Abstract
A nacelle for a wind turbine and a method for erecting a wind turbine are disclosed. The nacelle comprises a main unit arranged to be connected to a wind turbine tower, via a yawing arrangement, and at least one side unit mounted along a side of the main unit in such a manner that direct access is allowed between the main unit and the side unit(s), each side unit accommodating at least one wind turbine component, and at least one side unit being capable of carrying the wind turbine component(s) accommodated therein. The main unit and at least one of the side unit(s) are distributed side by side along a substantially horizontal direction which is substantially transverse to a rotational axis of a rotor of the wind turbine. A sufficient interior space of the nacelle is obtained while allowing the nacelle to be transported due to the modular construction. The weight of the wind turbine components is arranged close to the tower due to the transversal arrangement of the side unit(s) relative to the main unit.
Claims
1. A nacelle for a wind turbine, comprising: a main unit arranged to be connected to a wind turbine tower, via a yawing arrangement, at least one side unit mounted along a side of the main unit in such a manner that direct access is allowed between the main unit and the at least one side unit, the at least one side unit accommodating at least one wind turbine component, and the at least one side unit being capable of carrying the at least one wind turbine component accommodated therein, wherein the main unit and the at least one side unit are distributed side by side along a substantially horizontal direction which is substantially transverse to a rotational axis of a rotor of the wind turbine.
2. The nacelle according to claim 1, wherein the at least one side unit is mounted along a side of the main unit in such a manner that a common interior space of the nacelle is defined by the main unit and the at least one side unit.
3. The nacelle according to claim 1, wherein the at least one side unit accommodates the at least one wind turbine component arranged in a closed compartment, said closed compartment being arranged in the at least one side unit.
4. The nacelle according to claim 3, wherein the closed compartment provides electromagnetic shielding for the at least one wind turbine component arranged in the compartment.
5. The nacelle according to claim 3, wherein the compartment is provided with a door allowing access to the at least one wind turbine component arranged in the compartment.
6. The nacelle according to claim 1, wherein the at least one side unit is mounted in such a manner that the at least one side unit can be moved directly between the mounted position at the nacelle and a base level of the wind turbine.
7. The nacelle according to claim 1, wherein the at least one side unit comprises a supporting structure.
8. The nacelle according to claim 1, wherein the main unit comprises at least one beam, the at least one beam being connectable to lifting equipment for mounting and/or demounting the main unit on/from the wind turbine tower.
9. The nacelle according to claim 8, wherein the at least one beam forms part of a hoisting arrangement for hoisting and/or lowering the at least one wind turbine component and/or the at least one side unit to/from the nacelle.
10. The nacelle according to claim 8, wherein the at least one beam is adapted to carry the at least one wind turbine component accommodated in the at least one side unit.
11. The nacelle according to claim 1, wherein the least one wind turbine component accommodated by the at least one side unit is a transformer.
12. The nacelle according to claim 11, wherein the at least one side unit accommodating a transformer further accommodates a converter.
13. The nacelle according to claim 12, wherein the converter is arranged adjacent to the transformer and adjacent to a generator of the wind turbine.
14. The nacelle according to claim 11, wherein the transformer is arranged at a position near the yawing arrangement.
15. The nacelle according to claim 1, wherein the at least one wind turbine component accommodated by the at least one side unit is an on-board crane.
16. The nacelle according to claim 1, said nacelle comprising at least two side units, a first side unit accommodating one or more electrical wind turbine components, and a second side unit accommodating one or more liquid containing wind turbine components.
17. The nacelle according to claim 1, wherein the at least one side unit extends substantially along the entire length of the main unit.
18. The nacelle according to claim 1, wherein an interface defined by the main unit towards the at least one side unit is connectable to a corresponding interface of a crane, upon removal of the side unit.
19. The nacelle according to claim 1, wherein the at least one side unit is adapted to accommodate the at least one wind turbine component during transport from a manufacturing location to a wind turbine site.
20. The nacelle according to claim 19, wherein the at least one side unit comprises a connector allowing a transportation cover to be attached to the at least one side unit.
21. The nacelle according to claim 1, further comprising a cover covering at least part of the main unit and at least part of at least one of the at least one side unit.
22. The nacelle according to claim 1, further comprising a main cover covering at least part of the main unit, and at least one side cover covering at least part of a side unit.
23. The nacelle according to claim 21, wherein at least one cover is provided with at least one opening allowing passage of wind turbine components.
24. The nacelle according to claim 1, wherein at least one side unit is mounted along a first side of the main unit and a cooling device having a cooling area extends from a second side of the main unit, the second side being arranged opposite to the first side.
