Wind power generation equipment

Abstract

This design suppresses the tilting motion of wind turbines caused by waves, thereby reducing the decrease in power generation efficiency. [Solution] The wind power generation equipment comprises a floating body and a wind power generation device having a wind turbine mounted on the floating body, the floating body comprising a first column that supports the wind turbine and has a first hollow section, a plurality of second columns that are arranged symmetrically with respect to an imaginary line extending horizontally through the first column when viewed from above and each having a second hollow section, a first connecting member that connects the first column and the plurality of second columns, and a projection that, when viewed from above, protrudes from the second column in a direction away from the first column in the direction in which the first connecting member extends.

Description

Technical Field

[0005] , ,

[0004] , , ,

[0001] The present disclosure relates to wind power generation equipment.

Background Art

[0002] Patent Document 1 discloses a floating windmill including a floating body that generates buoyancy to float on the ocean, and a wind power generation device installed on the floating body. In this floating windmill, the floating body includes a single first column on which the wind power generation device is installed, two second columns, and a lower hull that connects between the first column part and the two second column parts, respectively.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, the buoyancy of the floating body described above acts on the volume center of the submerged part of the floating body (hereinafter referred to as the center of buoyancy). When the horizontal position of the center of gravity and the horizontal position of the center of buoyancy in the floating body do not match, a moment around the center of gravity is generated by the buoyancy and the floating body tilts. Therefore, in a general floating body, the distribution of the displaced volume of the floating body and the distribution of the ballast in the floating body are set to make the horizontal position of the center of buoyancy and the horizontal position of the center of gravity coincide. In a floating body such as that of Patent Document 1, the weight of the wind power generation device installed on the first column is large and the position of the center of gravity is close to the first column. Therefore, also in a floating body such as that of this Patent Document 1, the displaced volume of the floating body and the distribution of the ballast are set to make the horizontal position of the center of buoyancy and the horizontal position of the center of gravity coincide.

[0005] On the other hand, the increase or decrease in buoyancy when the floating body is displaced vertically acts on the centroid of the volume of the increased or decreased portion of the submerged area. Since this increased or decreased volume is equal to the area of ​​the waterline (in other words, the cross-section of the floating body that crosses the water surface) multiplied by the vertical displacement of the floating body, the horizontal position on which the increase or decrease in buoyancy acts is the centroid of the waterline of the floating body (hereinafter referred to as the center of the floating surface). For example, if the horizontal position of the floating surface center of a floating body differs from the horizontal position of the floating body's center of gravity and center of gravity, the increase or decrease in buoyancy due to vertical movement acts on the position of the floating surface center, generating a moment around the center of gravity, causing the floating body and the wind turbine on it to tilt.

[0006] Furthermore, in floating structures like the one described in Patent Document 1, the design is often such that the natural period of the motion in the direction of tilting in the longitudinal direction (hereinafter referred to as pitch) is detuned from the wave period band. However, if the horizontal position of the floating surface center of the floating structure differs from the horizontal position of the center of gravity and the center of gravity of the floating structure, a moment is generated around the center of gravity due to the increase or decrease in buoyancy, and pitch motion is induced by vertical motion (hereinafter referred to as heave), which is closer to the wave period band, potentially causing the wind turbine to tilt. When a wind turbine tilts, the angle of the turbine relative to the wind changes, which reduces the power generation efficiency of the wind power generation system.

[0007] This disclosure was made to solve the above-mentioned problems and aims to provide a wind power generation system that can suppress the swaying of the wind turbine in the direction of tilting due to the influence of waves, thereby suppressing the decrease in power generation efficiency. [Means for solving the problem]

[0008] To solve the above problems, a wind power generation facility according to one embodiment of the present disclosure comprises a floating body and a wind power generation device having a wind turbine provided on the floating body, wherein the floating body comprises a first column that supports the wind turbine and has a first hollow portion, a plurality of second columns provided symmetrically with respect to an imaginary line that passes through the first column and extends horizontally when viewed from above, and each having a second hollow portion, a plurality of first connecting members located below the water surface and connecting the first column and the second column, and a projection that protrudes from the second column in a direction away from the first column in the direction in which the first connecting members extend.

