Transition section for wind turbine tower testing

Abstract

The present invention discloses a transition section for a wind turbine tower test, the transition section comprising a lower flange for connecting to a tower foundation of a test wind farm, an upper flange for connecting to a bottom flange of a tower to be tested, and a connecting side wall between the upper flange and the lower flange, the lower end of the connecting side wall being connected to the inner side of the lower flange, the upper end of the connecting side wall being connected to the outer side of the upper flange, the outer profile of the connecting side wall being configured as an arc structure that tapers from bottom to top and bulges outward, the wall thickness of the connecting side wall being greater than the thickness of the upper flange and the lower flange, and the upper flange, the lower flange and the connecting side wall being integrally formed. The transition section of the present invention can solve the problem of adapting unit towers of different sizes in a specific test wind farm and has a strong load-bearing capacity.

Description

Technical Field

[0001] The invention relates to the technical field of wind power generation, and in particular to a transition section used for a tower test of a wind turbine generator set. Background Art

[0002] With the rise of high-power wind turbines, the tower height is getting higher and higher. With the increase of wind turbine impellers and capacity, the bottom diameter of the tower is also getting larger, reaching 5 meters or even larger. However, the test wind farm cannot set up a foundation for each experimental unit. Generally, a larger foundation is made. Usually, the diameter of the foundation anchor plate flange is usually about 7 meters, so as to meet as many units as possible. In this case, a transition section needs to be set between the foundation and the tower to realize the installation of the tower to be tested. The transition section needs to make a trade-off between the overall configuration, weight and economy, and obtain the most cost-effective structural form on the basis of meeting the load-bearing requirements. Summary of the invention

[0003] A series of simplified concepts are introduced in the Summary of the Invention, which will be further described in detail in the Detailed Description of the Invention. The Summary of the Invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0004] In order to at least partially solve the above-mentioned problems, the present invention provides a transition section for a wind turbine tower test, wherein the transition section comprises a lower flange for connecting to a tower foundation of a test wind farm, an upper flange for connecting to a bottom flange of a tower to be tested, and a connecting side wall between the upper flange and the lower flange, wherein the lower end of the connecting side wall is connected to the inner side of the lower flange, the upper end of the connecting side wall is connected to the outer side of the upper flange, the outer contour of the connecting side wall is configured as an arc structure that gradually contracts from bottom to top and bulges outward, the wall thickness of the connecting side wall is greater than the thickness of the upper flange and the lower flange, and the upper flange, the lower flange and the connecting side wall are integrally formed.

[0005] Furthermore, the outer wall surface and the inner wall surface of the connecting side wall are both arc surface structures convex outward.

[0006] Furthermore, the wall thickness of the connecting side wall gradually decreases from bottom to top.

[0007] Furthermore, the ratio of the wall thickness of the lower end portion of the connecting side wall to the wall thickness of the upper end portion is between 1.2-1.5, and the ratio of the wall thickness of the upper end portion of the connecting side wall to the thickness of the upper flange and the lower flange is between 1.1-1.4.

[0008] Furthermore, the angle between the lowermost cut surface of the outer wall surface of the connecting side wall and the vertical direction is between 20-25°, and the angle between the lowermost cut surface of the inner wall surface of the connecting side wall and the vertical direction is between 13-18°.

[0009] Furthermore, the ratio of the distance from the lower end surface of the upper flange to the upper end surface of the lower flange in the vertical direction to the distance from the outer edge of the lower end surface of the upper flange to the inner edge of the upper end surface of the lower flange in the radial direction is between 0.6-0.7.

[0010] Furthermore, the upper flange includes a tower connection section and an upper rounded transition section, the lower flange includes a base connection section and a lower rounded transition section, the upper end of the connecting side wall is smoothly connected to the upper rounded transition section, and the lower end of the connecting side wall is smoothly connected to the lower rounded transition section.

[0011] Furthermore, a ratio of a radial width of an upper end surface of the tower connection section to a radial width of a lower end surface of the base connection section is between 0.6 and 0.8.

[0012] Furthermore, the foundation connection section is provided with two inner and outer circles of bolt holes, the tower connection section is provided with one circle of bolt holes, and the bolt holes of the tower connection section have a larger diameter than the bolt holes of the foundation connection section.

[0013] Furthermore, the transition section is integrally formed by integral casting or integral forging.

