Floating structure and offshore wind power generation apparatus comprising same

Abstract

A floating structure is disclosed. A floating structure according to an embodiment of the present invention comprises: a center column to which a tower including an offshore wind power nacelle is connected; pontoons each having a plurality of sides and connected to the center column; outer columns each arranged between the plurality of sides of the pontoons; and connection members connecting the pontoons and the center column, wherein the pontoon comprises concrete portions, in the plurality of sides, connected to the outer columns and forming both end portions of the plurality of sides, and a steel material portion disposed between the concrete portions at both end portions of the plurality of sides and connecting the concrete portions arranged at the both end portions of the plurality of sides. The connection member is coupled to the steel material portion such that the pontoons can be connected to the center column.

Description

Floating structure and offshore wind power device having the same

[0001] The present disclosure relates to a floating structure and an offshore wind power device having the same, and more specifically, to a floating structure that floats on the sea and supports equipment positioned on top of it, and an offshore wind power device having the same.

[0002] Wind power generation is a technology that produces electricity by converting wind energy into mechanical energy, and it is gaining attention as a clean energy source for reducing greenhouse gases. While these wind turbines are primarily installed on land, onshore installations present challenges such as noise issues and land acquisition difficulties. Consequently, there has been a recent increase in the trend of installing wind turbines offshore.

[0003] One type of offshore wind power generation device is the floating wind turbine, which is installed by floating on the seabed. Such floating wind turbines have the advantage of being installable regardless of water depth. Additionally, they offer the advantage of being installable in deep open waters to maximize power generation efficiency by utilizing strong winds.

[0004] In a floating wind power generation device, power generation equipment is positioned on the upper part, and a floating structure to support said equipment is positioned on the lower part.

[0005] These floating structures are the most critical components in terms of ensuring motion stability. Floating structures are primarily being developed in the form of hulls constructed entirely of steel or concrete. While concrete hulls are competitive in terms of manufacturing costs compared to steel hulls, their heavy weight poses difficulties in installing turbines and towers at fabrication yard quays in shallow waters.

[0006] One aspect of the present disclosure discloses a floating structure that uses a mixture of concrete and steel to reduce its own weight compared to a floating structure made of only concrete and has excellent safety, and an offshore wind power device having the same.

[0007] According to an embodiment of the present disclosure, a floating structure comprises a center column to which a tower including an offshore wind turbine nacelle is connected, a pontoon having a plurality of sides connected to the center column, an outer column disposed between the plurality of sides of the pontoon, and a connecting member connecting the pontoon and the center column, wherein the pontoon includes a concrete portion connected to the outer column on the plurality of sides and forming both ends of the plurality of sides, and a steel portion disposed between the concrete portions disposed at both ends of the plurality of sides and connecting the concrete portions disposed at both ends of the plurality of sides, and the connecting member is coupled to the steel portion so that the pontoon is connected to the center column.

[0008] It further includes an anchor provided to be fixed to the seabed and a mooring line connecting the anchor and the floating structure, wherein the mooring line is provided to be connected to the steel portion.

[0009] The plurality of sides of the above pontoon include three sides, and the concrete part includes a first concrete part, a second concrete part, and a third concrete part formed between the three sides, respectively, and the first concrete part, the second concrete part, and the third concrete part are provided with the same shape.

[0010] The first concrete section, the second concrete section, and the third concrete section are each symmetrically arranged around the center column.

[0011] The first concrete part, the second concrete part, and the third concrete part are each arranged to be interchangeably combined with the steel part.

[0012] In the plurality of sides, the length of the steel portion in the extension direction of each side is provided to be 1 / 20 to 9 / 10 relative to the length of each side.

[0013] The above pontoon further includes a brace provided to additionally support the center column, and the brace is provided to be coupled to the steel member and extend to the center column.

[0014] According to an embodiment of the present disclosure, the safety of a floating structure can be improved while reducing the total weight of the floating body applied solely to concrete.

[0015] FIG. 1 is a perspective view illustrating an offshore wind power device according to one embodiment of the present disclosure.

[0016] FIG. 2 is a perspective view of a floating structure of an offshore wind power device according to one embodiment of the present disclosure.

[0017] FIG. 3 is a plan view of a floating structure of an offshore wind power device according to one embodiment of the present disclosure.

