JP2022183904A - Offshore wind power generating set assembling method and floating structure - Google Patents

Abstract

To provide an offshore wind power generating set assembling method which secures the stability of a floating structure at construction, and is resultantly enabled in an improvement of construction performance, and the floating structure.SOLUTION: An offshore wind power generating set assembling method comprises an anchoring process for anchoring a floating structure 2 in a prescribed position, a temporary fastening process for temporarily fastening a tower 3 which is suspended by a crane 12 in a state that the tower is erected on the floating structure 2, and a tower self-erecting process for making the tower 3 self-erect on the floating structure 2. A ballast material 7 for securing horizontality after the installation of the tower, and a ballast water storage tank for storing ballast water 8 for securing the horizontality before the installation of the tower are arranged at the floating structure 2.SELECTED DRAWING: Figure 4

Description

TECHNICAL FIELD The present invention relates to a method for assembling a water wind power generation facility and a floating structure.

Wind power generation is one of the renewable energies aimed at reducing greenhouse gas emissions. Since the noise and vibration of the wind turbine may affect the living environment, it is desirable to install the wind power generation facility away from the residential area. Therefore, there are cases where wind power generation facilities are installed on the sea (on the water).
On the other hand, when constructing a wind power generation facility in a deep water position, it takes time and effort to construct a foundation structure to reach the bottom and construct piles and the like on the bottom of the water. Therefore, in some cases, a wind power generation facility is constructed by erecting a tower on a floating structure moored on water.
For example, Patent Document 1 discloses a floating wind power generation facility comprising a floating body, a mooring cable connected to the floating body, a tower erected on the floating body, and a nacelle and wind turbine blades installed on the top of the tower. there is The construction process of the waterborne wind power generation facility of Patent Document 1 is as follows. First, after the floating body is towed sideways to a predetermined position, ballast water is injected into the floating body to make the floating body stand up. At this time, a wire extending from a balance adjusting floating body provided near the floating body is attached to the lower part of the floating body, and the wire is sent out as the floating body stands up. When the floating body stands up, ballast material is thrown into the bottom of the floating body and the floating body is moored with mooring cables. Then, using a crane, the tower is fixed to the floating body in an upright state, and then the nacelle and blades are installed on the head of the tower. At this time, the rotation of the floating body is controlled by feeding and unwinding the wire extending from the balance adjusting floating body.
However, a skilled technique is required to control the rotation of the floating body with a wire. Further, the control of the rotation by the balance adjusting floating body is performed after the floating body is rotated, and does not suppress the occurrence of the rotation itself. Therefore, it is difficult to ensure stability when fixing the tower. Furthermore, it takes time and effort to erect the sideways floating body.

JP 2012-201219 A

An object of the present invention is to provide a method for assembling a floating wind power generation facility and a floating structure that can secure the stability of the floating structure during construction and, as a result, improve the workability.

A method for assembling a floating wind power generation facility according to the present invention for solving the above problems includes a mooring step of mooring a floating structure at a predetermined position, and a state in which a tower suspended by a crane is erected on the floating structure. and a tower self-supporting step of making the tower self-supporting on the floating structure. The floating structure is provided with ballast material for ensuring horizontality after installation of the tower, and ballast water storage tanks for storing ballast water for ensuring horizontality before installation of the tower, In the tower self-supporting step, the ballast water stored in advance in the ballast water storage tank is discharged, and the tower is removed from the crane.
According to this method for assembling a floating wind power generation facility, the horizontality of the floating structure is ensured by the ballast material and the ballast water storage tank before the tower self-supporting process, so the rotation of the floating structure is suppressed. Therefore, stability is ensured when erecting the tower. In addition, when the tower is self-supporting on the floating structure, the ballast water is discharged from the ballast water storage tank, and the balance is secured by the tower and the ballast material, ensuring stability during construction.

Here, the amount of ballast water stored in advance in the ballast water storage tank is an amount that acts on the floating structure with an overturning moment greater than the overturning moment acting on the floating structure on which the tower is installed. is preferred. In this way, the horizontality of the floating structure is ensured even when the overturning moment increases due to the mounting of the wind turbine body (nacelle, blades, etc.) to the tower.
In addition, in the wind turbine installation process of installing the wind turbine body (nacelle, blades, etc.) to the tower, in parallel with the installation work of the wind turbine body, the ballast water is discharged from the ballast water storage tank or the amount of ballast material is increased. By doing so, horizontality is ensured.

The floating structure of the present invention constitutes the foundation of a water-based wind power generation facility, and includes a ballast material provided at a position away from the installation position of the tower and a ballast material provided near the installation position of the tower. The ballast water storage tank is provided with a drain port for discharging the ballast water stored in the ballast water storage tank to the outside.
According to such a floating structure, horizontality can be ensured by adjusting the amount of ballast water in the ballast water storage tank. Therefore, by adjusting the amount of ballast water before and after erecting the tower, stable construction is possible.

