WO2015157835A1

WO2015157835A1 - Tower for generating wind power

Info

Publication number: WO2015157835A1
Application number: PCT/BR2015/000055
Authority: WO
Inventors: Afonso Henrique MASCARENHAS DE ARAÚJO; Émerson Camilo DA COSTA; Paulo Henrique CARDOSO DE MELO; Wanderson MENDES ALVES; Iara Maia SOUTTO MAYOR
Original assignee: Vallourec Tubos Do Brasil S.A.; Cemig Geração E Transmissão S.A.; Sá Carvalho S.A.; Rosal Energia S.A.
Priority date: 2014-04-15
Filing date: 2015-04-15
Publication date: 2015-10-22
Also published as: BR102014009219A2; BR102014009219A8

Abstract

The present invention relates to a tower (1) for generating wind power, comprising at least three columns (3) extending from a base of the tower up to the upper end thereof, each column (3) comprising a plurality of interconnected tubular elements and a plurality of tubular elements mounted in the form of a trellis (4) between the columns (3) thereby forming the structure from the base to the upper end of the tower (1).

Description

Report of the Invention Patent for "WIND POWER GENERATOR TOWER".

The present invention relates to lattice towers using tubular steel profiles for wind turbine installation and wind power generation, with the aim of having a new tower option that will also enable its transportation and assembly in hard to reach areas.

DESCRIPTION OF TECHNICAL STATE

Currently, there is a major societal concern with environmental preservation and investment in clean energy sources. Wind energy is proving to be a very efficient source of clean energy and, as a result, attracting investment. However, it faces some barriers that discourage its implementation. Commonly used wind power towers are extremely large and are made from very large and extremely heavy parts. Wind farms are generally installed in large windy locations and should preferably have access to large roads that allow parts to be transported and assembled on site using large, heavy equipment such as large cranes. postage.

These factors limit the feasibility of installing wind turbines in high wind locations, where wind power is quite high, such as mountainous locations, but which are accessible only by secondary roads and with limited flat spaces for installation. Sometimes it may be necessary to expropriate some regions and widen the roads to allow the transportation of parts and equipment. These procedures, in addition to being inconvenient for the local community, also increase the costs related to the towers implementation.

Some designs of wind turbine towers produced from metal profiles, such as sheet metal and L-profiles, on which a tubular-shaped end of the tower are mounted, and the naceie are connected to the tower by a prior art, are known in the art. metal connection, in which the wind turbine blades are fixed. However, these projects also face a number of technical problems, as the towers are often quite high, and installed in high and frequent wind locations. For these reasons, the towers are subjected to high stresses and are also subject to atmospheric corrosion. Thus, metal profile towers need to be made up of parts with high mechanical strength and good corrosion resistance. Such features are also required by their connections.

The present invention therefore aims at the development of lattice towers using seamless or seamless metal tubular steel profiles for wind turbine installation which enables the transportation and erection of raised towers in any areas, including difficult to reach, such as mountainous areas, minimizing the use of special transports and without requiring significant changes to the infrastructure of the site, thus reducing the deployment costs of wind farms.

It is also an object of the present invention to provide towers with high mechanical strength and also high corrosion performance that can withstand the harsh conditions of the installation sites, and may even minimize the need for corrosion protection of the towers.

SUMMARY OF THE INVENTION

The objects of the invention are achieved by a tower for wind power generation, comprising at least three columns extending from a tower base to its upper end, each column consisting of a plurality of connected metal tubular elements; and a plurality of lattice-mounted metal tubular members interconnecting the columns, forming the base structure to the upper end of the tower.

The tower may further comprise rigid frames attached, interconnecting the columns.

Said tubular members may be comprised of joined pipe compositions, each pipe composition comprising at least two pipes joined together by metal connecting elements which are selected from the group comprising welds, plates metal pipes, metal pipes, metal beams, "U", "Ί" and "H" profiles, angles and their compositions The connecting elements are fixedly trussed between the pipes of the pipe composition.

The tubular members of the lattice structure are preferably joined together by fasteners connected to the ends of the tubular members, such fasteners being at least one of welds, connection plates, flanges, "T" "U", Ί "and "H", angles, metal tubes and their compositions Fixing elements are fixed to the tubular elements by welding, screwing or riveting Fixing between the fixing elements is by welding, screwing or riveting.

