GB2609466A

GB2609466A - A floating wind turbine platform

Info

Publication number: GB2609466A
Application number: GB2111176.0A
Authority: GB
Inventors: Campos Antunes Ferrao Jorge
Original assignee: Aker Offshore Wind AS
Current assignee: Aker Offshore Wind AS
Priority date: 2021-08-03
Filing date: 2021-08-03
Publication date: 2023-02-08
Anticipated expiration: 2041-08-03
Also published as: KR20230020891A; GB2609466B; KR20230020337A; KR102573788B1; GB202111176D0

Abstract

A floating wind turbine platform 104 comprises a hull configurable to support a wind turbine tower. The hull comprises a first, second and third column 106a-c, the first, second and third columns being connected by a first, second and third pontoon member (112a-c, Fig 2), as well as by a first, second and third connector 122a-c. Each of the first, second and third columns may comprise an axial intersecting surface (118, Fig 4) for engagement with a pontoon member.

Description

A floating wind turbine platform

Technical field

The present disclosure relates to a floating wind turbine platform. More specifically, the disclosure relates to a floating wind turbine platform as defined in the introductory parts of and claim 1.

Background art

Floating, offshore wind energy converters are being studied and developed by various research and development (R&D) groups, both within academia and industry. While not yet in widespread commercial use, it is expected that further development of floating offshore wind technology will make such plants more competitive and a viable alternative for many locations in the near future.

A challenge associated with floating offshore wind energy converters is their construction and installation in an offshore location. While onshore construction may be more easily achieved, this may cause problems later, as a large structure may then require to be moved to an offshore location. Alternatively, transporting parts of a floating offshore wind energy converter to an offshore location may be relatively simple, but subsequent construction in an offshore location may be problematic.

Due to the large forces that are experienced by floating offshore wind energy converters, both due to wave and tidal forces, and wind forces, it is important that floating offshore wind energy converters be designed and constructed to a high quality. In particular, a platform of a floating wind energy converted must be constructed to be able to provide buoyancy, as well as support a wind turbine tower and withstand direct wave and tidal forces. Therefore, there is a need for a platform for a floating wind turbine that has both structurally sound and easy to construct.

Summary

It is an object of the present disclosure to mitigate, alleviate or eliminate one or more of the above-identified deficiencies and disadvantages in the prior art. According to a first aspect there is provided a floating wind turbine platform comprising a substantially triangular hull configurable to support a wind turbine tower. The hull comprises a first, second and third column, the first, second and third columns being connected by a first, second and third pontoon member, as well as by a first, second and third connector.

Further aspects and embodiments according to the present disclosure will become apparent from the detailed description given below. The detailed description and specific examples disclose preferred embodiments of the disclosure by way of illustration only. Those skilled in the art understand from guidance in the detailed description that changes and modifications may be made within the scope of the disclosure.

Hence, it is to be understood that the herein disclosed disclosure is not limited to the particular component parts of the device described or steps of the methods described since such device and method may vary. It is also to be understood that the terminology used herein is for purpose of describing particular embodiments only, and is not intended to be limiting. It should be noted that, as used in the specification and the appended claim, the articles "a", "an", "the", and "said" are intended to mean that there are one or more of the elements unless the context explicitly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, and the like. Furthermore, the words "comprising", "including", "containing" and similar wordings does not exclude other elements or steps.

Brief descriptions of the drawings

The above objects, as well as additional objects, features and advantages of the present disclosure, will be more fully appreciated by reference to the following illustrative and non-limiting detailed description of example embodiments of the present disclosure, when taken in conjunction with the accompanying drawings.

Figures la-b shows an example of a known wind turbine and floating platform.

Figure 2 is an exemplary plan view of a floating platform according to the present

disclosure.

Figure 3 is a perspective view of a floating platform according to the present disclosure. Figure 4 is a schematic top view of parts of a platform.

Figures 5a-c and 6a-c schematically illustrate various ballast arrangements in a floating 30 platform.

Figures 7 and 8 illustrate aspects of a platform in an embodiment.

Detailed description

The present disclosure will now be described with reference to the accompanying drawings, in which preferred example embodiments of the disclosure are shown. The disclosure may, however, be embodied in other forms and should not be construed as limited to the herein disclosed embodiments. The disclosed embodiments are provided to fully convey the scope of the disclosure to the skilled person.

In this disclosure, the terms 'side' and 'surface' are used interchangeably and indicate a side or a surface of a hull for example defined by a steel plate. While terms such as 'inner', outer', 'external' and 'internal' are used in the description, it should be understood that these may be used to indicate relative positions or orientations relative to e.g. the triangle centre / centroid or other components. Unless otherwise indicated, sides and surfaces discussed in this disclosure refer to outside faces of the hull, i.e. not sides or surfaces located inside the hull.

