Tower arrangement for a wind turbine, wind turbine comprising the tower arrangement and method for erecting a wind turbine

Abstract

A tower arrangement for a wind turbine, including: a guyed tower, cable foundations each including a through-hole, one or more stay cables, each stay cable being anchored at its first end at the tower and being anchored at its second end at one of the cable foundations, and one or more anchoring means for anchoring the second end of each stay cable at the respective cable foundation, wherein each stay cable is guided through a respective through-hole and anchored, with respect to its first end, behind the respective through-hole at its second end using the anchoring means is provided. By having the cable foundations comprising the through-holes, guiding the stay cables through the through-holes and anchoring them behind the through-holes, external connection means such as steel structures poured into the concrete foundation are not required. Thus, the anchoring of the stay cables at the cable foundations is simplified.

Claims

1. A tower arrangement for a wind turbine, comprising: a guyed tower; one or more cable foundation blocks each including a through-hole, the one or more cable foundation blocks having at least a front side and a back side; one or more stay cables, each stay cable being anchored at a first end at the guyed tower and being anchored at a second end by one of the one or more cable foundation blocks; and one or more anchoring means disposed at the back side of the one or more cable foundation blocks for anchoring the second end of each stay cable at a respective cable foundation block; wherein each stay cable is guided through a respective through-hole of the respective cable foundation block and anchored, with respect to the first end, behind the respective through-hole at the second end using the one or more anchoring means, the one or more anchoring means engaging the back side of the respective cable foundation block behind the respective through-hole.

2. The tower arrangement according to claim 1, wherein each of the one or more anchoring means engage with the respective cable foundation block in a form fit.

3. The tower arrangement according to claim 1, wherein each of the one or more anchoring means include an anchoring plate, and a size of the one or more anchoring plates is larger than a diameter of the through-hole of the respective cable foundation block.

4. The tower arrangement according to claim 1, wherein one, several or all of the one or more anchoring means include means to compensate for a misalignment between an axis of a through-hole and an axis of a respective stay cable.

5. The tower arrangement according to claim 1, wherein each of the one or more anchoring means includes an anchoring plate, and each anchoring plate includes two plate surfaces being parallel to each other or inclined to each other by an angle of at least 0.5, 1, 2, 3, 4 and/or 5.

6. The tower arrangement according to claim 1, wherein: one, several or all of the one or more anchoring means include a spherical washer, a mating concave nut and an anchoring plate; the spherical washer is arranged, with respect to the first end of the respective stay cable, behind the anchoring plate with a spherical surface of the spherical washer facing the anchoring plate; and the mating concave nut is arranged between the spherical washer and the anchoring plate such that a concave surface of the mating concave nut engages with the spherical surface of the spherical washer.

7. The tower arrangement according to claim 1, wherein each stay cable comprises at its second end a cable head including a flange resting against the anchoring means.

8. The tower arrangement according to claim 1, wherein one, several or all of the one or more cable foundations are arranged above ground or at least partly below ground.

9. The tower arrangement according to claim 1, wherein one, several or all of the one or more cable foundations include a cavity accommodating the respective anchoring means and the second end of the respective stay cable.

10. The tower arrangement according to claim 1, wherein the one or more cable foundation blocks are a concrete block or a reinforced concrete block containing metal.

11. The tower arrangement according to claim 1, wherein the one or more cable foundation blocks have a shape selected from the group consisting of: a cuboid, a cube, a cylinder, and a parallelepiped.

12. The wind turbine comprising a tower arrangement according to claim 1.

13. A method for erecting a wind turbine, comprising: a) providing an erected tower or tower section; b) connecting at least one stay cable at a first end to the erected tower or tower section; c) providing at least one cable foundation block including a through-hole; d) guiding each stay cable through the through-hole of a respective cable foundation block; and e) anchoring each stay cable at a second end, with respect to the first end, behind the respective through-hole using anchoring means that engages a back side of the respective cable foundation block behind the respective through-hole.

14. The method according to claim 13, further comprising compensating for a misalignment between an axis of a through-hole and an axis of a respective stay cable.

15. The method according to claim 14, wherein one or more of the anchoring means include an anchoring plate having two plate surfaces, and wherein the step of compensating for a misalignment includes selecting the respective anchoring plate from a group comprising an anchoring plate whose two plate surfaces are parallel to each other and anchoring plates whose two plate surfaces are inclined to each other by an angle of at least 0.5, 1, 2, 3, 4 and 5.

16. The method according to claim 14, wherein one or more of the anchoring means include an anchoring plate, a spherical washer and a mating concave nut, and wherein the step of compensating for a misalignment includes engaging, for a respective anchoring means, a spherical surface of the spherical washer with a concave surface of the mating concave nut such that an angle between an axis of the spherical washer and an axis of the mating concave nut is adjusted.