[0009] Another embodiment of the wind power generation equipment relating to the present disclosure comprises a floating body and a wind power generation device having a wind turbine provided on the floating body, wherein the floating body comprises a first column that supports the wind turbine and has a first hollow section, a plurality of second columns that are provided symmetrically with respect to an imaginary line that passes through the first column and extends horizontally when viewed from above, and each has a second hollow section, a plurality of first connecting members located below the water surface and connecting the first column and the second column, and struts located below the water surface that connect the first connecting members to each other and have greater buoyancy than the first connecting members. [Effects of the Invention]

[0010] According to the wind power generation equipment disclosed herein, it is possible to suppress the swaying of the wind turbine in the direction that causes it to tilt due to the effects of waves, thereby suppressing the decrease in power generation efficiency. [Brief explanation of the drawing]

[0011] [Figure 1] This is a side view of a wind power generation facility according to the first embodiment of this disclosure. [Figure 2] This is a view from above of the floating structure of a wind power generation facility in the first embodiment of the present disclosure. [Figure 3] This is a flowchart showing the procedure for the design method of a wind power generation facility according to the first embodiment of this disclosure. [Figure 4] This figure shows the response coefficient of a wind turbine in regular waves, which is affected by the difference in the dimensional difference between the center of buoyancy (center of gravity) of the wind turbine and the center of the floating surface of the floating body. [Figure 5] This is a view from above of the floating structure of a wind power generation facility in the second embodiment of the present disclosure. [Modes for carrying out the invention]

[0012] The wind power generation equipment and the design method for the wind power generation equipment according to the embodiments of this disclosure will be described below with reference to Figures 1 to 5. <First Embodiment> (Overall configuration of wind power generation equipment) Figure 1 is a side view of a wind power generation facility according to the first embodiment of this disclosure. As shown in Figure 1, the wind power generation facility 1 of this first embodiment comprises a floating body 2 that floats on the water surface F and a wind power generation device 3.

[0013] The wind power generation device 3 is installed on the floating body 2. The wind power generation device 3 is installed on the first column 21, which will be described later, on the floating body 2. The wind power generation device 3 comprises at least a wind turbine 32 and a generator (not shown). The wind turbine 32 comprises a tower 33, a nacelle 34, and a rotor 35.

[0014] The tower 33 is formed in a columnar shape extending upward from the first column 21 of the floating body 2. The nacelle 34 is provided at the upper end of the tower 33. The nacelle 34 is rotatably mounted on the tower 33 via bearings (not shown) around an axis C1 extending in the vertical direction.

[0015] The rotor 35 has a hub 35a and a plurality of blades 35b. The hub 35a is mounted on the nacelle 34 so as to be rotatable around an axis C2 that intersects it in the vertical direction. Multiple blades 35b are provided on the hub 35a at circumferential intervals around the axis C2. Each blade 35b extends radially outward from the hub 35a around the axis C2.

[0016] The rotor 35 rotates in the circumferential direction around the axis C2 as the plurality of blades 35b receive wind. A generator (not shown) is connected to the hub 35a via, for example, a speed increaser (not shown). The generator and the speed increaser are housed, for example, in the nacelle 34.

[0017] In the wind power generation device 3, as the rotor 35 rotates by receiving wind, the generator is driven to generate electricity. Further, the rotor 35 generates electricity efficiently as the nacelle 34 rotates around the axis C1 according to the direction of the wind.

[0018] FIG. 2 is a view of the floating body of the wind power generation facility in the first embodiment of the present disclosure as seen from above. As shown in FIGS. 1 and 2, the floating body 2 includes a first column 21, a plurality of second columns 22A and 22B, a connecting member 25, a protruding portion 26, a first ballast 27, and a second ballast 28. In the first embodiment, the floating body 2 includes one first column 21 and two second columns 22A and 22B.

[0019] As shown in FIG. 1, the first column 21 has a cylindrical portion 21a, an upper plate portion 21t, and a lower plate portion 21d. The first column 21 in the first embodiment is formed in a circular shape when viewed from above. The cylindrical portion 21a is formed in a cylindrical shape extending in the vertical direction. The upper plate portion 21t closes the opening at the upper end of the cylindrical portion 21a. The lower plate portion 21d closes the opening at the lower end of the cylindrical portion 21a. Such a first column 21 is hollow, and a first hollow portion 21s filled with gas (air) is formed inside. A tower 33 of the windmill 32 is provided on the upper plate portion 21t of the first column 21. That is, the first column 21 supports the windmill 32.

[0020] As shown in Figure 2, the two second columns 22A and 22B are arranged symmetrically with respect to a virtual line X that passes through the center 21c of the first column 21 and extends horizontally when viewed from above. In the first embodiment, the spacing between the first column 21 and each of the two second columns 22A and 22B is exemplified as being equal to the spacing between the two second columns 22A and 22B. However, the spacing between the first column 21 and each of the two second columns 22A and 22B does not have to be equal to the spacing between the two second columns 22A and 22B. In that case, the floating body 2 will have an isosceles triangle shape when viewed from above.