25. The nacelle according to claim 24, comprising a cooling cover having at least one inner face, the cooling device being enclosed by a face of the second side of the main unit and the inner face of the cover.
26. A wind turbine comprising a nacelle according to claim 1.
27. A method for erecting a wind turbine comprising a nacelle comprising: erecting a wind turbine tower, mounting a main unit on the wind turbine tower, via a yawing arrangement, hoisting at least one side unit, along with at least one wind turbine component accommodated therein, to a position adjacent to the main unit, and connecting the at least one side unit to the main unit in such a manner that a common interior nacelle space is defined by the main unit and the at least one side unit.
28. The method according to claim 27, further comprising transporting the at least one side unit accommodating at least one wind turbine component from a manufacturing location to a wind turbine site, prior to performing the step of hoisting the at least one side unit.
29. The method according to claim 27, wherein the step of connecting the side unit to the main unit is performed in such a manner that the main unit and the at least one side unit are distributed side by side along a substantially horizontal direction which is substantially transverse to a rotational axis of a rotor of the wind turbine.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0060] The invention will now be described in further detail with reference to the accompanying drawings, in which
[0061] FIG. 1 is a perspective view of a wind turbine having a nacelle according to an embodiment of the invention mounted at a tower thereof,
[0062] FIG. 2 is a perspective view of a nacelle according to a first embodiment of the invention,
[0063] FIG. 3 is a perspective view of the nacelle of FIG. 2, wherein wind turbine components accommodated in the nacelle are visible,
[0064] FIG. 4 is a perspective view of the nacelle of FIG. 2, wherein a side module has been replaced by a crane,
[0065] FIG. 5 is a side view of the nacelle according to a second embodiment of the invention,
[0066] FIG. 6 is a top view of the nacelle of FIG. 5,
[0067] FIG. 7 is a perspective view of a wind turbine comprising a nacelle according to a third embodiment of the invention,
[0068] FIG. 8 shows a detail of the nacelle illustrated in FIG. 7,
[0069] FIG. 9 is a perspective view of a nacelle according to a fourth embodiment of the invention,
[0070] FIGS. 10 and 11 illustrate two side units for use in a nacelle according to an embodiment of the invention,
[0071] FIGS. 12 and 13 illustrate two side units for use in a nacelle according to an alternative embodiment of the invention,
[0072] FIGS. 14 and 15 are perspective views of side units comprising a transportation cover,
[0073] FIG. 16 is a schematic view of a nacelle according to a fifth embodiment of the invention,
[0074] FIG. 17 is a schematic view of a nacelle according to a sixth embodiment of the invention, and
[0075] FIGS. 18-21 illustrate a nacelle according to a seventh embodiment of the invention.
DETAILED DESCRIPTION OF THE DRAWINGS
[0076] FIG. 1 is a perspective view of a wind turbine 1 having a nacelle 2 according to an embodiment of the invention mounted on a tower 3 thereof. A hub 4 carrying three rotor blades 5 is mounted at the nacelle 2. A top part of the nacelle 2 has been removed for the sake of clarity, thereby revealing the interior parts of the nacelle 2. Inside the nacelle 2 a gear arrangement 6 is accommodated. The nacelle 2 is described in further detail below with reference to FIGS. 2-6.
[0077] FIG. 2 is a perspective view of a nacelle 2 according to a first embodiment of the invention. A hub 4 is mounted on the nacelle 2, and is provided with three blade flanges 7, each being adapted to be connected to a corresponding flange of a rotor blade (not shown). The nacelle 2 comprises a main unit 8 and two side units 9a, 9b. A cooling area 10 is arranged on top of the nacelle 2.
[0078] The main unit 8 is mounted on a tower 3 via a yawing arrangement (not shown), allowing the nacelle 2 to rotate in order to direct rotor blades carried by the hub 4 into the wind.
[0079] FIG. 3 is a perspective view of the nacelle 2 of FIG. 2. In FIG. 3 the outer walls of the nacelle 2 are transparent, thereby revealing the interior parts of the nacelle 2 and the wind turbine components accommodated therein. The main unit 8 accommodates a main bearing unit 11, a gear arrangement 6 and a generator 12, arranged sequentially behind the hub 4, along a direction defined by the rotational axis of the hub 4.
[0080] A first side unit 9a accommodates a transformer unit 13, a gear oil unit 16 and a cooling unit 15. A second side unit 9b accommodates a converter unit 14 and a hydraulic unit 17.
