Patent Application
20230160366
The present disclosure relates to a device for making a wind turbine tower.
The disclosure further relates to a nacelle for a wind turbine and including the device, and to a method of making a wind turbine tower.
Wind turbines increase in size in terms of nominal power output as well as in terms of physical dimensions of the individual parts of the wind turbine. As a consequence, the size of the tower increases and transport and assembly operations become more complicated.
It is an object of embodiments of the disclosure to facilitate transport and assembly and in wind turbine manufacturing, to allow improved assembly conditions and potentially to increase safety and working conditions.
For these and other purposes, embodiments of the disclosure, in a first aspect, provides a wind turbine tower assembly device comprising a tower interface configured to be attached to a wind turbine tower during construction of the wind turbine tower. The device comprises a nacelle interface which can be attached to a part of a nacelle of a wind turbine, e.g. to the main frame of the nacelle and particularly to a yaw arrangement of the main frame. The interface may thereby be arranged to place the nacelle above a free end of the wind turbine tower to which the device is attached.
The device comprises a lifting structure configured to move the nacelle interface relative to the tower interface to create a space between the free end of the wind turbine tower and the nacelle interface. A unit receiving structure is configured to insert a tower unit into the space, and a tower assembly structure is configured for joining the tower unit to the free end of the tower.
The device facilitates efficient assembly of towers for wind turbines.
The tower interface, the nacelle interface, and the lifting structure may form part of a strand jack or similar crawling structure, and particularly they may form part of a structure having a clamp structure arranged to clamp about a surface, particularly an outer surface, of the tower at axially offset upper and lower tower locations. The clamp structure may be power operated, e.g. by electric or hydraulic power, may include power actuated, e.g. hydraulic or electric, actuators, and they may include different structures for fixing to the tower, e.g. friction pads being pressed against the surface. The crawling structure may also include a caterpillar walking structure configured to change a distance between the upper and lower locations where the clamps engage the tower. The crawling structure may further include a controller configured to provide a repeated procedure of releasing the clamp at one of the upper and lower locations while maintaining the clamping at the other one of the upper and lower locations, changing the distance between the upper and lower locations, clamping the tower by use of the released clamp, and repeating the procedure to provide a caterpillar like walking along the wind turbine tower.
The tower assembly structure is configured for joining the tower unit to the free end of the tower. In one embodiment, the tower units are fitted with bolt flanges, and the assembly structure includes necessary tools for bolting such flanges. In another embodiment, the tower units are to be joined by welding or riveting, and the assembly structure comprises welding equipment or riveting equipment. Particularly, the assembly structure may comprise a welding robot for full automatic seam welding, and the welding robot may particularly comprise 2, 3, or 4 independent welding guns arranged at a certain distance to enable simultaneous welding at different locations along the periphery of the intersection between the free end of the tower and the tower unit. The assembly structure may further comprise seam preparation equipment e.g. configured to cut or mill a specific groove shape for welding, e.g. a V-groove shape.
An encapsulation extending in the space and forming an enclosed area in the space may ensure better working conditions and a controllable climate. The encapsulation may e.g. be a steel encapsulation, tarp encapsulation, an encapsulation made of panels of steel or polymer material etc. The encapsulation may e.g. be tubular to provide an essentially uniform distance from an outer surface of the tower to an inner surface of the encapsulation. In the encapsulation, different working areas may be defined. In one example, the encapsulation forms a working area for workers, e.g. for inspecting the welding or for manually welding or manual riveting of tower units onto the free end of the tower.
A partition structure may facilitate separation of the enclosed area into an upper enclosed area and a lower enclosed area. a welding area, e.g. for manual welding or for robotised welding may be formed in one of the enclosed areas, particularly in the upper enclosed area. A surface treatment unit for treatment of the wind turbine tower e.g. by abrasive cleaning and painting etc. may be provided in the other enclosed area, particularly in the lower enclosed area. Automatic or manually operated equipment may be provided for final quality inspection of the welding and/or the surface treatment.
In a further embodiment the encapsulation may comprise additional partitioning structures to facilitate further separation of the enclosed area into additional enclosed areas to separate the various treatment types and facilities of the tower assembly structure.
