Floating tension leg platform system for offshore wind turbines

Abstract

The present invention provides a floating tension leg platform system for an offshore wind turbine. The floating tension leg platform system comprises: a tower adapter assembly connected to the tower of the wind turbine; a plurality of tension legs fixed on the seabed; and a floating platform arranged between the tension legs and the tower adapter assembly, comprising a floating structure and a supporting structure. The floating structure is connected to the tension legs so that the movement of the floating platform is restricted to a specific area, and the supporting structure is connected to the tower adapter assembly so that the floating platform can carry horizontal axis and vertical axis wind turbines.

Description

Technical Field

[0001] The present invention relates to a floating platform for an offshore wind turbine generator, and in particular to a floating tension leg platform (TLP) for a horizontal axis or vertical axis offshore wind turbine generator. Background Art

[0002] Wind turbines can be classified into onshore and offshore wind turbines according to their location. Offshore wind turbines can also be divided into two types: fixed and floating. Fixed offshore wind turbines are fixed to the seabed by piles, for example, on the continental shelf where the water depth is relatively shallow. Since the water depth in the open sea is too deep, the cost of fixing the piles to the seabed may be too high, so fixed offshore wind turbines are not suitable for installation in the open sea. In contrast, floating offshore wind turbines are not limited by the water depth, and are therefore suitable for installation far from the coast or in the open sea.

[0003] Regarding floating offshore wind turbines, technicians face some challenges, mainly related to the construction and installation of structures in harsh offshore environments. These floating offshore wind turbines are subject to strong external forces from waves, tidal forces and wind forces, so appropriate installation facilities must be designed and constructed to high standards. Specifically, the floating platform of the offshore wind turbine must be able to provide sufficient buoyancy and support to carry the wind turbines, while also withstanding the impact of waves, tidal forces, and wind forces. In addition, many of the current semi-submersible platforms are large and heavy, and their anchoring systems occupy too much space, which has an adverse impact on the environment and also increases the carbon footprint. Therefore, there is a need to provide an easy-to-build floating platform for wind turbines to meet carbon economy requirements while ensuring that its structure is strong and resilient. Summary of the invention

[0004] In view of the above problems in the prior art, the present invention proposes a floating tension leg platform system that can be used for horizontal axis and vertical axis offshore wind turbines. Compared with the previous technology, this system is more stable, efficient, economical, and has low carbon characteristics. Due to its excellent stability, this system also improves the efficiency of wind power generation.

[0005] The present invention provides a floating tension leg platform system, comprising: a tower adapter assembly connected to a tower of a wind turbine; a plurality of tension legs fixed on a seabed; and a floating platform arranged between the tension legs and the tower adapter assembly, comprising a floating structure and a supporting structure; wherein the floating structure is connected to the tension legs so that the movement of the floating platform is restricted within a specific area, and the supporting structure is connected to the tower adapter assembly so that the floating platform can carry the wind turbine.

[0006] In one embodiment of the present invention, the floating structure includes a plurality of extension arms and a polygonal flat beam floating body, wherein one end of the extension arms is respectively connected to the tension legs and the other end of the extension arms is respectively connected to the vertices of the polygonal flat beam floating body.

[0007] In one embodiment of the present invention, the support structure includes a plurality of vertical columns and a plurality of inclined columns. When the tower base adapter assembly is located at the center of the polygonal flat beam floating body and the inclined columns are in an inclined condition, one ends of the inclined columns are connected to the tower base adapter assembly together and the other ends of the inclined columns are respectively arranged at the upper ends of the vertical columns, and the bottom ends of the vertical columns are respectively arranged at the vertices of the polygonal flat beam floating body.