According to the method for assembling a floating wind power generation facility and the floating structure of the present invention, it is possible to secure the stability of the floating structure during construction, and as a result, it is possible to improve the workability.

1 is a side view showing a water wind power generation facility according to an embodiment of the present invention; FIG. (a) A schematic diagram showing the floating structure of the present embodiment, (b) is a schematic diagram showing a state where a tower is installed on a conventional floating structure. 1 is a flow chart of a method for assembling a water wind power generation facility according to an embodiment of the present invention; FIG. 10 is a side view showing each step of the method for assembling a floating wind power generation facility, wherein (a) is a mooring step, (b) is a temporary fixing step, (c) is a tower self-supporting step, and (d) is a tower following (c). It is an independent process. It is the schematic which shows the floating structure which concerns on another form, Comprising: (a) is a side view, (b) is a top view.

In this embodiment, a floating wind power generation facility 1, which is a power generation facility provided on water, will be described. FIG. 1 shows a water wind power generation facility 1 of this embodiment. A water-based wind power generation facility 1 of the present embodiment performs wind power generation while moored on the water. As shown in FIG. 3 and a wind turbine main body 4 provided at the head of the tower 3.
The floating structure 2 constitutes the foundation of the water wind power generation facility 1 . The outline of the floating structure 2 is shown in FIG. The floating structure 2, as shown in FIG. there is

The tower 3 is a pillar for supporting the wind turbine main body 4 . It is assumed that the tower 3 is provided at a position eccentric from the center of the floating structure 2 (the amount of eccentricity e1 of the tower 3). The tower 3 of this embodiment is provided on one end side (left side in FIG. 2) of the center of the floating structure 2 .
The wind turbine main body 4 includes blades 10, a nacelle 11, and the like (see FIG. 1). The wind turbine main body 4 is installed on the head of the tower 3 after the tower 3 is erected on the floating structure 2 .

The first tank 5 is provided within the floating structure 2 and accommodates ballast material 7 . In this embodiment, the first tank 5 is provided at the other end of the floating structure 2 (right end in FIG. 1). The first tank 5 of this embodiment is provided at a position with an eccentricity e<b>2 from the center of the floating structure 2 . The first tank 5 is a hollow box-shaped member formed continuously in the width direction inside the floating structure 2 . A ballast material inlet communicating with the inside of the first tank 5 is formed on the upper surface of the floating structure 2 so as to correspond to the position of the first tank 5 .
When the tower 3 is installed on the floating structure 2, the first overturning moment M1 (=W1×e1) acts on the floating structure 2 due to the weight W1 of the tower 3. , the floating structure 2 inclines (rotates) as shown in FIG. 2(b). Therefore, the capacity of the first tank 5 generates a second overturning moment M2 (=W2×e2) that cancels the first overturning moment M1 acting on the floating structure 2 by installing the tower 3 and ensures horizontality. The size is set so as to accommodate the ballast material 7 having a weight W2 that allows the ballast material to be stored.

The second tank 6 is a ballast water storage tank that stores ballast water 8, and is provided on the upper surface of the floating structure 2 as shown in FIG. 2(a). In this embodiment, a second tank 6 is provided at one end of the floating structure 2 (left end in FIG. 2(a)). The second tank 6 is a hollow box-shaped member and is provided on one end side of the installation location of the tower 3 . A drain port 9 for draining the ballast water 8 is formed in a side surface of the outside (one end side) of the second tank 6 . The drain port 9 faces the outside of the floating structure 2, and when the drain port 9 is opened, the ballast water is naturally drained, and the drained ballast water 8 directly reaches the water surface around the floating structure 2. flow down
The second tank 6 is provided at a position eccentric from the center of the floating structure 2 (amount of eccentricity e3). A moment M3 (=W3×e3) acts. The weight of the ballast water 8 stored in the second tank 6 is such that, in the state before the tower 3 is installed, the third overturning moment M3 that cancels the second overturning moment M2 acting on the floating structure 2 due to the ballast material 7 is equal to the weight of the floating structure. Let it be the size that acts on the object 2.

