Floating type offshore wind turbine foundation capable of self-adapting to tide level and convenient to install

Abstract

The utility model discloses a floating type offshore wind turbine foundation capable of self-adapting to the tide level and convenient to install, which belongs to the technical field of offshore wind power generation and comprises an anchoring cylinder located at the bottom of the whole foundation, and the anchoring cylinder is connected with a main buoy through a central thin column and a mooring line. The two ends of the center thin column are connected with the top face center of the anchoring barrel and the bottom face center of the main buoy respectively, one end of the mooring line is connected with the top face edge of the main buoy, the other end of the mooring line is connected to the junction of the anchoring barrel and the center thin column, the damping buoyancy tanks are arranged around the side face of the main buoy at intervals, and the center stand column is arranged at the top face center of the main buoy. The problems that tension of tension tendons of an existing TLP type wind turbine foundation is greatly affected by damp positions, waves and ocean currents, resonance motion is prone to occurring due to frequency coupling of an upper structure and a mooring system, and consequently the structure is unsafe are solved, the service life of the wind turbine foundation is prolonged, meanwhile, the special structure with the holes can remarkably reduce the wave height, the wave load is reduced, and the service life of the wind turbine foundation is prolonged. And the foundation stability is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of offshore wind power generation, and particularly relates to a floating offshore wind turbine foundation which can adapt to the tide level and is convenient to install. Background Art

[0002] With the continuous consumption of oil, people are forced to seek cleaner and renewable energy to meet the energy demand. Offshore wind power is a continuously renewable and infinite energy source, and has currently become an important direction for alleviating the global energy crisis and environmental problems. With the exhaustion of the development of offshore wind energy resources in near-shallow waters, the development of offshore wind power towards the deep sea has become an inevitable trend. Considering that the action intensities of various loads such as wind, wave, and current in the deep-sea environment are much greater than those in the near sea, the construction and installation costs of traditional offshore fixed wind turbine foundations will be extremely high. The floating foundation supports the upper wind turbine unit to float on the sea surface through buoyancy, which can greatly reduce the construction and installation costs of deep-sea wind turbine foundations and is an effective solution to solve the deep-water problem.

[0003] Currently, offshore wind power floating foundations mainly include three types, namely: semi-submersible, Spar, and TLP floating foundations. The main body of the semi-submersible foundation consists of multiple columns and pontoons, and is positioned through a mooring system. The column spacing is relatively large, resulting in a relatively large restoring moment, which is beneficial to improving the structural stability. However, the pontoons of the semi-submersible foundation located below the waterline have a relatively large scale and will be subjected to greater wave loads, resulting in an increase in the longitudinal motion amplitude. Usually, a relatively large and heavy floating body structure is required, or a dynamic stability system is equipped to maintain stability. The main body of the Spar foundation is a steel cylinder with a bottom ballast, and is connected to the seabed pile foundation through a radial mooring system. Due to the ballast weight at the bottom of the structure, its center of gravity is below the center of buoyancy, and the stability is better. However, the small waterplane area of the Spar foundation results in relatively large pitching and rolling motion amplitudes, which may have a certain impact on the power generation performance of the upper wind turbine. The Spar foundation can usually only be deployed in areas with a water depth exceeding 100 m, and its transportation and installation challenges are relatively large. The TLP floating foundation consists of a semi-submersible structure, plus tensioned ropes and anchor ropes fixed to the seabed. Its floating body structure is smaller and lighter than that of the semi-submersible platform, and its stability is mainly maintained by the tightened anchor chains. The advantage of this design is that the cost of the floating body structure is low, but it increases the stress of the anchoring system, resulting in an increased probability of damage, and its installation process is also more complex.