[0018] FIG. 4 is a perspective view of a floating structure of an offshore wind power device according to another embodiment of the present disclosure.

[0019] FIG. 5 is a side view of a floating structure of an offshore wind power device according to another embodiment of the present disclosure.

[0020] The embodiments described in this specification are merely the most preferred embodiments of the present invention and do not represent all technical concepts of the present invention; therefore, it should be understood that various equivalents or modifications that can replace them at the time of filing this application are also included within the scope of the rights of the present invention.

[0021] Singular expressions used in the description may include plural expressions unless the context clearly indicates otherwise. In the drawings, the shapes and sizes of elements may be exaggerated to provide a clearer description.

[0022] In this specification, terms such as "comprising" or "having" are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not excluding in advance the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0023] Throughout the specification, ordinal expressions such as “first” and “second” are used to distinguish multiple components from one another, and the ordinals used do not indicate the order of placement, manufacturing order, or importance among the components.

[0024] When it is stated that a component is "connected" to another component, it should be understood that it may be directly connected to that other component, or that there may be other components in between.

[0025] FIG. 1 is a perspective view illustrating an offshore wind power device according to one embodiment of the present disclosure, FIG. 2 is a perspective view of a floating structure of an offshore wind power device according to one embodiment of the present disclosure, and FIG. 3 is a plan view of a floating structure of an offshore wind power device according to one embodiment of the present disclosure.

[0026] Referring to FIGS. 1 and 2, a floating offshore wind power device (10) according to one embodiment of the present disclosure includes a power generation facility (20), a floating structure (100) that supports the power generation facility (20) while floating on the sea, and a mooring facility (30).

[0027] The power generation facility (20) may include a tower (21), a nacelle (22) installed on the upper part of the tower (21), and a rotor (23) connected to the rotation axis of the nacelle (22). The nacelle (22) is a device that converts wind power into mechanical rotational energy, and may have an electric generator built inside.

[0028] The rotor (23) may include a hub (23a) rotatably coupled to an electric generator and a plurality of blades (23b) coupled to the hub (23a) and extending radially. The electric generator may be connected to a power grid via an underwater power cable.

[0029] The power generation facility (20) of this embodiment is described as a horizontal axis power generation facility in which the rotation axis is parallel to the sea surface, but the power generation facility (20) may be configured as a vertical axis power generation facility in which the rotation axis is perpendicular to the sea surface.

[0030] The mooring facility (30) is a device for anchoring the floating structure (100) to the seabed.

[0031] The mooring facility (30) may include a mooring line (31) and an anchor (32).

[0032] The mooring line (31) can moor the floating structure (100) to the sea by connecting the floating structure (100) and the anchor (32).

[0033] The mooring line (31) can be composed of chains, ropes, steel wires, etc., and can be of the catenary type or tension leg type.

[0034] The floating structure (100) may include a center column (110) that supports the tower (21).

[0035] The floating structure (100) may include a pontoon (120) connected to the center column and a side (121). The side (121) may be provided in multiple numbers.

[0036] The pontoon (120) may be provided in a shape formed by a plurality of sides (121), including a plurality of sides (121). For example, the pontoon (120) may be provided in a triangular shape having three sides (121a, 121b, 121c). However, it is not limited thereto and may be provided in various shapes through the plurality of sides (121). For example, the pontoon (120) may include four sides to form a square shape or include more sides.

[0037] The floating structure (100) may include outer columns (130) positioned at both ends of the sides (121) of the pontoon (120). Multiple outer columns (130) may be provided.

[0038] The outer column (130) can be placed at each connection point of the plurality of sides (121). For example, the outer column (130) can be provided as three outer columns (130a, 130b, 130c) to be placed at the vertex portion of the triangular shape formed by three sides (121a, 121b, 121c).

[0039] The outer column (130) can be provided in the same number as the number of sides.

[0040] Multiple outer columns (130a, 130b, 130c) may be composed of cylindrical floating bodies. Multiple outer columns (130a, 130b, 130c) may be composed of floating bodies having polygonal cross-sections, such as squares or hexagons. Multiple outer columns (130a, 130b, 130c) may have the same shape and size.