[0021] As shown in Figure 1, each second column 22A, 22B has a cylindrical portion 22a, an upper plate portion 22t, and a lower plate portion 22d. In the first embodiment, the second columns 22A, 22B are formed in a circular shape when viewed from above. The cylindrical portion 22a is formed in a cylindrical shape that extends in the vertical direction. The upper plate portion 22t closes the opening at the upper end of the cylindrical portion 22a. The lower plate portion 22d closes the opening at the lower end of the cylindrical portion 22a. Such second columns 22A, 22B are hollow and have a second hollow portion 22s in which gas (air) is sealed inside.

[0022] The first column 21 and the two second columns 22A and 22B have the same height in the vertical direction.

[0023] Here, as shown in Figure 2, the cross-sectional area A1 of the first column 21 when viewed from above is the same as the cross-sectional area A2 of the second columns 22A and 22B when viewed from above. Note that the cross-sectional area A1 may be larger than the cross-sectional area A2. By making the cross-sectional area A1 larger than the cross-sectional area A2, when the first column 21 and the second column 22A are submerged by the same amount below the water surface F, the buoyancy force F1 acting on the first column 21 is greater than the buoyancy force F2 acting on the second column 22A (F1>F2). Similarly, when the first column 21 and the second column 22B are submerged by the same amount below the water surface F, the buoyancy force F1 acting on the first column 21 is greater than the buoyancy force F2 acting on the second column 22B (F1>F2).

[0024] As shown in Figures 1 and 2, the connecting member 25 connects the first column 21 and a plurality of second columns 22A and 22B. The connecting member 25 in the first embodiment includes a first connecting member 25A that connects the first column 21 to one of the second columns 22A, a first connecting member 25B that connects the first column 21 to the other second column 22B, and a second connecting member 25C that connects the two second columns 22A and 22B to each other.

[0025] The first connecting members 25A, 25B, and the second connecting member 25C all extend in a direction intersecting the vertical direction below the water surface F. Here, the horizontal direction can be exemplified as the direction intersecting the vertical direction. In the first embodiment, the first connecting member 25A connects the lower end of the first column 21 to the lower end of one of the second columns 22A. Similarly, the first connecting member 25B connects the lower end of the first column 21 to the lower end of the other second column 22B. Furthermore, the second connecting member 25C connects the lower end of one of the second columns 22A to the other second column 22B.

[0026] The first connecting members 25A, 25B, and the second connecting member 25C, as illustrated in the first embodiment, have the same and constant height H1 (see Figure 1) in the vertical direction. Furthermore, the width dimension Wa of the first connecting members 25A and 25B, as illustrated in the first embodiment, is greater than the width dimension Wb of the second connecting member 25C. Here, the width dimension Wa of the first connecting members 25A and 25B and the width dimension Wb of the second connecting member 25C are dimensions in a direction that intersects both the vertical direction and their respective extension directions. In addition, the heights of the first connecting members 25A, 25B, and the second connecting member 25C, as illustrated in the first embodiment, are smaller than their width dimensions.

[0027] The connecting members 25 (25A, 25B, 25C) of the first embodiment are hollow and have a hollow portion 25c in which gas (air) is sealed inside. As a result, buoyancy is generated in the connecting members 25 that are submerged below the water surface F, which can contribute to increasing the buoyancy of the floating body 2.

[0028] The first ballast 27 is provided within the first hollow section 21s. The second ballast 28 is provided within the second hollow sections 22s of each of the two second columns 22A and 22B. The first ballast 27 and the second ballast 28 are, for example, seawater. The first ballast 27 and the second ballast 28 may also be, for example, sand, powdered metal, block-shaped metal, etc. Other ballast (not shown) may be provided within the first connecting members 25A and 25B or within the protruding section 26.

[0029] (protrusion) When viewed from above, the protruding portion 26 protrudes from the second columns 22A and 22B in the direction away from the first column 21, in the direction of extension of the first connecting members 25A and 25B. In the first embodiment, the protruding portion 26 includes a protruding portion 26A that extends from the second column 22A so as to extend the first connecting member 25A away from the first column 21, and a protruding portion 26B that extends from the second column 22A so as to extend the first connecting member 25B. The protruding portions 26A and 26B have hollow portions 26c formed in the same way as the hollow portions 25c of the first connecting members 25A and 25B. In the first embodiment, the height and width dimensions of the protruding portion 26 are the same as the first connecting members 25A and 25B, with height H1 and width Wa. However, the height and width dimensions of the protruding portion 26 are not limited to the same height H1 and width Wa as the first connecting members 25A and 25B.