(As will be clear, the hull may have a number of other structural elements on its inside, such as strengthening plates etc., which are not described here.) Figures la-b show an example of a known offshore wind energy converter 10 comprising a floating wind turbine 2 and floating platform 4. Here, the floating platform 4 comprises three cylindrical columns 6, which are connected together by a number of upper supports 8 and lower supports 12 in a triangular formation. Mounted to the floating platform 4 via one of the cylindrical columns 6 is a wind turbine tower 14. The floating platform 4 may be positioned in an offshore location and may provide support and buoyancy for the wind turbine tower 14. As illustrated, the floating platform 4 comprises a plurality of anchor points 16, which serve the purpose of anchoring the wind energy converted 10 in a desired position in an offshore location. In particular, an anchor point 16 is located on each of the columns 6.

Figure 2 illustrates a view of the underside of a floating platform 104 according to an aspect of the present disclosure, while Figure 3 illustrates a perspective view of a floating platform 104. In Figure 2, the floating platform 104 comprises a hull that is comprised of a first, second and third column 106a-c, which are connected together by a first, second and third pontoon member 112a-c. In this example, the pontoon members 112a-c are connected in the form of a triangle, although the skilled reader will understand that other connection configurations may be possible that result in alternative shapes of the floating platform 104.

While in the example of Figures la-b the columns 6 have a cylindrical shape, in the example of Figure 2, it can be seen that the columns have a lateral cross-section that is in the shape of an irregular polygon. As such, the columns in the example of Figure 2 (and as can also be seen in Figure 3) are in the shape of an irregular polygonal prism. In particular, the columns have a lateral cross-section in the shape of an irregular hexagon, although it should be appreciated that other shapes of lateral cross-section may be possible (e.g. an irregular pentagon shape). Having the columns 106 in the shape of an irregular polygon may assist in the construction of the floating platform 104, as it may permit the columns to be more simply constructed, for example out of flat panels which may be relatively simply connected together (e.g. by welding, bolting etc.). As will be further described, the shape of the columns may additionally permit a simpler and more structurally sound connection with a corresponding pontoon member 112a-c.

Here, the columns 106a-c have a lateral cross-section shaped so as to enable the connection of a pontoon member 112a-c relative to an intersecting surface 118 such that the intersecting surface extends (e.g. longitudinally extends) perpendicular to the longitudinal axis of the pontoon member 112a-c connecting to the column 106a-c. The intersecting surface 118 corresponds to an external surface of each of the columns 106a-c that, as will be described later, may correspond to a flat panel used to construct the column 106a-c. The pontoon member 112a-c may be connected directly to the intersecting surface 118, or may be connected adjacent the intersecting surface.

As illustrated in both Figures 2 and 3, columns 106a-c are located at each apex of the triangular shaped floating platform 104. The columns 106a-c of this example have a lateral cross-section of an irregular hexagon, three sides of which define the shape of each apex of the floating platform 104 (in the form of a truncated apex). The three sides defining the apex of the floating platform 104 may be considered to be the externally facing sides of the column 106a-c, while the remaining three sides may be considered to be internally facing sides. Two of the remaining three sides (e.g. two of the internally facing sides) define intersecting surfaces 118, which are angled so as to enable connection of a pontoon member relative to a column such that the longitudinal axis of the pontoon member 112a-c is perpendicular, or substantially perpendicular, to the intersecting surface 118. Finally, each of the columns 106a-c defines an intermediate plate 120 positioned between the point of intersection (e.g. connection) between the pontoon members 112a-c. In some examples, the intermediate plate 120 may be absent, in which case each of the intersecting surfaces may be directly adjacent. The column in such a case may have a lateral cross-section in the shape of a pentagon.

Having a pontoon member 112a-c that intersects a column 106a-c such that the longitudinal axis of the pontoon member 112a-c is perpendicular to the intersecting surface of the column 106a-c may provide a platform that is more structurally sound and easier to construct than what is known. For example, the area of intersection between the pontoon member 112a-c and the column 106a-c is reduced compared to the pontoon members 112a-c intersecting the columns 106a-c at an oblique angle.

The columns 106a-c may be constructed from a plurality of flat panels. The flat panels may be connected together by welding, bolting, or the like. In order to construct columns 106a-c having a lateral cross-section of an irregular polygon, several flat panels having differing widths may be connected together along a longitudinal edge to form the columns.