The tower preferably has a cross-section with N-sided equilateral polygon geometry, with N ranging from 3 to 12, having at each vertex a column.

At least some of the tubular elements may be filled with concrete, reinforced concrete, or fiber concrete.

The tower may have a lower segment whose columns form a first inclination angle with a horizontal plane,

an upper segment whose columns form a second inclination angle with the horizontal plane, and a transition segment between the lower segment and the upper segment whose columns form a transition angle with the horizontal plane.

Alternatively, the tower has clips connecting the structure to a foundation.

BRIEF DESCRIPTION OF THE FIGURES

Other features and advantages of the wind power tower and the process for assembling it according to the invention will be apparent from reading the description herein and non-limiting examples with reference to the accompanying drawings, in which:

Figure 1 shows an embodiment of the tower for wind power generation according to the invention;

Figure 1A shows a side view of a tower for wind power generation during its crane mounting process (tower crane);

Figure 1B shows a side view of the wind power tower of Figure 1A following its crane (tower crane) assembly process;

Figure 2A shows a top view of a lattice tower according to the invention with a triangular base;

Figure 2B shows a top view of a lattice tower according to the invention with a square base;

Figure 2C shows a top view of a lattice tower according to the invention with an octagonal base;

Figure 2D shows a top view of a lattice tower according to the invention with a hexagonal base;

Figure 3A shows a cross-sectional view of a first embodiment of a two-tube circular section pipe composition used in the tower structure according to the invention;

Figure 3B shows a cross-sectional view of a first embodiment of a three-tube circular section pipe composition used in the tower structure according to the invention;

Figure 3C shows a cross-sectional view of a first embodiment of a two-tube rectangular section pipe composition used in the tower structure according to the invention;

Figure 3D shows a cross-sectional view of a first embodiment of a rectangular three-tube pipe composition used in the tower structure according to the invention;

Figure 4A shows a front view of pipe compositions and their respective connecting elements;

Figure 4B shows a front view of pipe compositions with their respective connecting elements and connecting elements with other tube compositions or tower structure elements according to the invention;

Figure 5 shows six embodiments of the tower according to the invention using different lattice shapes and their combinations in the upper and lower portions.

Figure 6 shows an embodiment of flange-shaped fastener between tubular members applicable to pipes of circular or rectangular section;

Figure 7A shows a front view of another embodiment of tubular member connection using a "T" profile applicable to circular or rectangular section tubing;

Figure 7B shows a side view of the connection shown in Figure

7A;

Figure 8 shows a cross-sectional view of the attachment of a tower column to the ground;

Figure 9A shows a top view of figure 17 according to one embodiment of the invention using rectangular profile tubular member and rectangular plate;

Figure 9B shows a top view of figure 17 according to one embodiment of the invention using circular profile tubular member and rectangular plate;

Figure 9C shows a top view of figure 17 according to one embodiment of the invention using circular profile tubular member and circular plate;

Figure 10 shows a sequence of tower assembly steps according to the present invention using crane (tower crane) or other mounting equipment;

Figure 11A shows a top view of a triangular base tower during the assembly process according to the present invention, showing the distance between the tower's center of gravity and the cranes (tower crane);

Figure 11B shows a top view of a square base tower during the assembly process according to the present invention, showing the distance between the tower's center of gravity and the cranes (tower crane);

Figure 12 shows an embodiment of the tower for wind power generation according to the invention constituted as cable-stayed tower;

Figure 13 shows an embodiment of the tower for wind power generation according to the invention consisting of two approximately cylindrical segments; and

Figure 14 shows a wind energy generation tower embodiment according to the invention having a transition segment between the upper and lower segments.

DETAILED DESCRIPTION OF THE INVENTION

As can be seen from figures 1, 1A and 1B, the wind power tower 1 according to the present invention has at least three columns 3 extending from the tower base to its upper end. Each of these columns is made up of several tubular elements connected to each other successively to a desired height, there being at certain height intervals flat locking structures 5 at some levels, as shown in Figure 1.