[0004] Compared with other floating foundations, limited platform motion is expected to reduce the structural loads on the tower and blades. Especially for sites where the catenary mooring system is not applicable, the TLP floating wind turbine has a better application prospect. However, the tension mooring system of the existing TLP wind turbine foundation is complex, the construction and installation difficulty and the demolition cost are high, and the tendon tension is greatly affected by the tide level, waves, and ocean currents. The frequency coupling of the upper structure and the mooring system is prone to resonance motion, which is not conducive to structural safety. Summary of the Utility Model

[0005] The purpose of the present utility model is to address the problems of the existing TLP type wind turbine foundation where the tension of the tendon is greatly affected by the tide level, waves, and ocean currents, and the frequency coupling between the upper structure and the mooring system is prone to resonance motion, leading to structural insecurity.

[0006] To solve the above technical problems, the present utility model provides a floating offshore wind turbine foundation that can adapt to the tide level and is convenient to install, including: a floating body platform, a central slender column, a mooring line, and an anchoring cylinder; the floating body platform provides the buoyancy required to carry the upper wind turbine unit and serves as a connection between the upper and lower structures, including a central column, a main floating cylinder, and several damping floating boxes; the anchoring cylinder is located at the bottom of the entire foundation, and the anchoring cylinder is connected to the main floating cylinder through the central slender column and the mooring line. The two ends of the central slender column are respectively connected to the center of the top surface of the anchoring cylinder and the center of the bottom surface of the main floating cylinder. One end of the mooring line is connected to the edge of the top surface of the main floating cylinder, and the other end is connected to the junction of the anchoring cylinder and the central slender column. The damping floating boxes are arranged at intervals around the side of the main floating cylinder, and a central column is provided at the center of the top surface of the main floating cylinder.

[0007] Preferably, the central column is located at the topmost end of the floating body platform, and a flange is provided at its top and connected to the bottom of the wind turbine unit.

[0008] Preferably, the main floating cylinder mainly provides buoyancy. It is circular ring-shaped, located at the center of the floating body platform, connected to the central column at the top, and a mooring line tensioning device is arranged at the intersection of the main floating cylinder and the mooring line.

[0009] Preferably, the central slender column extends into the internal cavity of the main floating cylinder and maintains a certain interval, and can perform telescopic movement in the vertical direction as the tide level changes.

[0010] Preferably, multiple damping holes are arranged on the damping floating box, and its main function is to reduce the impact of waves on the floating body platform and use the hollow part to assist in providing buoyancy.

[0011] Preferably, the central slender column is a slender steel pipe pile, its lower end is connected to the anchoring cylinder, and its upper end extends into the internal cavity of the main floating cylinder and restricts the horizontal displacement of the main floating cylinder.

[0012] Preferably, the anchoring cylinder adopts a steel suction cylinder and can be inserted into the seabed by a negative pressure installation method.

[0013] Advantages of the present utility model:

[0014] 1. In this solution, the main floating barrel is set in a toroidal shape, and the central thin column extends into the ring, which limits the horizontal displacement of the floating platform while enabling it to move vertically with the change of the tide level, avoiding the influence of the tide level change on the mooring line tension, improving the service life of the mooring line, and further enhancing the service life of the wind turbine foundation.

[0015] 2. In this solution, by using the suction bucket penetrating into the seabed as the anchoring device, the foundation construction and installation are convenient, and it has the advantages of being quickly removable and reusable.

[0016] 3. This solution arranges three open - hole cuboid damping floating boxes around the main floating barrel. The special structure of the open holes can significantly reduce the wave height, reduce the wave load, and improve the stability of the foundation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By reading the detailed description of the non - restrictive embodiments with reference to the following drawings, other features, purposes, and advantages of the present utility model will become more obvious. The drawings are only for the purpose of showing the preferred embodiments and are not considered as a limitation to the present utility model. Moreover, throughout the drawings, the same reference signs are used to represent the same components.

[0018] Figure 1 is the three - dimensional structure diagram of the present utility model;

[0019] Figure 2 is the front view of the present utility model;

[0020] Figure 3 is the left view of the present utility model;

[0021] Figure 4 is the top view of the present utility model;

[0022] Figure 5 is the internal structure schematic diagram of the present utility model.