A compartment may be provided as a part of the assembly device. The compartment may form accommodation for objects such as workers, tools, or spare parts.
The tower assembly device can be supported solely by the tower or in combination with external support legs that are build up during construction of the tower. For that purpose, the tower assembly device may comprise a support structure which can be reconfigured to adapt to the increasing tower height during making of the tower. The support structure may comprise rigid legs, e.g. telescopic legs, and/or wires attached to form a cable stayed tower. For example, the wires are attached to winches that are temporarily fixed to the ground. When the tower assembly device crawls upwards the winches give out wire and then holds firm when the device is in operation.
In a second aspect, the disclosure provides a wind turbine nacelle comprising a main unit housing a main frame supporting a rotor assembly, the rotor assembly defining a rotation axis and the main unit being arranged to be mounted on the wind turbine tower via the main frame, the wind turbine further comprising at least one tower assembly device of the kind described above and connected to the main unit and extending below the main frame.
The tower assembly device comprises:
The tower assembly unit may be releasable from the main unit to allow reuse of the tower assembly unit for construction of different wind turbines.
The tower assembly unit may comprise any of the features mentioned already relative to the first aspect of the disclosure.
In accordance with the second aspect of the disclosure, the wind turbine nacelle may be prepared in advance. This could be either at a factory site or on the ground at the site where the wind turbine is under construction. Since the nacelle is pre-fitted with an assembly device, the construction and assembly work around the tower can be minimized which supports efficient wind turbine manufacturing.
In a third aspect, the disclosure provides a method of constructing a wind turbine generator at a construction site by use of an assembly device of the kind described relative to the first aspect of the disclosure. The method comprises:
The nacelle may form a main unit and at least one auxiliary unit, the main unit and the auxiliary unit being separate parts, and the main frame may form part of the main unit. The nacelle may further comprise a drive train and any operative component for converting wind energy into electrical power for a power grid. According to the method, the main unit and the auxiliary unit are assembled after the tower unit is joined to the free end of the tower, and optionally any other component of the drive train or energy conversion may be assembled after the tower unit is joined to the free end of the tower.
To facilitate easier transportation, steel blanks, i.e. plate shaped elements are transported to the construction site. Such blanks can be stacked on a cargo vessel such as a truck or train, and may easily be transported. At the construction site, the blanks are curled up such that opposite free ends of the blanks are joined to form tubular units. Such units are typically referred to in the literature as “cans”, and the opposite free ends are typically joined by welding. The tower unit can be made with a single plate height or consist of a number of single height units stacked and welded to each other to constitute a taller tower unit to be inserted in the unit receiving structure.
The tower, the nacelle, and/or the tower assembly device may comprise a damper to dampen vortex-induced vibrations.
In the following, embodiments of the disclosure will be described in further details with reference to the drawing in which:
The detailed description and specific examples, while indicating embodiments, are given by way of illustration only, since various changes and modifications within the spirit and scope of this disclosure will become apparent to those skilled in the art from this detailed description.
The tower is typically assembled from a number of round sections of steel extending between flanges which are bolted to flanges of adjacent sections. Each section is often made from round units, also known as cans, which are welded to adjacent units. The cross section of the tower is often tapered in the direction from the bottom towards the top of the tower.
In an embodiment, the surface of the tower 33 has indentations or protrusions that provide an interface for the claw or clamp elements to attach to.
At a top end 24 of the chassis 21, the device 20 comprises a nacelle interface 25. The nacelle interface 25 is illustrated in further details in
The chassis 21 extends between the tower interface 23 and the nacelle interface 25, and the nacelle interface 25 is thereby arranged to place the nacelle above a free end of a wind turbine tower.
A lifting structure (not shown) is configured to move the nacelle interface relative to the tower interface to create a space 26 (illustrated by the bracket) between the free end of the wind turbine tower and the nacelle interface. The lifting structure may e.g. be comprised in the aforementioned strand jack lifting system.
