METHOD FOR PRODUCING A WIND TURBINE BLADE AND WIND TURBINE BLADE

Abstract

Disclosed is a wind turbine blade and a method for its manufacture. A lower shell part and an upper shell part are provided, each shell part having a leading edge end and a trailing edge end. A flatback profile component and web for connecting an inner surface of the lower side shell part with an inner surface of the upper side shell part are connected. The assembly which comprises the flatback profile component and the at least one web are placed on the lower shell part and the upper shell part is mounted. The wind turbine blade comprises a flatback profile component being arranged at the trailing edge, wherein the flatback profile component is coupled by at least one distance holder with at least one web, wherein the web couples the interior surface of the upwind side shell part with the interior surface of the downwind side shell part.

Claims

1. A method of manufacturing a wind turbine blade, which comprises a flatback profile at its trailing edge, said method comprising: providing a lower shell part and an upper shell part, each shell part having a leading edge end and a trailing edge end, providing a flatback profile component, providing at least one web for connecting an inner surface of the lower shell part with an inner surface of the upper shell part, connecting the flatback profile component with the at least one web to form a flatback assembly, placing the flatback assembly on the lower shell part, mounting the upper shell part on the lower shell part and on the flatback assembly.

2. The method according to claim 1, wherein the flatback profile component comprises one or more flanges, wherein an adhesive is applied on the one or more flanges of the flatback profile component and wherein the flatback profile component is bonded to the trailing edge ends of the lower and upper blade shell part.

3. The method according to claim 1, wherein in the flatback assembly, the at least one web is connected with a least one further web, in particular with a leading edge web.

4. The method according to claim 1, wherein the at least one web is connected with the flatback profile component and/or a further web by distance holders, in particular by bolts.

5. The method according to claim 4, wherein plastic bolts are used as distance holders.

6. The method according to claim 1, wherein a flatback profile component is provided, which has a varying geometry over its length.

7. The method according to claim 1, wherein a flatback component with angled flanks is provided, which are bonded with the leading and the trailing edge of the blade shell parts.

8. The method according to claim 1, wherein the flatback assembly is lifted into the lower blade shell part when the lower shell part is arranged in a mould, and wherein the mould is closed in order to bond the upper shell part with the lower shell part.

9. The method according to claim 1, wherein said flatback profile component is connected with the at least one web by at least two bolts, wherein the bolts are arranged above each other.

10. A wind turbine blade obtainable by a method according to claim 1, said wind turbine blade comprising: an upwind side shell part, a downwind side shell part, a leading edge and a trailing edge, a flatback profile component being arranged at the trailing edge, wherein the flatback profile component is coupled by at least one distance holder with at least one web, wherein the web couples the interior surface of the upwind side shell part with the interior surface of the downwind side shell part.

11. The wind turbine blade according to claim 10, wherein a side face of the web is connected with the flatback web component by bolts, in particular by plastic bolts.

12. The wind turbine blade according to claim 10, wherein the at least one web is embodied as an I-beam profile, wherein the I-beam profile is bonded by an adhesive to the interior surfaces of the blade shell parts.

13. The wind turbine blade according to claim 10, wherein the wind turbine blade comprises a first web being arranged in a trailing edge region and a second web being arranged in arranged in a leading edge region, wherein the first web is coupled by the at least one distance holder with the flatback profile component and wherein the first web is coupled with the second web by at least one further distance holder.

14. The wind turbine blade according to claim 10, wherein the flatback profile component comprises a fibre reinforced laminate.

15. A flatback assembly for use in a wind turbine blade according to claim 10, the flatback assembly comprising a flatback profile component and at least one shear web, wherein the flatback profile component is connected with the at least one shear web to form the flatback assembly.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0063] Embodiments of the disclosure of the invention will be described in more detail in the following with regard to the accompanying figures. The figures show one way of Implementing the present invention and are not to be construed as being limiting to other possible embodiments falling within the scope of the attached claim set.

[0064] FIG. 1 is a schematic diagram illustrating an exemplary wind turbine,

[0065] FIG. 2 is a schematic diagram illustrating an exemplary wind turbine blade,

[0066] FIG. 3 shows a wind turbine blade with a flatback profile at the trailing edge in more detail,

[0067] FIG. 4 is a schematic view of an assembly with a flatback profile component and shear webs, which is used for manufacturing the wind turbine blade,

[0068] FIG. 5 is a schematic illustration, how the assembly with the flatback profile component and the shear webs are arranged in the wind turbine blade.

