Air pocket separation-type floating offshore wind power generation structure and installation method thereof

Abstract

The present invention relates to a structure for offshore wind power generation and, more specifically, to an air pocket separation-type floating offshore wind power generation structure for installing a wind power generator at a floating offshore wind power generation site and an installation method thereof. To this end, the present invention comprises: an air pocket box structure having a wall that forms a surface configured to cover and seal an internal space of the air pocket box structure so as to maintain the airtightness of the internal space, and equipped with an air inlet / outlet device for filling or removing air; a freshwater box structure, located below the air pocket box structure, having a wall that forms a surface configured to cover and seal the internal space of the freshwater box structure so as to maintain the airtightness of the internal space, and equipped with a water inlet / outlet device for filling or removing water.

Description

Structure and installation method for floating offshore wind power generation with air pocket separation

[0001] The present invention relates to a structure for offshore wind power generation, and more particularly, to an air pocket-separated floating offshore wind power generation structure and installation method for installing a wind turbine in a floating offshore wind power generation.

[0002] In relation to global environmental issues, renewable energy power generation technologies that can replace fossil fuel-based power generation are continuously being researched, developed, and commercialized. As one important renewable energy source, the need for floating offshore wind power generation is increasing.

[0003] Furthermore, the importance of floating substructure technology is increasing for stable power generation operations in these floating offshore wind power plants. In other words, the production and installation of suitable floating substructures is essential for stable power generation operations in harsh marine environments.

[0004] To explain further, in general, for onshore wind power generation and fixed offshore wind power generation, there are difficulties in the site selection process, and the closer to land you get, the scarcer the available space becomes, and the sensitivity to environmental impacts increases.

[0005] In contrast, floating offshore wind power plants can be installed even in the open sea, making site selection relatively easy. They also have the advantage of being able to maintain strong and constant wind speeds due to less turbulence caused by obstacles, and securing a high utilization rate of wind turbines based on this excellent wind quality.

[0006] However, unlike other types of wind power generation, floating offshore wind power must support large loads while floating and remain stable in a highly variable marine environment, which increases the importance of floating substructures. These substructures can be generally categorized into spar, semi-submersible, tension-leg-platform, and barge types. Hywind Scotland, an early floating offshore wind power project, adopted a spar type for its high stability. However, since the cylinders were erected and installed using a crane, there were problems with water depth restrictions and high costs due to crane vessel rental. Tension-leg platforms also offer high stability, but their installation costs are very high, resulting in a relatively high overall cost. Conversely, barge-type platforms have lower installation and manufacturing costs, but their stability is relatively low.

[0007] Meanwhile, the semi-submersible type has the advantage of being easy to install as it is less affected by the installation location and weather conditions, and thus many projects currently scheduled for development are adopting the semi-submersible type because it has the advantage of being easy to install as it can be installed by developing the Tetraspar structure to reduce the burden of manufacturing costs or by developing the TELWIND structure to use a tugboat to install it.

[0008] However, even in semi-submersible structures, since steel materials and welding construction are mainly used, the material and construction costs are still considerable, and since wind turbines are not usually installed in the center of the structure, there is a problem that it is not easy to stably balance construction and maintenance in various weather and marine environments.

[0009] The present invention is intended to improve the problems of the existing floating offshore wind power generation structures described above, and to provide a floating offshore wind power generation structure and installation method having a configuration that can be manufactured at a relatively low cost and easily installed compared to the existing structure.

[0010] The purpose of the present invention is to provide a structure and installation method for floating offshore wind power generation suitable for stably constructing and maintaining floating offshore wind power generation facilities.

[0011] In order to achieve the above object, the present invention provides an air pocket-separated floating offshore wind power generation structure, which comprises an air pocket box structure having a wall forming a surface that can cover and seal an internal space so as to maintain the airtightness of the internal space, and having an air inlet / outlet device capable of filling or removing air; and a freshwater box structure located below the air pocket box structure, having a wall forming a surface that can cover and seal an internal space so as to maintain the airtightness of the internal space, and having a water inlet / outlet device capable of filling or removing water.

[0012] In addition, it is characterized by further comprising a reinforcing skeletal structure for supporting the air pocket box structure and the freshwater box structure.

