Floating wind turbine foundation, offshore wind power system and installation method of offshore wind power system

Abstract

The present invention relates to the technical field of floating wind turbine foundations, and specifically to a floating wind turbine foundation, an offshore wind power system and an installation method for an offshore wind power system. The floating wind turbine foundation includes a top structure, a ballast tank, a cable structure and a column. The top of the top structure is suitable for connecting with a wind turbine tower. The interior of the ballast tank is provided with a filling cavity suitable for filling ballast, and the ballast tank is arranged at the bottom of the top structure. One end of the cable structure is connected to the periphery of the ballast tank, and the other end is connected to the periphery of the top structure. The bottom end of the column is fixedly connected to the top center of the ballast tank. The top structure is sleeved on the periphery of the column, and has an installation state of being detachably fixedly connected to the top of the column, and a towing state of being placed on the top of the ballast tank. The floating wind turbine foundation can jointly resist the external loads such as wind, waves, and currents, as well as the loads transmitted from the upper wind turbine. The overall structure is relatively simple, and the assembly and connection are relatively simple and convenient.

Description

Technical Field

[0001] The present invention relates to the technical field of offshore wind turbines, and in particular to a floating wind turbine foundation, an offshore wind power system and an installation method of the offshore wind power system. Background Art

[0002] As a renewable energy source, offshore wind power has entered a large-scale development stage. Conventional offshore wind turbine foundations are often fixed on the seabed using fixed offshore wind turbine foundations. When used in deep sea, fixed offshore wind turbine foundations are usually bulky and difficult to tow and install. Summary of the invention

[0003] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the fixed offshore wind turbine foundation in the prior art that is relatively bulky and difficult to tow and install, thereby providing a floating wind turbine foundation, an offshore wind power system and an installation method of an offshore wind power system with a simple structure and less difficulty in tow and installation.

[0004] In order to solve the above technical problems, the present invention provides a floating wind turbine foundation, comprising a top structure, the top of which is suitable for connecting with a wind turbine tower;

[0005] A ballast tank, which has a filling cavity suitable for filling ballast, and the ballast tank is arranged at the bottom of the top structure;

[0006] a cable structure, one end of which is connected to the outer periphery of the ballast tank and the other end of which is connected to the outer periphery of the top structure;

[0007] The bottom end of the column is fixedly connected to the top center of the ballast tank; the top structure is sleeved on the outer periphery of the column and has an installation state in which it is detachably fixedly connected to the top of the column, and a towing state in which it is placed on the top of the ballast tank.

[0008] In the floating wind turbine foundation provided by the present invention, at least two partitions are provided inside the ballast tank, and at least two of the partitions divide the filling cavity into at least four compartments distributed along the circumferential direction;

[0009] Alternatively, the ballast tank comprises at least four tank bodies which are fixedly connected in sequence along the circumferential direction, and each of the tank bodies is provided with the filling cavity.

[0010] In the floating wind turbine foundation provided by the present invention, the partition is integrally formed inside the ballast tank; or at least four tanks are welded in sequence along the circumferential direction;

[0011] And / or, at least two of the partitions evenly divide the filling cavity into at least four partition compartments; or, the volumes of the filling cavities in each of the boxes are equal.

[0012] And / or, the ballast tank is a cylindrical structure.

[0013] In the floating wind turbine foundation provided by the present invention, the bottom end of the column is welded to the top center of the ballast tank.

[0014] The floating wind turbine foundation provided by the present invention, the top structure comprises:

[0015] A base ring is slidably sleeved on the outer periphery of the column and has the installation state of being detachably fixedly connected to the top end of the column;

[0016] A buoyancy box is sleeved on the outer circumference of the base ring and connected to the bottom end of the base ring;

[0017] A crossbeam structure has one end connected to the buoyancy box and the other end connected to the top end of the base ring.

[0018] The floating wind turbine foundation provided by the present invention comprises at least three beams distributed along the circumference of the foundation ring, one end of each beam is connected to the outer periphery of the buoyancy box, and the other end is connected to the top of the foundation ring.

[0019] In the floating wind turbine foundation provided by the present invention, the foundation ring and the column are detachably connected via a plurality of groups of fasteners, and the plurality of groups of fasteners are distributed along the circumference of the column.

[0020] The floating wind turbine foundation provided by the present invention, the cable structure comprises at least three flexible cable ropes distributed along the circumference of the ballast tank.