[0023] In the drawings, the list of components represented by each reference number is as follows:

[0024] 1. Central column; 2. Main floating barrel; 3. Damping floating box; 4. Mooring line; 5. Anchoring barrel; 6. Central thin column; 7. Mooring line tensioning device; 8. Damping hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] To make the objectives, technical solutions and advantages of the present utility model clearer and more understandable, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific implementation manners described herein are only the best embodiments of the present utility model, which are only used to explain the present utility model and do not limit the protection scope of the present utility model. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present utility model.

[0026] Embodiment 1: As Figure 1 shown, a floating offshore wind turbine foundation that can adapt to the tide level and is convenient to install includes: a floating body platform, a central thin column 6, a mooring line 4 and an anchoring cylinder 5; the floating body platform includes a central column 1, a main floating cylinder 2 and a number of damping floating boxes 3; the anchoring cylinder 5 is located at the bottom of the entire foundation, and the anchoring cylinder 5 is connected to the main floating cylinder 2 through the central thin column 6 and the mooring line 4. The two ends of the central thin column 6 are respectively connected to the center of the top surface of the anchoring cylinder 5 and the center of the bottom surface of the main floating cylinder 2. One end of the mooring line 4 is connected to the edge of the top surface of the main floating cylinder 2, and the other end is connected to the junction of the anchoring cylinder 5 and the central thin column 6. The damping floating boxes 3 are arranged at intervals around the side of the main floating cylinder 2, and a central column 1 is provided at the center of the top surface of the main floating cylinder 2.

[0027] Specifically, a flange is provided at the top of the central column 1 and is connected to the bottom of the wind turbine unit.

[0028] Specifically, a mooring line tensioning device 7 is arranged at the intersection of the main floating cylinder 2 and the mooring line 4.

[0029] Specifically, the connection end of the central thin column 6 with the main floating cylinder 2 extends into the cavity in the main floating cylinder 2 that matches the central thin column 6 and keeps a certain interval from the top end of the cavity.

[0030] Specifically, a number of damping holes 8 are provided through the damping floating box 3.

[0031] In this embodiment, by setting the main floating cylinder in a circular ring shape and keeping a certain distance between the central thin column and the top end of the cavity, the horizontal displacement of the floating body platform is restricted while enabling it to move vertically with the change of the tide level, avoiding the influence of the tide level change on the tension of the mooring line and improving the service life of the mooring line.

[0032] Embodiment 2: As Figures 1 - 4As shown in the figure, a floating offshore wind turbine foundation that can adapt to the tide level and is convenient to install includes: a floating body platform, a central slender column 6, a mooring line 4, and an anchoring cylinder 5; the floating body platform provides the buoyancy required to carry the upper wind turbine unit and plays a role in connecting the upper and lower structures, including a central column 1, a main floating cylinder 2, and three damping floating boxes 3; the anchoring cylinder 5 is located at the bottom of the entire foundation, and the anchoring cylinder 5 is connected to the main floating cylinder 2 through the central slender column 6 and the mooring line 4. The two ends of the central slender column 6 are respectively connected to the center of the top surface of the anchoring cylinder 5 and the center of the bottom surface of the main floating cylinder 2. One end of the mooring line 4 is connected to the edge of the top surface of the main floating cylinder 2, and the other end is connected to the junction of the anchoring cylinder 5 and the central slender column 6. The damping floating boxes 3 are arranged at intervals around the side of the main floating cylinder 2, and a central column 1 is provided at the center of the top surface of the main floating cylinder 2.

[0033] Specifically, the central column 1 is located at the topmost end of the floating body platform, and a flange is provided at its top and is connected to the bottom of the wind turbine unit.

[0034] Specifically, the main floating cylinder 2 mainly provides buoyancy. It is circular ring-shaped, located at the center of the floating body platform, the top is connected to the central column 1, and a mooring line tensioning device 7 is arranged at the intersection of the main floating cylinder 2 and the mooring line 4.

[0035] Specifically, as Figure 5 shown in the figure, the central slender column 6 extends into the internal cavity of the main floating cylinder 2 and maintains a certain interval, and can perform telescopic movement in the vertical direction as the tide level changes.