[0030] (Position of the center of buoyancy) As shown in Figure 2, in the wind power generation facility 1, the distance Xc from the center 21c of the first column 21 to the center of the floating surface Pm of the floating body 2, on a virtual line X passing through the center 21c of the first column 21 when viewed from above, is expressed by the following equation (1). The center of the floating surface Pm coincides with the centroid of the cross-section (in other words, the waterline plane) where the floating body 2 crosses the water surface F, which is the still water surface. Note that the center 21c can also be said to be the centroid of the cross-section where the first column 21 crosses the water surface F. Xc = (At - A1) × Xa / At …(1) Here, At is the sum of the cross-sectional area A1 of the first column 21 when viewed from above, the cross-sectional area A2 of one of the second columns 22A when viewed from above, and the cross-sectional area A2 of the other second column 22B when viewed from above, as shown in equation (2). At = A1 + A2 + A2 …(2) Furthermore, Xa is the distance from the center 21c of line K, which connects the center 22Ac of one second column 22A to the center 22Bc of the other second column 22B, on the imaginary line X. Note that the center 22Ac can also be said to be the centroid of the cross-section where the second column 22B crosses the water surface F.

[0031] (Location of the center of gravity of wind power generation equipment) In this embodiment, the center of gravity Gm of the entire wind power generation facility 1, which combines the floating body 2 and the wind power generation device 3 installed on the first column 21, is shown to be located on the imaginary line X, closer to the first column 21 than to the center of buoyancy Pm. The horizontal position of the center of gravity Gm of the entire wind power generation facility 1 is designed and adjusted to coincide with the horizontal position of the center of buoyancy Fm, which is the center of the total volume of the floating body 2 that is submerged below the still water surface F.

[0032] (Floating surface) For example, when the floating body 2 is displaced vertically, a change occurs in the drainage volume of the first column 21. The amount by which the drainage volume of the first column 21 changes is equivalent to the value obtained by multiplying the area of ​​the waterline surface of the first column 21 (in other words, the waterline area) by the length of the vertical displacement. The amount by which the drainage volume of the first column 21 changes multiplied by the weight of the surrounding seawater gives the increase or decrease in buoyancy F1 of the first column 21 (see Figure 1). Similarly, in the second columns 22A and 22B, an increase or decrease in buoyancy F2 occurs due to the change in drainage volume (see Figure 1). The center of the buoyancy surface Pm is the point where the increase or decrease in buoyancy F1 occurring in the first column 21 and the increase or decrease in buoyancy F2 occurring in the two second columns 22A and 22B meet. In the first embodiment of the wind power generation equipment 1, the center of buoyancy Pm of the floating body 2 is positioned to be close to the center of gravity Gm and the center of buoyancy Fm of the wind power generation equipment 1, which is the combination of the floating body 2 and the wind power generation device 3.

[0033] In the floating structure 2, the cross-sectional area A1 of the first column 21 and the cross-sectional area A2 of the second columns 22A and 22B are the same (A1=A2). However, the horizontal position of the center of action of the buoyancy of the first connecting members 25A and 25B that connect the first column 21 and the second columns 22A and 22B is located closer to the first column 21 than the horizontal position of the center of buoyancy Pm of the floating structure 2. Therefore, the horizontal position of the center of buoyancy Fm of the floating structure 2 is also located closer to the first column 21 than the center of buoyancy Pm. As described above, in order to prevent the wind power generation equipment 1 from tilting in a stationary state, the distribution of ballast weight is set so that the horizontal position of the center of buoyancy Fm of the floating structure 2 coincides with the horizontal position of the center of gravity Gm of the entire wind power generation equipment 1. Therefore, similar to the center of buoyancy Fm, the center of gravity Gm of the entire wind power generation equipment 1 is also located closer to the first column 21 than the center of buoyancy Pm.

[0034] For example, suppose the center of gravity Gm of the entire wind power generation facility 1 is located on the imaginary line X, and is closer to the first column 21 than the center of the floating surface Pm of the floating body 2, by a distance L. Then, when the entire wind power generation facility 1 is displaced vertically by ΔZg, a rotational moment M is generated, corresponding to the increase or decrease in buoyancy due to the change in the drainage volume of the floating body 2, and the distance L that the center of gravity Gm is separated from the center of the floating surface Pm1. The rotational moment M is expressed by the following equation (3). M = ΔFz × L …(3) Here, ΔFz = ρ × g × At × ΔZg Here, ρ is the density of seawater, g is the acceleration due to gravity, At is the waterline area, and ΔZg is the vertical displacement of the entire wind power generation facility 1. ρ × g can also be expressed as the weight per unit volume of seawater, and At × ΔZg as the change in the volume of wastewater.

