On the blade root side end, the rotor blade 1 has a flange 7 for fastening to the rotor hub 106.

[0036] The rotor blade 1 has a pitch bearing 9a. The pitch bearing 9a is spaced apart from the flange 7 at a distance A1. The pitch bearing 9a is preferably embodied as moment or (multi-row) four-point bearing. The pitch bearing 9a is fastened by a carrier 11 to an inner bearing ring. The carrier 11 has the flange 7 and is fixedly anchored to the rotor hub 106. On its outer ring, the pitch bearing 9a is fixedly connected to an outer structure 13, so that the outer structure 13 is supported so as to be capable of being rotated relative to the carrier 11 by means of the pitch bearing 9a. The pitch bearing 9a defines a pitch axis P, about which the rotor blade 1 or the outer structure 13 thereof, respectively, can be adjusted about the angle in the angle of attach.

[0037] In a preferred alternative, the pitch mounting additionally has a support bearing 9b, which is arranged on the carrier 11 at a distance A.sub.2 to the flange 7 and which additionally supports the outer structure 13.

[0038] The outer structure 13 is preferably embodied as a homogenous part, in the case of which an overlap area between the carrier 11 and the outer structure 13 results in the area 13b. In a preferred alternative, the outer structure 13 is embodied in several parts and has a first part 13a and a second part 13b, which are either coupled to one another or which are each coupled to one another by means of the bearing 9a.

[0039] In the area of an overlap between the outer structure 13 and the carrier 11, the pitch plane moves toward the blade root 3 in the direction of the flange 7 to the extent of the design of the overlap. In the shown exemplary embodiment of FIG. 2a, the pitch plane would be at the location identified by E.sub.2 in the case of an assumed homogenous outer structure 13, in which the areas 13a and 13b rotate.

[0040] The mode of operation of a pitch mounting according to the invention will be explained below under the assumption that the pitch mounting only has the pitch bearing 9a: On the one hand, the force F.sub.2 acts on the rotor blade in the area 13a of the outer structure, and the force F.sub.1 acts in the area 13b. The force F.sub.1 has a lever arm I.sub.1 to the pitch bearing 9a, while the force F.sub.2 has a lever arm I.sub.2 to the pitch bearing 9a. The resulting tilt moment M results according to the equation M=F.sub.2I.sub.2F.sub.1I.sub.1. In comparison, the resulting tilt moment would be significantly larger, if the pitch mounting were arranged directly on the flange 7. The moment would then result from the sum of the force F.sub.1 multiplied by its distance to the flange, and the sum F.sub.2 multiplied by its distance to the flange 7. It is immediately obvious that that resulting movement would be larger by a wind turbine multiple than the resulting tilt moment according to the invention.

[0041] The stability of the rotor blade 1 is additionally improved by the use of the additional pitch bearing 9b.

[0042] FIG. 2b shows an embodiment of a rotor blade 1, which is an alternative to FIG. 2a, for a wind turbine 100. In that embodiment, in which only the area 13a acts as outer structure, the carrier 11 is no longer embodied as being located on the inside, but as hollow body being located on the outside and preferably acts as blade coating 16 on the outside between the pitch plane E and the blade root. The outer structure 13a has a shaft end 14, which is rotatably supported in the carrier 11. The area 13a is the pitched part of the rotor blade, while a part 13c, which is not pitched, is embodied between pitch plane E and the flange 7.

[0043] In the exemplary embodiment according to FIGS. 2a, b, the pitch axis P corresponds approximately to a longitudinal axis of the rotor blade, which extends from the middle of the blade root 3 to the middle of the blade tip 5.

[0044] In the exemplary embodiment shown in FIG. 3, this is somewhat different. FIG. 3 also illustrates a wind turbine 100 according to the invention, but comprising a rotor blade 1, which differs from the illustration according to FIG. 2. The rotor blade 1 also has a blade root 3 and a blade tip 5. A flange 7 is embodied on a carrier 11 and is connected to the rotor hub 106. The outer structure 13 of the rotor blade 1 can also be adjusted by an angle about the pitch axis P. The rotor blade 1 is divided into a non-pitched part 13a and a pitched part 13c by means of the (non-illustrated) pitch mounting in a pitch plane E, wherein, as a result of the nonexistent overlap, the non-pitched part is characterized by the carrier 11, and the pitched part by the outer structure 13.

[0045] The significant difference to the illustration according to FIG. 2 is that the carrier 11, which has a carrier axis Z, is angled with the carrier axis Z by an angle relative to the pitch axis P, so that the outer structure 13 and the pitch axis P are spaced apart farther from a vertical axis T of the tower 102 of the wind turbine 100 than the flange 7 on the blade root side end of the rotor blade 1. As a result of this angle a, the rotor blades 1 are moved away farther from the vertical axis T of the tower 102 of the wind turbine 100, whereby the free travel F of the tower is increased while the rotor blade length remains the same or the rotor blade 1 can be embodied so as to be longer until reaching a minimally prescribed free travel of the tower, respectively. As a result of the design according to the invention, a highly compact nacelle or machine housing size, respectively, is additionally attained, suggested by reference numeral 104.

[0046] It follows from the above discussions that a wind turbine, which is improved in its function load situation, can be attained by complying with the aspects according to the invention.