[0021] The present invention also provides an offshore wind power system, comprising:

[0022] The above-mentioned floating wind turbine foundation;

[0023] A wind turbine, comprising a wind turbine tower and a wind turbine body connected to the top of the wind turbine tower, wherein the bottom end of the wind turbine tower is connected to the floating wind turbine foundation;

[0024] An anchoring system is connected to the floating wind turbine foundation.

[0025] The present invention also provides an offshore wind power system installation method, which is used for installing the above offshore wind power system, and comprises the following steps:

[0026] Installing the floating wind turbine foundation to a towing state;

[0027] Towing the floating wind turbine foundation in a towing state to a predetermined position by a tugboat;

[0028] Deployment of mooring systems;

[0029] Installing the floating wind turbine foundation to an installed state;

[0030] Install the fan.

[0031] The technical solution of the present invention has the following advantages:

[0032] The floating wind turbine foundation provided by the present invention includes a top structure, a ballast tank, a cable structure and a column. The top structure is sleeved on the outer periphery of the column, and the top structure and the ballast tank are connected by a cable structure. The cable structure and the column provide tension and pressure respectively. The top structure and the ballast tank are connected into a force-bearing whole to jointly resist the external loads such as wind, waves, and currents and the loads transmitted from the upper wind turbine. The overall floating wind turbine foundation structure is relatively simple, and the assembly and connection are relatively simple and convenient. The floating wind turbine foundation provides buoyancy support for the upper wind turbine, and at the same time, the restoring moment generated between the overall gravity and the buoyancy generated by the ballast float when the structure is tilted is used to maintain the balance of the entire structure. Moreover, the ballast tank can be installed without water or other ballast during towing. The buoyancy provided by the filling cavity in the ballast tank can be used to float the entire floating wind turbine foundation. The water depth is shallow, which can significantly reduce the water resistance of towing. Moreover, since the top structure is sleeved on the outer periphery of the column when in the towing state and placed on the top of the ballast tank, the top structure is relatively fixed on the ballast tank and will not fall off during towing. After towing in place, the top structure can be fixedly connected to the top of the column to achieve the installation state, and then water is filled into the filling cavity of the ballast tank, so that the center of gravity of the entire floating wind turbine foundation moves downward, and the center of gravity is located below the buoyancy center, providing an anti-tilting moment for the wind turbine. After installation, the top structure floats above the water surface as a whole or in large part, providing a greater anti-tilting moment. The column is fixedly connected to the top center of the ballast tank, which plays a vertical support role, and can be fixedly connected to the top structure during towing and after installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A front view of the floating wind turbine foundation provided by the present invention;

[0035] Figure 2 A top view of the floating wind turbine foundation provided by the present invention;

[0036] Figure 3 for Figure 2 A magnified view of part A;

[0037] Figure 4 A schematic diagram of the offshore wind power system provided by the present invention in a towing state;

[0038] Figure 5 for Figure 4 A magnified view of part B;

[0039] Figure 6 A schematic diagram of an offshore wind power system provided by the present invention in an installed state;

[0040] Figure 7 A schematic diagram of an offshore wind power system after installation provided by the present invention;

[0041] Figure 8 A schematic diagram of the installation steps of the offshore wind power system provided by the present invention.

[0042] Description of reference numerals:

[0043] 1. Top structure; 11. pontoon; 12. foundation ring; 13. beam; 2. ballast tank; 3. cable structure; 4. column; 5. fasteners; 6. wind turbine tower; 7. wind turbine body; 8. anchoring system; 9. tugboat; 10. sea surface. DETAILED DESCRIPTION

[0044] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0046] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0048] like Figures 1 to 8 As shown, the present embodiment discloses a floating wind turbine foundation, comprising a top structure 1, a ballast tank 2, a cable structure 3 and a column 4, wherein the top end of the top structure 1 is suitable for being connected to a wind turbine tower 6; a filling cavity suitable for filling ballast is provided inside the ballast tank 2, and the ballast tank 2 is arranged at the bottom of the top structure 1; one end of the cable structure 3 is connected to the outer periphery of the ballast tank 2, and the other end is connected to the outer periphery of the top structure 1; the bottom end of the column 4 is fixedly connected to the top center of the ballast tank 2; the top structure 1 is sleeved on the outer periphery of the column 4, and has an installation state in which it is detachably fixedly connected to the top end of the column 4, and a towing state in which it is placed on the top of the ballast tank 2.

