TOWER SEGMENT, TOWER SECTION, TOWER, WIND TURBINE, AND METHOD FOR PRODUCING A TOWER SEGMENT AND FOR CONNECTING TOWER SEGMENTS

20190170122 · 2019-06-06

    Inventors

    Cpc classification

    International classification

    Abstract

    A tower segment of a tower of a wind turbine, a tower portion of a wind turbine, a tower of a wind turbine, a wind turbine, a method of producing a tower segment of a wind turbine and a method of connecting tower segments of a wind turbine. The tower segment includes a compression element and a tension element, wherein the tension element is arranged with its main direction of extent substantially horizontally in the installation state and is spaced from the tower segment in a direction in orthogonal relationship with its main direction of extent and is connected to the compression element by way of an intermediate element.

    Claims

    1. A tower segment of a tower of a wind turbine, the tower segment comprising: a compression element; and a tension element coupled to the compression element by an intermediate element, wherein the tension element has a longitudinal length arranged substantially horizontally in an installation state and is spaced from a surface of the tower segment in a direction that is orthogonal to the longitudinal length.

    2. The tower segment according to claim 1 wherein the tension element has a clamping element.

    3. The tower segment according to claim 1 wherein the intermediate element is of a pivotable configuration.

    4. The tower segment according to claim 1 wherein the compression element has at least one lateral surface arranged and adapted in the installation state to abut a lateral surface of an adjacent tower segment.

    5. The tower segment according to claim 1 wherein the compression element has two lateral surfaces that are inclined relative to each other.

    6. The tower segment according to claim 1 wherein the intermediate element is connected to the compression element, the tension element, or both by a plurality of connecting elements.

    7. The tower segment according to claim 1 wherein the compression element has a positioning element at a connecting surface that is an upper surface or a lower surface in the installation state.

    8. The tower segment according to claim 1, wherein the tension element is coupled to the compression element by two intermediate elements, wherein a spacing between the two intermediate elements in the longitudinal length of the tension element is a multiple of a spacing between a respective one of the two intermediate elements and a closest lateral surface of the compression element.

    9. The tower segment according to claim 1 wherein the spacing between the tension element and the compression element is at a maximum 50% of a radius of a tower.

    10. A tower portion of a wind turbine comprising a plurality of tower segments according to claim 1, wherein the tension elements of adjacent tower segments are connected together, and the compression elements of adjacent tower segments abut one another.

    11. The tower portion according to claim 10 wherein upper connecting surfaces of the compression elements are in different planes than lower connecting surfaces of the compression elements.

    12. A tower of a wind turbine comprising at least one tower portion according to claim 10.

    13. A wind turbine comprising the tower according to claim 12.

    14. A method of producing a tower segment of a wind turbine the method comprising: providing a compression element; providing a tension element; and connecting the tension element to the compression element using an intermediate element, wherein the tension element has a longitudinal length that extends substantially horizontally in an installation state and is spaced from the tower segment in a direction that is orthogonal to the longitudinal length.

    15. A method of connecting tower segments of a wind turbine, including: providing two tower segments according to claim 1; abutting the compression elements of the two tower segments; and connecting the tension elements of the two tower segments.

    16. The tower segment according to claim 3, wherein the intermediate element is pivotably connected to the compression element, the tension element or both.

    17. The tower segment according to claim 6, wherein the plurality of connecting elements are maintenance-free.

    18. The tower segment according to claim 7, the compression element has a plurality of positioning elements.

    19. The tower segment according to claim 9, wherein the spacing between the tension element and the compression element is at a maximum 25% of a radius of a tower.

    Description

    BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

    [0058] Preferred embodiments of the invention are described by way of example with reference to the accompanying drawings in which:

    [0059] FIG. 1 shows a three-dimensional view of a wind turbine having a tower and a pod,

    [0060] FIG. 2 shows a three-dimensional view of a tower for a wind turbine of polygonal cross-section,

    [0061] FIG. 3 shows a horizontal section through the tower of FIG. 2,

    [0062] FIG. 4 shows an enlarged view of a 90 cut-out portion of FIG. 3,

    [0063] FIG. 5 shows an enlarged view of a corner as shown in FIG. 4 with the flow of forces illustrated therein,

    [0064] FIG. 6 shows a three-dimensional view of a tower portion with a first plane of tower segments,

    [0065] FIG. 7 shows a tower portion as shown in FIG. 6 with two first tension element rings,

    [0066] FIG. 8 shows the tower portion of FIG. 7 with a second plane of tower segments,

    [0067] FIG. 9 shows the tower portion of FIG. 8 with two second tension element rings,

    [0068] FIG. 10 shows a plan view of a tower in the assembly state with a first and a second plane of tower segments and a third plane of tower segments, which is not yet fitted in place, and

    [0069] FIG. 11 shows the tower of FIG. 10 with the third plane of tower segments fitted in place.

