WIND TURBINE NACELLE

Abstract

A wind turbine nacelle configured for mounting on a wind turbine tower and for supporting a rotor assembly, the nacelle comprising at least a first and a second nacelle module. The first nacelle module comprises a first frame structure and a main bearing system for a main shaft of the rotor assembly, and the second nacelle module comprises a second frame structure and a drive train system for the wind turbine. When the nacelle is mounted on the wind turbine tower, the main bearing system is supported by the wind turbine tower, and the drive train system is attached to the main bearing such that the weight of the drive train system is transferred to the main bearing system and thereby to the wind turbine tower. Further, the first frame structure is configured to support the main bearing system during transportation and prior to mounting of the nacelle, and the second frame structure is configured to support the drive train system during transportation and prior to mounting of the nacelle, and the first and second frame structures form a load carrying structure of a first and a second shipping freight container such that the first and second nacelle module can be transported as shipping freight containers. When the nacelle is mounted on the wind turbine tower, the first and second frame structures may be placed side by side in a direction along a rotational axis of the wind turbine rotor and may be oriented such as to have a length extending transversely to a rotational axis of the wind turbine rotor.

Claims

1. A wind turbine nacelle configured for mounting on a wind turbine tower and for supporting a rotor assembly, the nacelle comprising at least a first and a second nacelle module, the first nacelle module comprising a first frame structure and a main bearing system for a main shaft of the rotor assembly, and the second nacelle module comprising a second frame structure and a drive train system for the wind turbine, wherein, when the nacelle is mounted on the wind turbine tower, the main bearing system is supported by the wind turbine tower, and the drive train system is attached to the main bearing such that the weight of the drive train system is transferred to the main bearing system and thereby to the wind turbine tower, wherein the first frame structure is configured to support the main bearing system during transportation and prior to mounting of the nacelle, and wherein the second frame structure is configured to support the drive train system during transportation and prior to mounting of the nacelle, and wherein the first and second frame structures form a load carrying structure of a first and a second shipping freight container such that the first and second nacelle module can be transported as shipping freight containers.

2. The wind turbine nacelle according to claim 1, wherein, when the nacelle is mounted on the wind turbine tower, the first and second frame structures are placed side by side in a direction along a rotational axis of the wind turbine rotor.

3. The wind turbine nacelle according to claim 1, wherein the first and second frame structures are oriented such as to have a length extending transversely to a rotational axis of the wind turbine rotor when the nacelle is mounted on the wind turbine tower.

4. The wind turbine nacelle according to claim 1, wherein the first frame structure has a length, a width, and a height, and the second frame structure has the same length and height as the first frame structure, and wherein the first frame structure and the second frame structure are placed corner to corner in the nacelle when mounted on the wind turbine tower.

5. The wind turbine nacelle according to claim 1, wherein, when the nacelle is mounted on the wind turbine tower, the second frame structure is attached to and supported by the first frame structure, and wherein the first frame structure is supported by the tower.

6. The wind turbine nacelle according to claim 1, wherein the first nacelle module is placed in between the rotor assembly and the second nacelle module.

7. The wind turbine nacelle according to claim 1, wherein the second nacelle module is placed in between the rotor assembly and the first nacelle module.

8. The wind turbine nacelle according to claim 1, further comprising a third nacelle module comprising a third frame structure, which is placed side by side to the first or the second frame structure when the nacelle is mounted on the wind turbine tower.

9. The wind turbine nacelle according to claim 8, where the third frame structure is placed side by side to the second frame structure in a direction along the rotational axis of the wind turbine rotor when the nacelle is mounted on the wind turbine tower.

10. The wind turbine nacelle according to claim 8, wherein the third frame structure is configured to support a generator during transportation and prior to mounting of the nacelle, and wherein the generator, when the nacelle is mounted on the wind turbine tower, is attached to the drive train system such that the weight of the generator is transferred to the drive train system and to the main bearing system and thereby to the wind turbine tower.

11. The wind turbine nacelle according to claim 8, wherein the third frame structure has a length smaller than the length of the first or the second frame structures.

12. The wind turbine nacelle according to claim 1, wherein the first nacelle module further comprises at least a part of a yawing arrangement which is supported by the first frame structure during transportation and prior to mounting of the nacelle, and where the yawing arrangement part is supported by the wind turbine tower when the nacelle is mounted on the wind turbine tower.

13. The wind turbine nacelle according to claim 1, wherein the first nacelle module further comprises a bed plate which is supported by the first frame structure during transportation and prior to mounting of the nacelle, and where the bed plate is supported by the wind turbine tower when the nacelle is mounted on the wind turbine tower.

14. The wind turbine nacelle according to claim 13, wherein the first nacelle module comprises further wind turbine components such as a lubrication system or a control system mounted on the bed plate.

15. The wind turbine nacelle according to claim 1, wherein the drive train system is resiliently suspended in the second frame structure during transportation.

16. The wind turbine nacelle according to claim 1, wherein the drive train system is suspended in the second frame structure by suspension means configured for movement of the drive train system relative to the second frame structure during assembly of the nacelle.

17. The wind turbine nacelle according to claim 1, wherein the mounted nacelle further comprises a cover attached to at least the first and the second frame structures.