Although each of the flat panels may have differing widths, the flat panels may have identical lengths. By forming the columns 106a-c with a plurality of flat panels, it may be possible to achieve the lateral cross-section as illustrated in Figures 2 and 3, having an intersecting surface 118 for connection of each pontoon member 112a-c thereto. By varying the width of one, some or all of the flat panels, the designer may be able to vary the lateral cross-sectional shape of the columns 106a-c, depending on their specific needs.

Each pontoon member 112a-c may connect to a column 106a-c in any appropriate way. For example, the pontoon member may connect directly to an intersecting surface 118, for example by bolting, welding, or the like, and such one end of the pontoon member (e.g. the entire lateral area of the end of the pontoon member) abuts against the intersecting surface 118 of the column 106a-c. Alternatively, a or each pontoon member 112a-c may connect adjacent (e.g. directly adjacent) an intersecting surface. In the normal orientation of the floating platform 104, the pontoon member 112a-c may connect directly below intersecting surface 118. In such cases, the pontoon member 112a-c may connect to a column 106a-c around its periphery, or may connect to the base of the column 106a-c.

In Figure 3, an example is shown whereby the pontoon members connect to the base of the columns 106a-c. In this example, the pontoon members may be in the form of a triangular collar, the corners of which may connect to the base of the columns 106a-c. In this example, each of the pontoon members 106a-c may be connected together at the ends thereof. The corners of the triangular collar may be shaped so as to be flush with the sides of the externally facing sides of the columns 106a-c.

As will be described in further detail in the following paragraphs, the pontoon members may be hollow, and/or may comprise equipment therein. Is some examples the pontoon members may comprise a ballast arrangement therein which may be operable by a user to vary the buoyancy of the floating platform 104.

Although not illustrated in Figure 2, the columns 106a-c may also be connected together via a plurality of connectors 122a-c. The plurality of connectors 122a-c may connect to the columns above the point of connection with the pontoon members 112a-c and may function to provide structural support. The connectors 122a-c may extend parallel to the pontoon members 112a-c, or may extend at an angle thereto. One single connector 122a-c may extend between each column 106a-c, or a plurality of connectors 122a-c may extend between the columns 106a-c. The connectors 122a-c may have a smaller cross-sectional area than the pontoon members 112a-c. One example of connectors 122a-c is illustrated in Figure 3. In this example, the connectors 122a-c are in the form of a triangular collar that is connected to the top of the columns 106a-c. As such, in this example, the connectors 122a-c are connected to each adjacent connector 122a-c at one end thereof, similar to the configuration of the pontoon members 112a-c. Also similar to the configuration with the pontoon members 112a-c. The connectors 122a-c are connected to the columns such that the part of each connector 122a-c that is connected to the top of each column 106a-c is flush relative the externally facing sides of each column 106a-c. Such a configuration may improve the structural design of the floating platform 104 by removing any ledges or angles which may form stress concentration points on the floating platform in use 104.

In other examples, the connectors may take an alternative form. For example the connectors may be in the form of cylindrical beams that connect to the side of each of the columns 106a-c. Similar to the pontoon members, one end of each of the connectors 122a-c may abut a surface of the columns 106a-c. Alternatively, each of the connectors 122a-c may connect to a column 106a-c via a connection interface, such as via a pin connector or threaded connector.

A cross-sectional shape of the columns 106a-c according to one example is shown in greater detail in Figure 4. Here, the first column is illustrated relative to a regular hexagon 130 having side length a. As illustrated, the cross-section of the column 106a is symmetrical about a central axis 132 extending between the centre of the cross-section and the centre of the floating platform 104, e.g. when viewed from above. However, about a lateral axis 134 rotated degrees the cross-section is asymmetrical. The lateral axis 134 divides the cross-section in two, such that three internal sides of the hexagon lie on one side of the lateral axis 134 proximal the adjacent pontoon members 112a, 112c, while the remaining three external sides of the hexagon lie on the other side of the lateral axis 134. The three internal sides comprise one intermediate side and two adjoining sides to the external sides, and the three external sides comprise one intermediate side and two adjoining sides to the internal sides. Each of the intermediate sides is parallel to the lateral axis 134, while each of the adjoining sides extends obliquely relative to the lateral axis 134.

As illustrated in Figure 4, two variables of the shape of the cross-section are h1 and h2. h1 corresponds to the distance of the internal intermediate side from the lateral axis 134, while h2 corresponds to the distance of the external intermediate side from the lateral axis 134.1n this example the distance h2 is greater than h1.

Three further illustrated variables are b1, b2 and b3. b1 and b3 correspond to the length of the internal and external intermediate sides, respectively, while b2 corresponds to the overall length of the cross-section in a direction along the lateral axis 134.