[0035] When the floating body 2 moves vertically (heave direction) due to waves generated in the sea on which the wind power generation equipment 1 is floating, the rotational moment M induces pitch motion in the wind power generation equipment 1 around an axis that intersects the imaginary line X in the horizontal plane. This phenomenon, in which pitch motion is induced along with heave motion of the floating body 2, is called a pitch-heave coupled mode. In wind power generation equipment 1, if the natural period of the heave motion is shorter than the pitch motion, even if the natural period of the pitch motion is sufficiently detuned from the wave period band, there is a concern that if the natural period of the heave motion is close to the wave period band, the pitch-heave coupled mode may induce pitch motion in wind power generation equipment 1.

[0036] (Consideration of the configuration of the first embodiment) In contrast, as shown in Figures 1 and 2, the wind power generation equipment 1 of the first embodiment is provided with a protrusion 26 on the floating body 2. In this way, the buoyancy of the protrusion 26 increases in proportion to the length of the protrusion 26 that protrudes from the second columns 22A and 22B on the opposite side from the first column 21. As a result, the horizontal position of the center of buoyancy Fm approaches the horizontal position of the center of buoyancy Pm. Consequently, the center of buoyancy Fm of the floating body 2 in the first embodiment is closer to the center of buoyancy Pm than it would be if the floating body 26 were not present.

[0037] In other words, the distance L at which the center of buoyancy Fm of the floating body 2 is separated from the center of the floating surface Pm on the imaginary line X toward the first column 21 becomes smaller. Therefore, the rotational moment M (M = ΔFz × L) generated in the wind power generation equipment 1 according to the distance L at which the center of buoyancy Fm is separated from the center of the floating surface Pm becomes smaller than the rotational moment M when the protrusion 26 is not provided. It is more preferable that the horizontal position of the center of buoyancy Fm coincides with the horizontal position of the center of the floating surface Pm.

[0038] As a result, when the floating body 2 moves vertically (heave direction) due to waves generated in the sea on which the wind power generation equipment 1 is floating, the pitch motion induced in the wind power generation equipment 1 by the rotational moment M is suppressed. Consequently, by suppressing the pitch motion of the wind power generation equipment 1 due to the pitch-heave coupled mode, the displacement of the wind turbine 32 in the direction of tilting is suppressed, and the stability of the wind power generation equipment 1 is increased.

[0039] (Procedure for designing wind power generation equipment) Figure 3 is a flowchart showing the steps of a wind power generation equipment design method according to the first embodiment of this disclosure. As shown in Figure 3, the wind power generation equipment design method S10 according to the first embodiment of this disclosure includes a step S11 for setting the shape of the floating body and a step S12 for setting the weight distribution of the floating body. In step S11, which sets the shape of the floating body, as shown in Figure 2, the horizontal position of the center of buoyancy Fm, which is the volume center of the submerged portion of the floating body 2, and the position of the center of buoyancy plane Pm, which is the centroid of the waterline area of ​​the floating body 2 are determined. Then, the shape of the cross-section where the first column 21 and the second columns 22A and 22B cross the water surface, and the distribution of the drainage volume of the submerged portion of the floating body where the first column 21 and the second columns 22A and 22B are submerged in water are set so that the horizontal position of the center of buoyancy Pm and the center of buoyancy Fm coincide.

[0040] In step S12, which sets the weight distribution of the floating body, the weight distribution of the ballast inside the floating body 2 (first ballast 27, second ballast 28) and the overall equipment arrangement of the wind power generation equipment 1 is set so that the horizontal position of the center of buoyancy Fm, which is determined by the drainage volume distribution of the submerged part of the floating body set in step S11, coincides with the horizontal position of the center of gravity of the floating body 2. For example, in step S12, which sets the weight distribution of the floating body, the weights W2 of the two second ballasts 28 and the weight W1 of the first ballast 27 are set so that the position of the center of gravity of the floating body 2 coincides with the center of buoyancy Fm. In other words, in step S12, the weight distribution of at least two second ballasts 28 and first ballasts 27 is set so that the position of the center of gravity Gm coincides with the center of buoyancy Fm. Note that other ballasts (not shown) mentioned above may also be included in the setting of the weight distribution. Furthermore, in step S12 of setting the weight distribution of the floating body in this embodiment, the shape of the protrusion 26 is determined such that the horizontal position of the center of buoyancy Fm of the floating body 2 moves away from the first column 21 and approaches the horizontal position of the center of buoyancy Pm. In other words, the buoyancy of the protrusion 26 is set. Furthermore, the weight distribution of the weight W1 of the first ballast 27 and the weight W2 of the two second ballasts 28 is preferably set, in conjunction with the weight distribution due to the arrangement of equipment throughout the entire facility, such that, for example, the center of buoyancy Fm and the center of gravity Gm are located within, for example, 3 m in the horizontal plane relative to the center of buoyancy Pm.