[0081] The side units 9a, 9b are each mounted along a side of the main unit 8 in such a manner that one side unit 9a is mounted along a left side of the main unit 8 and the other side unit 9b is mounted along a right side of the main unit 8, as seen in a direction along a rotational axis of the hub 4 from the hub 4 towards a rear wall of the main unit 8. Accordingly, the nacelle 2 with the side units 9a, 9b mounted on the main unit 8 is wider than the main unit 8, while the length of the nacelle 2 is essentially identical to the length of the main unit 8. It is an advantage that the side units 9a, 9b are mounted in this manner relative to the main unit 8, because the weight of the wind turbine components 13, 14, 15, 16, 17 accommodated in the side units 9a, 9b is thereby arranged relatively close to the tower 3. Since the tower 3 carries the loads arising from the nacelle 2 and everything accommodated therein, the torque loads occurring in the nacelle 2 and in the tower 3 are reduced when the side units 9a, 9b are arranged as illustrated in FIGS. 2 and 3, as compared to a situation where additional units are arranged one behind the other along a direction defined by the rotational axis of the hub 4.
[0082] It is clear from FIG. 3 that the side units 9a, 9b are connected to the main unit 8 in such a manner that the interior parts of the main unit 8 and the side units 9a, 9b form one common interior space. Accordingly, once the side units 9a, 9b have been mounted on the main unit 8, a wide nacelle 2 with a large interior space for accommodating various components is provided. However, this is obtained without the drawbacks involved with transporting a nacelle with the same dimensions in one piece, because the nacelle 2 is made from the main unit 8 and the side units 9a, 9b, which are transported individually to the operating site.
[0083] Each of the side units 9a, 9b can be lowered directly from the position shown in FIGS. 2 and 3 towards the ground, because no beams or other structural parts protrude from the main unit 8 towards the side units 9a, 9b at a floor level of the nacelle 2. Similarly, the side units 9a, 9b can be hoisted directly from a lower level, e.g., a ground level, to the mounted position illustrated in FIGS. 2 and 3, e.g., during erection of the wind turbine. This is an advantage, because it allows the side units 9a, 9b, including the wind turbine components 13, 14, 15, 16, 17 accommodated therein, to be hoisted to or lowered from the mounted position by means of hoisting equipment (not shown) arranged in the nacelle 2. Furthermore, it allows the total weight which needs to be hoisted to the position at the top of the tower 3 to be divided into smaller portions, and the requirements to the lifting equipment used during erection of the wind turbine are thereby reduced.
[0084] FIG. 4 is a perspective view of the nacelle 2 of FIG. 2. However, in FIG. 4 one of the side units (9b in FIG. 3) has been lowered from the nacelle 2. Instead a crane 18 has been hoisted to the nacelle 2 and mounted on the main unit 8, using the same interface which was used for mounting the side unit 9b to the main unit 8 in the situation illustrated in FIG. 3. The crane 18 is of a size which does not allow it to be permanently accommodated in the nacelle 2. However, it may sometimes be necessary or desirable to have such a crane 18 present in or at the nacelle 2. The crane 18 may, e.g., be used for moving some of the larger wind turbine components accommodated in the nacelle 2, e.g., the gear arrangement 6 or the generator 12. It is an advantage that the design of the nacelle 2 allows a larger and more powerful crane 18 to be available in the nacelle 2 in an easy manner, i.e., simply by lowering a side unit 9b from the nacelle 2 and hoisting the crane 18 to the position where the side unit 9b was previously mounted, because this allows easy access to such a crane 18 without the disadvantages relating to space consumption by having the crane 18 installed permanently in the nacelle 2.
[0085] FIG. 5 is a side view of a nacelle 2 according to a second embodiment of the invention, and FIG. 6 is a top view of the nacelle 2 of FIG. 5. In FIG. 6 the roof of the nacelle 2 has been removed in order to reveal the interior of the nacelle 2 and the wind turbine components accommodated therein. These components have already been described above with reference to FIGS. 3 and 4, and will therefore not be described in further detail here. The embodiment illustrated in FIGS. 5 and 6 is very similar to the embodiment illustrated in FIGS. 2-4. However, in FIGS. 5 and 6, the converter unit 14 is accommodated in the side unit 9a which also accommodates the transformer unit 13. Thus, the electrical wind turbine components 13, 14 are accommodated in the first side unit 9a, and the liquid containing wind turbine components 16, 17 are accommodated in the second side unit 9b. This is an advantage, because the risk that the electrical wind turbine components 13, 14 get into contact with liquid is thereby reduced. Furthermore, it is an advantage that the converter unit 14 is arranged immediately next to the transformer 13 as well as immediately next to the generator 12, because the current paths between these components are thereby minimized as described in detail above.