[0041] The center column (110) may be located in the center of the pontoon (120), and the outer column (130) may be located on the outer edge of the pontoon (120). For example, the center column (110) may be placed at the center of the triangular pontoon (120), and the three outer columns (130a, 130b, 130c) may be placed at the triangular ends of the pontoon (120).

[0042] For example, a first outer column (130a) may be placed between the first side (121a) and the second side (121b), a second outer column (130b) may be placed between the second side (121b) and the third side (121c), and a third outer column (130c) may be placed between the third side (121c) and the first side (121a).

[0043] The floating structure (100) may include a connecting member (140) connecting the pontoon (120) and the center column (110). The connecting member (140) may be provided so that the center column (110) is supported by the pontoon (120).

[0044] The connecting member (140) may be provided as a component of the pontoon (120), but is not limited thereto, and the connecting member (140) may connect each component as an independent member to the pontoon (120) and the center column (110).

[0045] The floating structure (100) may include a brace (150) that reinforces rigidity by additionally connecting the pontoon (120) and the central column (110).

[0046] The pontoons of existing floating structures were formed of concrete or steel.

[0047] When forming a pontoon with concrete, the volume and weight of the pontoon increase to ensure rigidity, which leads to problems with manufacturing costs and environmental pollution due to high carbon emissions. In addition, as the self-weight of the pontoon increases while the buoyancy of the outer columns is maintained, a problem may arise in which bending stress occurs in the center of the pontoon.

[0048] Conversely, if pontoons are formed using steel, problems may arise regarding the economic feasibility of the steel and the cost of production due to material supply issues.

[0049] To prevent this, the pontoon (120) of the floating structure (100) according to an embodiment of the present invention is formed by using a mixture of concrete and steel, thereby solving the problem that occurs when the pontoon is formed only with concrete or steel.

[0050] The pontoon (120) may include a concrete section (125, 126, 127) formed of concrete and positioned adjacent to the outer column (130), and a steel section (129) formed of steel and positioned between the concrete sections (125, 126, 127).

[0051] The side (121) of the pontoon (120) may be composed of concrete sections (125, 126, 127) that are positioned at both ends of the side (121) and form the ends of the side (121), and a steel section (129) that is positioned between the concrete sections (125, 126, 127) formed at both ends of the side (121) and forms the center of the side (121). The steel section (129) may connect the concrete sections (125, 126, 127) positioned at both ends of the side (121) of the pontoon (120) in the direction of extension of the side (121).

[0052] More specifically, based on the first side (121a) of the pontoon (120), a first concrete section (125) adjacent to the first outer column and a third concrete section (127) adjacent to the third outer column (130c) may be arranged at each end of the first side (121a). Based on the first side (121a) of the pontoon (120), a first steel section (129a) may be arranged between the first concrete section (125) and the third concrete section (127).

[0053] Based on the second side (121b) of the pontoon (120), a first concrete section (125) adjacent to the first outer column (130a) and a second concrete section (126) adjacent to the second outer column (130b) may be arranged at each end of the second side (121b). Based on the second side (121b) of the pontoon (120), a second steel section (129b) may be arranged between the first concrete section (125) and the second concrete section (126).

[0054] Based on the third side (121c) of the pontoon (120), a third concrete section (127) adjacent to the third outer column (130c) and a second concrete section (126) adjacent to the second outer column (130b) may be arranged at each end of the third side (121c). Based on the third side (121c) of the pontoon (120), a third steel section (129c) may be arranged between the third concrete section (127) and the second concrete section (126).

[0055] For example, the first side (121a) of the pontoon (120) may be formed by a first part (125a) of a first concrete part (125) forming one end of the first side (121a), a first part (127a) of a third concrete part (127) forming the other end, and a first steel part (129a) positioned between the first part (125a) of the first concrete part (125) and the first part (127a) of the third concrete part (127) and forming the center of the first side (121a).

[0056] The concrete sections (125, 126, 127) are each provided to be connected to the outer column (130), and each concrete section (125, 126, 127) may be provided to form at least two side ends.

[0057] For example, the first part (125a) of the first concrete part (125) may form one end of the first side (121a), and the second part (125b) of the first concrete part (125) may form one end of the second side (121b).

[0058] The concrete sections (125, 126, 127) may each be connected to the outer column (130) or formed integrally. That is, the outer column (130) may be formed of concrete material and may be formed integrally with the concrete sections (125, 126, 127).