By varying h1, h2, b1, b2 and b3 various forms of irregular hexagon are possible. In the illustrated example, the variables have been chosen such that the angle between the corresponding internal and external adjoining sides is 90 degrees. Equally, the variables have been chosen such that there is an angle of 30 degrees between the external adjoining sides and the central axis 132. This particular configuration permits the external adjoining sides to extend parallel to the length of the adjacent pontoon members, while the internal adjoining sides extend perpendicular to the length of the adjacent pontoon members. As such, the external adjoining sides are able to be located flush with an external surface of the adjacent pontoon members 112a,c, while the internal adjoining sides (which also are part of the intersecting surface) are able to join to the adjacent pontoon members 112a, 112c at a right angle.

As can also be seen, the angle between the internal adjoining sides and the internal intermediate side is greater than the angle between the external adjoining sides and external intermediate side. This, and the other variables have the effect of a greater area being encapsulated between the lateral axis 134 and the external sides compared to the area encapsulated between the lateral axis 134 and the internal sides. More specifically, given that the angles between the sides of a regular hexagon are 120 degrees, the angle between the internal adjoining sides and the internal intermediate side may be greater than 120 degrees, while the angle between the external adjoining sides and the external intermediate side may be less than 120 degrees. The variables may be chosen such that the total area of the cross-section is the same as would be the case if it were a regular hexagon.

In some examples, the length b1 may be reduced or extended, depending on the width of the pontoon members, for example. Here, the internal intermediate side is shorter than the external intermediate side, although it should be appreciated that in some examples, both intermediate side may be the same length, or the external intermediate side may be the shorter side.

Figures 5a-c and 6a-c illustrate two examples of a floating platform 104 comprising a ballast arrangement 124 therein. The ballast arrangement 124 may be in the form of a ballast compartment or a number of ballast compartments contained within the floating platform 104 (e.g. within a hollow section of the floating platform 104). Each ballast compartment may be in the form of a void within the floating platform 104. The ballast compartments may comprise a ballast tank configured to hold a liquid such as freshwater or seawater, or may be configured to hold a solid ballast material which may be removed and inserted as necessary. In some examples, a ballast compartment, or the ballast compartments, may comprise a plurality of ballast tanks therein.

Figure Sa illustrates a plan view of a floating platform 104, illustrating a triangular-shaped pontoon base and a first, second and third column 106a-c located at each corner thereof. Figure 5b illustrates an elevation view of the floating platform 104 from the viewpoint A-A, while Figure Sc is an elevation view of the floating platform 104 from the viewpoint B-B.

In this example, a first ballast compartment 140 is located along the entire length of the pontoon member 112b, located between the second and third columns 106b, 106c, while part of pontoon members 106a, 106c also comprise the first ballast compartment 140. As the pontoon base is in the form of a triangle, the first ballast compartment 140 may be considered to be located along the entire length of the pontoon member 112b oppositely disposed from the first column 106a. In this example, the section of the first and third pontoon members 112a, 112c that may be considered to be adjacently disposed to the second pontoon member 112b (and to the first column 106a) comprise part of the ballast compartment 140. The ballast compartment 140 may extend part way along the first and third pontoon members 112a, 112c, for example half way along, two-thirds of the way along, one-third of the way along, one-quarter of the way along, or the like. The ballast compartment 140 may be one single compartment (e.g. containing one continuous void for placement of a ballast material or liquid), or may comprise multiple compartments and/or voids, for example one compartment/void in the second pontoon member 112b, and one compartment in each of the first and the third pontoon members 112a, 112c.

The first ballast compartment 140 may be a void in one or more pontoon members 112a-c, and then a ballast tank may be set into the pontoon members 112a-c. Alternatively the ballast tank may be formed by the material of the pontoon members 112a-c themselves (e.g. a sealed void within the pontoon members), meaning that no separate ballast tank is required to be formed into the pontoon members 112a-c. In some examples, the pontoon members 112a-c may comprise a bulkhead or multiple bulkheads. The or each bulkhead may define a boundary of a corresponding ballast compartment or tank. A bulkhead may be located, for example, at the centre of the opposite pontoon member 112b, and may be longitudinally moveable therealong to vary the volume of the first ballast compartment 140 on either side of the bulkhead. In the case where the first ballast compartment 140 is configurable to contain a liquid such as water, the bulkhead may be able to be pressed into the liquid volume in the ballast compartment, so as to remove any residual gas therein, thereby removing any liquid/gas boundary and ridding the ballast compartment of unwanted surface effects due to motion of the floating platform 104.

In addition, here the bottom of the first column 106a comprises a second ballast compartment 142. The second ballast compartment 142 may be in the form of a base unit 142, which may be incorporated into the first column 106a, or connectable thereto. In some examples, the bottom of the first column 106a (as illustrated in Figures 5a to c) including the second ballast compartment 142 may be considered to form part of the pontoon base 120.