    DETAILED DESCRIPTION

    [0070] FIG. 1 shows a wind turbine 100 comprising a tower 102 and a pod 104. A rotor 106 having three rotor blades 108 and a spinner 110 is arranged at the pod 104. In operation the rotor 106 is caused to rotate by the wind and thereby drives a generator in the pod 104. The tower 102 shown in FIG. 1 is of a cross-section in the form of a circular ring. The tower 102 can have tower segments according to the invention, wherein the tower segments shown here in the further Figures for a tower of polygonal cross-section would have to be appropriately modified from a flat configuration of the compression elements to a curved configuration.

    [0071] FIG. 2 shows a tower 20 for a wind turbine, wherein the tower 20 has a vertical longitudinal axis and a polygonal cross-section in orthogonal relationship with that longitudinal axis. The tower 20 includes a multiplicity of tower segments 200, the surface extent of which is flat, without curvature or radius, thus affording a polygonal tower shape which here is octagonal. A typical height for a tower of a wind turbine is for example 150 mm. The tower can be made up substantially completely from tower segments as described herein. However it is also possible for only a part, preferably a lower part of the tower, for example up to a height of 75 m, to be constructed from tower segments as described herein, and for a further, preferably upper, part of the tower to be for example in the form of a steel tower.

    [0072] FIG. 3 shows a horizontal section through the tower of FIG. 2. FIG. 4 shows an enlarged portion of the 90 cut-out portion identified by W in FIG. 3. FIG. 5 in turn shows a corner as illustrated in FIG. 4 on a still further enlarged scale, with the flow of forces illustrated therein, wherein D denotes the double-headed arrow for compression forces and Zt, Zr denote the double-headed arrows for tensile forces in tangential and radial directions.

    [0073] As can be seen in particular from FIGS. 3 to 5 two kinds of tower segments are used. On the one hand tower segments 210 with a compression element 250 and a tension element 310 and on the other hand tower segments 220 which, besides the compression element 250, have a tension element 320 with a tightening or clamping element 330. The clamping element 330 is in the form of a turnbuckle with a plurality of clamping screws 331 so that the tension element ring 300 can be acted upon with a clamping force and thus prestressed, by tightening the clamping screws 331.

    [0074] The compression elements 250 are spaced from the tension elements 310, 320 in the radial direction relative to the longitudinal axis of the tower and thus here also substantially in a horizontal direction. In this example the spacing between the compression elements 250 and the tension elements 310, 320 approximately corresponds to the thickness of the compression elements 250 in a direction in orthogonal relationship with their flat surface extent. The tension elements 310, 320 are arranged on the insides of the compression elements 250 and thus are disposed in the interior of the tower in the installation state and in the operational state of the wind turbine.

    [0075] The tension elements 310, 320 are pivotably connected to the compression elements 250 by way of intermediate elements 410. The intermediate elements 410 have a first intermediate portion 411 connected to the compression element 250 by way of headed bolt dowels 421. Preferably the first ends of the first intermediate portions 411 are concreted into the compression elements 250 with the headed bolt dowels 421. Pivotably connected to the first intermediate portion 411 is a second intermediate portion 412 which in turn is pivotably connected to an end of the tension elements 310, 320. The tension elements 310, 320 of adjacent tower segments 210, 220 are pivotably connected together by way of tensile connectors 430. The pivotable connections which in particular permit pivotability of the elements connected together by way thereof about a substantially vertical axis are embodied by connecting elements 422, preferably in the form of nuts with cotter pins. In particular a configuration of the connections between the tensile elements 310, 320, the intermediate elements 410 and the compression elements 250 in maintenance-free and fail-safe form is preferred.

