METHOD FOR CONNECTING TWO WIND TURBINE BLADE PORTIONS, METHOD FOR PRODUCING A WIND TURBINE, AND METHOD FOR CONNECTING TWO MOLDED PORTIONS

Abstract

Provided is a method for connecting two wind turbine blade portions, the method including the steps of: a) providing) a first wind turbine blade portion and a second wind turbine blade portion, b) providing a plurality of first markers on the first blade portion and providing a plurality of second markers on the second blade portion, c) determining of target positions of the first markers and the second markers, d) aligning the wind turbine blade portions to each other and comparing actual positions of the first markers and the second markers with the target positions, and e) connecting the wind turbine blade portions together. Therefore, a shape accuracy of a wind turbine blade can be improved.

Claims

1. A method for connecting two wind turbine blade portions, the method comprising the steps of: a) providing) a first wind turbine blade portion and a second wind turbine blade portion, b) providing a plurality of first markers on the first blade portion and providing a plurality of second markers on the second blade portion, c) determining of target positions of the first markers and the second markers, d) aligning the wind turbine blade portions to each other and comparing actual positions of the first markers and the second markers with the target positions, and e) connecting the wind turbine blade portions together.

2. The method according to claim 1, wherein in step a) the first wind turbine blade portion is molded by a first mold and the second wind turbine blade portion is molded by a second mold.

3. The method according to claim 2, wherein step b) is executed when the first wind turbine blade portion is in at least one of the first mold and the second wind turbine blade portion is in the second mold.

4. The method according to claim 1, wherein initial positions of the first and the second markers are determined during or immediately after step b).

5. The method according to claim 4, wherein the target positions of the first markers and/or the second markers are determined by the initial positions of at least one of the first markers and the second markers.

6. The method according to claim 5, wherein the target positions of the first markers and the second markers are determined by setting a relation between the initial position of the first markers relative to the initial positions of the second markers.

7. The method according to claim 1, wherein the actual positions of the first and/or the second markers are detected during step d) by detecting means or detector.

8. The method according to claim 1, wherein step d) is executed by digital image correlation.

9. The method according to claim 1, wherein step d) is executed by a carrying device which is configured to move the first wind turbine blade portion in at least 3, 4, 5 or 6 degrees of freedom relative to the second wind turbine blade portion.

10. The method according to claim 9, wherein the carrying device is configured to move the second wind turbine blade portion in at least 3, 4, 5 or 6 degrees of freedom relative to the first wind turbine blade portion.

11. The method according to claim 1, wherein in step d) and/or e) leading edges of the first and the second wind turbine blade portions face downward or upward.

12. The method according to claim 1, wherein the first and the second markers are digitally generated points and/or concretely created on the respective wind turbine blade portion.

13. The method according to claim 1, wherein the first wind turbine blade portion and the second wind turbine blade portion are longitudinal segments of a wind turbine blade.

14. A method for producing a wind turbine, the method comprising the steps of: a2) connecting two wind turbine blade portions according to the method of claim 1 such that a wind turbine blade is provided, and b2) connecting the wind turbine blade to a hub of the wind turbine.

15. A method for connecting two molded portions, the method comprising the steps of: a3) molding a first portion by a first mold and a second portion by a second mold, b3) providing first markers on the first portion when the first portion is in the first mold and second markers on the second portion when the second portion is in the second mold, and c3) connecting the first and the second portions together by the first and the second markers.