[0041] Figure 4 shows the response coefficient of a wind power generation facility in regular waves, which is affected by the difference in the horizontal distance between the center of buoyancy (center of gravity) of the wind power generation facility and the center of the floating surface of the floating body. Figure 4 shows the response coefficient in a regular wave for the wind power generation facility 1 described above, when the distance L between the floating surface center Pm and the floating center Fm is set to L=5m, L=3m, L=1m, and L=0m (the centroid Gm and floating center Fm coincide). The response coefficient in a regular wave shows the correlation between the dimensionless wave period (wave period / natural period of the floating body's heap) and the displacement angle in the pitch direction of the wind power generation facility 1 per unit wave height. As shown in Figure 4, the smaller the distance L between the center of buoyancy Pm and the center of buoyancy Fm, the more the pitch-direction motion of the wind power generation equipment 1 is suppressed.

[0042] (Effects and Benefits) In the wind power generation equipment 1 of the first embodiment described above, the first connecting members 25A and 25B that connect the first column 21 and the second columns 22A and 22B are provided with protruding portions 26 that extend in the direction away from the first column 21 from the second columns 22A and 22B in the direction of extension. Therefore, the buoyancy obtained by the protruding portions 26 can bring the horizontal position of the center of buoyancy Fm closer to the horizontal position of the center of buoyancy Pm, thereby reducing the rotational moment M that occurs with heave motion. Consequently, the oscillation of the wind power generation equipment 1 in the direction in which the wind turbine 32 tilts due to the influence of waves can be suppressed, and the decrease in power generation efficiency caused by oscillation in the direction in which the wind turbine 32 tilts can be suppressed.

[0043] Furthermore, in the first embodiment described above, the first hollow section 21s of the first column 21 supporting the wind turbine 32 is provided with a first ballast 27, and each of the second hollow sections 22s of the multiple second columns 22 is provided with a second ballast 28. This makes it possible to fine-tune the horizontal position of the center of buoyancy Fm by combining the weight distribution of the first ballast 27 and the second ballast 28 with fine-tuning of the external shape of the submerged part of the floating body.

[0044] Furthermore, in the first embodiment described above, the connecting member 25 and the protruding portion 26 each have hollow portions 25c and 26c, respectively. This increases the buoyancy of the protruding portion 26. In addition, since the connecting member 25 also generates buoyancy, the buoyancy of the entire floating body 2 can be increased.

[0045] Furthermore, in the design method for the wind power generation equipment of the first embodiment described above, the shape of the floating body is set and the weight distribution of the floating body 2 is set so that the horizontal position of the center of buoyancy Fm coincides with the horizontal position of the center of buoyancy Pm. Therefore, the oscillation of the wind power generation equipment 1 in the direction in which the wind turbine 32 tilts due to the influence of waves is suppressed, and the decrease in power generation efficiency caused by oscillation in the direction in which the wind turbine 32 tilts can be suppressed.

[0046] <Second Embodiment> Next, a second embodiment of this disclosure will be described with reference to the drawings. This second embodiment differs from the first embodiment in that the buoyancy center is brought closer to the buoyancy center by modifying the configuration of the second connecting member instead of the protruding portion. For this reason, the same reference numerals are used for the same parts as in the first embodiment, and redundant explanations are omitted.

[0047] Figure 5 is a view from above of the floating structure of a wind power generation facility in the second embodiment of this disclosure. As shown in Figure 5, the wind power generation facility 1B of the second embodiment comprises a floating body 2B that floats on the water surface F, and a wind power generation device 3 (see Figure 1). The floating body 2B comprises a first column 21, a plurality of second columns 22A, 22B, a connecting member 25, a first ballast 27, a second ballast 28, and a strut 29. The floating body 2B of the second embodiment comprises one first column 21 and two second columns 22A, 22B, similar to the first embodiment. The first column 21 is hollow and has a first hollow section 21s formed inside it, which is filled with gas (air). Similarly, the second columns 22A, 22B are hollow and have a second hollow section 22s filled with gas (air).

[0048] The connecting member 25 connects the first column 21 and a plurality of second columns 22A, 22B. In the second embodiment, the connecting member 25 includes a first connecting member 25A that connects the first column 21 to one of the second columns 22A, and a first connecting member 25B that connects the first column 21 to the other second column 22B.

[0049] The strut 29 is formed in the floating body 2B of the wind power generation equipment 1B, extending between a first connecting member 25A that connects the first column 21 to one of the second columns 22A, and a first connecting member 25B that connects the first column 21 to the other second column 22B.

