Work and maintenance device and method

Abstract

An operation and maintenance apparatus for a floating wind turbine (1) includes: a floating base structure (2) on which at least one wind turbine unit (3) is located, a maintenance vessel (11), and a portable crane (14); the floating base structure (2) has an interface capable of receiving and securely locking the crane (14) to the base structure (2), and the maintenance vessel (11) has a marine crane (12) capable of lifting the portable crane (14) from the vessel (11) onto the base structure (2). A method for replacing components using the apparatus is also described.

Description

Technical Field

[0001] The present invention relates to an operation and maintenance apparatus for a floating wind turbine, and a method for performing the replacement of major components of a floating wind turbine, such as replacing wind turbine blades and gear units. Background Technology

[0002] Operating a crane at sea is challenging, especially when the unit where the work is being performed is a floating unit. There are, in principle, two approaches to this. The first is to deploy a vessel equipped with a suitable crane alongside the floating unit and use that crane to move objects between that vessel (or another vessel) and the floating unit. The second approach is to deploy a crane on the floating unit and use that crane to move objects between the support vessel and the floating unit, as well as to perform tasks such as installing equipment on the floating unit.

[0003] In the first option, due to wave motion, all operations must be performed while the ship and units are in motion. This requires complex heave compensation and can only be carried out during periods of relatively calm conditions.

[0004] The second option only requires turbulence compensation during loading or unloading, but it requires installing a crane on the floating unit equipped with the wind turbine.

[0005] There are several examples of floating wind turbines with cranes mounted on them:

[0006] DE19741988 illustrates a wind turbine in which a crane is temporarily attached to the tower of the wind turbine. The crane is capable of moving up and down along the tower.

[0007] DE19647515 illustrates a similar crane that is capable of installing additional tower segments on top of the tower segments to which it is connected.

[0008] US20180282134 also shows a crane that is attached to the tower of a wind turbine and is capable of moving up and down along the tower. This crane is suitable for replacing the blades of a wind turbine.

[0009] DE102012002720A1 shows another crane connected to the tower structure.

[0010] US9120652 illustrates a wind turbine in which a small maintenance crane is arranged inside the nacelle. When the maintenance crane is needed, a hatch can be opened through which the crane can be accessed.

[0011] GB2558242A shows a larger maintenance crane mounted on the top of the nacelle.

[0012] WO2020167137 shows an example of a crane arranged on a support vessel, but the support vessel is connected to the base of a wind turbine.

[0013] WO2020043254 illustrates a support vessel in which at least a portion of a single crane is lifted onto a support structure above the vessel. The system compensates for the relative motion between the vessel and the support structure.

[0014] WO2020043256 relates to a method for mounting a crane from a ship to a portion of an offshore wind turbine generator, wherein a detachable crane coupling has a first coupling to that portion of the offshore wind turbine generator.

[0015] In all known solutions, except for WO2020167137, the crane is mounted on the wind turbine tower. This means the tower must be designed to support both the crane and its load. It must also have an outer surface for attaching the crane. Furthermore, the crane's operating range is limited by this placement, and care must be taken to prevent the crane from damaging the rotor and blades.

[0016] If the crane is not permanently attached to the tower, installing and removing it every time it is needed can be cumbersome. If it is permanently attached, maintenance becomes a challenge.

[0017] Therefore, a more versatile crane is needed that can be used on a variety of floating wind turbines without requiring the tower to be designed to support it. It is also desirable that this crane be easy to install and not require particularly heavy-duty equipment.

[0018] Furthermore, WO2012038487 describes a method for installing an offshore tower, wherein a gravity structure is located on the seabed and a crane is placed on the structure. This published text does not describe a semi-submersible base structure floating in the water. Moreover, since the crane is placed on the gravity structure, this solution does not require consideration of any relative movement between the crane and the base structure due to wave motion. Summary of the Invention

[0019] These objectives can be achieved by an operation and maintenance apparatus for a floating wind turbine, comprising: a floating base structure on which at least one wind turbine unit is mounted, a service operation vessel, and a portable crane. The floating base structure has an interface for receiving and fixing the crane to the base structure, and the service operation vessel has a marine crane capable of lifting the portable crane from the vessel onto the base structure.

[0020] In a preferred embodiment, the device includes a support structure for receiving components to be mounted on the wind turbine, such as wind turbine blades or gear units. This support structure has an interface that mates with and securely locks into place on the floating base structure. This ensures that a portable crane can lift these components without considering relative movement caused by wave action.

[0021] If the component is a wind turbine blade, it is preferably arranged in a support, and if there are multiple blades, they are stacked in multiple supports.

[0022] When the component consists of multiple blades, they are preferably stacked vertically in a support structure. This takes up less space on the deck of the supporting vessel, and the stack can be lifted as a whole.

[0023] Conveniently, the support structure is a truss beam, which is lightweight but high in strength.

[0024] If the floating base structure has at least two pontoons, one pontoon can accommodate a portable crane, while the other pontoon can accommodate a support structure with these components.

[0025] By remotely operating a portable crane from the support vessel, the risks of having personnel board the floating wind turbine were eliminated.