A method for assembling a water-based wind power generation facility according to this embodiment will be described below. Figure 3 shows the method of assembling the floating power generation facility. As shown in FIG. 3, the method for assembling a floating wind power generation facility of this embodiment includes a mooring step S1, a temporary fixing step S2, a tower self-supporting step S3, and a wind turbine mounting step S4. FIGS. 4(a) to 4(d) show the working conditions of each step.
In the mooring step S1, as shown in FIG. 4(a), the floating structure 2 is moored at a predetermined position. The floating structure 2 is towed to a predetermined position and moored to a stake or the like (not shown). Ballast material 7 is put into the first tank 5 of the floating structure 2 to ensure the horizontality of the floating structure 2 after the tower 3 and the tower body 4 are installed. That is, the first tank 5 contains ballast material 7 having a weight that causes the floating structure 2 to generate a second overturning moment M2 greater than or equal to the first overturning moment M1 generated when the tower 3 is installed on the floating structure 2. is stored. Further, the second tank 6 stores ballast water 8 for ensuring horizontality of the floating structure 2 before the tower 3 is installed. That is, the second tank 6 has a third overturning moment M3 which is equal to or greater than the first overturning moment M1 acting on the floating structure 2 on which the tower 3 is installed and which is equivalent to the second overturning moment M2 generated by the ballast material 7. The amount of ballast water 8 that acts on the floating structure 2 is stored.

In the temporary fixing step S<b>2 , the tower 3 is temporarily fixed on the floating structure 2 . As shown in FIG. 4( b ), the tower 3 is erected on the floating structure 2 using a crane 12 , and bolts or the like are attached to the floating structure 2 while maintaining the suspension by the crane 12 . Temporarily fasten by That is, in the temporary fixing step S2, since the tower 3 is suspended by the crane 12, the weight of the tower 3 does not act on the floating structure 2, and the ballast material 7 and the ballast water 8 balance the floating structure 2. is maintained. In this embodiment, a crane 12 provided on a crane ship 13 is used.

In the tower self-supporting step S3, the tower 3 is released from the crane 12 to allow the floating structure 2 to self-support the tower. The tower 3 is erected on the floating structure 2 while being suspended by the crane 12, as shown in FIG. 4(c). Also, the ballast water 8 stored in the second tank 6 is discharged. When the ballast water 8 is discharged from the second tank 6, the weight of the ballast material 7 (first tank 5) acting on the other end side of the floating structure 2 causes the floating structure 2 to generate a rotational force (second overturning moment M2). However, since the tower 3 is in contact with the upper surface of the floating structure 2 on one end side, the horizontality of the floating structure 2 is maintained. As the second tank 6 drains, the load of the tower 3 acting on the crane 12 is reduced. That is, when the ballast water 8 is discharged from the second tank 6, the one end side of the floating structure 2 tries to float up and naturally pushes back the tower 3, so that the horizontality is automatically maintained. By discharging the ballast water 8 from the second tank 6, at the stage where the balance of the floating structure 2 is secured by the weight W1 of the tower 3 and the weight W2 of the ballast material 7, FIG. Remove the tower 3 from the crane 12 (remove the rigging wire from the tower 3), as shown in FIG.

In the wind turbine mounting step S4, the wind turbine main body 4 is attached to the tower 3 (see FIG. 1). A crane 12 is used to attach the wind turbine main body 4 to the tower 3 . In the wind turbine mounting step S<b>4 , the ballast water 8 is discharged from the second tank 6 in parallel with the work for mounting the wind turbine main body 4 . The ballast water 8 is discharged according to the timing of installation of the wind turbine main body 4 (the blades 10 and the nacelle 11) on the tower 3. When the ballast water 8 is discharged from the second tank 6, a rotational force acts on the floating structure 2 due to the weight W2 of the ballast material 7. 2 horizontality is ensured.

According to the method for assembling the floating wind power generation facility of this embodiment, the horizontality of the floating structure 2 is ensured by the first tank 5 (ballast material 7) and the second tank 6 (ballast water 8) until the tower self-sustaining process. Therefore, the rotation of the floating structure 2 is suppressed. That is, since stability and horizontality are ensured when erecting the tower 3, workability is improved. Also, when the tower 3 is allowed to stand on its own on the floating structure 2, the ballast water 8 is drained from the second tank (ballast water storage tank) 6, so that the balance between the tower 3 and the ballast material 7 is ensured. . In other words, stability and horizontality are ensured when the crane supports the tower 3 . Since the ballast water 8 can be drained from the second tank 6 instantly by simply opening the drain port 9, it can be performed easily and in a short time compared to the case of using a pump. As described above, according to the method for assembling the floating wind power generation facility and the floating structure 2 of the present embodiment, when the wind turbine is assembled on the floating structure 2, the center of gravity of the floating structure 2 and the center of gravity of the tower 3 do not match. Even in such a case, since the floating structure 2 is prevented from tilting when the tower 3 is placed on top of it, it is possible to perform efficient construction while ensuring horizontality.