The structure of the tower 1 is complemented by a plurality of diagonal tubular elements and mullions which are lattice connected 4, interconnecting the columns 3, forming a lattice of base bars to the top end of the tower. These tubular elements have sufficient strength to withstand the stresses to which the tower is subjected. The columns 3 of tower 1 may also be interconnected by rigid frames (not shown) in addition to the truss structures 4. The tubular elements used to form the tower structure have a circular or rectangular cross section, or any type of cross section, and are hot-rolled seamless tubes or seamed tubes made from welded sheets. However, hot-rolled seamless tubes are classified by international standards into higher buckling curves, such as the EN 1993-1 standard "a" or " ₀ " bends, which are therefore better performing, and for this reason are prefer to generate lighter structures, with greater ease of assembly and, consequently, more economical

The tubes are preferably comprised of unbound carbon steels and / or low alloy or microalloyed steels. The steels can be slippable, which guarantees high corrosion performance and can even minimize the need for towers corrosion protection. In addition, pipes filled with concrete, reinforced concrete, or even concrete with steel fibers or any other material may be used in the tower structure. These concrete-filled tubes may alternatively be used only in some regions of the tower structure where there is the greatest effort and may be combined with unfilled tubes.

The tower base and tower cross-section have an N-sided equilateral polygon geometry such that N preferably ranges from 3 to 12, having at each vertex a column 3 consisting of tubular elements or tube compositions. The number N of columns 3 will therefore be equal to the number N of sides. The number of sides of the polygon and the number of columns 3 may also vary depending on the needs of the project. In the embodiment of the invention shown in Figure 2A, for example, the tower is constructed using three columns 3, so that its base has a triangular geometry. The triangular base tower has the advantage of minimizing assembly costs due to the reduction in cargo handling distance 6 (nacelle, blades and other wind turbine parts) by the mounting equipment (Figure 11A) when compared to the tower square base (figure 1 B). In this case, such equipment will have shorter cargo handling distances, which will enable the use of lighter equipment and consequently lower cost.

Alternatively, the tower cross section can also be quadrangular having 4 columns (as in figure 2B), or pentagonal having 5 columns, or hexagonal having 6 columns (as figure 2D), or heptagonal having 7 columns or even octagonal with 8 columns (as per Figure 2C), and so on, depending on the area of application, loads to be applied to the structure, tower height, among other factors, including aesthetic aspects.

The tubular elements used in the constitution of the columns 3 and the lattice structure 4 between the columns may be individual tubes joined together, or even compositions of tubes joined together, if it is necessary to provide greater resistance to the tower, for example in very tall towers with high loads. Examples of pipe compositions 7 are shown in Figures 3A to 3D in cross section and Figures 4A and 4B in front view.

Each tube composition 7 ^' consists of two, three or more tubes 8 joined together by metal connection elements 9 at their ends and / or along their lengths, or are directly welded, thus forming a single element to each other. be used in tower assembly. Figures 3A and 3C illustrate the case of compositions 7 of two circular or rectangular section tubes 8 joined together, and Figures 3B and 3D illustrate examples of compositions 7 of three pipe 8 of circular or rectangular section joined together.

As connecting elements 9 between the pipes of the column pipe compositions, preferably welds, metal pipes, sheet metal, "U", "1" and "H" profiles, angles and their compositions, or any other type of pipe may be used. metal profile with another cross-sectional shape. Such connecting elements 9 may be intermittently or continuously present between the tubes 8 of the compositions 9 along the length thereof.

In the left example of Figures 4A and 4B, the tubes 8 of composition 7 are joined together along their length by a sheet metal 9 whose longitudinal ends are welded to the pipes.

In the examples shown in the center and right of Figures 4A and 4B, when the connecting elements 9 used are pipes or other types of metal profiles, the pipes 8 of composition 9 may be joined together by securing the connecting elements of lattice, or by fixing these elements parallel to each other, and perpendicular to the tubes 8, in a connection commonly called locking. These connecting elements 9 are generally fixed to the pipes by direct welding between the pieces.

The tubular elements constituting the lattice structure (diagonal and upstream) mounted between the tower columns can be fixed to each other in different ways by welding or fastening elements 10, such as connecting plates, flanges, T-profiles. "," U ", T and Ή", angles, tubes and their compositions which are joined to the tubular elements by welding or bolting. Some examples of fastening elements 10 are shown in Figures 6, 7A and 7B. Figure 6 shows examples of circular section flanges 10 used with circular section pipes 8, and rectangular section flanges 10 used with rectangular section pipes 8. These flanges are attached to the ends of the tubular members and are provided with holes that allow tubular members bolts to each other or to other structural elements of tower 1, and even to the column Figures 7A and 7B show a front view and a side view of a fastener 10 in the form of a T-profile also welded to the end of the tubular member 8, and whose longer tab of the T extends axially from the tube. This longer flap may be provided with bolt-on holes with other frame components or fasteners.