Description

BRIEF DESCRIPTION

[0046] Some of the embodiments will be described in detail, with references to the following Figures, wherein like designations denote like members, wherein:

[0047] FIG. 1 shows a perspective view of a wind turbine according to one embodiment;

[0048] FIG. 2 shows a perspective view of a wind turbine blade of the wind turbine according to FIG. 1;

[0049] FIG. 3 shows a perspective view of a first and a second wind turbine blade portion each lying in a mold;

[0050] FIG. 4 shows a perspective view of the first and the second wind turbine blade portion carried by a carrying device;

[0051] FIG. 5 shows a perspective view of a support structure of the carrying device;

[0052] FIG. 6 shows a schematical side view of the support structure;

[0053] FIG. 7 shows a perspective view of the first and the second wind turbine blade portion when aligning the same to each other;

[0054] FIG. 8 shows a block diagram of a method for connecting two wind turbine blade portions;

[0055] FIG. 9 shows a block diagram of a method for producing a wind turbine; and

[0056] FIG. 10 shows a block diagram of a method for connecting two molded portions.

DETAILED DESCRIPTION

[0057] FIG. 1 shows a wind turbine 1. The wind turbine 1 comprises a rotor 2 connected to a generator (not shown) arranged inside a nacelle 3. The nacelle 3 is arranged at an upper end of a tower 4 of the wind turbine 1.

[0058] The rotor 2 comprises three blades 5 (i.e. wind turbine blades). The blades 5 are connected to a hub 6 of the wind turbine 1. Rotors 2 of this kind may have diameters ranging from, for example, 30 to 300 meters or even more. The blades 5 are subjected to high wind loads. At the same time, the blades 5 need to be lightweight. For these reasons, blades 5 in modern wind turbines 1 are manufactured from fiber-reinforced composite materials, e.g. by means of casting. Oftentimes, glass or carbon fibers in the form of unidirectional fiber mats are used. Such blades 5 may also include woods and other reinforcement materials.

[0059] FIG. 2 shows the blade 5. The blade 5 comprises an aerodynamically designed portion 7 which is shaped for optimum exploitation of the wind energy and a blade root 8 for connecting the blade 5 to the hub 6. Further, the blade 5 comprises a blade tip 9 which faces away from the blade root 8. The blade 5 extends in a longitudinal direction L which points from the blade root 8 towards the blade tip 9. The blade 5 has a length M which, for example, may be between 15 to 100 m or even more. The wind turbine blade 5 comprises a leading edge 10 and a trailing edge 11.

[0060] FIG. 3 shows a perspective view of a blade portion 12 (also referred as first blade portion) and a blade portion 13 (also referred as second blade portion). The blade portion 12 comprises the blade tip 9 and the blade portion 13 comprises the blade root 8. Further, the blade portion 12 comprises a connecting surface 23 and the blade portion 13 comprises a connecting surface 24. The blade portions 12, 13 are configured to be connected at together the connecting surfaces 23, 24. For example, the connecting surfaces 23, 24 run essentially perpendicular to the longitudinal direction L. The blade portions 12, 13 are longitudinal segments of the blade 5 (see e.g. FIG. 2).

[0061] The blade portion 12 is casted by means of a mold 14 (also referred as first mold) and the blade portion 13 is casted by means of a mold 15 (also referred as second mold). The mold 14 is a multi-part mold comprising a lower mold part 16 and an upper mold part (not shown). For example, the upper mold part may be removed after molding the blade portion 12 as shown in FIG. 3. The mold 15 is a multi-part mold comprising a lower mold part 17 and an upper mold part (not shown).

[0062] This has the advantage that the blade portions 12, 13 may be accessible after molding without removing the blade portion 12, 13 from the lower mold part 16, 17. The mold 14 comprises a hollow space 18 having a negative form of the blade portion 12. In particular, the mold 15 comprises a hollow space (not shown) having a negative form of the blade portion 13.

[0063] As shown in FIG. 3 an outer surface 19 of the blade portion 12 is exposed. Markers 20 (also referred as first markers) are provided on the surface 19. Further, an outer surface 21 of the blade portion 13 is exposed. Markers 22 (also referred as second markers) are provided on the surface 21. The markers 20, 22 can be set when the blade portions 12, 13 lie in the molds 14, 15. Therefore, a large contact surface between the blade portions 12, 13 and the molds 14, 15 is provided.