[0069] FIG. 6 is flowchart of an exemplary method for manufacturing a wind turbine blade.

DETAILED DESCRIPTION

[0070] FIG. 1 illustrates a conventional modern upwind wind turbine 2 according to the so-called “Danish concept” with a tower 4, a nacelle 6 and a rotor with a substantially horizontal rotor shaft. The rotor includes a hub 8, and three blades 10 extending radially from the hub 8, each having a blade root 16 nearest the hub and a blade tip 14 furthest from the hub 8.

[0071] FIG. 2 shows a schematic view of an exemplary wind turbine blade 10. The wind turbine blade 10 has the shape of a conventional wind turbine blade with a root end 17 and a tip end 15 and comprises a root region 30 closest to the hub, a profiled or an airfoil region 34 furthest away from the hub and a transition region 32 between the root region 30 and the airfoil region 34. The blade 10 comprises a leading edge 18 facing the direction of rotation of the blade 10, when the blade is mounted on the hub, and a trailing edge 20 facing the opposite direction of the leading edge 18.

[0072] The airfoil region 34 (also called the profiled region) has an ideal or almost ideal blade shape with respect to generating lift, whereas the root region 30 due to structural considerations has a substantially circular or elliptical cross-section, which for instance makes it easier and safer to mount the blade 10 to the hub. The diameter (or the chord) of the root region 30 may be constant along the entire root area 30. The transition region 32 has a transitional profile gradually changing from the circular or elliptical shape of the root region 30 to the airfoil profile of the airfoil region 34. The chord length of the transition region 32 typically increases with increasing distance r from the hub. The airfoil region 34 has an airfoil profile with a chord extending between the leading edge 18 and the trailing edge 20 of the blade 10. The width of the chord decreases with increasing distance r from the hub.

[0073] A shoulder 40 of the blade 10 is defined as the position, where the blade 10 has its largest chord length. The shoulder 40 is typically provided at the boundary between the transition region 32 and the airfoil region 34.

[0074] It should be noted that the chords of different sections of the blade normally do not lie in a common plane, since the blade may be twisted and/or curved (i.e. pre-bent), thus providing the chord plane with a correspondingly twisted and/or curved course, this being most often the case in order to compensate for the local velocity of the blade being dependent on the radius from the hub.

[0075] The wind turbine blade 10 comprises a blade shell may comprise two blade shell parts, a first blade shell part 24 and a second blade shell part 26, typically made of fibre-reinforced polymer. The first blade shell part 24 is typically a pressure side or upwind blade shell part. The second blade shell part 26 is typically a suction side or downwind blade shell part. The first blade shell part 24 and the second blade shell part are typically glued together along bond lines or glue joints 28 extending along the trailing edge 20 and the leading edge 18 of the blade 10. Typically, the root ends of the blade shell parts 24, 26 have a semi-circular or semi-oval outer cross-sectional shape.

[0076] The trailing edge 20 may be embodied as a flatback trailing edge, wherein the edge is flattened in order to achieve better aerodynamic properties. This construction increases the efficiency of the wind turbine blade in comparison with a sharp edge design.

[0077] FIG. 3 shows a wind turbine blade 10 with a flatback profile at the trailing edge in more detail. The trailing edge 20 has a flattened profile. The flattened profile increases the aerodynamic efficiency and also helps to reduce the chord width.

[0078] The flatback profile Is provided by a flatback profile component 30 which connects the upwind side shell part 24 to the downwind side shell part 26. Details of this flatback profile component 30 and the method for manufacturing the wind turbine blade 10 will be explained in more detail with reference to the following drawings.

[0079] FIG. 4 is a schematic view of an assembly 70 with a flatback profile component and shear webs, which is used for manufacturing the wind turbine blade.

[0080] The flatback profile component 30, which is to be bonded with the blade shell parts is connected with at least one web 50 by plastic bolts 40, which are arranged between a side face of the web 50 and the flatback profile component 30.