18. The wind turbine nacelle according to claim 1, wherein the first and/or the second frame structures have a height of 2.591 m or 2.896 m, a width of 2.438 m, and a length of any of 6.058 m, 12.192 m, or 13.716 m.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In the following different embodiments of the invention will be described with reference to the drawings, wherein:

[0043] 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,

[0044] FIG. 2 shows a top view of a wind turbine nacelle as assembled according to an embodiment of the invention and a top view of the frame structure of one of the nacelle modules,

[0045] FIG. 3 shows a sketch of the assembled wind turbine nacelle of FIG. 2 in a perspective view,

[0046] FIG. 4 shows an embodiment of a frame structure of a nacelle module according to an embodiment of the invention,

[0047] FIG. 5 shows an embodiment of a second nacelle module as seen from a side, and

[0048] FIG. 6 is a sketch of the exchange of a nacelle module of wind turbine nacelle according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0049] FIG. 1 shows 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 forms the rotor assembly and 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 is placed the different wind turbine components such as a drive train system 6. The nacelle 2 is described in further detail below with reference to FIGS. 2-6.

[0050] FIG. 2 shows to the left a top view of a wind turbine nacelle 2 as assembled according to an embodiment of the invention, and to the right a top view of the frame structure 210 of one of the nacelle modules. The nacelle comprises a first 201, a second 202, and a third 203 nacelle module each comprising a frame structure 210. In this embodiment, the first, second and third frame structures 210 are placed side by side and corner to corner in a direction along the rotational axis of the wind turbine rotor and oriented with their length L, 211 transversely to the rotational axis. The three frame structures 210 here have the same length L, 211, width W, 212, and height H, 213.

[0051] The nacelle modules each comprise different wind turbine components. The first nacelle module 201 comprises a main bearing system 221 for a main shaft of the rotor assembly 4, and the second nacelle module comprises a drive train system 6 attached to the main bearing system 221. The drive train is mounted in the nacelle such that the weight of the drive train system is transferred to the main bearing system and thereby to the wind turbine tower, and the main bearing system is supported by the wind turbine tower. The wind turbine tower 3 is not shown in FIG. 2, but the yawing arrangement 230 also being a part of the first nacelle module 201 is indicated by the dashed lines. The first nacelle module 201 here further comprises a controller 231, a power supply 232, and a lubrication system 233. The second nacelle module 202 comprises a cooling system 240, and the third nacelle module comprises a generator 250 and a converter 251. The generator 250 is connected to the drive train system 6 when the nacelle is assembled.

[0052] During transportation and prior to mounting of the nacelle each of the three frame structures 210 are configured to support the wind turbine components placed within them. Further, the first, second, and third frame structures 210 each form a load carrying structure of a shipping freight container. In this way each of the nacelle modules can be transported and handled as shipping freight containers. Each of the three frame structures in the nacelle of FIG. 3 have outer dimensions, i.e. length L, 211, width W,212, and height H, 213 of a 20′ shipping freight container of 6.058 m, 2.438 m, and 2.591 m, respectively.

[0053] FIG. 3 shows a sketch of the assembled wind turbine nacelle 2 of FIG. 2 in a perspective view. Here the three frame structures 210 of the nacelle modules 201, 202, 203 are connected at least in the corners 300 as indicated in the figure. The assembled nacelle 2 comprises a cover 301 attached at least to the sides of the assembled nacelles and wherein the frame structures are used for attachment of the cover 301.

[0054] FIG. 4 shows in a perspective view an embodiment of a frame structure 210 of a nacelle module 201, 202, 203 according to an embodiment of the invention. The frame structure 210 here is a box-like structure and forms the load carrying structure of a shipping freight container. The frame structure comprises four bottom rails 401, four corner posts 402, and four top rails 403 connected in eight corner fittings 300. The frame structures 210 may further comprise a bed plate and cross members or struts to increase the stability and the strength of the frame structure.

[0055] FIG. 5 shows an embodiment of the second nacelle module 202 as seen from a side and along the rotational axis of the wind turbine. The second nacelle module 202 comprises a frame structure 210 and the drive train system 6 which is placed such as to be supported by the frame structure 210 during the transportation and prior to assembly of the nacelle. The drive train system 6 is here suspended by means of a number of struts 500 connecting the drive train system 6 to the frame structure 210. The drive train system may also be placed and supported by bottom rails or a bed plate (not shown) of the frame structure. The nacelle module 202 may also comprise further wind turbine components 501 such as a lubrication system 233. These components are likewise supported by the frame structure during transportation for example by being attached or mounted onto one or more of the corner posts 402 or to a bottom rail or a bed plate of the frame structure. When assembled, the drive train system 6 is attached to the main bearing system of the first nacelle module. The support of the drive train by the frame structure may then be partly detached or loosened. Alternatively or additionally the load transfer may be shifted such that the frame structure is partly or completely supported by and hanging on the drive train system when the nacelle is assembled. The same applies for the main bearing system in the first nacelle module.

[0056] FIG. 6 is a sketch of how one or more nacelle modules 202, 203 may be lowered down to the ground for repair or exchange by means of a crane 600 which in this example is mounted on top of the wind turbine tower 3 or on top of the first nacelle module 201. The crane could likewise be a stand-alone crane. The sketches in FIG. 6 outline the method both as seen from the side and as seen from above. If for example the gear system is to be exchanged, this may be obtained by lowering first the third 203 and then the second nacelle module 202a to the ground. The wind turbine may advantageously be yawed in between the operations to thereby place the nacelle modules at different positions around the tower 3. The frame structure of each nacelle module forming a load carrying structure of a shipping freight container then advantageously comprises the strength for the hoisting operations. A new second nacelle module 202b with a new gear system can then be lifted and mounted to the first nacelle module 201, followed by the third nacelle module 203.

[0057] While preferred embodiments of the invention have been described, it should be understood that the invention is not so limited and modifications may be made without departing from the invention. The scope of the invention is defined by the appended claims, and all devices that come within the meaning of the claims, either literally or by equivalence, are intended to be embraced therein.