[0049] The floating wind turbine foundation provided in this embodiment includes a top structure 1, a ballast tank 2, a cable structure 3 and a column 4. The top structure 1 is sleeved on the outer periphery of the column 4, and the top structure 1 is connected to the ballast tank 2 through the cable structure 3. The cable structure 3 and the column 4 provide tension and pressure respectively, and the top structure 1 and the ballast tank 2 are connected into a force-bearing whole to jointly resist the external loads such as wind, waves, and currents and the loads transmitted from the upper wind turbine. The overall floating wind turbine foundation structure is relatively simple, and the assembly and connection are relatively simple and convenient. The floating wind turbine foundation provides buoyancy support for the upper wind turbine, and at the same time, the restoring moment generated between the overall gravity and the buoyancy generated by the ballast float when the structure is tilted is used to maintain the balance of the entire structure. Moreover, the ballast tank 2 may not be filled with water or other ballast during towing installation. The buoyancy provided by the filling cavity in the ballast tank 2 can be used to float the entire floating wind turbine foundation. The water depth is shallow, which can significantly reduce the water resistance of towing. Moreover, since the top structure 1 is sleeved on the outer periphery of the column 4 when in the towing state and is placed on the top of the ballast tank 2, the top structure 1 is relatively fixed on the ballast tank 2 and will not fall off during towing. After towing in place, water is first filled into the filling cavity of the ballast tank 2 to move the center of gravity of the entire floating wind turbine foundation downward, and the center of gravity is located below the buoyancy center. Then, the top structure 1 is fixedly connected to the top of the column 4 to achieve the installation state, and jointly provide an anti-tilting moment for the wind turbine. After installation, the top structure 1 floats above the water surface as a whole or in large part, providing a greater anti-tilting moment. The column 4 is fixedly connected to the top center of the ballast tank 2 to play a vertical support role, and can be fixedly connected to the top structure 1 during towing and after installation.

[0050] In a specific implementation of this embodiment, at least two partitions are provided inside the ballast tank 2, and at least two of the partitions divide the filling cavity into at least four compartments distributed along the circumferential direction. The compartments are not connected to each other. In the towing state, the buoyancy provided by each compartment floats the entire floating wind turbine foundation, and the water depth is shallow, which can significantly reduce the towing water resistance. In the installation state, the top structure 1 is connected to the top of the column 4, and after the cable structure 3 is tightened, water and other ballast are filled into each compartment. The ballast tank 2 sinks into the water to a certain depth, so that the center of gravity of the entire structure moves downward, and the center of gravity is located below the buoyancy center, providing an anti-tilting moment for the wind turbine. When tilted by the upper load of the floating wind turbine foundation, since the compartments are not connected to each other, it is beneficial for the floating wind turbine foundation to reset under the action of gravity. Each compartment includes a liquid inlet, and a sealing cover is sealed and connected at the liquid inlet, or a sealing cover is sealed and welded at the liquid inlet. At least two partitions are arranged crosswise, and the intersection is located at the center of the ballast tank.

[0051] Furthermore, the partition is integrally formed inside the ballast tank 2, and has a simple structure and is easy to form.

[0052] Furthermore, at least two of the partitions evenly divide the filling cavity into at least four compartments, so that each compartment is evenly stressed.

[0053] Furthermore, the ballast tank 2 is a cylindrical structure, and the outer periphery is subjected to force more evenly and smoothly. The ballast tank 2 can be a disc-shaped structure with a lower height and greater buoyancy. As a convertible embodiment, the ballast tank 2 can also be a multi-deformable structure with a top surface of a triangle, rectangle, pentagon, hexagon, etc.

[0054] In another specific implementation of this embodiment, the ballast tank 2 includes at least four boxes that are fixedly connected in sequence along the circumferential direction, and each box is provided with the filling cavity. The boxes are not connected to each other. In the towing state, the buoyancy provided by each box floats the entire floating wind turbine foundation, and the water depth is shallow, which can significantly reduce the towing water resistance. In the installation state, the top structure 1 is connected to the top of the column 4, and after the cable structure 3 is tightened, water and other ballast are filled into each box. The ballast tank 2 sinks into the water to a certain depth, so that the center of gravity of the entire structure moves downward, and the center of gravity is located below the buoyancy center, providing an anti-tilting moment for the wind turbine. When the floating wind turbine foundation is tilted by the upper load, since the boxes are not connected to each other, it is beneficial for the floating wind turbine foundation to reset under the action of gravity. Each box includes a liquid inlet, and a sealing cover is sealed and connected to the liquid inlet, or a sealing cover is sealed and welded to the liquid inlet.

[0055] Furthermore, at least four boxes are welded in sequence along the circumference, and the connection is relatively stable. Alternatively, at least four boxes are fixedly connected in sequence along the circumference by threaded structures such as bolts and screws.