[0014] The transition section for wind turbine tower test of the present invention can realize the installation of wind turbine towers with different bottom diameters to the tower foundation flange of fixed size in the test wind field by setting a lower flange with a larger size and an upper flange with a relatively smaller size, thereby solving the adaptation problem of wind turbine towers of different sizes in a specific test wind field. The connecting side wall with an arc-shaped structure protruding outward is adopted between the upper flange and the lower flange, which has a strong load-bearing capacity; the connecting side wall is integrally formed with the upper flange and the lower flange, avoiding the defects caused by welding, and can improve the load-bearing capacity of the unit weight of the transition section. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following drawings of the present invention are used as part of the present invention for understanding the present invention. The drawings show the embodiments of the present invention and their descriptions, and are used to explain the device and principle of the present invention. In the drawings,

[0016] Figure 1 A three-dimensional diagram of a transition section for a wind turbine tower test according to an embodiment of the present invention;

[0017] Figure 2A top view of a transition section for a wind turbine tower test according to an embodiment of the present invention;

[0018] Figure 3 for Figure 2 AA section view in. DETAILED DESCRIPTION

[0019] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0020] In order to fully understand the present invention, a detailed structure will be presented in the following description to illustrate the present invention. Obviously, the implementation of the present invention is not limited to the specific details familiar to those skilled in the art. The preferred embodiments of the present invention are described in detail below, but in addition to these detailed descriptions, the present invention may also have other embodiments and should not be construed as being limited to the embodiments presented here.

[0021] It should be understood that the purpose of the terms used herein is only to describe specific embodiments and is not intended to limit the present invention. The singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. When the terms "comprise" and / or "include" are used in this specification, they indicate the presence of the features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof. The terms "upper", "lower", "front", "back", "left", "right" and similar expressions used in the present invention are for illustrative purposes only and are not limiting.

[0022] Ordinal numbers such as "first" and "second" cited in the present invention are merely identifications and do not have any other meanings, such as a specific order, etc. Moreover, for example, the term "first component" itself does not imply the existence of the "second component", and the term "second component" itself does not imply the existence of the "first component".

[0023] Hereinafter, specific embodiments of the present invention will be described in more detail with reference to the accompanying drawings. These drawings show representative embodiments of the present invention and do not limit the present invention.

[0024] The present invention provides a transition section for wind turbine tower testing. According to a preferred embodiment of the present invention, Figure 1-3As shown, the transition section includes a lower flange 1 for connecting to the tower foundation of the test wind farm, an upper flange 2 for connecting to the bottom flange of the tower, and a connecting side wall 3 located between the upper flange 2 and the lower flange 1, the lower end of the connecting side wall 3 is connected to the inner side of the lower flange 1, the upper end of the connecting side wall 3 is connected to the outer side of the upper flange 2, the outer contour of the connecting side wall 3 is configured as an arc structure that tapers from bottom to top and bulges outward, the wall thickness of the connecting side wall 3 is greater than the thickness of the upper flange 2 and the lower flange 1, and the lower flange 1, the upper flange 2 and the connecting side wall 3 are integrally formed by integral casting or integral forging.

[0025] The transition section of the present invention can realize the installation of wind turbine towers with different bottom diameters to the tower foundation flange of fixed size in the test wind farm by setting a lower flange with a larger size and an upper flange with a relatively smaller size, thereby solving the adaptation problem of wind turbine towers of different sizes in a specific test wind farm. A connecting side wall with an arc-shaped structure protruding outward is used between the upper flange and the lower flange. The connecting side wall is integrally formed with the upper flange and the lower flange, avoiding the defects caused by welding and improving the load-bearing capacity of the unit weight of the transition section.

[0026] According to an embodiment of the present invention, the outer wall surface 31 and the inner wall surface 32 of the connecting side wall 3 are both curved structures convex to the outside. Figure 3 As shown, the wall thickness of the connecting side wall 3 tapers from bottom to top. This arrangement can make the weight of the transition section lighter and save materials on the basis of meeting the bearing capacity.

[0027] Based on load analysis and combined with optimized design for weight and size, for the ratio of the bottom diameter of the tower to be tested to the diameter of the foundation anchor flange of the test wind farm is between 2:3-3:4, the transition section with the above structure achieves the best combination of load-bearing capacity and self-weight under the conditions that the ratio of the wall thickness of the lower end of the connecting side wall 3 to the wall thickness of the upper end is between 1.2-1.5, and the ratio of the wall thickness of the upper end of the connecting side wall 3 to the thickness of the lower flange 1 or the upper flange 2 is between 1.1-1.4. Preferably, the thickness of the lower flange 1 is the same as that of the upper flange 2.

[0028] Furthermore, when the angle between the lowest end section of the outer wall surface 31 connected to the side wall 3 and the vertical direction is between 20-25°, the angle between the lowest end section of the inner wall surface 32 connected to the side wall 3 and the vertical direction is between 13-18°, and the ratio of the distance h from the lower end surface of the upper flange 2 to the upper end surface of the lower flange 1 along the vertical direction to the distance s from the outer edge of the lower end surface of the upper flange 2 to the inner edge of the upper end surface of the lower flange 1 along the radial direction is between 0.6-0.7, the profile of the transition section can achieve the optimal load-bearing capacity on the basis of meeting the above-mentioned structural requirements.

