Mooring structure suitable for wind power floating type foundation

Abstract

The utility model discloses a mooring structure suitable for a wind power floating type foundation. The mooring structure comprises an anchoring device, a stiffness spring and a mooring cable. The anchoring device is anchored on the seabed, one end of the mooring cable is fixedly connected with the anchoring device, the other end of the mooring cable is fixedly connected with the floating type foundation through the stiffness spring, and the wind turbine generator is arranged on the floating type foundation. The floating type foundation has the advantages of being even in stress, simple in structure, convenient to manufacture and the like, the mooring rope and the floating type foundation are connected through the rigid springs, due to the fact that the springs provide the flexible buffering function, the motion position of the floating type foundation is effectively restrained, instantaneous external loads borne by a wind turbine generator are greatly relieved, the structural stability of the wind turbine generator is improved, and the service life of the wind turbine generator is prolonged. And the influence of high-frequency vibration on the performance of the floating type wind turbine generator is effectively reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of offshore floating wind power generation, and particularly relates to a mooring structure suitable for a floating foundation of a wind power. Background Art

[0002] With the development of the wind power industry, it is an inevitable trend in the future to develop floating offshore wind power technologies applicable to deeper sea areas. An offshore floating wind turbine unit consists of a wind turbine, a tower, a floating foundation and a mooring system. The floating foundation is a platform floating on the sea surface. Different from a fixed wind turbine unit, the floating foundation has certain six-degree-of-freedom motions under the action of ocean environmental loads. The mooring system is used to fix the position on the seabed, and the stability of the foundation structure of the offshore wind turbine unit is maintained through the balance of its own gravity, mooring cable restoring force and structural buoyancy. The wind turbine is located at an altitude of nearly 100 meters above the sea surface. A slight movement of the floating foundation can cause violent movements of the wind turbine unit, which poses high requirements for the design of the mooring system.

[0003] The mooring system is a key component connecting the floating foundation and the seabed, and mainly has three forms: catenary type, taut type, and tension leg type. The floating wind turbine needs to be restricted in position and motion through the mooring system. During the normal use stage, the mooring system can ensure the stability of the floating foundation structure. In the event of extreme sea conditions, the mooring system can ensure the safety of the floating foundation. Although the existing mooring systems can meet the current requirements, there are still the following main problems:

[0004] First, the catenary mooring system has a large range of constraints on the movement position of the floating foundation. The platform is subjected to large wave forces and responds violently during the rolling and pitching motions in high-wind and high-wave sea areas, which easily causes the swing amplitude of the wind turbine unit to be too large and strong impacts, and cracks are likely to occur in the weak parts of the structure, seriously affecting the structural stability of the wind turbine. Investigations and studies have shown that the cracks that appear in the structure are the fundamental reasons for the reduction of the structural durability of the wind turbine unit and even major safety accidents.

[0005] Second, the tension leg mooring system uses tension legs to anchor to the seabed. Due to the action of the pre-tensioned mooring system, the tension leg foundation has a very high rigidity, ensuring very good stability. Theoretically, the greater the pre-tension force of the mooring system borne by the tension leg foundation, the more stable the platform can be achieved. However, at the same time, the high-frequency vibration has a relatively large impact on the performance of the floating wind turbine unit. When designing the foundation, it is necessary to avoid the natural period that coincides with the floating foundation in the environment. In addition, the tension leg bears a large load, and the installation process of the tension mooring system is complex and costly.

[0006] Third, the tension mooring system uses steel cables or other synthetic materials, mainly relying on the elastic deformation of the mooring cables to provide restoring force, which has obvious economic advantages over the steel chain structure, especially in deep water areas. However, the mooring cables are in a tensioned state, and the seabed anchorage section bears both horizontal and vertical forces, requiring higher bearing performance of the anchorage foundation. The mooring cable stiffness has large non-linear characteristics such as relaxation and creep, increasing the difficulty and cost of operation and maintenance.

[0007] To comprehensively solve the above problems, a new mooring structure suitable for the floating foundation of wind turbines is designed to transfer and buffer the external forces received by the wind turbine foundation. Summary of the Utility Model

[0008] The technical problem to be solved by the present utility model is to provide a mooring structure suitable for the floating foundation of wind turbines with uniform stress, simple structure and convenient manufacturing in view of the deficiencies of the existing mooring structures for floating foundations. To achieve the above object, the present utility model can adopt the following technical solutions:

[0009] A mooring structure suitable for the floating foundation of wind turbines, comprising an anchoring device, a stiffness spring and a mooring cable; the anchoring device is anchored to the seabed, one end of the mooring cable is fixedly connected to the anchoring device, and the other end of the mooring cable is fixedly connected to the floating foundation through the stiffness spring.

[0010] As a further improvement of the present utility model, the stiffness spring is installed at a position above the water surface of the floating foundation.

[0011] As a further improvement of the present utility model, a spring sheath is sleeved outside the stiffness spring.

[0012] As a further improvement of the present utility model, the mooring cable is made of synthetic fiber ropes.

[0013] As a further improvement of the present utility model, multiple mooring cables are arranged radially.

[0014] As a further improvement of the present utility model, the anchoring device adopts a pile anchor, a suction bucket anchor or a gravity anchor.