[0036] Specifically, the damping floating box 3 is a flat cuboid as a whole, and a plurality of damping holes 8 are arranged on it. Its main function is to reduce the impact of waves on the floating body platform and use the hollow part to assist in providing buoyancy. The three damping floating boxes 3 are arranged around the main floating cylinder 2 in an equilateral triangle.

[0037] In this embodiment, three cuboid damping floating boxes 3 with openings are arranged around the main floating cylinder 2. The special structure of the openings can significantly reduce the wave height of the waves, reduce the wave load, and improve the stability of the foundation.

[0038] Specifically, the central slender column 6 is a slender steel pipe pile, its lower end is connected to the anchoring cylinder 5, and its upper end extends into the internal cavity of the main floating cylinder 2 and restricts the horizontal displacement of the main floating cylinder 2.

[0039] Specifically, there are three groups of mooring lines 4, which are connected to the main floating cylinder 2 and the anchoring cylinder 5 in an equilateral triangle distribution.

[0040] Specifically, the anchoring cylinder 5 is a steel suction cylinder and can be inserted into the seabed by means of negative pressure installation.

[0041] In this embodiment, the suction cylinder is penetrated into the seabed as an anchoring device, making the foundation construction and installation convenient, and having the advantages of being quickly removable and reusable.

[0042] When the sea surface fluctuates, since the mooring cylinder 5 is fixedly connected to the central thin column 6 and is in a "convex" shape, and there is a cavity at the center where the main floating cylinder 2 contacts the central thin column 6, it can move up and down within the main floating cylinder 2 as the tide level changes. At the same time, because one end of the mooring line 4 is connected to the top edge of the main floating cylinder 2 and the other end is connected to the junction of the mooring cylinder 5 and the central thin column 6, the horizontal displacement of the upper floating body platform is restricted, avoiding the influence of tide level changes on the tension of the mooring line 4 and improving the service life of the mooring line 4.

[0043] The above specific implementation manners are the preferred implementation manners of the present utility model, and do not limit the specific implementation scope of the present utility model. The scope of the present utility model includes but is not limited to this specific implementation manner. Any equivalent changes made according to the shape, structure, and method of the present utility model are within the protection scope of the present utility model.

Claims

1. A floating offshore wind turbine foundation that is adaptive to tide levels and easy to install, characterized in that: The invention comprises a floating platform, a central thin column (6), a mooring line (4) and an anchoring cylinder (5); the floating platform comprises a central column (1), a main buoy (2) and a plurality of damping buoys (3); the anchoring cylinder (5) is located at the bottom of the entire foundation, the anchoring cylinder (5) and the main buoy (2) are connected via the central thin column (6) and the mooring line (4), the two ends of the central thin column (6) are respectively connected to the top surface center of the anchoring cylinder (5) and the bottom surface center of the main buoy (2), one end of the mooring line (4) is connected to the top surface edge of the main buoy (2), and the other end is connected to the junction of the anchoring cylinder (5) and the central thin column (6), the damping buoys (3) are arranged at intervals around the side of the main buoy (2), and a central column (1) is provided at the top surface center of the main buoy (2).

2. The floating offshore wind turbine foundation that can adapt to tide level and is easy to install according to claim 1 is characterized by: A flange is arranged on the top of the central column (1) and is connected to the bottom of the wind turbine generator set.

3. The floating offshore wind turbine foundation that can adapt to tide level and is easy to install according to claim 1 is characterized by: A mooring line tensioning device (7) is arranged at the intersection of the main buoy (2) and the mooring line (4).

4. The floating offshore wind turbine foundation that can adapt to tide level and is easy to install according to claim 1 is characterized by: The connection end of the central thin column (6) and the main buoy (2) extends into a cavity inside the main buoy (2) that matches the central thin column (6) and maintains a certain distance from the top of the cavity.

5. The floating offshore wind turbine foundation that can adapt to tide level and is easy to install according to claim 1 is characterized by: The damping buoy (3) is provided with a plurality of damping holes (8) extending through it.

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