    [0076] Each of the tower segments 210, 220 has two intermediate elements 410, the mutual spacing of which in the main direction of extent of the respective tension elements 310, 320 is a multiple of the spacing thereof relative to the lateral surfaces 251 of the compression elements 250. The lateral surfaces 251 of adjacent tower segments 210, 220 form a butt connection. The two lateral surfaces 251 of each compression element 250 are oriented in vertical planes and also oriented in the radial direction. The two lateral surfaces 251 of each compression element 210, 220 are thus inclined relative to each other.

    [0077] As can be seen in particular in FIG. 5 the tension elements 310, 320 and the connecting elements 410 are substantially acted upon by tensile forces Zt, Zr. In contrast the compression elements 250 are substantially acted upon by compressive forces D. The tensile prestressing applied by the clamping elements 330 to the tensile elements 320 and from there to the entire tensile element ring 300 causes a corresponding prestressing in the compression elements 250. By virtue of the spacing of the tension elements 310, 320 from the compression elements 250 and the lever effect resulting therefrom it can be provided that the compressive prestressing D in the compression elements 250 is greater and thus leads to a secure butt connection by way of frictional connection at the respectively adjacent lateral surfaces 251, than the tensile prestressing Zt in the tension elements 310, 320. In addition the substantially radially acting tensile force Zr in the connecting elements 410 can also be reduced, preferably to a value less than the tensile prestressing Zt in the tension elements 310, 320, in particular to a value less than half the tensile prestressing Zt in the tension elements 310, 320.

    [0078] Arranged in the intermediate space between the compression elements 250 and the tension elements 310, 320 are vertically extending stressing cables 500 which prestress the tower in a vertical direction.

    [0079] Preferably the number of clamping elements 330 in a tension element ring 300 is as low as possible, for example there may be only one clamping element 330. That facilitates assembly and in particular results in a shorter amount of time being required for assembly, for example if the clamping elements are tightened by hand. It is also possible to use preferably electric hand tools for tightening the clamping elements, for example impact wrenches or torque wrenches.

    [0080] FIGS. 6 to 9 diagrammatically show assembly of tower portions 21, 22. FIG. 6 firstly shows a tower portion 21 with tower segments 201 in a first plane. As can be seen the upper connecting surfaces 252 of the tower segments 201 are disposed in different planes. FIG. 7 shows the tower portion 21 with two tension element rings 301 indicated by broken circles.

    [0081] After the tower segments 201 in the first plane have been prestressed in that way, as shown in FIG. 8 the tower segments 202 in the second plane, that is to say a second tower portion 22, can be arranged on the upper connecting surfaces of the tower segments 201 in the first plane, that is to say the first tower portion 21. The upper and lower connecting surfaces of the tower segments 202 in the second plane are also disposed in different planes. As indicated in FIG. 9 by the dash-dotted circles the tower segments 202 in the second plane, that is to say the second tower portion 22, are also prestressed with tension element rings 302. In that way a multiplicity of tower portions can be arranged in mutually superposed relationship up to a desired tower height.

    [0082] The tension element rings 301, 302 can be of a polygonal configuration or in the form of a circular ring.

    [0083] FIG. 10 shows a plan view of a tower in the assembly state with a first and a second plane of tower segments 201, 202 and a third plane of tower segments 203, that has not yet been fitted in place. In FIG. 11 the third plane of tower segments 203 has then been fitted in place.

    [0084] FIG. 10 does not show the tension elements of the tower segments 201 in the first plane. The tower segments 202 in the second plane have tension elements 320 with clamping elements 330. The tower segments 203 in the first plane have tension elements 310 without clamping elements. Preferably the tension elements 310, 320 are already fixed to the compression elements 250 of the tower segments 202, 20 before the assembly operation, as can be seen in FIG. 10 in particular at the tower segments 203 which have not yet been fitted in position.

    [0085] By virtue of the mutually inclined lateral surfaces 251 of the tower segments 201, 202 and 203, upon assembly the tower segments 201, 202, 203 can be introduced in an insertion direction E into an intermediate space between two adjacent tower segments. FIG. 11 shows the tower segments 203 which are then in the assembled state, in which the tower segments 203 are fitted into the intermediate spaces between adjacent tower segments in the second plane 202 and the ring of tension elements 300 is closed.

    [0086] The tower segments described here have inter alia the advantage that they permit a substantially deformation-free and force-locking connection in respect of the compression elements, and also keep the radial tensile forces low. In particular the pivotable connection permits more uniform prestressing in the elements of a tower portion so that one clamping element per tower portion may already be sufficient.