Preferably, connections will be employed to facilitate and speed up the assembly process, seeking solutions that guarantee good performance during the service life of the structure. For this reason, bolted connections with flanged or end plate plates, "T" or "perfis" profiles described above are preferably employed, always paying particular attention to the effects of fatigue to which these connections may be subjected. , which does not prevent the use of connections welded between the connecting elements, when deemed most suitable for the project.

The lattice connection between the tubular elements 8 of the structure can be made in different lattice shapes. Examples of types of connections between tubular elements used in the structure of the present invention are type DK, K, KK, KT, N / T, TT, DT, X, XX, Y, and DY connections, other forms of connection being excluded. and combinations thereof within the same tower structure.

Figure 8 shows in cross section a possible way of fixing the tower 1 to the ground, not excluding other shapes. The tubular element constituting the column has a base plate 11 attached to its lower end, as shown in Figures 9A, 9B and 9C. In the case of tubes with rectangular or circular section, plate 11 of rectangular section can be used (Figures 9A, 9B). Optionally, for circular section pipes, plate 11 with circular section may be employed (Figure 9C). The tubular elements are usually welded to the base plates 11, and these plates are provided with perforations that allow the fitting of threaded bars (anchor bolts).

In addition, tower 1 can be constructed from several modules 12 which can be individually pre-assembled and then assembled and fixed on top of each other as shown in Figure 10.

Figure 5 shows several examples of towers 101, 102, 103, 104, 105 and 106 having an upper segment 13 and a lower segment 14 with different geometries. As can be seen from towers 101, 102 and 103, the tower can be constructed such that in the upper segment 13 the tubular elements are joined by one type of truss and in the lower segment 14 the tubular elements are joined by another type. lattice. This variation of lattice modalities can also occur in one tower segment. In towers 104, 105 and 106, the same type of truss is used from the base to the top of the tower. Still in this sense, the towers of the present invention may also be formed such that the base of the upper segment 13 has a type of square, triangular, geometry. among others, and the base of the lower segment 14 has a different type of geometry than the upper one. Thus, an example design of such a tower could have a module 12 or lower segment 14 with a square base, and a module 12 or upper segment 13 with an octagonal base. The shape of the tower bases and the type of truss employed are determined for each project, and may vary depending on the structural strength that the tower must present, its height, climatic and geographical conditions of the installation site, costs, among others.

In Figure 12, a version of the windmill tower 107 is shown, which has snaps 17 at the bottom connecting the tower frame 107 to the foundation. This cable-stayed tower 107 may also be designed with the same cross-section along all or nearly all of its length.

Tower 1 can be designed with different column inclinations in different vertical segments to adjust their natural frequency to the limits required by the equipment, thus avoiding interference with wind turbine (wind power generation equipment) operation.

In the example shown in figure 14, the tower can be made up of three segments with different column inclinations:

a lower segment 14 whose columns 3 form a first inclination angle 141 with the horizontal plane,

- an upper segment 13 whose columns 3 form a second inclination angle 131 with the horizontal plane, and

a transition segment 15 between the lower segment 14 and the upper segment 13, forming a transition angle 151 with the horizontal plane.

In this example, the angle 151 formed by column 3 with the horizontal plane in the transition segment 15 is smaller than the corresponding angle in the lower segment 14 and the upper segment 13. However, these angles can be adjusted according to the needs of the project. .

The example shown in figure 13 is an extreme case of the tower. shown in Figure 14, where the angle of the columns 3 with the horizontal plane is right (90 °) at the lower end 14 and upper end 13. Consequently, the angle with the horizontal plane of the transition segment is of 0 ^o. In this case, the lower segment 14 has a larger diameter than the upper segment 13. Thus, the transition segment 15 has horizontal beams interconnecting the lower segment 14 and the upper segment 13.

In other embodiments, the angles 131, 141, 151 of columns 3 of all segments 13, 14, 15 may be the same.

