U.S. patent application number 13/636393 was filed with the patent office on 2013-01-10 for nacelle for a wind turbine, the nacelle comprising side units.
This patent application is currently assigned to Vestas Wind Systems A/S. Invention is credited to Mazyar Abolfazlian, Karsten Buch-Lorentsen, Erland Falk Hansen, Frank Hansen, Morten Mogensen, Henning Mortensen, Peter Haakon Porta.
Application Number | 20130011272 13/636393 |
Document ID | / |
Family ID | 44625035 |
Filed Date | 2013-01-10 |
United States Patent
Application |
20130011272 |
Kind Code |
A1 |
Mortensen; Henning ; et
al. |
January 10, 2013 |
NACELLE FOR A WIND TURBINE, THE NACELLE COMPRISING SIDE UNITS
Abstract
A nacelle (2) for a wind turbine (1) and a method for erecting a
wind turbine (1) are disclosed. The nacelle (2) comprises a main
unit (8) arranged to be connected to a wind turbine tower (3), via
a yawing arrangement, and at least one side unit (9a, 9b, 9c, 9d)
mounted along a side of the main unit (8) in such a manner that
direct access is allowed between the main unit (8) and the side
unit(s) (9a, 9b, 9c, 9d), each side unit (9a, 9b, 9c, 9d)
accommodating at least one wind turbine component (13, 14, 15, 16,
17), and at least one side unit (9a, 9b, 9c, 9d) being capable of
carrying the wind turbine component(s) (13, 4, 15, 16, 17)
accommodated therein. The main unit (8) and at least one of the
side unit(s) (9a, 9b, 9c, 9d) 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 (1).
A sufficient interior space of the nacelle (2) is obtained while
allowing the nacelle (2) to be transported due to the modular
construction. The weight of the wind turbine components (13, 14,
15, 16, 17) is arranged close to the tower (3) due to the
transversal arrangement of the side unit(s) (9a, 9b, 9c, 9d)
relative to the main unit (8).
Inventors: |
Mortensen; Henning; (Randers
SO, DK) ; Hansen; Frank; (Arden, DK) ;
Buch-Lorentsen; Karsten; (Ry, DK) ; Porta; Peter
Haakon; (Aalborg, DK) ; Hansen; Erland Falk;
(Morke, DK) ; Abolfazlian; Mazyar; (Brabrand,
DK) ; Mogensen; Morten; (Lystrup, DK) |
Assignee: |
Vestas Wind Systems A/S
Aarhus N
DK
|
Family ID: |
44625035 |
Appl. No.: |
13/636393 |
Filed: |
January 28, 2011 |
PCT Filed: |
January 28, 2011 |
PCT NO: |
PCT/EP2011/051238 |
371 Date: |
September 21, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61316152 |
Mar 22, 2010 |
|
|
|
Current U.S.
Class: |
416/244R |
Current CPC
Class: |
F03D 80/82 20160501;
Y02P 70/50 20151101; Y02E 10/72 20130101; F03D 13/20 20160501; F05B
2240/14 20130101; F05B 2240/916 20130101; F03D 80/60 20160501; F05B
2230/601 20130101; B66C 23/207 20130101; F03D 13/10 20160501; Y02E
10/728 20130101 |
Class at
Publication: |
416/244.R |
International
Class: |
F03D 11/04 20060101
F03D011/04; F03D 11/00 20060101 F03D011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 22, 2010 |
DK |
PA 2010 70117 |
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
form(s) 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 of
the 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. A 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: 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
FIELD OF THE INVENTION
[0001] The present invention relates to a nacelle for a wind
turbine, the nacelle comprising a main unit and at least one side
unit mounted on a side of the main unit. The nacelle of the present
invention is particularly suitable for use in large wind turbines.
The present invention further relates to a method for erecting a
wind turbine comprising such a nacelle.
BACKGROUND OF THE INVENTION
[0002] Over the past years there has been a tendency for wind
turbines to 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 nacelle must
also be increased in order to ensure that the nacelle is capable of
accommodating the required wind turbine components.
[0003] Wind turbines are normally transported from the location or
locations of manufacture of the individual parts to the operating
site where the wind turbine is supposed to be erected. Accordingly,
as the size of the wind turbines, and thereby the size of the
individual parts of the wind turbines, increases it becomes
increasingly difficult to transport the parts to the operating
site, and the dimensions of roads, transport vehicles etc. impose
an upper limit to the size of parts which it is possible to
transport. It is therefore desirable to be able to divide some of
the larger parts of the wind turbine into smaller modules during
transport of the parts to the operating site.
[0004] EP 2 063 119 discloses a module of a nacelle of a wind
turbine, which is separately designed, manageable and comprises a
housing part. The module is connectable to at least one further
module of the nacelle, which is also separately designed,
manageable and has a housing part. The housing part of the module
builds in the assembled status of the nacelle, which comprises
several modules, a part of the housing of the nacelle. The modules
disclosed in EP 2 063 119 are arranged one behind the other along a
direction defined by the rotational axis of the rotor of the wind
turbine. This has the consequence that some of the modules are
arranged with a relatively long distance to the tower which carries
the nacelle. Thereby the loads, in particular in the form of
torque, introduced by these modules become relatively high, and the
requirements to the strength of the construction of the nacelle as
well as of the tower are increased.
[0005] DE 10 2007 062 622 A1 discloses a wind turbine comprising a
rotor with at least one rotor blade, a tower and a nacelle mounted
on the tower. The nacelle comprises a machine house accommodating
the drive train of the wind turbine, and a housing module
accommodating electrical means of the wind turbine. The housing
module is mounted on the wind turbine via a first attachment
portion between the housing module and the machine housing, and a
second attachment portion between the housing module and the yawing
arrangement. The housing module is arranged below the machine
housing.