[0029] According to an embodiment of the present invention, the upper flange 2 includes a tower connection section 21 and an upper rounded transition section 22, the lower flange 1 includes a base connection section 11 and a lower rounded transition section 12, the upper end of the connecting side wall 3 is smoothly connected to the upper rounded transition section 22, and the lower end of the connecting side wall 3 is smoothly connected to the lower rounded transition section 12. The upper and lower flanges and the connecting side wall are connected by rounded smooth transition, which is conducive to reducing stress concentration. Further, as Figure 3 As shown, the ratio of the radial width d1 of the upper end face of the tower connection section 21 to the radial width d2 of the lower end face of the base connection section 11 is between 0.6 and 0.8. Based on the load analysis of the transition piece, it can be concluded that when the upper flange and the lower flange meet the above-mentioned size conditions, the transition section has an overall stable stress state. Accordingly, the base connection section 11 with a relatively large area is provided with two inner and outer circles of bolt holes, and the tower connection section 21 with a relatively small area is provided with a circle of bolt holes, and the bolt hole diameter of the tower connection section 21 is larger than the bolt hole diameter of the base connection section 11.

[0030] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art in the technical field of the present invention. The terms used herein are only for describing specific implementation purposes and are not intended to limit the present invention. Terms such as "parts" and "pieces" appearing in this article may represent either a single part or a combination of multiple parts. Terms such as "installation" and "setting" appearing in this article may represent either a component being directly attached to another component or a component being attached to another component through an intermediate. Features described in this article in one embodiment may be applied to another embodiment alone or in combination with other features, unless the feature is not applicable in the other embodiment or otherwise specified.

[0031] The present invention has been described through the above-mentioned embodiments, but it should be understood that the above-mentioned embodiments are only for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the present invention is not limited to the above-mentioned embodiments, and more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the scope of the protection claimed by the present invention. The protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A transition section for wind turbine tower testing, characterized in that: The transition section includes a lower flange for connecting to the tower foundation of the test wind farm, an upper flange for connecting to the bottom flange of the tower to be tested, and a connecting side wall located between the upper flange and the lower flange, the lower end of the connecting side wall is connected to the inner side of the lower flange, the upper end of the connecting side wall is connected to the outer side of the upper flange, the outer contour of the connecting side wall is configured as an arc structure that tapers from bottom to top and bulges outward, the wall thickness of the connecting side wall is greater than the thickness of the upper flange and the lower flange, and the wall thickness of the connecting side wall tapers from bottom to top, and the upper flange, the lower flange and the connecting side wall are integrally formed.

2. The transition section according to claim 1, characterized in that: The outer wall surface and the inner wall surface connecting the side walls are both arc surface structures convex outwards.

3. The transition section according to claim 1, characterized in that: The ratio of the wall thickness of the lower end of the connecting side wall to the wall thickness of the upper end is between 1.2-1.5, and the ratio of the wall thickness of the upper end of the connecting side wall to the thickness of the upper flange and the lower flange is between 1.1-1.

4.

4. The transition section according to claim 1, characterized in that: The angle between the lowermost cut surface of the outer wall surface of the connecting side wall and the vertical direction is between 20-25 degrees, and the angle between the lowermost cut surface of the inner wall surface of the connecting side wall and the vertical direction is between 13-18 degrees.

5. The transition section according to claim 4, characterized in that: The ratio of the distance from the lower end surface of the upper flange to the upper end surface of the lower flange in the vertical direction to the distance from the outer edge of the lower end surface of the upper flange to the inner edge of the upper end surface of the lower flange in the radial direction is between 0.6 and 0.

7.

6. The transition section according to claim 1, characterized in that: The upper flange includes a tower connection section and an upper rounded transition section, the lower flange includes a base connection section and a lower rounded transition section, the upper end of the connecting side wall is smoothly connected to the upper rounded transition section, and the lower end of the connecting side wall is smoothly connected to the lower rounded transition section.

7. The transition section according to claim 6, characterized in that: The ratio of the radial width of the upper end surface of the tower connection section to the radial width of the lower end surface of the base connection section is between 0.6 and 0.

8.

8. The transition section according to claim 7, characterized in that: The foundation connection section is provided with two inner and outer circles of bolt holes, and the tower connection section is provided with one circle of bolt holes. The bolt holes of the tower connection section have a larger diameter than the bolt holes of the foundation connection section.

9. The transition section according to any one of claims 1 to 8, characterized in that: The transition section is integrally formed by integral casting or integral forging.

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