[0008] In one embodiment of the present invention, the support structure includes a plurality of vertical columns and a plurality of horizontal columns. When the tower base adapter assembly is located at the center of the polygonal flat beam floating body and the horizontal columns are in a flat position, one ends of the horizontal columns are connected to the tower base adapter assembly together and the other ends of the horizontal columns are respectively orthogonally connected to the upper ends of the vertical columns, and the bottom ends of the vertical columns are respectively arranged on the vertices of the polygonal flat beam floating body.

[0009] In one embodiment of the present invention, the extension arms and the polygonal flat beam floating body are arranged to be located on the same plane.

[0010] In one embodiment of the present invention, the floating structure includes a plurality of extension arms and an annular column, one end of the extension arms is respectively connected to the tension legs, and the other ends of the extension arms are respectively connected to the annular column at equal distances in the circumferential direction of the annular column.

[0011] In one embodiment of the present invention, the support structure includes an independent pillar, one end of the independent pillar is connected to the tower base adapter assembly, and the other end of the independent pillar is connected to the hollow part of the annular column in a shape-matched manner.

[0012] In one embodiment of the present invention, the extension arms and the annular column are arranged to be located on the same plane.

[0013] In one embodiment of the present invention, the extension arms are orthogonally connected to the tension legs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a side view schematic diagram of a horizontal axis offshore wind turbine system, which includes a first embodiment of the floating platform system of the present invention.

[0015] Figure 2 It is a side view schematic diagram of a horizontal axis offshore wind turbine system, which includes a second embodiment of the floating platform system of the present invention.

[0016] Figure 3 At the same time Figure 1 and Figure 2 A top view of the floating platform system.

[0017] Figure 4 It is a side view schematic diagram of a vertical axis offshore wind turbine system, which includes a third embodiment of the floating platform system of the present invention.

[0018] Figure 5 Tie Figure 4 A top view of the floating platform system. DETAILED DESCRIPTION

[0019] In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the preferred embodiments of the present invention are given below and described in detail with reference to the accompanying drawings.

[0020] The drawings in this case are all schematic. Specifically, the proportions, sizes or appearances of the components in the drawings are all schematic and do not represent the actual proportions, sizes or appearances of the components. For example, the thickness, length and proportions of the various components of the wind turbine system and floating platform system (such as the tower, tension legs and vertical columns) in this article are not presented based on the physical dimensions of the actual products. In addition, for the sake of simplicity, in some cases, specific devices or components may only be presented schematically with simple patterns. For example, Figure 1 The wind turbines are shown schematically only in the form of wind blades.

[0021] This article divides the offshore wind turbine system into two parts: the wind turbine system and the floating platform system. The floating platform system is further divided into three parts: the tower adapter assembly, the tension leg and the floating platform. In addition, the floating platform is further divided into two parts: the floating structure and the supporting structure.

[0022] First, please also refer to Figure 1 and Figure 3 . Figure 1 It is a side view schematic diagram of a horizontal axis offshore wind turbine system, which includes a first embodiment of the floating platform system of the present invention. Figure 3 Tie Figure 1 A top view of the floating platform system.

[0023] The horizontal axis offshore wind turbine system 100 includes a wind turbine body 110, a tower base 120, a tower base adapter assembly 130, an inclined support column 140, a vertical column 150, an extension arm 160, a polygonal flat beam float 170, and a tension leg 180. The wind turbine body 110 and the tower base 120 are components of the wind turbine system. The tower base adapter assembly 130, the inclined support column 140, the vertical column 150, the extension arm 160, the polygonal flat beam float 170, and the tension leg 180 are components of the floating platform system. The extension arm 160 and the polygonal flat beam float 170 are classified as floating structures, while the inclined support column 140 and the vertical column 150 are classified as supporting structures. That is, the inclined support column 140, the vertical column 150, the extension arm 160, and the polygonal flat beam float 170 are combined to form the aforementioned floating platform.