[0086] In FIG. 6 two lifting beams 19 are visible. The lifting beams 19 are arranged transversally across the main unit 8 of the nacelle 2. During erection of the wind turbine, the main unit 8 may be hoisted to the position on top of the tower by coupling the lifting beams 19 to lifting equipment, such as a large crane, and lifting the main unit 8 in position by means of the lifting equipment and via the lifting beams 19. Furthermore, the lifting beams 19 may be equipped with hoisting equipment used for hoisting the side units 9a, 9b and/or the wind turbine components 13, 14, 15, 16, 17 to the mounted position. Similarly, such hoisting equipment may be used for lowering the side units 9a, 9b and/or the wind turbine components 13, 14, 15, 16, 17 at a later time. Finally, the lifting beams 19 may be used for mounting one or more of the heavy wind turbine components, e.g., the transformer 13 or the converter 14 after the side unit 9a has been hoisted to the nacelle 2 and mounted on the main unit 8. In this case the weight of these wind turbine components is carried by the main unit 8 during normal operation of the wind turbine.
[0087] FIG. 7 is a perspective view of a wind turbine 1 with a nacelle 2 according to a third embodiment of the invention mounted on a tower 3 thereof. A hub 4 carrying three rotor blades 5 is mounted at the nacelle 2. The nacelle 2 is shown without a cover or top part in order to reveal the interior parts of the nacelle 2.
[0088] The nacelle 2 comprises a main unit 8 and two side units 9a, 9b, similarly to the embodiment shown in FIG. 2. A main bearing unit 11 and a gear arrangement 6 are accommodated in the main unit 8. Each of the side units 9a, 9b accommodates three closed compartments 20. Each of the closed compartments 20 accommodates one or more wind turbine components, such as generator, transformer, converter, cooling devices, oil units, hydraulic units, etc. Since the wind turbine components are arranged in the closed compartments 20, it is possible to customize various environmental parameters, such as temperature, humidity, moisture, etc., to the wind turbine component(s) accommodated in a specific closed compartment 20, without taking requirements of other wind turbine components into consideration. Furthermore, it is easier to control the environment inside a closed compartment 20 than in the entire interior part of the nacelle 2, because the volume of one of the closed compartments 20 is significantly smaller than the volume of the entire interior part of the nacelle 2.
[0089] Furthermore, the wind turbine components can be arranged in the closed compartments 20 at the manufacturing site and transported to the operating site of the wind turbine 1 in the closed compartments 20, and the closed compartments 20, along with the wind turbine components accommodated therein, can be mounted in the nacelle 2. This makes it easy to install the wind turbine components in the nacelle 2.
[0090] FIG. 8 shows a detail of the nacelle 2 illustrated in FIG. 7. Part of the main unit 8, accommodating the gear arrangement 6, and three closed compartments 20 are visible. The closed compartments 20 are provided with openings 21 allowing access to the interior parts of the closed compartments 20. The openings 21 may be provided with doors or hatches (not shown) which may be closed during normal operation of the wind turbine, thereby substantially enclosing the wind turbine components accommodated in the closed compartments 20. When access to the wind turbine components is required, e.g., in order to perform inspection, maintenance or replacement of one or more wind turbine components, the door or hatch of the relevant closed compartment 20 can be opened, thereby allowing access to the wind turbine components accommodated in the closed compartment 20, via the opening 21. FIG. 9 is a perspective view of a nacelle 2 according to a fourth embodiment of the invention. The nacelle 2 comprises a main unit and two side units, similarly to the embodiments described above. In the nacelle 2 shown in FIG. 9, a common upper cover 22 and a common lower cover 23 enclose the main unit as well as the side units. Accordingly, the main unit and the side units are not visible in FIG. 9.
[0091] FIGS. 10 and 11 show side units 9a, 9b for use in a nacelle according to an embodiment of the invention. In FIG. 10 each of the side units 9a, 9b is provided with a transportation cover 24, covering three sides of the side unit 9a, 9b. In FIG. 11 each side unit 9a, 9b is further provided with a side cover 25 covering the remaining three sides of the side unit 9a, 9b. Thus, it is clear from FIG. 11 that the transportation cover 24 and the side cover 25 in combination completely enclose the side unit 9a, 9b. The side cover 25 is permanently mounted on the side unit 9a, 9b in the sense that it is mounted on the side unit 9a, 9b at the manufacturing site, and it forms part of the outer walls of the nacelle when the side unit 9a, 9b is mounted on a main unit.