[0064] This has the advantage that the blade portions 12, 13 are substantially stressless and, thus, undeformed.

[0065] After providing the markers 20, 22 initial positions of the markers 20, 22 may be determined, e.g. by means of measuring and recording the same. Further, target positions of the markers 20, 22 may be determined by setting a relation between the initial position of the markers 20 relative to the initial positions of the markers 22.

[0066] Alternatively, or additionally, the target positions are determined by means of computer generated positions. For example, the initial positions can be combined with computer generated positions of the markers 20, 22 for obtaining the target positions of the markers 20, 22. The markers 20, 22 may be digitally generated points and/or concretely provided or created on the surface 19, 21. In particular, 2-30, 3-10, 3-7, or 4 to 5 markers 20 are provided. For example, 2-30, 3 10, 3-7, or 4 to 5 markers 22 are provided. The markers 20 and/or the markers 22 may be arranged in at least two rows along the longitudinal direction L.

[0067] FIG. 4 shows a perspective view of the blade portions 12, 13. The blade portions 12, 13 are carried by a carrying device 25. The carrying device 25 is configured to move the blade portion 12 in at least 3, 4, 5 or 6 degrees of freedom relative to the blade portion 13. In particular, the carrying device 25 is configured to move the blade portion 12 in longitudinal direction L and/or in height direction H and/or in side direction Y which is perpendicular to the height direction H and the longitudinal direction L. The carrying device 25 is configured to rotate or tilt the blade portion 12 around the longitudinal direction L and/or the height direction H and/or the side direction Y.

[0068] The carrying device 25 may comprise a support structure 26, in particular a trolley or yoke, configured to support the blade portion 12 at one contact surface 27 and a support structure 28, in particular a trolley or yoke, configured to support the blade portion 12 at another contact surface 29. More support structures 30, 31, 32, in particular trolleys or yokes, are provided for supporting the blade portion 12.

[0069] The carrying device 25 may also be configured to move the blade portion 13 in at least 3, 4, 5 or 6 degrees of freedom relative to the blade portion 12. In particular, the carrying device 25 is configured to move the blade portion 13 in longitudinal direction L and/or in height direction H and/or in side direction Y which is perpendicular to the height direction. The carrying device 25 is configured to rotate or tilt the blade portion 13 around the longitudinal direction L and/or the height direction H and/or the side direction Y. The carrying device 25 may comprise a support structure 33, in particular a trolley or yoke, configured to support the blade portion 13 at one contact surface 34 and a support structure 35, in particular a trolley or yoke, configured to support the blade portion 13 at another contact surface 36.

[0070] FIG. 5 shows a perspective view of the support structure 26 of the carrying device 25. The support structure 26 comprises a frame 37 to which wheels 38 are connected. Further, a motor 39 may be provided for driving the support structure 26 by means of the motor 39. The support structure 26 is, thus, configured to move in longitudinal direction L (see e.g. FIG. 7).

[0071] Further, the support structure 26 comprises a receptacle 40 for receiving the blade portion 12. The receptacle 40 interacts with the contact surface 27 of the blade portion 12 (see FIG. 4) by means of arc shaped surfaces 41 which are provided at, in particular movable, holding shells 42, 43. Each shell 42, 43 may be arc shaped. The holding shells 42, 43 may be arranged side by side forming a V-shape or U-shape.

[0072] FIG. 6 shows a schematical side view of the carrying device 26. The support structure 26 comprise a lifting system 44, in particular a lifting platform, for lifting the receptacle 40 and the blade portion 12 (see e.g. FIG. 7) in height direction H. The lifting system 44 may comprise a hydraulic or pneumatic mechanism (not shown) or an electric motor for lifting.