[0056] Furthermore, the volume of the filling cavity in each box body is equal, so that the structure is symmetrical and the force is evenly distributed.

[0057] In this embodiment, the bottom end of the column 4 is welded to the center of the top of the ballast tank 2, and the connection is stable. The axial direction of the column 4 is vertically welded to the top of the ballast tank 2. As a convertible embodiment, the top of the ballast tank 2 may be protrudingly connected with a plurality of lugs, and the bottom end of the column 4 is detachably connected to the lugs through a fastener 5.

[0058] In this embodiment, the top structure 1 includes a buoyancy box 11, a base ring 12 and a crossbeam 13 structure. The base ring 12 is slidably mounted on the outer periphery of the column 4 and has the installation state of being detachably fixedly connected to the top end of the column 4; the buoyancy box 11 is mounted on the outer periphery of the base ring 12 and is connected to the bottom end of the base ring 12; one end of the crossbeam 13 structure is connected to the buoyancy box 11, and the other end is connected to the top end of the base ring 12.

[0059] The outer periphery of the pontoon 11 is fixedly connected to the top of the base ring 12 through the crossbeam 13 structure, and the inner periphery of the pontoon 11 is connected to the base ring 12. The inner periphery of the pontoon 11 can be welded to the base ring 12. The pontoon 11, the crossbeam 13 structure and the base ring 12 are connected to form a triangular cross-section structure, and the connection is stable. And the top structure 1 is more convenient to be detachably connected to the column 4 through the base ring 12. Through the arrangement of the base ring 12 and the crossbeam 13 structure, the stability of the connection between the pontoon 11 and the column 4 is enhanced, and the overall strength of the top structure 1 is also enhanced. And because the base ring 12 is slidably sleeved on the outer periphery of the column 4, the base ring 12 is detachably fixedly connected to the top of the column 4, so that the top structure 1 can be placed on the top of the ballast tank 2 in the towing state, and is detachably fixedly connected to the top of the column 4 in the installation state. Specifically, the pontoon 11 is annular and is sleeved on the outer periphery of the base ring 12 through an inner ring.

[0060] As a convertible embodiment, the top structure 1 may include an annular buoyancy box 11 and lugs connected to the buoyancy box 11, and the buoyancy box 11 is detachably fixedly connected to the base ring 12 via the lugs.

[0061] In this embodiment, the crossbeam 13 structure includes at least three crossbeams 13 distributed along the circumference of the base ring 12, one end of each of the crossbeams 13 is connected to the outer periphery of the pontoon 11, and the other end is connected to the top of the base ring 12. The crossbeam 13 structure can realize a fixed connection between the top of the base ring 12 and the pontoon 11 in the circumferential direction, and the crossbeam 13 can be a rigid structure made of metal such as steel and alloy to realize a rigid connection between the pontoon 11 and the base ring 12. As a convertible embodiment, one end of the crossbeam 13 can be connected to the middle position of the pontoon 11, and the other end is connected to the base ring 12, or one end of the crossbeam 13 can be connected to a circular ring between the inner ring and the outer ring of the pontoon 11, and the other end is connected to the base ring 12.

[0062] Furthermore, the projection area of ​​the cross beam 13 on the pontoon 11 gradually decreases from the outer circumference to the inner circumference of the pontoon 11. The connection length between the pontoon 11 and the pontoon 11 with a larger diameter can be increased.

[0063] In this embodiment, the base ring 12 and the column 4 are detachably connected via a plurality of groups of fasteners 5 , and the plurality of groups of fasteners 5 are distributed along the circumference of the column 4 .

[0064] In this embodiment, the cable structure 3 includes at least three flexible cables distributed along the circumference of the ballast tank 2. In the towing state, the flexible cables are bent so that the buoyancy tank 11 can be placed on the ballast tank 2. In the installation state, the flexible cables are tightened to provide tension. The flexible cables can be made of high-strength anti-corrosion materials, the flexible cables can be anchor chains, or the flexible cables are made of carbon fiber materials.

[0065] This embodiment also provides an offshore wind power system, including the above-mentioned floating wind turbine foundation, a wind turbine and an anchoring system 8, the wind turbine including a wind turbine tower 6 and a wind turbine body 7 connected to the top of the wind turbine tower 6, the bottom end of the wind turbine tower 6 is connected to the floating wind turbine foundation; the anchoring system 8 is connected to the floating wind turbine foundation.