[0059] When the outer column (130) and the concrete section (125, 126, 127) are formed integrally, the outer column may be provided as part of the concrete section (125, 126, 127). The concrete section (125, 126, 127) may be formed from the end of the side (121) and the outer column (130).

[0060] That is, the outer column (130) is formed of concrete, and the ends of the two sides (121) connected to the outer column (130) can also be formed of concrete. The outer column (130) and the ends of the two sides (121) can be formed integrally to form a single concrete section (125, 126, 127).

[0061] The first concrete section (125) can be formed by the first outer column (130a) and the ends of the first side (121a) and the second side (121b).

[0062] The second concrete section (126) can be formed by the second outer column (130b) and the ends of the second side (121b) and the third side (121c).

[0063] The third concrete section (127) can be formed by the third outer column (130c) and the ends of the first side (121a) and the third side (121c).

[0064] The first concrete section (125), the second concrete section (126), and the third concrete section (127) can each be provided with the same shape. Since each concrete section (125, 126, 127) is provided with the same shape, they can be arranged to intersect each other, and they can be modularized so that other concrete sections with the same shape as each concrete section (125, 126, 127) and concrete sections (125, 126, 127) can also be placed at the location of each concrete section (125, 126, 127).

[0065] That is, each concrete part (125, 126, 127) is provided with the same structure, and below, the first concrete part (125) is described as the concrete part (125).

[0066] The first steel section (129a), the second steel section (129b), and the third steel section (129c) can each be provided with the same shape. Since each steel section (129a, 129b, 129c) is provided with the same shape, they can be arranged to intersect each other, and they can be modularized so that each steel section (129a, 129b, 129c) and other steel sections with the same shape as the steel sections (129a, 129b, 129c) can also be placed at the location of each steel section (129a, 129b, 129c).

[0067] That is, each steel part (129a, 129b, 129c) is provided with the same structure, and below, the first steel part (129a) is described as the steel part (129).

[0068] In addition, the three outer columns (130a, 130b, 130c) are provided with the same shape, so below, the first outer column (130a) is described as the outer column (130).

[0069] To maximize the advantages of concrete and steel, a pontoon (120) can be formed by mixing steel and concrete. A steel-concrete mixed floating structure (100) can be formed by mixing steel, which has high strength relative to weight, and concrete, which has relatively low strength but is easy to supply and manufacture.

[0070] In a floating structure (100), steel is arranged to be placed at locations where high stress and complex loads occur, and concrete is placed at locations where low stress and compressive loads occur, thereby improving the strength and stability of the floating structure (100).

[0071] The steel portion (129) of the pontoon (120) performs the role of distributing the load transmitted from the center column (110) to the concrete portion (125) of the pontoon (120) instead of directly transmitting it, thereby improving the stability of the floating structure (100).

[0072] As the steel member (129) is placed together with the concrete member (125), the total weight of the pontoon (120) is reduced, and the imbalance between the self-weight and buoyancy of the pontoon (120) is reduced, thereby performing the role of reducing loads such as moment or shear force acting on the pontoon (120).

[0073] For example, as the steel member (129) is positioned at the center of the side (121) of the pontoon (120) so that the center of the side (121) is formed of steel rather than concrete, the rigidity against the bending moment that can be transmitted to the center of the side (121) can be secured.

[0074] In addition, the steel member (129) can reduce the magnitude of tensile stress that can be applied to the concrete member (125) of the pontoon (120), thereby enabling easy design of the volume or shape of the concrete member (125) in the pontoon (120).

[0075] The connecting member (140) may be made of steel. The connecting member (140) connects the center column (110) and the pontoon (120) with steel to maximize rigidity against the load transmitted from the center column (110).

[0076] The connecting member (140) can be provided to be connected to the steel portion (129) of the pontoon (120).

[0077] The load from the center column (110) transmitted from the connecting member (140) is designed to be received through the steel section (129), thereby dispersing the load transmitted from the center column (110) rather than directly transmitting it to the concrete section (125), which can improve the overall rigidity of the pontoon (120) and improve the stability of the floating structure (100).

[0078] The brace (150) can be provided to be connected to the steel portion (129) of the pontoon (120).