Description

BRIEF DESCRIPTION

(1) Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein:

(2) FIG. 1 depicts a wind turbine according to an embodiment;

(3) FIG. 2 depicts a tower arrangement of the wind turbine of FIG. 1;

(4) FIG. 3 depicts a detailed view of a cable foundation and a stay cable of the tower arrangement of FIG. 2 according to a first embodiment;

(5) FIG. 4 depicts a detailed view of the stay cable of FIG. 3 close to its second end;

(6) FIG. 5 depicts a detailed view of a cable foundation and a stay cable of the tower arrangement of FIG. 2 according to a second embodiment;

(7) FIG. 6 depicts a cable foundation of FIG. 2 partly arranged below ground;

(8) FIG. 7 depicts a misalignment between an axis of a through-hole of a cable foundation and an axis of a stay cable guided through the through-hole;

(9) FIG. 8 depicts a first example for compensating for a misalignment between the axis of the through-hole and the axis of the stay cable;

(10) FIG. 9 depicts a second example for compensating for a misalignment between the axis of the through-hole and the axis of the stay cable; and

(11) FIG. 10 depicts a flowchart illustrating a method for erecting the wind turbine of FIG. 1.

DETAILED DESCRIPTION

(12) In the Figures, like reference numerals designate like or functionally equivalent elements, unless otherwise indicated.

(13) FIG. 1 shows a wind turbine 1 according to an embodiment.

(14) The wind turbine 1 comprises a rotor 2 having, for example, three rotor blades 3. The rotor blades 3 are connected to a hub 4 of the wind turbine 1. The rotor 2 is connected to a generator (not shown) arranged inside a nacelle 5. The nacelle 5 is arranged at the upper end of a tower 6 of the wind turbine 1. The nacelle 5 is connected to the tower 6, for example by a yaw bearing (not shown) such that the nacelle 5 can rotate relative to the tower 6. The tower 6 is, for example, erected on a monopile 7 founded in the ground. The wind turbine 1 is, in particular, an onshore wind turbine.

(15) The wind turbine 1 converts the wind's kinetic energy into electrical energy. The higher the hub 4, i.e. the higher the tower 6, the more electrical energy can be generated with a wind turbine at a given wind harvesting site.

(16) The tower 6 has, for example, a height of 120-180 meters. The tower 6 comprises, for example, several tower sections such as the tower sections 8, 9, 10 shown schematically in FIG. 1. The tower 6 is a guyed tower comprising stay cables 11. Each stay cable 11 is tethered between the tower section 9 and a respective cable foundation 12.

(17) In particular, each stay cable 11 is connected at its first end 13 to the tower section 9 providing a first anchoring point 14 for the stay cable 11. The connection of the stay cables 11 to the tower section 9 is performed in a known way.

(18) Further, each stay cable 11 is connected at its second end 15 to the cable foundation 12 providing a second anchoring point 16 for the stay cable 11.

(19) The connection of the second end 15 of the stay cables 11 to the cable foundations 12 is described in the following.

(20) FIG. 2 shows a tower arrangement 17, 117. The tower arrangement 17, 117 comprises the guyed tower 6, three cable foundations 12, 112, three stay cables 11 and three anchoring means 18, 118, 218 for anchoring the second end 15 of each stay cable 11 at the respective cable foundation 12, 112. In FIG. 2, only one of the three anchoring means 18, 118, 218 is shown and denoted with a reference sign.

(21) In the example of FIG. 2, the cables foundations 12, 112 are arranged above the ground 19. However, the cables foundations may also be arranged (partly) below the ground 19 (FIG. 6).

(22) FIG. 3 shows a detailed view of one of the cable foundations 12 according to a first embodiment. Further, one of the stay cables 11 anchored to this cable foundation 12 is shown.

(23) The cable foundations 12 are made, for example, from concrete, e.g., reinforced concrete.

(24) Each cable foundation 12 comprises an elongated through-hole 20 to accommodate a portion 21 of the respective stay cable 11. The through-hole 20 has, for example, a circular cross-section. The through-hole 20 comprises an entrance opening 22 where the respective stay cable 11 extending from the tower 6 (FIG. 2) enters the through-hole 20. Further, the through-hole 20 comprises an exit opening 23 behind which the stay cable 11 is anchored by means of the anchoring means 18. The anchoring means 18 in this example is an anchoring plate 18.