[0024] In this embodiment, the tower adapter assembly 130 is connected to the tower 120 of the wind turbine body 110 (i.e., the wind turbine, in this embodiment, a horizontal axis offshore wind turbine). The tension leg 180 is usually fixed on the seabed. The tension leg 180 needs to resist the buoyancy of the floating platform to pull the floating platform, thereby limiting the horizontal movement of the floating platform only within a specific sea area. The tension leg 180 can be composed of a steel cable, a fiber cable or a hollow rod. The floating platform is arranged between the tension leg 180 and the tower adapter assembly 130. The floating platform floats on the water like a hull, and its main function is to carry the wind turbine system so that it can be installed in deeper waters to generate electricity. In one embodiment, the connectors at the top and bottom of the tension leg 180 are provided with a rotating or flexible joint to facilitate connection to the seabed and the floating platform. The connection between the floating platform and the tension leg 180 can be an anchor chain connection, or a locking connection of the connector can be used, but is not limited to this.

[0025] In one embodiment, the number of tension legs 180 is determined according to the structural design of the floating platform, and is usually at least three and is set to a multiple thereof. For example, if the polygonal flat beam buoy 170 of the floating platform is implemented as a triangular structure (i.e., composed of three floating beams), the number of tension legs 180 is usually three or a multiple of three. Similarly, if the polygonal flat beam buoy 170 of the floating platform is a quadrangular structure, the number of tension legs 180 is four or a multiple of four, and so on. Usually, based on cost considerations, the polygonal flat beam buoy 170 is implemented as a triangular structure. In other cases, the polygonal flat beam buoy 170 can be a quadrangular (such as a square, rectangle or trapezoid), pentagonal or hexagonal structure. In various embodiments, the polygonal flat beam buoy 170 can be a symmetrical or asymmetrical polygonal structure. In an embodiment, in order to optimize or simplify the overall structural design, the polygonal flat beam buoy 170 is configured as an equilateral triangle structure. In other embodiments, the polygonal flat beam floating body 170 may be an isosceles triangle structure, a right triangle structure or other triangle structures. For the purpose of illustration and example, the polygonal flat beam floating body 170 is assumed to be a triangle structure. Figure 3 The polygonal flat beam floating body 170 is depicted as an equilateral triangle structure.

[0026] In this embodiment, not only the tension legs 180, but also the numbers of the oblique pillars 140, the vertical pillars 150 and the extension arms 160 are determined according to the structure of the polygonal flat beam floating body 170. For example, if the polygonal flat beam floating body 170 is set as a triangular structure, three oblique pillars 140, three vertical pillars 150, three extension arms 160 and at least three tension legs 180 need to be used accordingly (because one extension arm 160 can be connected to one or more tension legs 180).

[0027] In this embodiment, the floating structure (extension arm 160 and polygonal flat beam floating body 170) is connected to the tension leg 180, and the support structure (diagonal support column 140 and vertical column 150) is connected to the tower adapter assembly 130. In detail, one end of the extension arm 160 is connected to the tension leg 180 respectively and the other end of the extension arm 160 is connected to the vertex of the polygonal flat beam floating body 170 respectively. One end of the diagonal support column 140 is connected to the tower adapter assembly 130 together and the other end of the diagonal support column 140 is respectively arranged at the upper end of the vertical column 150. In addition, the bottom end of the vertical column 150 is respectively arranged on the vertex of the polygonal flat beam floating body 170. It should be noted that in order to balance the force or support force, when the diagonal support column 140 is installed, the tower adapter assembly 130 is located at the center of the polygonal flat beam floating body 170 and the diagonal support column 140 is symmetrically and obliquely arranged around the central axis of the polygonal flat beam floating body 170. In order to easily find the center of the polygonal flat beam floating body 170 and to facilitate the installation of components, preferably, the polygonal flat beam floating body 170 is set to a symmetrical polygonal structure, such as Figures 1 to 3 The equilateral triangle structure shown. As mentioned above, one end of the extension arm 160 is connected to the tension leg 180 and the tension leg 180 can be connected using a connector (not shown). The position of the connector between the tension leg 180 and the extension arm 160 is usually set near the end of the extension arm 160 facing outward. Preferably, the connector is located at the end of the extension arm 160. Each extension arm 160 can be attached with one or more connectors, which can then be connected to one or more tension legs 180.