The amount of ballast water 8 stored in advance in the second tank 6 is equal to or greater than the overturning moment (first overturning moment M1) acting on the floating structure 2 when the tower 3 is installed (third overturning moment M1). Since the moment M3) is the amount that acts on the floating structure 2, even if the overturning moment acting on the floating structure 2 increases due to the attachment of the wind turbine main body 4 to the tower 3, etc. Horizontality is ensured. That is, when the wind turbine body 4 (the blades 10 and the nacelle 11) is attached to the tower 3, the ballast water 8 is drained from the second tank 6 so as to cancel the overturning moment due to the installation of the wind turbine body 4, so that the floating body Horizontality of the structure 2 can be ensured. In this way, the floating structure 2 can adjust the amount of the ballast water 8 in the second tank 6 according to the construction status of the tower 3 and the wind turbine main body 4, thereby ensuring horizontality and stable operation. Allows construction.

Since the horizontality of the floating structure 2 is ensured using the ballast water 8 (the second tank 6), the time required for horizontal adjustment during construction can be shortened. In addition, since the ballast water 8 can be discharged in a short time, the time required for the crane 12 to be restrained can be shortened, and the cost required for using the crane 12 can be reduced. By diverting it to assembly, it is possible to shorten the overall construction period.

Although the embodiments according to the present invention have been described above, the present invention is not limited to the above-described embodiments, and the constituent elements described above can be appropriately modified within the scope of the present invention.
For example, the installation location of the first tank 5 is not limited to within the floating structure 2, and may be installed on the floating structure 2, for example. Also, in the above embodiment, the ballast material 7 is put into the first tank 5 , but the ballast material 7 may be directly placed inside or on the floating structure 2 .
Although water is used as the ballast material 7 in the above embodiment, the material constituting the ballast material 7 is not limited, and may be, for example, concrete or crushed stone. Moreover, the ballast material 7 used at the time of construction may be appropriately replaced with other materials, equipment, and the like. For example, when power transmission equipment is installed on the other end side of the floating structure 2 (the side opposite to the tower 3), the ballast material 7 in the first tank 5 may be discharged along with the installation of the power transmission equipment.
Although the ballast water 8 is discharged from the second tank 6 in the above embodiment, the horizontality may be maintained by moving the ballast water 8 to the first tank 5 .
Further, when the ballast material 7 is installed at the same time as the tower 3 is installed, the second tank 6 can be omitted.

The installation location of the second tank (ballast water storage tank) 6 is not limited to above the floating structure 2, and may be inside the floating structure 2, for example. Further, in the above embodiment, one second tank 6 is provided outside (one end side) of the floating structure 2 from the installation location of the tower 3 (see FIG. 1), but the number of second tanks 6 and The installation location is not limited. For example, as shown in FIGS. You can set them one by one.
In the above embodiment, in the wind turbine mounting step S4, the ballast water 8 is discharged from the second tank 6 in parallel with the mounting work of the wind turbine main body 4. The stability (horizontality) of the floating structure 2 may be ensured by increasing the amount of 7.
The crane 12 to be used is not limited to one installed on the crane ship 13. For example, when installing the tower 3 on the floating structure 2 moored in the dock or on the quay, the crane 12 may be installed adjacent to the dock or the quay. It suffices to use the crane 12 provided as a

1 water wind power generation facility 2 floating structure 3 tower 4 wind turbine body 5 first tank 6 second tank (ballast water storage tank)
7 ballast material 8 ballast water 9 drain 10 blade 11 nacelle 12 crane

Claims (4)

a mooring step of mooring the floating structure at a predetermined position;
a temporary fixing step of temporarily fixing the tower suspended by a crane while standing on the floating structure;
a tower self-supporting step of making the tower self-supporting on the floating structure;
A method for assembling a floating wind power generation facility comprising:
The floating structure is provided with a ballast material for ensuring horizontality after installation of the tower, and a ballast water storage tank for storing ballast water for ensuring horizontality before installation of the tower,
The method for assembling a floating wind power generation facility, wherein in the tower self-sustaining step, the ballast water stored in advance in the ballast water storage tank is discharged, and the tower is removed from the crane. The amount of ballast water stored in advance in the ballast water storage tank is an amount that acts on the floating structure with an overturning moment greater than the overturning moment acting on the floating structure on which the tower is installed. The method for assembling a water wind power generation facility according to claim 1. further comprising a wind turbine mounting step for mounting the wind turbine main body on the tower;
In the wind turbine mounting step, the ballast water is discharged from the ballast water storage tank or the amount of the ballast material is increased in parallel with the mounting work of the wind turbine main body. 3. The method for assembling a water wind power generation facility according to 2. A floating structure that constitutes the foundation of a water-based wind power generation facility,
Ballast material provided at a position away from the installation position of the tower,
a ballast water storage tank provided near the installation position of the tower,
A floating structure, wherein a side surface of the ballast water storage tank is formed with a drain port for discharging ballast water in the ballast water storage tank to the outside.

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