(25) The cable foundations 12 can have many different geometrical shapes such as a cuboid, a parallelepiped or a cylinder. In the shown example, the cable foundation 12 is a cuboid. The cable foundation 12 in FIG. 3 comprises, with respect to the first end 13 (FIG. 2) of the respective stay cable 11, a front side 24 and a back side 25. The front side 24 comprises the entrance opening 22 of the through-hole 20. The back side 25 comprises the exit opening 23 of the through-hole 20. In this example, the front side 24 and the back side 25 are inclined relative to each other. In other examples, the front side 24 and the back side 25 may be parallel to each other.

(26) The stay cable 11 is passing through the through-hole 20 such that it extends with its second end 15 through the exit opening 23 from the back side 25 of the cable foundation 12. Further, the stay cable 11 is anchored at its second end 15 by using the anchoring plate 18. With respect to a direction from the first end 13 (i.e. the first anchoring point 14) to the second end 15 (i.e. the second anchoring point), the stay cable 11 is anchored at its second end 15 behind the through-hole 20.

(27) The second end 15 of the stay cable comprises a cable head 26 resting against the anchor plate 18.

(28) FIG. 4 shows a detailed view of a portion of FIG. 3 illustrating the stay cable 11 close to its second end 15. Also shown in FIG. 4 is the anchoring plate 18. The respective cable foundation 12 is not shown in FIG. 4 for clarity.

(29) Each stay cable 11 comprises several tendons 27. The tendons 27 are fixed to the cable head 26. The cable head 26 comprises a flange 28 resting against the anchoring plate 18. In particular, the flange 28 of the cable head 26 is engaging a first surface 29 of the anchoring plate 18 in a form fit.

(30) Furthermore, a second surface 30 of the anchoring plate 18 is engaging with the back side 25 of the cable foundation 12 (FIG. 3) in a form fit. In particular, a size S of the anchoring plate 18 (FIG. 3) is larger than a diameter D of the through-hole 20 of the respective cable foundation 12.

(31) FIG. 5 shows a detailed view of one of the cable foundations 112 of the tower arrangement 117 (FIG. 2) along with one of the stay cables 11 anchored to this cable foundation 112 according to a second embodiment.

(32) The cable foundation 112 according to the second embodiment is similar as the cable foundation 12 according to the first embodiment apart from a cavity 31. In the following only differences to the first embodiment will be described while a description of identical or similar features is omitted.

(33) As shown in FIG. 5, the cavity 31 of the cable foundation 112 is in communication with the through-hole 120. The cavity 31 is, in particular, in communication with the exit opening 123 of the through-hole 120. Further, the cavity 31 is arranged, with respect to the first end 13 (FIG. 2) of the respective stay cable 11, behind the through-hole 120.

(34) The cavity 31 accommodates the anchoring plate 18 and the second end 15 of the respective stay cable 11. In this manner, the anchoring plate 18 and the second end 15 of the stay cable 11 are better protected.

(35) While the cable foundation 12, 112 in FIG. 2 is arranged entirely above the ground 19, in other examples, the cable foundation 12, 112, 212 may also be arranged partly below the ground 119, as illustrated in FIG. 6. In this case, a passage way 32 through the ground 119 may be provided. The passage way 32 is, in particular arranged, with respect to the first end 13 of the stay cable 11, behind the cable foundation 212. The passage way 32 allows access to the anchoring means 18 and the second end 15 of the stay cable 11.

(36) As shown in FIG. 7, there may be a misalignment between an axis A1 of a through-hole 20 of an arranged cable foundation 12 and an axis A2 of a stay cable 11 guided through the through-hole 20. For example, an angle between the axis A1 of the through-hole 20 and the axis A2 of the stay cable 11 may have a value of up to several degrees.

(37) In order to allow for larger tolerances when erecting the tower 6, connecting the stay cables 11 with the tower 6 and arranging the cable foundations 12, 112, 212, the anchoring means 118, 218 may include means to compensate for such a misalignment between the axis A1 of the through-hole 20 and the axis A2 of the stay cable 11.

(38) FIG. 8 shows a first example for compensating for an angle deviation between the axis A1 of the through-hole 20 and the axis A2 of the stay cable 11. Shown in FIG. 8 are an anchoring plate 118 including two plate surfaces 129, 130 being inclined to each other by an angle . There may be provided several anchoring plates 118 with different angles of at least 0.5, 1, 2, 3, 4 and 5 which can be selected based on the existing misalignment (angle , FIG. 7).

(39) FIG. 9 shows a second example for compensating for an angle deviation between the axis A1 of the through-hole 20 and the axis A2 of the stay cable 11. Shown in FIG. 9 is an anchoring means 218 comprising a spherical washer 33, a mating concave nut 34 and an anchoring plate 35. The spherical washer 33 is arranged, with respect to the first end 13 (FIG. 2) of the stay cable 11, behind the anchoring plate 35. In particular, a spherical surface 36 of the spherical washer 33 faces the anchoring plate 35. Furthermore, the mating concave nut 34 is arranged between the spherical washer 33 and the anchoring plate 35 such that a concave surface 37 of the mating concave nut 34 engages with the spherical surface 36 of the spherical washer 33.