[0028] In this embodiment, the extension arm 160 and the polygonal flat beam float 170 are configured to be located on the same plane. Preferably, the extension arm 160 is also formed as a float and is orthogonally connected to the tension leg 180. Preferably, the diameter or size of the vertical column 150 is larger than the diameter or size of the floating beam of the polygonal flat beam float 170 and the extension arm 160. The cross-sectional shape of the vertical column 150, the extension arm 160 and the floating beam can be a regular or irregular geometric shape, including but not limited to a circle, a square, a rectangle, an ellipse, a triangle, a pentagon, etc. Preferably, the cross-section of the floating beam is a circle, a square or a rectangle.

[0029] Next, please also refer to Figure 2 and Figure 3 . Figure 2 It is a side view schematic diagram of a horizontal axis offshore wind turbine system, which includes a second embodiment of the floating platform system of the present invention. Figure 3 Tie Figure 2 A top view of the floating platform system.

[0030] The second embodiment of the present invention is similar to the first embodiment in most aspects, and the same parts will not be repeated. The difference between the horizontal axis offshore wind turbine system 100 of the first embodiment and the horizontal axis offshore wind turbine system 100' of the second embodiment lies in the configuration of the inclined struts 140 and the horizontal struts 140'. In the second embodiment, the horizontal struts 140' are configured to be placed horizontally, which is the main difference. However, when viewed from a top view, the floating platform systems of the first embodiment and the second embodiment are the same. For simplicity, the first embodiment and the second embodiment share a top view, as shown in FIG. Figure 3 As shown, the position of the diagonal support 140 also indicates the position of the horizontal support 140', depending on the position of the horizontal support 140'. Figure 1 or Figure 2The embodiment of the invention depends on the embodiment of the invention. In the second embodiment, one end of the horizontal pillar 140' is connected to the tower adapter assembly 130 and the other end of the horizontal pillar 140' is orthogonally connected to the upper end of the vertical pillar 150. The bottom ends of the vertical pillars 150 are respectively arranged on the vertices of the polygonal flat beam float 170. In order to balance the force or support force, when installing the horizontal pillar 140', the tower adapter assembly 130 is located at the center of the polygonal flat beam float 170, and the horizontal pillars 140' are symmetrically arranged around the central axis of the polygonal flat beam float 170. In this embodiment, since the horizontal pillar 140' and the tower adapter assembly 130 are located on the same plane, in order to maintain the wind turbine system (wind turbine body 110 and tower 120) at the same height above the sea level, the length of the vertical column 150 of the second embodiment will be increased relative to the length of the vertical column 150 of the first embodiment (such as Figure 1 and 2 As shown, the dotted line is the sea level, Figure 1 The vertical column 150 is completely immersed in water, Figure 2 The vertical column 150 is partially immersed in the water and partially above the water surface).

[0031] Finally, please also refer to Figure 4 and Figure 5 . Figure 4 It is a side view schematic diagram of a vertical axis offshore wind turbine system, which includes a third embodiment of the floating platform system of the present invention. Figure 5 Tie Figure 4 A top view of the floating platform system.

[0032] The vertical axis offshore wind turbine system 200 includes a wind turbine body 210 (in this embodiment, a vertical axis offshore wind turbine), a tower base 220, a tower base adapter assembly 230, an independent pillar 245, an extension arm 260, an annular column 275, and a tension leg 280. The wind turbine body 210 and the tower base 220 are components of the wind turbine system. The tower base adapter assembly 230, the independent pillar 245, the extension arm 260, the annular column 275, and the tension leg 280 are components of the floating platform system. The extension arm 260 and the annular column 175 are classified as floating structures, while the independent pillar 245 is classified as a supporting structure. That is, the independent pillar 245, the extension arm 260, and the annular column 275 are combined to form a floating platform.