[0050] The strut 29 extends in a direction intersecting the imaginary line X in the horizontal plane. The strut 29 is positioned closer to the second columns 22A and 22B than to the first column 21 in the direction in which the imaginary line X extends. In this second embodiment, the width dimension Wb of the strut 29 in the direction in which the imaginary line X extends in the horizontal plane is greater than the width dimension Wa of the connecting member 25C and the first connecting members 25A and 25B in the first embodiment. The strut 29 is hollow and has a hollow portion 29c filled with gas (air). As a result, the buoyancy of the strut 29 is greater than that of the first connecting member 25A (25B). Note that it is sufficient for the buoyancy of the strut 29 to be greater than that of the first connecting members 25A and 25B, and the width dimension Wb of the strut 29 is not limited to being greater than the width dimension Wa of the first connecting members 25A and 25B. Furthermore, the weight of the strut 29 may be greater than the weight of the first connecting member 25A (25B). Also, other ballast may be provided within the strut 29, similar to the first connecting members 25A, 25B and the protruding portion 26 of the first embodiment, and used to set the weight distribution as described above.

[0051] According to the second embodiment described above, by providing the strut 29, the horizontal position of the center of gravity Gm of the entire wind power generation equipment 1 and the horizontal position of the center of buoyancy Fm of the floating body 2 can be brought closer to the center of buoyancy Pm on the imaginary line X. Therefore, the oscillation of the wind power generation equipment 1 in the direction in which the wind turbine 32 would tip over can be suppressed.

[0052] (Other embodiments) Although embodiments of this disclosure have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and may include design changes and the like that do not depart from the gist of this disclosure. In the first embodiment, the case in which the first connecting members 25A and 25B and the second connecting member 25C are included was described, but the second connecting member 25C may be omitted. Furthermore, the configuration of the second embodiment may be combined with the first embodiment described above. Specifically, the floating body may be configured to further include both a protruding portion 26 and a strut 29, in addition to a first column 21, a second column 22, and first connecting members 25A and 25B. When both the protruding portion 26 and the strut 29 are provided, the second connecting member 25C may be omitted, or both the second connecting member 25C and the strut 29 may be provided.

[0053] In the first and second embodiments described above, the first column 21 and the second columns 22A and 22B are circular when viewed from above, but the design is not limited to this. For example, the first column 21 and the second columns 22A and 22B may be rectangular when viewed from above. By making them rectangular in this way, the drag coefficient in the long-period region increases. As a result, the response of the floating body 2, including the wind response, can be reduced, and the oscillation of the wind power generation equipment 1 in the direction in which the wind turbine 32 tilts can be suppressed more effectively.

[0054] <Note> The wind power generation equipment 1 and 1B described in each embodiment can be understood, for example, as follows.

[0055] (1) The first embodiment of the wind power generation equipment 1, 1B comprises floating bodies 2, 2B and a wind power generation device 3 equipped with a wind turbine 32 provided on the floating bodies 2, 2B, wherein the floating bodies 2, 2B include a first column 21 that supports the wind turbine 32 and has a first hollow portion 21s, a plurality of second columns 22 that are provided symmetrically with respect to an imaginary line extending horizontally through the first column 21 when viewed from above and each having a second hollow portion 22s, first connecting members 25A, 25B that connect the first column 21 and the plurality of second columns 22, and protruding portions 26 that project from the second column 22 in a direction away from the first column 21 in the direction in which the first connecting members 25A, 25B extend when viewed from above.

[0056] As a result, the buoyancy provided by the protrusion 26 brings the horizontal position of the center of buoyancy Fm closer to the horizontal position of the center of buoyancy Pm, thereby reducing the rotational moment M generated by the heave motion. Therefore, the oscillation of the wind power generation equipment 1 in the direction in which the wind turbine 32 tilts due to the influence of waves is suppressed, and the decrease in power generation efficiency caused by oscillation in the direction in which the wind turbine 32 tilts is suppressed.

[0057] (2) The wind power generation equipment 1, 1B according to the second embodiment is the wind power generation equipment 1, 1B of (1), comprising a first ballast 27 provided in the first hollow section 21s and a second ballast 28 provided in each of the second hollow sections 22s.

[0058] This makes it possible to fine-tune the horizontal position of the center of buoyancy Fm by combining the weight distribution of the first ballast 27 and the second ballast 28 with fine-tuning the external shape of the submerged part of the floating body.

[0059] (3) The wind power generation equipment 1, 1B according to the third embodiment is the wind power generation equipment 1, 1B of (1), wherein the first connecting members 25A, 25B and the protruding parts 26, 26A, 26B each have hollow parts 25c, 26c.

[0060] This increases the buoyancy of the protrusions 26, 26A, and 26B. Furthermore, since the connecting member 25 also generates buoyancy, the overall buoyancy of the floating bodies 2 and 2B can be increased.