(40) In response to a misalignment of the axis A1 and the axis A2 (FIG. 7), the spherical washer 33 and the mating concave nut 34 will rotate relative to each other in a self-adjusting manner. In particular, an angle (y) between a rotational-symmetry axis A3 of the spherical washer 33 and a rotational-symmetry axis A4 of the mating concave nut 34 is adjusted.

(41) In the following, a method for erecting the wind turbine 1 of FIG. 1 is described with reference to FIG. 10.

(42) In step S1 of the method, an erected tower 6 or tower section(s) 8, 9 are provided (FIG. 1).

(43) In step S2 of the method, the stay cables 11 are connected to the tower 6 and/or the tower section 9.

(44) Step S2 may be carried out after step S1 or before step S1. For example, the stay cables 11 may be connected to the tower 6 and/or the tower section 9 prior to erecting the tower or to lifting the tower section 9. Alternatively, the stay cables 11 may also be connected to the tower 6 or tower section 9 after erecting the tower 6 or lifting the tower section 9.

(45) It is noted that step S2 may also be carried out after steps S4 and S5.

(46) In step S3 of the method, at least one cable foundation 12, 112, 212 including a through-hole 20, 120 is provided (FIGS. 3, 5).

(47) In step S4 of the method, each stay cable 11 is guided through the through-hole 20, 120 of a respective cable foundation 12, 112, 212.

(48) In the case in which step S4 is carried out after step S2, i.e. in which the stay cables 11 are already anchored at the tower 6, the stay cables 11 are guided through the through-hole 20, 120 without having the cable head 26 (FIG. 4). For example, the individual tendons 27 of each stay cable 11 are guided together or one-by-one through the through-hole 20, 120.

(49) In step S5 of the method, each stay cable 11 is anchored at its second end 15 behind (with respect to its first end 13) the respective through-hole 20, 120 using the anchoring means 18, 118, 218.

(50) In particular, the stay cables 11 are guided through a through-hole 38 of the anchoring plate 18, 118, 218 (FIG. 4). After guiding the stay cables 11 through the through-holes 20, 120 of the cable foundations 12, 112, 212 and the through-holes 38 of the anchor plates 18, 118, 218, the cable head 26 is connected to each stay cable 11 (FIG. 4).

(51) In the case in which step S2 (anchoring the stay cables 11 at the tower 6 or tower section 9) is carried out after steps S4 and S5 (anchoring the stay cables 11 at the cable foundations 12, 112, 212), the cable head 26 may be attached to each stay cable 11 before guiding the stay cables 11 through the through-hole 38 of the anchoring plate 18, 118, 218 and through the through-hole 20, 120 of the cable foundations 12, 112, 212.

(52) In step S6 of the method, a potential misalignment between the axis A1 of the through-hole 20, 120 and the axis A2 of a respective stay cable 11 (FIG. 7) may be compensated. Step S6 is optional. Step S6 may be carried out simultaneously with step S5.

(53) Such a compensation is, for example, carried out by selecting an anchoring plate 18, 118 from a group comprising an anchoring plate 18 whose two plate surfaces 29, 30 are parallel to each other and anchoring plates 118 whose two plate surfaces 129, 130 are inclined to each other by an angle of at least 0.5, 1, 2, 3, 4 and 5 (FIG. 8).

(54) Alternatively, the anchoring means 218 comprise, for example, a spherical washer 33, a mating concave nut 34 and an anchoring plate 35 (FIG. 9). The spherical washer 33 and the mating concave nut 34 will rotate relative to each other in a self-adjusting manner in case of a misalignment between the axis A1 of the through-hole 20, 120 and the axis A2 of a respective stay cable 11.

(55) In step S7 of the method, the stay cables 11 are tensioned between its first end 13 anchored at the first anchoring point 14 at the tower 6 or tower section 9 and its second end 15 anchored at the second anchoring point 16 at the respective anchoring means 18, 118, 218.

(56) Tensioning means may be arranged either at the first anchoring point 14 at the tower 6 or tower section 9 or at the second anchoring point 16 at the respective anchoring means 18, 118, 218. Step S7 may be carried out during or directly after step S2 or step S5.

(57) Although the present invention has been described in accordance with preferred embodiments, it is obvious for the person skilled in the art that modifications are possible in all embodiments.

(58) 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.

(59) 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.