[0013] In addition, the reinforcing skeleton structure is characterized by including a column formed vertically to support the air pocket box structure and the freshwater box structure by connecting them to each other; and a beam (including an aerial beam) formed horizontally to support the internal space of the air pocket box structure and the freshwater box structure.

[0014] In addition, a wind turbine is installed above the air pocket box structure, and a central pipe is formed in the center of the air pocket box structure and the freshwater box structure, penetrating the air pocket box structure and the freshwater box structure.

[0015] The method for installing an air pocket separation type floating offshore wind power generation structure according to the present invention is characterized by including the steps of: manufacturing the air pocket separation type floating offshore wind power generation structure on land; towing the air pocket separation type floating offshore wind power generation structure on water to an installation location (position) at sea; introducing seawater into a freshwater box structure until the lower surface of the air pocket box structure touches the sea surface; and installing a wind power generator above the air pocket box structure.

[0016] The air pocket-separated floating offshore wind power generation structure according to the present invention can be manufactured at a relatively low cost and easily installed compared to existing structures, thereby reducing the overall construction cost and effort of the floating offshore wind power generation facility.

[0017] According to the present invention, a floating offshore wind power generation facility can be constructed and maintained more stably than before through an air pocket separation type floating offshore wind power generation structure.

[0018] Figure 1 is a plan view of a floating offshore wind power generation structure with an air pocket separation type according to one embodiment of the present invention.

[0019] Figure 2 is a drawing showing the positions of the side wall and the beams, aerial beams, and joints on the inner surface thereof in a cross-section cut by a horizontal plane passing through the line AA of Figure 1.

[0020]

[0021] 100: Floating offshore wind power generation structure

[0022] 110: Air pocket box structure

[0023] 120: Freshwater box structure

[0024] 11, 12, 13, 14: See

[0025] 15: Public information

[0026] 130: Pillar

[0027] 140: Joint

[0028] 150: Base Plate

[0029] 160: Central pipe

[0030] 200: Wind turbine

[0031] 310: Fixture for floating body

[0032] 320: Fixed cable

[0033] 410: Drain valve

[0034] 420: Freshwater valve

[0035] 430: Air valve

[0036]

[0037] The above-described purposes, other purposes, features, and advantages of the present invention will be readily understood through the following preferred embodiments, illustrated in the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosure is thorough and complete, and to ensure that the spirit of the present invention is fully conveyed to those skilled in the art.

[0038] Additionally, the terminology used herein is for the purpose of describing embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise. As used herein, the terms "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components.

[0039] Hereinafter, the specific technical contents to be implemented in the present invention will be described in detail with reference to the attached drawings.

[0040] FIG. 1 is a plan view of an air pocket-separated floating offshore wind power generation structure according to an embodiment of the present invention. As illustrated in FIG. 1, an air pocket-separated floating offshore wind power generation structure (100) according to the present invention comprises an air pocket box structure (110) and a freshwater box structure (120).

[0041] The above air pocket box structure (110) can cover and seal the internal space so as to maintain the airtightness of the internal space, and the wall forming the surface is composed of a lower wall, four side walls, and an upper wall.

[0042] The above freshwater box structure (120) can cover and seal the internal space by forming a wall that forms the surface so as to maintain the airtightness of the internal space, and the wall is composed of a lower wall, four side walls, and an upper wall.

[0043] In addition, as illustrated in FIG. 2, a beam is formed horizontally on the inner surface of each wall facing the interior space. A column (130) formed vertically is positioned between the beams of the upper and lower walls, and a horizontally formed air beam (15) is positioned between the beams of the inner surfaces of the side walls facing each other. A joint (140) is installed at the portion where the column (130) and the air beam (15) meet each other in space. FIG. 2 is a diagram illustrating the positions of the beams, air beams, and joints of the side wall and its inner surface in a cross-section cut by a horizontal plane passing through the line AA of FIG. 1.

[0044] A structure composed of such columns (130) and beams (15) may appear similar to a frame structure or steel structure without a slab. Here, there is one joint (140) between the beam (13) of the upper wall and the beam (11) of the lower wall, but the number of these joints (140) may increase to two or more depending on the size or thickness of the structure. Similarly, there are six joints (140) along the beams (15) extending horizontally in a straight line between the opposing side walls, but the number of these joints (140) may also be a different number depending on the size or width of the structure.