[0033] It should be noted that the "ring" in this article is not limited to a circular ring. The ring can be a triangular ring, a quadrangular ring, or a polygonal ring. For the purpose of illustration and example, the ring column 275 is set as a circular ring column. Figure 5The top view of the annular column 275 is depicted as a circle. In other embodiments, the annular column 275 can be a triangular annular column or a polygonal annular column, etc. In addition, the cross-sectional shape of the independent support 245 and the extension arm 160 can be a regular or irregular geometric shape, including but not limited to a circle, a square, a rectangle, an ellipse, a triangle, a pentagon, etc.

[0034] In the present embodiment, the number of the extension arms 260 is set to three, but is not limited thereto. In other cases, more extension arms 260 may be used. One end of the extension arms 260 are respectively connected to the tension legs 280, and the other ends of the extension arms 260 are respectively connected to the annular columns 275 at equal distances in the circumferential direction of the annular column 275. That is, in order to balance various external forces, the extension arms 260 are evenly spaced and arranged and connected to the circumferential side surfaces of the annular column 275 with the annular column 275 as the central axis. One end of the independent pillar 245 is connected to the tower base adapter assembly 230, and the other end of the independent pillar 245 is connected to the hollow portion of the annular column 275 in a shape-fitting manner. Figure 5 In the embodiment, the hollow portion of the annular column 275 (which is filled with the annular column 275) is set to be circular (the independent pillar 245 and the tower adapter assembly 230 are circular when viewed from a top view), but is not limited thereto. If the independent pillar 245 is a pentagonal pillar, the hollow portion of the annular column 275 will be set to be pentagonal to match the shape of the independent pillar 245, and vice versa. Preferably, the diameter or size of the annular column 275 is twice that of the independent pillar 245. In addition, the extension arm 260 and the annular column 275 are configured to be located on the same plane. The extension arm 260 is orthogonally connected to the tension leg 280.

[0035] The components of the floating platform described herein, including the inclined pillars 140, the horizontal pillars 140', the vertical pillars 150, the extension arms 160, the polygonal flat beam floats 170, the independent pillars 245 and the annular pillars 275, etc., may include materials such as metal (e.g., iron or its alloys, such as steel or stainless steel, etc.), ceramics, plastics, concrete, granular materials, composite materials or other building materials, but are not limited thereto. In addition, Figure 1 and Figure 2 Although the wind turbine body 110 is schematically depicted as a horizontal axis offshore wind turbine, in other embodiments, Figure 1 and Figure 2 The wind turbine body 110 may also be a vertical axis offshore wind turbine. Figure 4 Although the wind turbine body 210 is schematically depicted as a vertical axis offshore wind turbine, in other embodiments, Figure 4 The wind turbine body 210 may also be a horizontal axis offshore wind turbine.

[0036] The floating platform system of the present invention has a smaller footprint than the conventional semi-submersible platform system, thereby reducing the adverse impact on the marine environment. The floating platform system of the present invention can improve the hydrodynamic cancellation effect by adjusting the volume ratio of the vertical column 150 and the polygonal flat beam buoy 170 (for the third embodiment, the independent column 245 and the annular column 275). This helps to stabilize the floating platform and improve weight efficiency during offshore installation, thereby minimizing the wave and current loads on the vertical column 150 and the polygonal flat beam buoy 170, and ultimately reducing the mechanical fatigue of the connectors at the top and bottom of the tension leg 180. In addition, the extension arm 160 increases the distance between the tension leg 180 and the vertical column 150 (for the third embodiment, the tension leg 280 and the independent column 245), and increases the horizontal spacing between the tendon porch of the tension leg 180 and the vertical column 150, which reduces the heave, roll and pitch of the floating platform, so that the floating platform can obtain higher stability. In addition, the floating platform with the extension arm 160 can reduce the translation and rotation between the tension leg 180 and the floating platform, thereby reducing the mechanical fatigue of both and extending their service life. In addition, for the third embodiment, only using independent pillars 245 not only saves installation time, but also further reduces the amount of materials used, thereby reducing overall costs and achieving a carbon reduction effect.