Tower 1 can be assembled in various ways. For example, initially at least one tubular member of each of the tower columns 3 is fixed to the ground. Several tubular elements can be initially fixed together that make up each column. Thereafter, the tubular elements constituting the truss 4 and / or the gantry are fixed between the columns 3.

The diagonal tubular elements and mullions that form part of the lattice structure 4 can be connected to each other on site during the tower assembly. Another option is for the lattice structure 4 to be divided into modules, which can be pre-assembled on site, and then each module is mounted on the next lower module.

In situations where transport is not the bottleneck of the tower assembly process, the smaller tubular elements may be properly connected in the frame factories, thus forming larger modules 12 such as lattice segments and / or the compositions. 7 of tubular elements 8 used in this structure. Such larger pieces should thus be transported from the place of manufacture to the tower deployment site, where they will be mounted on the tower structure 1 using the same equipment and with less man-hour consumption in the field.

This step of connecting the tubular elements to larger parts can be done even before the tower assembly process and the columns are grounded.

When the tower consists of several 12 modules assembled together, the process is carried out with separate tower module assembly steps followed by tower module 12 mounting steps on top of one another. These tower modules 12 are comprised of column segments and diagonal tubular elements and truss-mounted mullions or elements docked between the columns as shown in Figure 10.

These steps can be performed with the aid of 2 cranes or wheeled or crawler cranes. These diverse facilities and possibilities for composing the structural parts and assembling the towers 1 may minimize the need to use heavier equipment in the wind farm deployment process, and this equipment can be used, when necessary, only in the wind turbines assembly phase. .

Another option of the assembly process is to use auxiliary assembly equipment, to be installed on the top of the tower, able to lift and assemble the parts that make up the wind turbine and its blades.

Having described examples of preferred embodiments, it should be understood that the scope of the present invention encompasses other possible variations, being limited only by the content of the claims only, including the possible equivalents thereof.

Claims

1. Tower (1) for wind power generation, characterized by the fact that it comprises:

at least three columns (3) extending from a tower base to its upper end, each column (3) being comprised of a plurality of connected metal tubular members; and

a plurality of lattice-mounted metal tubular elements (4) interconnecting the columns (4), constituting the base structure to the upper end of the tower.

Wind energy generation tower according to claim 1, characterized in that it further comprises rigid frames attached, interconnecting the columns (3).

Wind energy generation tower according to one of Claims 1 to 2, characterized in that the tubular elements are composed of pipe compositions (7) joined together, each pipe composition (7) comprising at least at least two pipes (8) joined together by metal connection elements (9).

Wind power tower according to claim 3, characterized in that the connecting elements (9) are selected from the group comprising welds, sheet metal, metal tubes, metal beams, "U" profiles, T and Ή ", angles and their compositions.

Wind power tower according to Claim 3 or 4, characterized in that the connecting elements (9) are fixedly interlocked between the tubes (8) of the tube composition (7).

Wind energy generating tower according to one of Claims 1 to 5, characterized in that the tubular elements of the lattice structure (4) are joined together by fastening elements (10) connected to the ends of the tubular elements; these fasteners (10) being at least one of welds, connecting plates, flanges, "T""U", Ί "and" H "profiles, angles, metal pipes and their compositions.

Wind power tower according to Claim 6, characterized in that the fastening elements (10) are fixed to the tubular elements by welding, screwing or riveting.

Wind power tower according to one of Claims 6 to 7, characterized in that the fixing between the fixing elements (10) is by welding, screwing or riveting.

Wind power tower according to one of Claims 1 to 8, characterized in that it has a cross-section with equilateral polygon geometry with N sides, where N varies from 3 to 12, having at each vertex , a column (3).

Wind power tower according to one of Claims 1 to 9, characterized in that at least some of the tubular elements are filled with concrete, reinforced concrete or fiber-reinforced concrete.

Wind power tower according to one of Claims 1 to 10, characterized in that it has:

a lower segment (14) whose columns (3) form a first inclination angle (141) with a horizontal plane,

an upper segment (13) whose columns (3) form a second inclination angle (131) with the horizontal plane, and

a transition segment (15) between the lower segment (14) and the upper segment (13), whose columns (3) form a transition angle (15) with the horizontal plane.

Wind energy generation tower according to one of Claims 1 to 11, characterized in that it has stacks (17) connecting the structure to a foundation.