[0026] A method for replacing components (such as wind turbine blades or gear units) of a floating wind turbine includes the following steps: deploying a maintenance vessel near the floating wind turbine; using a marine crane on the vessel to lift a portable crane from the vessel onto the base structure of the floating wind turbine; securely locking the portable crane to the base structure; lifting a component support structure onto the base structure; securely locking the component support structure to the base structure; using the portable crane, lifting the component to be replaced from the wind turbine onto the component support structure; lifting the component from the component support structure onto the vessel; lifting a new component onto the component support structure; lifting the new component onto the wind turbine and installing it in the position where the component to be replaced was previously; lifting an empty support structure onto the vessel; and using the marine crane to lift the portable crane onto the vessel.

[0027] In a preferred embodiment applicable to replacing wind turbine blades, the method includes the following steps: using a portable crane to lift worn blades one by one from the rotor of the wind turbine onto the support structure, lifting a stack of worn blades from the blade support structure onto the vessel, lifting a stack of new blades onto the blade support structure, and then using a portable crane to lift the new blades one by one onto the rotor. Attached Figure Description

[0028] The invention will now be described in further detail with reference to exemplary embodiments shown in the accompanying drawings, wherein:

[0029] Figure 1 The apparatus of the present invention is shown, with the maintenance vessel deployed alongside the floating wind turbine.

[0030] Figure 2 The image shows a portable crane being lifted off the ship's deck.

[0031] Figure 3 The image shows a portable crane mounted on a floating base structure of a wind turbine.

[0032] Figure 4 The diagram shows the support structure for the wind turbine blades mounted on the base structure.

[0033] Figure 5 The image shows the first worn blade being hoisted from the rotor to the support structure.

[0034] Figure 6 The second worn blade has been lifted from the rotor to the support structure.

[0035] Figure 7 The third wear blade has been lifted from the rotor to the support structure.

[0036] Figure 8The image shows the stacked wear blades being lifted from the support structure onto the ship.

[0037] Figure 9 The stacked wear blades were shown to have been placed on the ship.

[0038] Figure 10 A stack of new blades has been hoisted onto the support structure.

[0039] Figure 11 The new blades have been installed on the rotor, and

[0040] Figure 12 The supporting structure and portable crane have been hoisted onto the ship. Detailed Implementation

[0041] Although the following description of the embodiments details the replacement of turbine blades, it should be understood that the apparatus and method can be used for other types of maintenance, such as replacing gear units or other components whose weight does not exceed the lifting capacity of a portable crane. For example, the portable crane may have a lifting capacity of 100 metric tons.

[0042] Figure 1 The image shows a floating wind turbine unit 1. It includes a floating base structure 2 and a wind turbine 3. The floating base is triangular in shape and includes three cylindrical floats 4, 5, and 6, which are connected by a tubular crossbeam 7. The wind turbine 2 has a tower 8 connected to one of the floats 5, and a rotor 9 with blades 10.

[0043] The wind turbine unit shown is merely an example. It can have other designs, such as the one shown in co-pending document NO20201030. The only requirement is that it can support a crane, as described below.

[0044] Next to the floating wind turbine unit 1 (hereinafter referred to as the "unit") is a support vessel 11. The vessel 11 is equipped with a marine crane 12, which is permanently attached to the vessel 11. It also has a cargo area 13 located on the deck. It can be seen that the cargo initially consists of a portable crane 14, a truss beam 15, a first set of empty blade supports 18, and a second set of blade supports 16 with blades 17 assembled, all of which will be explained further below.

[0045] Ship 11 can be moored next to the unit or kept in place by dynamic positioning (DP).

[0046] Figure 2-12The process of replacing blade 10 of wind turbine 1 with new blade 17 is illustrated step-by-step. This is an operation that must be performed periodically due to wear and tear on the blades caused by wind, rain, ice, heating and cooling, insects, birds, and lightning strikes. Depending on local conditions, the blades may need to be replaced every 10-20 years.

[0047] Figure 2 This demonstrates the first step of the blade replacement operation. Marine crane 12 has begun lifting portable crane 14 from cargo deck 13.

[0048] exist Figure 3 In this design, a portable crane 14 is positioned atop one of the pontoons 4. The pontoon 4 is equipped with an interface that allows for easy docking with the bottom of the crane 14. The crane 14 is securely locked to the pontoon 4 via this interface. The design of the interface and locking mechanism will be the choice of someone skilled in the art. Many options are available in this field.

[0049] The portable crane can have its own power source, such as a battery or generator on board, or a cable can be extended from the ship 11 to the crane 14. The crane 14 can be easily operated remotely from the ship 11. Thus, the operator can remain at a safe distance and track the crane's operation via a camera mounted on the crane 14.

[0050] When crane 14 is in place on unit 1, it can be used to lift items from ship 11 to that unit. However, if more convenient, crane 12 on the ship can also be used.