The second ballast compartment 142 may be formed in the base of the first column 101, and may not extend higher than the uppermost surface of pontoon base. The intersection between the pontoon member 120d-f and the column 110 may conveniently form, or assist to form, a compartment at the base of the column 110 in which the ballast compartment 142 may be located.

As with the ballast compartment 140, the second ballast compartment 142 may comprise a ballast tank, or the material of the column 106a may define the ballast compartment. Where the second ballast compartment is a base unit 142, the base unit may be or define a ballast tank, connectable to the first column 106a. In some example, the column 106a, the second ballast compartment 142 may comprise a bulkhead therein, which also may be used to remove or reduce surface effects.

Illustrated in Figure 5b, the second ballast compartment 142 may comprise an upper and a lower portion. The upper portion may be located above the height of the uppermost surface of the pontoon member 112a-c, whereas the lower portion may be located below the height of the uppermost surface of the pontoon member 112a-c, as is illustrated. The upper and lower portions may be connected and/or in fluid communication, or may be separate from one another. The upper portion may comprise an upper ballast tank, whereas the lower portion may comprise a lower ballast tank. In some examples, the upper and lower portions may comprise a single ballast tank spanning both portions.

The second ballast compartment 142 may be in fluid communication with the first ballast compartment 140, for example via a ballast liquid transfer arrangement. For example, tubing or piping may extend in the floating platform 104 between the first and second ballast compartments 140, 142, which may enable a user to transfer ballast liquid between the first and second ballast compartments 140, 142, thereby enabling simple and quick redistribution of weight of the floating platform 104.

This ballast arrangement 124 may provide for stability during operation, as it may enable the floating platform 104 to be weighted so as to offset the weight of the wind turbine tower 102 by optionally providing a counterweight at the opposite end of the floating platform 104.

The example of 6a-c provides a different configuration of a ballast arrangement 124. As in the previous example the first column 106a comprises a second ballast compartment 142, which will not be described further.

In this example, the first ballast compartment 140 is located along the entire length of the pontoon member 112b (as in previous examples), located between the second and third columns 111, 112. In contrast to the previous example, the first ballast compartment 140 is contained within the pontoon member 112b and does not extend into adjacent pontoon members 112a, 112c. However, in this example, the second and third columns 106b, 106c also contain ballast compartments, which may be in the form of base units as previously described.

The ballast compartment of the second and third columns 106b, 106c may form part of the first ballast compartment 140, or they may be separate ballast compartments (e.g. in the form of base units), self-contained within each column 106b, 106c.

As is best illustrated in Figures 6b and 6c, the ballast compartment of the second and third columns 106b, 106c may be shallower than that in the pontoon member 112b, and even than that of the first column 106a. In some examples, the ballast compartment of the second and third columns 106b, 160c may hold a solid ballast material, while the pontoon member 112b may hold a liquid ballast material (or vice versa). Although illustrated as being shallower than the ballast compartments of both the pontoon member 112b and the first column 106a, in some examples it may be possible that the ballast compartment is deeper than one or both of the aforementioned.

The configuration of ballast arrangement 124 of Figures 6a-c may provide an alternative weight distribution to that previously described in Figures 5a-c.

In any of the embodiments claimed or described herein, the pontoon member 112b which is located opposite the tower may be configured to hold more liquid ballast than the column 106a or the corner part associated with the tower column. Advantageously, the pontoon member 112b may be configured to hold more liquid ballast than the tower column or corner part by a factor of two, three or four (i.e., more than double, more than three times or more than four times the liquid ballast capacity of the tower column or corner part).

In any of the embodiments claimed or described herein, each of the two pontoon members 112a,c extending from the tower column or corner part associated with the tower column may be configured to hold more liquid ballast in a distal half of the respective pontoon member than in the half of the pontoon member which is proximal to and connects to the tower column or corner part. (See, for example, Fig. 5A.) This can, for example, be realised by arranging liquid ballast tanks in a part of the pontoon member 112a,c which is closer to a distal column 106b,c than to the tower column 106a.

In both the ballast arrangements 124 of Figures 5a-c and 6a-c, it may be possible to vary the ballast weight provided by each ballast compartment, thereby enabling a substantial degree of control over the weight distribution, centre of gravity and overall weight of the wind turbine platform 100. For example, a lighter platform may be useful during installation and maintenance. Depending on the stage of installation (e.g. whether only the turbine tower is mounted on the floating platform 104, or both the tower and the nacelle with blades), variation of the centre of gravity of the floating platform 104 may be a desirable feature.