[0045] Walls, beams, columns, and skylights can all be constructed integrally from reinforced concrete, or each element can be formed and joined in different ways. For example, walls can be constructed of reinforced concrete, while columns and skylights can be constructed of steel-framed concrete, with concrete encasing the steel frame. They can also be constructed of hollow square steel tubes, with concrete encasing the outside of the tubes, or they can be constructed of two square steel tubes of different sizes, with concrete filling the space between them.

[0046] The above pillar (130) also serves to support and connect the air pocket box structure (110) and the freshwater box structure (120) to each other. To this end, the pillar is formed to penetrate the lower surface of the air pocket box structure (110) and the upper surface of the freshwater box structure (120), and can be connected to the beam (14) of the upper wall of the air pocket box structure (110).

[0047] Here, a base plate (150) on which a wind turbine tower is installed is installed in the center of the upper wall of the air pocket box structure (110). A central conduit (160) is formed below the base plate (150) to connect the upper and lower walls of the air pocket box structure (110) and the upper and lower walls of the freshwater box structure (120). The wall forming the central conduit (160) can serve as a kind of pillar in this structure, and can support the weight of the wind turbine placed thereon more stably while distributing the weight, and unlike this embodiment, it can also have a configuration in which it is connected to aerial beams.

[0048] An air valve (430) is also installed in the air pocket box structure (110) of the air pocket separation type floating offshore wind power generation structure, and a drain valve (410) and a fresh water valve (420) are installed in the fresh water box structure (120).

[0049] The drain valve (410), fresh water valve (420), and air valve (430) may be configured by a pipe connecting the internal space and the external space of the structure, and a pump installed along the pipe path. It is preferable that the pump be bidirectionally driven to allow both filling and removing air or water from the internal space.

[0050] In addition, although not shown here, a management access device (not shown) such as a separate inspection hole may be installed on the upper part of this structure to manage the space inside this structure, and this management access device must be configured to prevent air in the upper space from escaping unintentionally.

[0051] Meanwhile, this structure is equipped with mooring facilities to prevent it from drifting in the sea and leaving a certain location range.

[0052] The mooring facility may be composed of a subsea fixture (not shown), a floating fixture (310) coupled to the structure, and a fixing cable (320) that connects and couples the subsea fixture and the floating fixture (310). The floating fixture (310) is illustrated here as being installed in four pieces, one at each lower vertex of the rectangular solid of the freshwater box structure (120), but may be installed in an appropriate number at an appropriate location considering the overall size and weight of the structure, the mechanical durability and strength of the cables and fixtures, etc. Since such mooring facilities are already well known, further detailed description thereof will be omitted here.

[0053] And, although not shown here, the power generated from the wind turbine (200) must be connected to an adjacent power network via a wire cable connected to the wind turbine. The power network may be a substation including an inverter installed on an adjacent offshore structure, and a land-based power facility that receives the power converted by the substation via a submarine wire cable. Since power facilities such as wire cables and communication line cables are typically connected to surrounding facilities via the seabed, such cables must be laid to extend from the wind turbine (200) to the seabed. For this purpose, it is preferable to use the central conduit (160) at the bottom of the wind turbine (200) tower. That is, the structure and the wind turbine can be combined and installed so that separate mooring cables, communication line cables, and power cables pass through the central conduit (160).

[0054] Next, the manufacturing and installation (installation of a wind power generation facility) of the structure of the present invention having such a configuration will be described.

[0055] First, the structure is designed in terms of the size of the air pocket-separated floating offshore wind turbine structure and the structure of the internal reinforcing elements according to the capacity of the wind turbine. In the above embodiment, a vertical column (130), horizontal beams (11, 12, 13, 14), and an air beam (15) are simply installed in the internal space of the rectangular parallelepiped wall, and a joint (140) is provided at the point where the air beam (15) and the column (130) meet. However, the specific shape of the box and the reinforcing structure for maintaining the internal space can utilize various structures known in existing construction.

[0056] Also, from a material perspective, the above embodiment can utilize various materials and their combinations known in conventional construction in addition to conventional reinforced concrete structures.

[0057] With regard to construction, the structure of the present invention can generally be constructed on land, particularly in docks used for shipbuilding. While the materials and methods used to construct elements such as walls, columns, beams, aerial beams, and joints may vary, if these elements are formed of reinforced concrete, the construction of the structure can be similar to the construction of a reinforced concrete building. For example, the construction can be carried out by constructing a frame, placing reinforcing bars within the frame, and then filling the frame with concrete.