[0015] Compared with the prior art, the advantages of the present utility model are as follows:

[0016] The mooring structure applicable to the floating foundation of wind power of the present utility model connects the mooring cable and the floating foundation by setting a stiffness spring. Since the spring provides a flexible buffering effect, it effectively restricts the movement position of the floating foundation, reduces the elastic deformation and stress relaxation of the mooring cable, greatly alleviates the instantaneous external load on the wind turbine, improves the structural stability of the wind turbine, and effectively reduces the performance impact of high-frequency vibration on the floating wind turbine. The mooring structure of the present utility model can well adapt to the application scenario of large-power floating wind turbines at sea, and has the advantages of reasonable force, simple structure, convenient manufacturing, and low cost. Brief Description of the Drawings

[0017] Figure 1 It is a schematic diagram of the main structure principle of the mooring structure applicable to the floating foundation of wind power in a specific embodiment of the present utility model;

[0018] Figure 2 It is a schematic diagram of the local structure principle of component connection in a specific embodiment of the present utility model;

[0019] Legend: 1. Wind turbine; 2. Floating foundation; 3. Anchoring device; 4. Stiffness spring; 5. Spring sheath; 6. Mooring cable. Detailed Embodiment

[0020] The following further describes the present utility model in conjunction with the accompanying drawings of the specification and specific preferred embodiments, but does not limit the protection scope of the present utility model thereby.

[0021] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "side", "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model 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 thus cannot be understood as a limitation of the present utility model.

[0022] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, "a plurality" means two or more unless otherwise specifically defined.

[0023] Embodiment

[0024] As Figure 1 and Figure 2 shown, the mooring structure of the present utility model applicable to the floating foundation of wind power includes an anchoring device 3, a stiffness spring 4 and a mooring cable 6. The anchoring device 3 is anchored to the seabed. One end of the mooring cable 6 is fixedly connected to the anchoring device 3, and the other end of the mooring cable 6 is fixedly connected to the floating foundation 2 through the stiffness spring 4. The wind turbine 1 is arranged on the floating foundation 2. During the service life of the wind turbine 1, each mooring cable 6 is always in a tension state to restrict the free movement and rotation of the entire floating body composed of the floating foundation 2 of the wind turbine 1, ensuring the safe operation of the wind turbine 1.

[0025] In this embodiment, by setting the stiffness spring 4 to connect the mooring cable 6 and the floating foundation 2, since the spring provides a flexible buffering effect, it effectively restricts the movement position of the floating foundation 2, reduces the elastic deformation and stress relaxation of the mooring cable, greatly alleviates the instantaneous external load on the wind turbine 1, improves the structural stability of the wind turbine 1, and effectively reduces the influence of high-frequency vibration on the performance of the floating wind turbine.

[0026] As Figure 2 shown, the stiffness spring 4 is installed at the part of the floating foundation 2 above the water surface, which is simple and convenient to maintain.

[0027] As Figure 2 shown, a spring sheath 5 is sleeved outside the stiffness spring 4 for protection to improve the service life of the stiffness spring 4.

[0028] In this embodiment, the mooring cable 6 is made of a synthetic fiber rope. The synthetic fiber rope has a small stiffness and a small stretching degree, provides a large horizontal restoring force, and multiple mooring cables 6 are arranged radially to control the horizontal displacement of the floating foundation 2 and ensure the stability of the floating foundation 2.

[0029] In this embodiment, the anchoring device 3 adopts a pile anchor. In other embodiments, the anchoring device 3 can also adopt a suction bucket anchor or a gravity anchor.

[0030] The mooring structure of this embodiment effectively reduces the external load on the wind turbine 1, realizes low-stress transmission between the wind turbine 1 and the anchoring device 3, and also realizes the automatic positioning of the floating foundation 2, improving the reliability of the wind turbine 1.

[0031] Although the present utility model is disclosed above in preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present utility model by using the methods and technical contents disclosed above, or modify it into equivalent embodiments with equivalent changes, without departing from the spirit and technical solution of the present utility model. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model still fall within the scope of protection of the technical solution of the present utility model.

Claims

1. A mooring structure suitable for a floating foundation of wind power, characterized in that: It comprises an anchoring device (3), a stiffness spring (4) and a mooring cable (6); the anchoring device (3) is anchored on the seabed, one end of the mooring cable (6) is connected and fixed to the anchoring device (3), and the other end of the mooring cable (6) is connected and fixed to the floating foundation (2) via the stiffness spring (4).

2. The mooring structure suitable for a floating foundation for wind power generation according to claim 1, characterized in that: The stiffness spring (4) is installed at a position above the water surface of the floating foundation (2).

3. The mooring structure suitable for a floating foundation for wind power generation according to claim 2, characterized in that: A spring sheath (5) is sleeved on the outer side of the stiffness spring (4).

4. The mooring structure suitable for a floating foundation for wind power generation according to any one of claims 1 to 3, characterized in that: The mooring cable (6) is made of synthetic fiber rope.

5. The mooring structure suitable for a floating foundation for wind power generation according to claim 4, characterized in that: A plurality of mooring cables (6) are arranged radially.

6. The mooring structure suitable for a floating foundation for wind power generation according to any one of claims 1 to 3, characterized in that: The anchoring device (3) adopts a pile anchor, a suction bucket anchor or a gravity anchor.

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