[0051] Figure 4 The diagram shows the truss beam 15 being lifted from the ship and installed on top of the pontoon 6. The interface between the beam 15 and the pontoon 6 can be the same as the interface between the crane 14 and the pontoon 5. On top of the beam 15 is a first support consisting of two support members 18a and 18b.

[0052] We can now begin removing the working blade 10. Figure 5 In the process, the first blade 10a has been lifted from the rotor 9 by the crane 14 and placed inside the supports 18a and 18b. Next, a new bracket including supports 18c and 18d is placed on top of the first bracket, and the crane 14 lifts the second worn blade 10b from the rotor 9 and places it inside the brackets 18c and 18b, as follows. Figure 6 As shown.

[0053] Using the same method as with blade 10b, the final blade 10c is lifted and placed in the support, thus, as Figure 7 As shown, all the blades are stacked in an orderly fashion on top of beam 15.

[0054] like Figure 8 As shown, the stack of blades 10a, 10b, and 10c are lifted off beam 15. This can be done by a marine crane 12 or a portable crane 14. However, it is generally more convenient to use a crane on the unit where the load is to be placed. This is because, in the presence of wave motion, the lifting phase is easier than the releasing phase.

[0055] exist Figure 9 In the middle, the stack of working blades 10a, 10b and 10c have been placed on the cargo deck 13 of ship 11.

[0056] Now, the stack of new blades 17 is lifted from ship 11 and placed on truss beam 15. A portable crane can then lift the blades 17 into the engine room for installation. As each blade 17 is lifted, the support supporting it is lifted onto ship 11.

[0057] exist Figure 11 In the middle, all the new blades 17 have been installed. Now, the truss beam 15 is lifted onto the ship. Once this is complete, the crane 14 itself is released and lifted onto the ship by the marine crane 12. Figure 12 As shown, the operation is now complete. Ship 11 can now return to port to unload the worn blades 10, and if necessary, can also take a new stack of blades on board to replace the blades of another wind turbine.

[0058] Of course, truss beam 15 can be replaced by another reliable support structure for the blades, such as a platform. The blades can also be arranged side by side on the support structure. However, stacking is more convenient because it saves space on the deck.

[0059] The preferred method for securing a portable crane is to do so without requiring any personnel to be present on the floating base structure, such as by means of an automated clamp.

Claims

1. An operation and maintenance apparatus for a floating wind turbine unit (1), comprising: The device comprises at least one wind turbine (3) on which a floating base structure (2), a maintenance vessel (11), and a portable crane (14) are located; the floating base structure (2) has an interface capable of receiving the crane (14) and securely locking the crane (14) to the floating base structure (2); the maintenance vessel (11) has a marine crane (12) capable of lifting the portable crane (14) from the vessel (11) onto the floating base structure (2); characterized in that the device further comprises a support structure for receiving components to be installed on the wind turbine (3), the support structure having an interface that engages with and securely locks onto the interface on the floating base structure (2).

2. The apparatus according to claim 1, characterized in that, The support structure includes at least one set of brackets (16, 18) for receiving at least one wind turbine blade (10, 17).

3. The apparatus according to claim 2, characterized in that, At least three wind turbine blades (10, 17) are stacked in brackets (16, 18) on the support structure.

4. The apparatus according to any one of claims 1-3, characterized in that, The supporting structure includes a truss beam (15).

5. The apparatus according to claim 1, characterized in that, The floating base structure (2) includes at least two pontoons (4,6), each pontoon having an interface for receiving the portable crane (14) and one of the support structures, respectively.

6. A method for replacing components of a floating wind turbine unit (1), comprising the following steps: a. Deploy maintenance vessel (11) near the floating wind turbine unit (1). b. Using the marine crane (12) on the ship (11), lift the portable crane (14) from the ship (11) onto the floating base structure (2) of the floating wind turbine unit (1). c. Securely lock the portable crane (14) to the floating base structure (2). d. Lift the component support structure (18a, 18b) onto the floating base structure (2), e. Securely lock the component support structure (18a, 18b) to the floating base structure (2). f. Using the portable crane (14), the component to be replaced is lifted from the wind turbine (3) onto the component support structure (18a, 18b). g. Lift the component from the component support structure (18a, 18b) onto the ship (11), h. Hoist the new component onto the component support structure (18a, 18b). i. Lift the new component onto the wind turbine (3) and install it in the position where the component to be replaced was previously located. j. Lift the empty component support structures (18a, 18b) onto the ship (11), and k. Use the marine crane (12) to lift the portable crane (14) onto the ship.

7. The method according to claim 6, characterized in that, The component is a set of wind turbine blades (10, 17), wherein... l. The lifting as defined in step f includes: using a portable crane (14) to lift the worn wind turbine blades (10, 17) one by one from the rotor (9) of the wind turbine (3) onto the component support structure (18a, 18b). m. The lifting as defined in step g includes: lifting a stack of worn blades (10) from the component support structure (18a, 18b) onto the ship (11), n. The lifting as defined in step h includes: lifting a stack of new blades (17) onto the component support structure (18a, 18b), and o. The lifting defined in step i includes: using the portable crane (14) to lift the new blades (17) one by one onto the rotor (9).

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