[0092] The transportation cover 24, on the other hand, is only mounted on the side unit 9a, 9b during transportation of the side unit 9a, 9b in order to protect the side unit 9a, 9b during the transportation. Thus, the transportation cover 24 should be removed before the side unit 9a, 9b is mounted on a main unit, thereby assembling the nacelle.
[0093] FIGS. 12 and 13 show side units 9a, 9b for use in a nacelle according to an alternative embodiment of the invention. The side units 9a, 9b are provided with transportation covers 24 and side covers 25, similarly to the side units 9a, 9b shown in FIGS. 10 and 11. However, in FIGS. 12 and 13, the transportation covers 24 cover two sides of each side unit 9a, 9b, and the side covers 25 cover four sides of each side unit 9a, 9b.
[0094] FIG. 14 is a perspective view of a side unit 9 for use in a nacelle according to an embodiment of the invention. The side unit 9 is provided with a side cover 25 covering five sides of the side unit 9, thereby leaving only one side of the side unit 9 open. The open side forms an interface of the side unit 9 towards a main unit, and a common interior space can thereby be formed by the side unit 9 and the main unit when they are assembled to form the nacelle.
[0095] A transportation cover 24 is also illustrated in FIG. 14, and it is indicated that the transportation cover 24 can be mounted on the side unit 9 in such a manner that it covers the open side of the side unit 9. Thus, as described above, the transportation cover 24 can be mounted on the side unit 9 at the manufacturing site, and the side unit 9 can be transported from the manufacturing site to the operating site of the wind turbine, or to an assembly site of the nacelle, thereby protecting the side unit 9 and any parts or items arranged in the interior part of the side unit 9 during transportation. Prior to assembling the nacelle, the transportation cover 24 is removed.
[0096] FIG. 15 is a perspective view of a side unit 9 which is similar to the side unit 9 illustrated in FIG. 14. The remarks set forth above with reference to FIG. 14 are therefore equally applicable here. However, in the side unit 9 of FIG. 15, a closed compartment 20 is accommodated in the side unit 9. Thus, when the side unit 9 is transported from the manufacturing site to the operating site of the wind turbine, or to an assembly site of the nacelle, the closed compartment 20, and any wind turbine components accommodated therein, is transported along.
[0097] FIG. 16 is a schematic view of a nacelle 2 according to a fifth embodiment of the invention. The nacelle 2 comprises a main unit 8 and two side units 9a, 9b. The main unit 8 and the side units 9a, 9b are shown detached from each other, but it is indicated that the side units 9a, 9b can be mounted on opposing sides of the main unit 8. Thereby a nacelle 2 similar to the nacelle illustrated in FIG. 2 is obtained.
[0098] FIG. 17 is a schematic view of a nacelle 2 according to a sixth embodiment of the invention. The nacelle 2 comprises a main unit 8 and four side units 9a, 9b, 9c, 9d. The main unit 8 and the side units 9a, 9b, 9c, 9d are shown detached from each other, but it is indicated that the side units 9a, 9b, 9c, 9d can be mounted on the main unit 8 with two of the side units 9a, 9c being mounted along one side of the main unit 8, and two of the side units 9b, 9d being mounted along an opposing side of the main unit 8. The combined length of the side units 9a, 9c corresponds to the length of the main unit 8. Similarly, the combined length of the side units 9b, 9d corresponds to the length of the main unit 8.
[0099] FIGS. 18-21 illustrate a nacelle 2 according to a seventh embodiment of the invention. FIG. 18 is a perspective view of the nacelle 2, FIG. 19 is a top view of the nacelle 2, FIG. 20 is a front view of the nacelle 2, and FIG. 21 shows the nacelle 2 from the back.
[0100] The nacelle 2 of FIGS. 18-21 comprises a main unit 8 and a side unit 9 mounted along a side of the main unit 8. A cooling device 26 is mounted on a side of the main unit 8 which is arranged opposite to the side having the side unit 9 mounted thereon. The cooling device 26 defines a cooling area which extends from the main unit 8, the cooling device 26 thereby being able to exchange heat with the air surrounding the nacelle 2. Accordingly, the cooling device 26 is able to provide cooling for one or more heat producing components of the nacelle 2, such as a generator, a transformer, a gear box, a frequency converter, etc.
[0101] A cooling cover 27 is arranged to partly cover the cooling device 26. Thus the cooling device 26 is thereby enclosed by a part of the side of the main unit 8 having the cooling device 26 mounted thereon, and inner sides of the cooling cover 27.