[0079] The load from the center column (110) transmitted from the brace (150) is designed to be received through the steel section (129), thereby dispersing the load transmitted from the center column (110) rather than directly transmitting it to the concrete section (125), so that the overall rigidity of the pontoon (120) can be improved.

[0080] The mooring line (31) may be provided to be connected to the steel portion (129) of the pontoon (120). For example, the mooring line (31) may be provided to be connected to a fairlead (34) formed on the steel portion (129). For example, the fairlead (34) and the steel portion (129) may be formed integrally.

[0081] The external force that can be transmitted from the mooring line (31) is designed to be received through the steel section (129), so that the external force is not transmitted directly to the concrete section (125) but is distributed, thereby improving the overall rigidity of the pontoon (120).

[0082] For example, the rigidity can be improved by forming the fairlead (34) and the steel part (129) as a single unit of steel.

[0083] That is, the part connecting the external components of the pontoon (120) and the pontoon (120) is configured to be connected at the steel section (129), so that the steel section (129) receives various external forces and loads that can be transmitted from the external components first. As the steel section (129) has higher rigidity compared to the concrete section (125), the overall rigidity of the pontoon (120) can be improved.

[0084] The length (d2) of the steel portion (129) in the extension direction of the side (121) can be provided with a length of 1 / 20 to 9 / 10 relative to the length (d1) of the side (121) of the pontoon (120).

[0085] The steel section (129) is designed such that a portion of the concrete section (125) is replaced from concrete to steel, and its length can be designed based on the magnitude of the tensile stress acting on the concrete section (125) of the pontoon (120).

[0086] In addition, the length of the steel member (129) can be designed based on the magnitude of the external force or external load at the location where the external components of the pontoon (120) are connected.

[0087] Considering the magnitude of the tensile stress acting on the concrete part (125) of the pontoon (120), the ratio of the length (d2) of the steel part (129) of the pontoon (12) to the length (d1) of the side (121) of the pontoon (120) can preferably be set between 1 / 20 and 9 / 10.

[0088] As described above, each concrete part (125, 126, 127) and each steel part (129a, 129b, 129c) are formed identically, so that modularization is possible in manufacturing the floating structure (200).

[0089] For example, the second concrete section (126) and the third concrete section (127) may be arranged to be formed at the location where the first concrete section (125) is formed. This is because even if any one of the first concrete section (125), the second concrete section (126), or the third concrete section (127) is placed and assembled at the location where each concrete section (125, 126, 127) is assembled, each concrete section (125, 126, 127) is formed identically and can be fastened and joined with the same structure as the steel section (129).

[0090] In addition, the pontoon (120) can be manufactured with the same shape even if any one of the first steel part (129a), the second steel part (129b), and the third steel part (129c) is placed and assembled at the location where each steel part (129a, 129b, 129c) is assembled.

[0091] Therefore, when manufacturing the pontoon (120), the pontoon (120) can be assembled with three identical steel parts (129) and three identical concrete parts (125, 126, 127), and accordingly, the mass production and manufacturing efficiency of the pontoon (120) can be improved.

[0092] Hereinafter, a floating structure (200) according to another embodiment is described. Except for the components additionally described below, the components are identical to the structure of the floating structure (100) according to the above-described embodiment, so redundant descriptions are omitted.

[0093] FIG. 4 is a perspective view of a floating structure of an offshore wind power device according to another embodiment of the present disclosure, and FIG. 5 is a side view of a floating structure of an offshore wind power device according to another embodiment of the present disclosure.

[0094] The mooring line (31) can be arranged to be connected to the upper part of the outer column (130).

[0095] To improve the ease of work such as replacing the mooring line (31), the mooring line (31) may be provided to be connected to the upper part of the outer column (130).

[0096] The upper part of the outer column (130) can be arranged to be positioned above the sea level when the floating structure (200) is floating on the sea.

[0097] The floating structure (200) may include a steel cap (35) formed of steel and positioned on top of the outer column (130).

[0098] The mooring line (31) may be provided to be connected to the steel cap (35). The mooring line (31) may be provided to be connected to the fairlead (34) formed on the steel cap (35).

[0099] The steel cap (35) may be provided to cover the top of the outer column (130) and at least a portion of the outer column (130) extending from the top to the bottom.