Variation of the weight and/or the centre of gravity of the floating platform 104 may provide easier access and/or improved stability of the floating platform 104 and the wind turbine platform 100 overall.

Referring now to again to Figure 4, in some embodiments each of the first, second and third columns 106a-c may comprise an inner intermediate side 150 and an outer intermediate side 151, where the inner and outer intermediate sides 150,151 are arranged parallel to each other and perpendicular to an axis 132 extending between the centre of the lateral cross-section (i.e. a centre point laying on the axis 132) and the centre of the floating platform 104, i.e. the triangle centre / centroid. The terms 'outer' and 'inner' refer to the position relative to the triangle centre / centroid, i.e. such that the outer intermediate side 151 is farther away from the centroid than the inner intermediate side 150.

Advantageously, a horizontal length b1 of the inner intermediate side 150 can be equal to or smaller than the horizontal length b2 of the outer intermediate side 151.

Each of the first, second and third columns 106a-c may further comprise a first external side 152 adjoining a first intersecting surface 118 and a second external side 153 adjoining a second intersecting surface 118. Advantageously, the first and second external sides 152,153 can each be arranged flush with an outer side 154,155 of a respective pontoon members 112a-c. (See also Fig. 2.) Alternatively, or additionally, the first and second external sides 152,153 can each be arranged flush with an outer side 149 (see Fig. 8) of a respective connector 122a-c.

Illustrated in Fig. 7, optionally on each of the three sides of the substantially triangular hull, the respective external side 152,153 of the column 106a-c, the outer side 154,155 of the pontoon member 112a-c and the outer side 149 of the connector 122a-c can be arranged to be coplanar. (As indicated by the hatched area in Fig. 7.) The above options can, for example, be obtained by constructing the hull from flat plates, such as steel plates. Having such flush and/or coplanar surfaces can provide manufacturing advantages and benefits in relation to the hull's structural strength, for example that internal reinforcement members can be easier employed during manufacturing onto or between separate construction plates arranged with zero or ninety degree angles between them.

Referring now to Figure 8 (and also visible in Figs 3 and 7), the connectors 122a-c may advantageously comprise a narrowed, central portion 145 and widened, end portions 146, wherein at outer ends 147 of the connector 122a-c the widened end portion 146 has a horizontal length c1 which is equal to the horizontal length c2 (see Fig. 4) of the adjacent intersecting surface 118. In this manner, the connectors 122a-c can be structurally connected to the columns 106a-c similarly as the pontoon members 112a-c are, i.e. across the full length of the intersecting surface 118, while having a reduced cross-section in the central portion 145. This can provide beneficial load transfer between the ends 147 and the columns 106a-c while reducing weight and material use if the load capacity requirements of the connectors 122a-c can be satisfied with a reduced cross-section in the central portion 145.

Advantageously, the connectors 122a-c are arranged with a planar outward-facing vertical side 149 (see Fig. 8) between the ends 147, and wherein the reduction in the cross-section in the narrowed, central portion 145 is obtained by indentation at an inward-facing side of the connectors 122a-c, as also illustrated in Fig. 7. Particularly, the entire outward-facing vertical side 149 can be a single, straight planar surface.

Referring now to Figure 4 again, in each of the columns 106a-c the inner intermediate side 150 can be connected to two adjoining intersecting surfaces 118, the outer intermediate side 151 can be connected to two adjoining external sides 152,153, and each intersecting surface 118 can be connected to a respective external side 152,153 to form a hexagonal lateral cross-section of the column.

Advantageously, an angle v1 between the inner intermediate side 150 and the intersecting surfaces 118 can be made greater than an angle v2 between the outer intermediate side 151 and the external sides 152,153 so as to produce an irregular hexagon.

Each intersecting surface 118 can be connected to a respective external side 152,153 at an angle of 90 degrees.

Advantageously, the sum of the horizontal length of the inner intermediate side 150 and the intersecting surfaces 118 can be made less than the sum of the horizontal length of the outer intermediate side 151 and the external sides 152,153. Additionally or alternatively, the individual horizontal lengths of the inner intermediate side 150 and the intersecting surfaces 118 are less than the individual horizontal length of any of the outer intermediate side 151 and the external sides 152,153. (I.e. sides 151, 152 and 153 are all longer than sides 118 and 150.) Illustrated in Fig. 7, the outer intermediate side 151 may also form (or form part of) a planar edge surface 148 of the hull. By 'edge surface' here is meant a vertical surface arranged at the edge portions of the substantially triangular hull. While the hull may have such surfaces and therefore not form a perfect triangle, it is nevertheless substantially triangular in that the edge surfaces 148 are considerably shorter than the sides, for example less than one-fifth or less than one-tenth of the sides.