[0061] (4) The wind power generation equipment 1, 1B according to the fourth embodiment is the wind power generation equipment 1, 1B of (3), wherein at least one of the first connecting members 25A, 25B and the protruding parts 26, 26A, 26B is equipped with other ballast.

[0062] This allows us to set the weight distribution of floating body 2, including other ballast.

[0063] (5) The wind power generation equipment 1, 1B according to the fifth embodiment is the wind power generation equipment 1, 1B of (1), which is located below the water surface and connects the first connecting members 25A, 25B to each other, and further comprises struts 29 which have greater buoyancy than the first connecting members 25A, 25B.

[0064] This allows the horizontal position of the center of gravity Gm of the entire wind power generation equipment 1 and 1B, and the horizontal position of the center of buoyancy Fm of the floating bodies 2 and 2B, to be brought closer to the center of buoyancy Pm on the imaginary line X. Therefore, the oscillation of the wind power generation equipment 1 and 1B in the direction that would cause the wind turbine 32 to tip over can be suppressed.

[0065] (6) The wind power generation equipment 1, 1B according to the sixth embodiment comprises floating bodies 2, 2B and a wind power generation device 3 equipped with a wind turbine 32 provided on the floating bodies 2, 2B, wherein the floating bodies 2, 2B comprise a first column 21 that supports the wind turbine 32 and has a first hollow portion 21s, a plurality of second columns 22 that are provided symmetrically with respect to an imaginary line that passes through the first column 21 and extends horizontally when viewed from above, and each has a second hollow portion 22s, first connecting members 25A, 25B that connect the first column 21 and the plurality of second columns 22, and struts that are located below the water surface, connect the first connecting members 25A, 25B to each other, and have greater buoyancy than the first connecting members 25A, 25B.

[0066] This allows the horizontal position of the center of gravity Gm of the entire wind power generation equipment 1 and 1B, and the horizontal position of the center of buoyancy Fm of the floating bodies 2 and 2B, to be brought closer to the center of buoyancy Pm on the imaginary line X. Therefore, the oscillation of the wind power generation equipment 1 and 1B in the direction that would cause the wind turbine 32 to tip over can be suppressed.

[0067] (7) The wind power generation equipment 1, 1B according to the seventh embodiment is the wind power generation equipment 1, 1B of (5) or (6), wherein the strut 29 is provided with other ballast.

[0068] This allows us to set the weight distribution of floating body 2, including other ballast. [Explanation of symbols]

[0069] 1. Wind power generation facilities 2, 2B Floating Body 3. Wind power generation equipment 21, 21E First Column 21a Cylindrical part 21c center 21d Lower plate part 21s First hollow part 21t upper plate section 22, 22A, 22B Second Column 22Ac, 22Bc center 22a Cylindrical part 22d Lower plate part 22s Second hollow part 22t upper plate section 25, 25A, 25B, 25C Connecting members 25c, 26c hollow part 26, 26A, 26B protrusion 27 First ballast 28 Second ballast 29 strut 32 Windmill 33 Towers 34 Nasser 35 rotors 35a Hub 35b blade

Claims

1. Floating body and, A wind power generation device comprising a wind turbine mounted on the floating body, The floating body is Supporting the wind turbine, a first column having a first hollow section, When viewed from above, a plurality of second columns are provided symmetrically with respect to an imaginary line that passes through the first column and extends horizontally, each having a second hollow section. A plurality of first connecting members are located below the water surface and connect the first column and the second column, When viewed from above, the first connecting member has a projection that extends in the direction from the second column away from the first column, A wind power generation facility equipped with [specific features / equipment].

2. The first ballast provided in the first hollow section, A second ballast is provided in each of the second hollow sections, The wind power generation equipment according to claim 1, comprising:

3. The first connecting member and the protruding portion each have a hollow portion. The wind power generation equipment according to claim 1.

4. The wind power generation equipment according to claim 3, wherein at least one of the first connecting member and the protruding portion is provided with other ballast.

5. Located below the water surface, it connects the first connecting members and further comprises struts with greater buoyancy than the first connecting members. The wind power generation equipment according to claim 1.

6. Floating body and, A wind power generation device comprising a wind turbine mounted on the floating body, The floating body is Supporting the wind turbine, a first column having a first hollow section, When viewed from above, a plurality of second columns are provided symmetrically with respect to an imaginary line that passes through the first column and extends horizontally, each having a second hollow section. A plurality of first connecting members are located below the water surface and connect the first column and the second column, A strut located below the water surface connects the first connecting members and has greater buoyancy than the first connecting members, A wind power generation facility equipped with [specific features / equipment].

7. The wind power generation equipment according to claim 5 or 6, wherein the strut is further provided with other ballast.

Images