[0058] Additionally, mooring fixtures for the floating bodies required for the structure will be manufactured, along with anchoring cables. If mechanical strength can be secured at the sealing and connection points, this structure can also be manufactured in blocks, similar to how large vessels are constructed by manufacturing individual sections as blocks and then joining them together to form the entire structure.

[0059] Once the concrete has sufficiently cured, and auxiliary equipment such as fresh water valves, drain valves, and air valves have been installed, and the structure has been constructed so that the internal space can be sealed, the box-shaped structure can be towed to the installation location of the wind turbine with the fresh water valves, drain valves, and air valves closed, and then supported by a marine crane, etc.

[0060] After towing to the installation location, seawater is introduced through the freshwater valve of the freshwater box structure until the lower surface of the air box structure touches the sea surface, and then the structure is supported by a marine crane, etc.

[0061] The air pocket-separated floating offshore wind power generation structure discussed above has a simple structure and is constructed using simple and clear principles. It can be manufactured very economically using inexpensive concrete among various materials, which has the advantage of minimizing the construction cost of floating offshore wind power generation facilities.

[0062] In addition, since this structure can be manufactured in a stable onshore environment rather than at sea, it is easy to ensure product reliability, and since it is a sealed box-shaped structure, the structure can be towed to the location where the wind turbine is installed while floating on the sea, thereby reducing the cost of transporting the structure.

[0063] In particular, this structure is in the shape of a rectangular box, and if it is manufactured with a low height compared to the area, it is more stable, can be manufactured and maintained, and it is easy to install a wind turbine tower on the flat and wide top of the box, and since the structure is simple and easy to construct, construction costs can be minimized.

[0064] In addition, as in one aspect of the present invention, if a central conduit is installed that vertically penetrates the central portion of the floating box structure, i.e., below the wind turbine tower installation portion, transmission and distribution cables, etc. connected from the wind turbine tower can be directly connected to the seabed.

[0065] Additionally, because the floating box structure is filled with seawater with the same specific gravity as the seawater at the location where the wind turbine is installed, it can be more stable against wave currents.

[0066] Although the present invention has been described above through limited examples, these are merely illustrative examples to help understanding of the present invention, and the present invention is not limited to these specific examples.

[0067] Accordingly, a person having ordinary knowledge in the field to which the invention pertains will be able to make various modifications or applications based on the present invention, and it is natural that such modifications or applications fall within the scope of the appended patent claims.

Claims

1. An air pocket box structure having a wall surface that can cover and seal the internal space so as to maintain the airtightness of the internal space, and an air inlet / outlet device that can fill or remove air; and A freshwater box structure located at the bottom of the above air pocket box structure, having a wall forming a surface that can cover and seal the internal space so as to maintain the airtightness of the internal space, and having a water inlet device capable of filling or draining water; A floating offshore wind power generation structure characterized by including an air pocket separation structure.

2. In paragraph 1, An air pocket-separated floating offshore wind power generation structure characterized by further comprising a reinforcing frame structure for supporting the air pocket box structure and the freshwater box structure.

3. In paragraph 2, The above reinforcing skeleton structure is, A column formed vertically to support and connect the above air pocket box structure and the freshwater box structure to each other; and A beam (including an aerial beam) formed horizontally to support the internal space of the above air pocket box structure and freshwater box structure; A floating offshore wind power generation structure characterized by including an air pocket separation structure.

4. In paragraph 1, A wind turbine is installed above the above air pocket box structure. An air pocket separation type floating offshore wind power generation structure, characterized in that a central conduit is formed in the center of the air pocket box structure and the freshwater box structure, penetrating the air pocket box structure and the freshwater box structure.

5. A method for installing an air pocket-separated floating offshore wind power generation structure according to any one of clauses 1 to 4, A step for manufacturing the above air pocket-separated floating offshore wind power generation structure on land; A step of floating the above air pocket-separated floating offshore wind power generation structure on water and towing it to the installation site (location) at sea; A step of introducing seawater into the freshwater box structure until the lower surface of the air pocket box structure reaches the sea surface; and A step of installing a wind turbine above the above air pocket box structure; A method for installing an air pocket-separated floating offshore wind power generation structure, characterized by including a .

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