Advantageously, the planar edge surface 148 is a single planar surface extending across the full height of the hull. The planar edge surface 148 can be made up entirely of the outer intermediate side 151, if the columns 106a-c extend across the full height of the hull, or it can be made up partly of the pontoon members 112a-c and/or the connectors 122a-c if these components extend towards the edges and is fixed to the columns 106a-c above and/or below the columns 106a-c.

The hull may, about its horizontal periphery, comprise six, preferably exactly six, planar, vertical surfaces making up the outermost bounds of the hull in the horizontal plane. The six or exactly six surfaces can be defined by three planar side surfaces 149,152,153,154,155 and three planar edge surfaces 148.

The features according to Figs 4, 7 and 8 and the associated description provide, individually or collectively, advantages of enhanced structural strength and reliability combined with good manufacturability, in that, for example, internal strengthening of the hull is simplified and/or that the design is better suited to handle load hotspots such as the loads acting in the interfaces on the inner side of lateral axis 134. For example, providing an irregular polygon/hexagon which is skewed in relation to the lateral axis 134 (see Fig. 4) in a beneficial manner, can improve load handling capability of the floater.

The person skilled in the art realises that the present disclosure is not limited to the preferred embodiments described above. The person skilled in the art further realises that modifications and variations are possible within the scope of the appended claims.

Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed disclosure, from a study of the drawings, the disclosure, and the appended claims.