The device is arranged to receive tower units 53 which are to be attached to the tower. The arrow 27 indicates a window in which a unit receiving structure can insert tower units into the space 26. The unit receiving structure may include the illustrated hoisting structure 28 by which the tower unit can be lifted from ground and inserted into the space. In the illustrated embodiment, the hoisting structure is constituted by a cantilever beam with a pulley structure mounted on a trolley 29. In the illustrated external position of the trolley, the tower units can be hoisted along an external tower surface until reaching a sideways window into the space. In this altitude, the trolley is moved as illustrated by the arrow 27 and the tower unit enters into the space.
The tower assembly structure includes an assembly structure, in this embodiment constituted by the welding assembly comprising one or more welding robots with welding guns 30 fixed to a rotating assembly allowing the welding robots to rotate about the outer surface of the tower. By this structure, the tower unit can be welded to the free end of the tower. Additionally or alternatively, the assembly structure may comprise any suitable structure for bolting, riveting, gluing or other ways of assembly.
In an embodiment the chassis 21 comprises a platform (not illustrated) from where personnel can perform welding manually and/or inspect the welding performed by the welding robots.
In the space, the tower unit is lowered onto the free end of the tower, and an internal tower assembly structure joins the tower unit to the free end of the tower. Particularly, the tower assembly structure may include the welding assembly mentioned previously.
In one embodiment, the encapsulation comprises air cushions or bellow structures 62 at the top end 24 and at the bottom end 23. These cushion or bellow structures are configured to expand into contact with an outer surface of the tower or tower unit and thereby provide a sealed enclosed area in which temperature and humidity can more easily be controlled.
A partition wall formed by the inflatable bellow 63 which can be inflated into contact with an outer surface of the tower may separate the enclosed area into an upper enclosed area 64 and a lower enclosed area 65.
The assembly structure, illustrated by the welding guns 30, may be housed in the upper enclosed area 64, and the lower enclosed area 65 may contain a surface treatment unit for treatment of the wind turbine tower. In one example, such a surface treatment unit includes abrasive cleaning equipment, painting equipment and paint curing equipment etc. In this way, a completely finished and surface treated interface between each tower unit may be created in the enclosed area.
One or more platforms (not shown) for personnel working in the device may be provided at appropriate locations to allow access to the tower structure as needed.
In
When the tower is finished, the main unit is fixed to the tower via a yaw assembly. Subsequently, the nacelle is completed by lifting further nacelle components and attaching them to the main unit. In one such embodiment, the nacelle is constituted by a main unit and one or more auxiliary units, each having e.g. the shape of a standard container for shipping.
The partly assembled nacelle can for example be used for equipment storage, storage of supplies, i.e. surface treatments, as a temporary workshop and/or accommodation for personnel during construction of the tower structure.
In accordance with the embodiment where the nacelle is constituted by a main unit and one or more auxiliary units, the assembly procedure may include that a first tower unit is installed on a foundation. The tower interface of an assembly device described herein is attached to the first tower unit, and a main unit of the nacelle is attached to the nacelle interface of the assembly device. The internal crane 72 on the main unit is used for hoisting tower units and the assembly device is used for assembling the tower units to the free end of the tower, and to lift the main unit to create space for the tower units to be inserted between the free end and the main unit. When the tower is finished, the crane 72 is used as indicated on
One or more of the auxiliary units may contain separate cranes which, once the auxiliary unit is mounted on the main unit, can be used for lifting components from ground to the nacelle, e.g. for final assembly of the wind turbine or during maintenance.
In any of the embodiments illustrated in
In one embodiment, the crane 91 is used for lifting the tower unit 53 from the ground and thereby for assisting the unit receiving structure. In this embodiment, the unit receiving structure may be reduced simply to an opening into the space 26 through which opening, the crane 91 may lift the tower unit 53. In this embodiment, the wind turbine tower assembly device may comprise no lifting capacity for lifting the tower units.
In other embodiments, the crane 91 is used for supporting the lifting of the tower unit 53 from the ground, and the unit receiving structure may comprise complementary support, lifting or handling means configured for supporting entry of the tower unit into an opening into the space 26. In this procedure, the crane 91 may e.g. provide a vertical lift and support, lifting or handling means forming part of the unit receiving structure may e.g. provide horizontal movement of the tower unit into the space 26.
| Number | Date | Country | Kind |
|---|---|---|---|
| PA 2020 70296 | May 2020 | DK | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/DK2021/050143 | 5/6/2021 | WO |