[0073] For example, actuators 45 for adjusting a tilt angle of each shell 42, 43 may be provided. The actuators 45 may be hydraulic, pneumatic or electric actuators. The actuators 45 and the shells 42, 43 may be comprised by a tilt system 46 for tilting and/or twisting the blade portion 12. All support structures 26, 28, 30, 31, 30, 33, 35 may be designed as described for support structure 26.

[0074] FIG. 7 shows a perspective view of the blade portions 12, 13 when aligning the same to each other. The carrying device 25 comprises a control unit 47 to which all support structures 26, 28, 30, 31, 30, 33, 35 are (e.g. electrically and/or by means of communication means or a communicator) connected. Further, the control unit 47 may be connected to a computer 48. Furthermore, detecting means 49 may be provide for detecting the actual positions of the markers 20, 22. This has the advantage that an exact alignment between the blade portions 12, 13 can be controlled.

[0075] The detecting means comprise sensors and/or a cameras 50, in particular exactly two cameras 50. The detecting means 49 may be connected to the computer 48 and/or the control unit 47. Digital image correlation is applied for measuring the actual positions of the markers 20, 21 and/or a movement of the markers 20, 21. As shown in FIGS. 4 and 7 the leading edges 10 of the blade portions 12, 13 face downward. However, the leading edges 10 of the blade portions 12, 13 may face upward. When the support structures 26, 28, 30, 31, 30, 33, 35 are correctly piloted such that the blade portions 12, 13 are aligned, the blade portions 12, 13 can be connected together.

[0076] FIG. 8 shows a block diagram of a method for connecting two blade portions 12, 13. In a step S1 the blade portion 12 and the blade portion 13 are provided. The blade portions may be provided by means of casting. In a step S2 a plurality of markers 20 are provided on the blade portion 12 and a plurality of markers 22 are provided on the blade portion 13. In an optional step S3 initial positions (e.g. when the blade portions lie in the molds 14, 15, see FIG. 3) of the markers 20, 22 are determined. Alternatively, or additionally the markers 20, 22 are provided at predetermined positions at the blade portions 12, 13.

[0077] In a step S4 target positions of the markers 20, 22 are determined. This can be executed by means of calculating the target positions for a connected blade 5, wherein the initial positions obtained in step S3 may be used as input values. In a step S5 detecting means 49 are provided for detecting actual positions of the markers 20, 22.

[0078] In a step S6 the blade portions 12, 13 are aligned to each other and the actual positions of the markers 20, 22 are compared with the target positions until an acceptable deviation is obtained. In a step S7 the blade portions 12, 13 are connected together. In particular, the actual positions of the markers 20, 21 are detected by the detecting means 49 during step S7.

[0079] FIG. 9 shows a block diagram of a method for producing a wind turbine. In a steps S11 the blade which is ready to mount is provided, wherein the blade 5 is provided by the method for connecting two wind turbine blade portions 12, 13 (see FIG. 8). In a step S12 the tower 4 is provided and sited. In a step S13 a nacelle 3 and a hub 6 are connected to the tower 4. In a step S14 a blade 5 is connected to the hub 6 of the wind turbine 1.

[0080] FIG. 10 shows a block diagram of a method for connecting two molded portions 12, 13. In a step S21 a portion 12 is molded by means of a mold 14 and a portion 13 is molded by means of a mold 15. In a step S22 markers 20 are provided (e.g. set) on the portion 12 when the portion 12 is (e.g. lies) in the mold 14 and markers 22 are provided (e.g. set) on the portion 13 when the portion 13 is (e.g. lies) in the mold 15. In a step S23 portions 12, 13 are connected together by means of the markers 20, 22 to form a component, in particular a blade 5. Therefore, a shape accuracy of two connected portions can be improved.

[0081] The features explained with reference to FIG. 1-7 apply mutatis mutandis to the methods of FIG. 8-10.

[0082] Although the present invention has been disclosed in the form of preferred embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0083] For the sake of clarity, it is to be understood that the use of a or an throughout this application does not exclude a plurality, and comprising does not exclude other steps or elements.