[0066] This embodiment also provides an offshore wind power system installation method, which is used for installing the above offshore wind power system, and includes the following steps:

[0067] Installing the floating wind turbine foundation to a towing state;

[0068] Towing the floating wind turbine foundation in a towing state to a predetermined position by a tugboat 9;

[0069] Deployment of mooring system8;

[0070] Installing the floating wind turbine foundation to an installed state;

[0071] Install the fan.

[0072] Among them, the step of installing the floating wind turbine foundation to the towing state includes: connecting the column 4 to the ballast tank 2, sleeve the top structure 1 on the column 4, and connecting the ballast tank 2 and the top structure 1 through the cable structure 3; the cable structure 3 is bent and placed on the ballast tank 2.

[0073] Among them, installing the floating wind turbine foundation to the installation state includes: filling water into the ballast tank 2, the ballast tank 2 sinks a certain distance from the sea surface 10 into the water, the top structure 1 floats on the sea surface 10 due to the existence of the pontoon 11, and after the ballast tank 2 drops a certain distance, the top structure 1 is fixedly connected to the top of the column 4, and the cable structure 3 is pre-tightened.

[0074] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A floating wind turbine foundation, characterized in that: include: A top structure (1), the top end of which is suitable for connection with a wind turbine tower (6); A ballast tank (2) having a filling cavity suitable for filling ballast, and the ballast tank (2) is arranged at the bottom of the top structure (1); A cable structure (3), one end of which is connected to the outer periphery of the ballast tank (2), and the other end of which is connected to the outer periphery of the top structure (1); The bottom end of the column (4) is fixedly connected to the top center of the ballast tank (2); the top structure (1) is sleeved on the outer periphery of the column (4) and has an installation state in which it is detachably fixedly connected to the top of the column (4), and a towing state in which it is placed on the top of the ballast tank (2); The top structure (1) comprises: A base ring (12) is slidably sleeved on the outer periphery of the column (4) and has the installation state of being detachably fixedly connected to the top end of the column (4); A buoyancy box (11) is sleeved on the outer circumference of the base ring (12) and connected to the bottom end of the base ring (12); A crossbeam (13) structure has one end connected to the buoyancy box (11) and the other end connected to the top end of the base ring (12).

2. The floating wind turbine foundation according to claim 1, characterized in that: The ballast tank (2) is provided with at least two partitions inside, and the at least two partitions divide the filling cavity into at least four partition compartments distributed along the circumferential direction; Alternatively, the ballast tank (2) comprises at least four tank bodies which are fixedly connected in sequence along the circumferential direction, and each of the tank bodies is provided with the filling cavity.

3. The floating wind turbine foundation according to claim 2, characterized in that: The partition is integrally formed inside the ballast tank (2); or at least four tanks are welded in sequence along the circumferential direction; And / or, at least two of the partitions evenly divide the filling cavity into at least four partition compartments; or, the volumes of the filling cavities in each of the boxes are equal; And / or, the ballast tank (2) is a cylindrical structure.

4. The floating wind turbine foundation according to claim 1, characterized in that: The bottom end of the column (4) is welded to the top center of the ballast tank (2).

5. The floating wind turbine foundation according to claim 1, characterized in that: The crossbeam (13) structure comprises at least three crossbeams (13) distributed along the circumference of the base ring (12), one end of each crossbeam (13) is connected to the outer periphery of the buoyancy box (11), and the other end is connected to the top end of the base ring (12).

6. The floating wind turbine foundation according to claim 1, characterized in that: The base ring (12) and the column (4) are detachably connected via a plurality of sets of fasteners (5), and the plurality of sets of fasteners (5) are distributed along the circumference of the column (4).

7. The floating wind turbine foundation according to any one of claims 1 to 6, characterized in that: The cable structure (3) comprises at least three flexible cable ropes distributed along the circumference of the ballast tank (2).

8. An offshore wind power system, characterized in that: include: The floating wind turbine foundation according to any one of claims 1 to 7; A wind turbine, comprising a wind turbine tower (6) and a wind turbine body (7) connected to the top of the wind turbine tower (6), wherein the bottom end of the wind turbine tower (6) is connected to the floating wind turbine foundation; An anchoring system (8) is connected to the floating wind turbine foundation.

9. A method for installing an offshore wind power system, characterized in that: The installation of the offshore wind power system according to claim 8 comprises the following steps: Installing the floating wind turbine foundation to a towing state; Towing the floating wind turbine foundation in a towing state to a predetermined position by a tugboat (9); Deployment of mooring systems (8); Installing the floating wind turbine foundation to an installed state; Install the fan.

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