[0081] According to this embodiment of the invention, the web 50 is connected by plastic bolts 41 with a second web 60.

[0082] The webs 50, 60 are embodied as shear webs, which extend along a longitudinal length of the wind turbine blade.

[0083] The flatback profile component 30 is embodied as a panel which is to be bonded with the blade shell parts to form at least part of the trailing edge of the blade.

[0084] In order to manufacture the wind turbine blade, adhesive may be applied on the flanks 31 of the flatback profile component 30 and on the lower and upper surfaces 51, 61 of the webs 50, 60. The entire assembly 70 may be positioned in a lower blade shell, and the manufacturing of the wind turbine blade may be finished by closing a mould in order to combine upper and lower blade shell part.

[0085] FIG. 5 is a schematic illustration of how the assembly with the flatback profile component 30 and the shear webs 50, 60 is arranged in the wind turbine blade 10.

[0086] The web 60 is embodied as a leading edge shear web, which is arranged next to the leading edge 18 of the wind turbine blade.

[0087] The web 50 serves as a trailing edge shear web, which is arranged next to the trailing edge 20, which is embodied as a flatback trailing edge being provided by the flatback profile component 30.

[0088] The flatback profile component 30 is connected to the web 50 by bolts 40, and the web 50 is connected to the second web 60 by bolts 41. Preferably, at least two rows of bolts 40 and two rows of bolts 41 are arranged in a stacked manner in order to prevent a distortion of the components.

[0089] The bolts 40, 41 may the bonded with an adhesive to the side face of the web 50, 60 or the flatback profile component 30, respectively. The bolts 40, 41 may also be inserted into blind holes or through holds provided in the web 50, 60 and/or in the flatback profile component 30.

[0090] The flatback profile component 30 is embodied as a panel with a varying geometry over its length, and comprises, at least sectionwise, angled flanks 31, which are bonded to the exterior surfaces of the blade shell parts.

[0091] FIG. 6 is a flowchart showing the steps of producing a wind turbine blade according to an embodiment of the invention.

[0092] A lower shell part and an upper shell part are produced, each shell part having a leading edge end and a trailing edge end 100.

[0093] A flatback profile component and at least one web for connecting an inner surface of the lower side shell part with an inner surface of the upper side shell part are manufactured separately 101, and the flatback profile component is connected with the at least one web 102.

[0094] This assembly, which comprises the flatback profile component and the at least one web, is lifted into a lower shell part (e.g. Into the upwind side shell part), when the lower shell part is arranged in a mould 103.

[0095] Finally, the mould for combining the blade shell parts is closed 104.

[0096] Due to the fact that the entire assembly with webs 50, 60 and flatback profile component 30 can be assembled offline and lifted as one component into the lower shell part, the manufacturing of the wind turbine blade is faster and easier to perform with a high accuracy.

[0097] The invention has been described with reference to preferred embodiments. However, the scope of the invention is not limited to the Illustrated embodiments, and alterations and modifications can be carried out without deviating from the scope of the invention.

LIST OF REFERENCES

[0098] 2 wind turbine [0099] 4 tower [0100] 6 nacelle [0101] 8 hub [0102] 10 blade [0103] 11 groove [0104] 14 blade tip [0105] 15 tip end [0106] 16 blade root [0107] 17 root end [0108] 18 leading edge [0109] 20 trailing edge [0110] 24 first/lower blade shell part (upwind/pressure side shell part) [0111] 26 second/upper blade shell part (downwind/suction side part) [0112] 30 flatback profile component [0113] 31 flank [0114] 40 bolt [0115] 41 bolt [0116] 50 web (trailing side) [0117] 51 surface [0118] 60 web (leading side) [0119] 61 surface [0120] 70 assembly of flatback profile component and web [0121] 100 providing a lower shell part and an upper shell part, each shell part having a leading edge end and a trailing edge end [0122] 101 providing a flatback profile component and at least one web for connecting an Inner surface of the lower side shell part with an Inner surface of the upper side shell part [0123] 102 connecting the flatback profile component with the at least one web [0124] 103 lifting the assembly, which comprises the flatback profile component and the at least one web into the lower shell part, wherein the lower shell part is arranged in a mould [0125] 104 closing the mould in order to combine the shell parts