[0100] The upper part of the outer column (130) can be arranged to be inserted into the steel cap (35).

[0101] By placing a steel cap (35) formed of steel at the part connected to the mooring line (31), rigidity against external forces transmitted through the mooring line (31) can be secured through the steel. In addition, the stability of the pontoon (120) can be improved by distributing and transmitting the load transmitted from the outside to the outer column (130) formed of concrete.

[0102] In addition, as the steel cap (35) is positioned on the upper part of the outer column (130), work such as replacing the mooring line (31) can be carried out above the sea surface, making it easy to repair and maintain the mooring line (31).

[0103] In the case of the above-described floating structure (100), the mooring line, connecting member (140), and brace (150) are all connected to the steel part (129), so a problem may occur where the load is concentrated on the steel part (129). However, in the floating structure (200) according to one embodiment of the present invention, the mooring line (31) is connected to the steel cap (35), so the load concentrated on the steel part (129) can be dispersed.

[0104] The height (h2) of the steel cap (35) in the height direction of the outer column (130) can be provided at a height of 1 / 20 to 1 / 2 compared to the height (h1) of the outer column (130).

[0105] The height (h2) of the steel cap (35) can be made higher than the size of the components such as the fairlead (34) connected to the steel cap (35).

[0106] The height (h2) of the steel cap (35) can be determined according to the magnitude of the load transmitted from the mooring line (31) connected to the steel cap (35). The longer the height (h2) of the steel cap (35), the more evenly the load can be transmitted to the outer column (130) formed of concrete connected thereto.

[0107] Accordingly, the height (h2) of the steel cap (35) can preferably be set between 1 / 20 and 1 / 2 of the height (h1) of the outer column (130), taking into account the size of the configuration connected to the steel cap (35) and the size of the load being transmitted.

[0108] The brace (160) can be provided to be connected to the steel cap (35).

[0109] The floating structure (200) can distribute the load concentrated on the steel section (129) by connecting a brace (160) to the steel cap (35). That is, the load of the center column (110) transmitted from the connecting member (140) can be concentratedly transmitted to the steel section (129), and the load of the center column (110) transmitted from the brace (160) and the external force transmitted through the mooring line (31) can be transmitted to the steel cap (35).

[0110] Although the technical concept of the present invention has been explained above through specific embodiments, the scope of the present invention is not limited to these embodiments. Various embodiments that can be modified or varied by those skilled in the art within the scope that does not deviate from the gist of the technical concept of the present invention as specified in the claims shall also be considered to fall within the scope of the present invention.

Claims

1. A center column to which a tower including an offshore wind turbine nacelle is connected; A pontoon comprising multiple sides and connected to the center column; An outer column positioned between multiple sides of the above-mentioned pontoon; A connecting member connecting the above pontoon and the above center column; including, The above pontoon includes a concrete section connected to the outer column on the plurality of sides and forming both ends of the plurality of sides, and a steel section disposed between the concrete sections disposed at both ends of the plurality of sides and connecting the concrete sections disposed at both ends of the plurality of sides. The above connecting member is combined with the above steel member to form a floating structure that allows the pontoon to be connected to the center column.

2. In Paragraph 1, It further includes an anchor provided to be fixed to the seabed, and a mooring line connecting the anchor and the floating structure. The above mooring line is a floating structure arranged to be connected to the above steel section.

3. In Paragraph 1, The plurality of sides of the above pontoon include three sides, and The above concrete section includes a first concrete section, a second concrete section, and a third concrete section formed between the three sides, respectively. A floating structure in which the first concrete section, the second concrete section, and the third concrete section are provided with the same shape.

4. In Paragraph 3, A floating structure in which the first concrete section, the second concrete section, and the third concrete section are each symmetrically arranged around the center column.

5. In Paragraph 3, A floating structure in which the first concrete part, the second concrete part, and the third concrete part are each arranged to be interchangeably combined with the steel part.

6. In Paragraph 1, A floating structure in which the length of the steel member in the extension direction of each of the plurality of sides is provided to be 1 / 20 to 9 / 10 relative to the length of each of the respective sides.

7. In Paragraph 1, The above pontoon further includes a brace provided to additionally support the center column, and The above brace is a floating structure formed to be combined with the above steel section and extended to the above center column.

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