[0037] The above description is for illustrative purposes only and is not intended to be limiting. Any equivalent modifications or changes made thereto without departing from the spirit and scope of the present invention shall be included in the scope of the appended patent applications.

[0038] Explanation of symbols

[0039] 100, 100': Horizontal axis offshore wind turbine system

[0040] 110: Fan body

[0041] 120: Tower base

[0042] 130: Tower adapter assembly

[0043] 140: Inclined pillar

[0044] 140': Horizontal support

[0045] 150: Vertical column

[0046] 160: Extension arm

[0047] 170:Polygonal flat beam floating body

[0048] 180: Tension Leg

[0049] 200:Vertical axis offshore wind turbine system

[0050] 210: Fan body

[0051] 220: Tower base

[0052] 230: Tower adapter assembly

[0053] 245: Independent Pillar

[0054] 260: Extension arm

[0055] 275: Ring column

[0056] 280: Tension Leg

Claims

1. A floating tension leg platform system, comprising: A tower adapter assembly connected to the tower of the wind turbine; A plurality of tension legs fixed to the seabed; as well as A floating platform, disposed between the tension legs and the tower adapter assembly, comprising a floating structure and a supporting structure; The floating structure is connected to the tension legs so that the movement of the floating platform is restricted within a specific area, and the supporting structure is connected to the tower adapter assembly so that the floating platform can carry the wind turbine.

2. The floating tension leg platform system of claim 1, wherein: The floating structure includes a plurality of extension arms and a polygonal flat beam floating body, wherein one end of the extension arms is respectively connected to the tension legs and the other end of the extension arms is respectively connected to the vertices of the polygonal flat beam floating body.

3. The floating tension leg platform system of claim 2, wherein: The support structure includes a plurality of vertical columns and a plurality of inclined columns. When the tower base adapter assembly is located at the center of the polygonal flat beam floating body and the inclined columns are inclined, one ends of the inclined columns are connected to the tower base adapter assembly and the other ends of the inclined columns are respectively arranged at the upper ends of the vertical columns, and the bottom ends of the vertical columns are respectively arranged at the vertices of the polygonal flat beam floating body.

4. The floating tension leg platform system of claim 2, wherein: The support structure includes a plurality of vertical columns and a plurality of horizontal columns. When the tower base adapter assembly is located at the center of the polygonal flat beam floating body and the horizontal columns are in a flat position, one ends of the horizontal columns are connected to the tower base adapter assembly and the other ends of the horizontal columns are orthogonally connected to the upper ends of the vertical columns, and the bottom ends of the vertical columns are respectively arranged on the vertices of the polygonal flat beam floating body.

5. The floating tension leg platform system of claim 2, wherein: The extension arms and the polygonal flat beam floating body are arranged to be located on the same plane.

6. The floating tension leg platform system of claim 1, wherein: The floating structure includes a plurality of extension arms and an annular column. One ends of the extension arms are respectively connected to the tension legs, and the other ends of the extension arms are respectively connected to the annular column at equal distances in the circumferential direction of the annular column.

7. The floating tension leg platform system of claim 6, wherein: The supporting structure comprises an independent pillar, one end of which is connected to the tower base adapter assembly, and the other end of which is connected to the hollow part of the annular column in a shape-matched manner.

8. The floating tension leg platform system of claim 6, wherein: The extension arms and the annular column are arranged to be located on the same plane.

9. The floating tension leg platform system of claim 2 or 6, wherein: The extension arms are orthogonally connected to the tension legs.

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