Claims

CLAIMS 1. 2. 3. 4. 5. 6. 7. 8.A floating wind turbine platform (104), comprising: a substantially triangular hull configurable to support a wind turbine tower; the hull comprising a first, second and third column (106a-c), the first, second and third columns (106a-c) being connected by a first, second and third pontoon member (112a-c), as well as by a first, second and third connector (122a-c).
The floating wind turbine platform (104) according to any preceding claim, wherein each of the first, second and third columns (106a-c) comprises two axially extending intersecting surfaces (118), each intersecting surface (118) being oriented perpendicular to the longitudinal axis of a pontoon member (112a-c).
The floating wind turbine platform (104) according to any preceding claim, wherein the lateral cross-section of each of the first, second and third columns (106a-c) has the shape of an irregular polygon.
The floating wind turbine platform (104) according to any preceding claim, wherein the lateral cross-section of each of the first, second and third columns (106a-c) has the shape of a hexagon.
The floating wind turbine platform (104) according to any preceding claim, wherein the lateral cross-section of each of the first, second and third columns (106a-c) has the shape of an irregular hexagon.
The floating wind turbine platform (104) according to any preceding claim, wherein an angle between two adjacent sides of the irregular hexagon is a right angle.
The floating wind turbine platform (104) according to any preceding claim, wherein each of the first, second and third columns (106a-c) connect to two of the first, second and third pontoon members (112a-c).
The floating wind turbine platform (104) according to any preceding claim, wherein each of the first, second and third columns (106a-c) comprises a first and a second intersecting surface (118), each of the first and second intersecting surfaces (118) connected to one of the two of the first, second and third pontoon members (112a-c).
9. The floating wind turbine platform (104) according to any preceding claim, wherein the first, second and third columns (106a-c) are connected by the first, second and third pontoon members (112a-c) in a triangular form.
10. The floating wind turbine platform (104) according to any preceding claim, wherein the first, second and third connectors (122a-c) are located above and parallel to the first second and third pontoon members (112a-c).
11. The floating wind turbine platform (104) according to any preceding claim, wherein each of the first, second and third columns (106a-c) comprises a first and a second intersecting surface (118) and each of the first and second intersecting surfaces (118) are connected to one of the two of the first, second and third connectors (122a-c).
12. The floating wind turbine platform (104) according to any preceding claim, wherein each of the first, second and third columns (106a-c) comprises an inner intermediate side (150) and an outer intermediate side (151), the inner and outer intermediate sides (150,151) being parallel to each other and perpendicular to an axis (132) extending between the centre of the lateral cross-section and the centre of the floating platform (104).
13. The floating wind turbine platform (104) according to any preceding claim, wherein the horizontal length (b1) of the inner intermediate side (150) is smaller than the horizontal length (b2) of the outer intermediate side (151) or wherein the horizontal length (b1) of the inner intermediate side (150) is equal to the horizontal length (b2) of the outer intermediate side (151)
14. The floating wind turbine platform (104) according to any preceding claim, wherein each of the first, second and third columns (106a-c) comprises a first external side (152) adjoining a first intersecting surface (118) and a second external side (153) adjoining a second intersecting surface (118).
15. The floating wind turbine platform (104) according to any preceding claim, wherein the first and second external sides (152,153) each are flush with an outer side (154,155) of a respective pontoon members (112a-c).
16. The floating wind turbine platform (104) according to any preceding claim, wherein the first and second external sides (152,153) each are flush with an outer side (149) of a respective connectors (122a-c).
17. The floating wind turbine platform (104) according to any preceding claim, wherein, on each of the three sides of the substantially triangular hull, the respective external side (152,153) of the column (106a-c), the outer side (154,155) of the pontoon member (112a-c) and the outer side (149) of the connector (122a-c) are coplanar, particularly wherein the external side (152,153) of the column (106a-c), the outer side (154,155) of the pontoon member (112a-c) and the outer side (149) of the connector (122a-c) make up a single, planar surface.
18. The floating wind turbine platform (104) according to any preceding claim, wherein each connector (122a-c) comprises a narrowed, central portion (145) and widened, end portions (146), wherein at outer ends (147) of the connector (122a-c) the widened end portion (146) has a horizontal length (cl) equal to the horizontal length (c2) of the adjacent intersecting surface (118).
19. The floating wind turbine platform (104) according to any preceding claim, wherein the connectors (122a-c) between the ends (147) has a planar outward-facing vertical side (149), particularly wherein the entire outward-facing vertical side (149) is a single planar surface.
20. The floating wind turbine platform (104) according to any preceding claim, wherein in each column (106a-c) an inner intermediate side (150) is connected to two adjoining intersecting surfaces (118), an outer intermediate side (151) is connected to two adjoining external sides (152,153), and each intersecting surface (118) is connected to a respective external side (152,153) to form a hexagonal lateral cross-section of the column.
21. The floating wind turbine platform (104) according to the preceding claim, wherein an angle (v1) between the inner intermediate side (150) and the intersecting surfaces (118) is greater than an angle (v2) between the outer intermediate side (151) and the external sides (152,153) so as to produce an irregular hexagon.
22. The floating wind turbine platform (104) according to any preceding claim, wherein each intersecting surface (118) is connected to a respective external side (152,153) at an angle of 90 degrees.
23. The floating wind turbine platform (104) according to any preceding claim, wherein the sum of the horizontal length of the inner intermediate side (150) and the intersecting surfaces (118) is less than the sum of the horizontal length of the outer intermediate side (151) and the external sides (152,153).
24. The floating wind turbine platform (104) according to any preceding claim, wherein the individual horizontal lengths of the inner intermediate side (150) and the intersecting surfaces (118) are less than the individual horizontal length of any of the outer intermediate side (151) and the external sides (152,153).
25. The floating wind turbine platform (104) according to any preceding claim, wherein the outer intermediate side (151) forms or forms part of a planar edge surface (148).
26. The floating wind turbine platform (104) according to the preceding claim, wherein the planar edge surface (148) is a single planar surface extending across the full height of the hull.
27. The floating wind turbine platform (104) according to any preceding claim, wherein about its horizontal periphery, the hull comprises six, preferably exactly six, planar, vertical surfaces making up the outermost bounds of the hull, the six or exactly six surfaces being defined by three planar side surfaces (149,152,153,154,155) and three planar edge surfaces (148).
28. The floating wind turbine platform (104) according to any preceding claim, wherein at least one of the first, second and third pontoon members (112a-c) comprises a ballast arrangement (124).
29. The floating wind turbine platform (104) according to any preceding claim, wherein the ballast arrangement (124) comprises a ballast compartment extending along substantially the entire length of one of the first, second and third pontoon members (112a-c).
30. The floating wind turbine platform (104) according to any preceding claim, wherein the ballast arrangement (124) comprises a ballast compartment extending partially along the length of at least one of the first, second and third pontoon members (112a-c).
31. The floating wind turbine platform (104) according to any preceding claim, wherein the ballast arrangement (124) comprises a ballast compartment extending along substantially one half of two of the first, second and third pontoon members (112a-c).
32. The floating wind turbine platform (104) according to any preceding claim, wherein the wind turbine tower is configurable mounted to one of the first, second and third columns (106a-c), and the first, second and third columns (106a-c) are connected by the first, second and third pontoon members (112a-c) in a triangular form, such that the ballast arrangement (124) comprises a ballast compartment extending along substantially the entire length of a pontoon member (112a-c) located opposite the one of the first, second and third columns (106a-c) to which the turbine tower is configurable to be mounted.
33. The floating wind turbine platform (104) according to any preceding claim, wherein the ballast arrangement (124) comprises a ballast compartment extending along substantially one half of each of the first, second and third pontoon members (112a-c) that are located adjacent the one of the first, second and third columns (106a-c) to which the turbine tower is configurable to be mounted.