DESCRIPTION OF THE INVENTION
[0006] It is an object of embodiments of the invention to provide a
nacelle for a wind turbine, the nacelle being transportable using
ordinary transport means, without limiting the possible size of the
nacelle.
[0007] It is a further object of embodiments of the invention to
provide a nacelle for a wind turbine, in which the torque loads on
the nacelle are reduced as compared to prior art nacelles with the
same or similar dimensions.
[0008] It is an even further object of embodiments of the invention
to provide a method for erecting a wind turbine without the
requirement of a large crane, and without imposing limits on the
total size of the nacelle of the wind turbine.
[0009] According to a first aspect the invention provides a nacelle
for a wind turbine, the nacelle comprising: [0010] a main unit
arranged to be connected to a wind turbine tower, via a yawing
arrangement, [0011] at least one side unit mounted along a side of
the main unit in such a manner that a 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, wherein 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.
[0012] In a first aspect the present invention relates to a nacelle
for a wind turbine. Modern wind turbines comprise a tower
construction mounted on a foundation on the ground or, in case of
off-shore wind turbines, a foundation on the seabed or a floating
foundation. A nacelle is mounted on the top of the tower
construction, via a yawing arrangement, in such a manner that the
nacelle can rotate about a substantially vertical yawing axis in
order to allow the blades of the wind turbine to be directed into
the wind. The nacelle carries a rotor having a set of wind turbine
blades mounted thereon. The blades catch the wind, thereby causing
the rotor to rotate, and the rotational movements of the rotor are
transformed into electrical energy in a generator, e.g. via a gear
arrangement. The nacelle further defines a housing or enclosure
accommodating various wind turbine components, such as a generator,
one or more converters, a drive train, e.g. including a gear
arrangement, various electrical components, cooling equipment,
hydraulic components, lifting equipment, etc.
[0013] The nacelle of the invention comprises a main unit and at
least one side unit. The main unit is arranged to be connected to a
wind turbine tower via a yawing arrangement. Thus, the main unit
forms the part of the nacelle which is connected to the tower, and
it is rotatable with respect to the tower due to the yawing
arrangement, as described above.
[0014] Each side unit is 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), i.e. a side unit is a unit which is mounted
next to or along a side of the main unit. Accordingly, when the
side unit(s) is/are mounted on the main unit, personnel is allowed
to move around in an interior nacelle space which is larger than
the interior space defined by the main unit, as well as larger than
the interior space defined by each of the side unit(s), since the
personnel is allowed to gain access to the interior of the main
unit as well as to the interior of the side unit(s). This makes it
easy to accommodate the various wind turbine components in the
nacelle in a manner which allows personnel to gain access to the
components or move around the components, even if the components
have considerable sizes. Furthermore, a nacelle defining an
interior space of a sufficient size is provided, and it is possible
to transport the nacelle to the operating site by means of
traditional transport means, because the main unit and the side
unit(s) can be transported independently of each other.
[0015] Direct access between the main unit and the side unit(s)
may, e.g., be obtained by mounting at least one side of the main
unit in such a manner that a common interior space is defined by
the main unit and the side unit(s). According to this embodiment,
one large interior space is defined in the nacelle. The common
interior space of the nacelle may advantageously be formed by
leaving the sides of the main unit and the side unit(s) which face
each other completely open or almost completely open, thereby
allowing substantially free passage between the main unit and the
side unit(s).
[0016] It should be noted that even though, according to this
embodiment, a common interior space is defined by the main unit and
the side unit(s) of the nacelle of the present invention, it is not
ruled out that one or more of the wind turbine components which are
accommodated in the nacelle is/are enclosed in or covered by
separate rooms, units, racks etc. For instance, it may be desirable
to enclose a transformer in this manner, e.g. for safety
reasons.
[0017] As an alternative, direct access between the main unit and
the side unit(s) may be obtained by providing door openings in
walls defined between the main unit and the side unit(s), thereby
allowing personnel to move between the interior of the main unit
and the interior of the side unit(s) via such door openings. This
embodiment is advantageous with respect to temperature control
inside the nacelle.
[0018] The side unit(s) may be mounted along a side of the main
unit in such a manner that each of the side unit(s) can be moved
directly between the mounted position at the nacelle and a base
level of the wind turbine. The base level is preferably a level
which is arranged at or near the foot of the tower of the wind
turbine, and it may, e.g., be the ground level in the case that the
wind turbine is arranged on land. Alternatively, it may be a sea
level, or it may be a level defined by a transporting vessel, such
as a truck or a barge, adapted to carry a side unit during
transport to the operating site of the wind turbine. In any event
it should be understood that the base level is normally arranged at
a level which is lower than the level of the nacelle. It is noted
that the main unit, the side unit(s) the rotor, the wind turbine
blades and/or any wind turbine component accommodated in the
nacelle may be delivered by means of airborne vessels, such as a
helicopter or an airship.
[0019] Thus, according to this embodiment, movements of a side unit
between the mounted position at the nacelle and a base level
include substantially vertical movements in a downwards direction
from the nacelle towards the base level, as well as substantially
vertical movements in an upwards direction from the base level
towards the nacelle. The side unit(s) can be moved directly between
these two positions, i.e. it/they can be lowered from or hoisted to
the mounted position at the nacelle along a substantially vertical
direction, without having to move the side unit(s) in a sideways or
substantially horizontal direction. This is an advantage because it
allows the side unit(s) to be moved by means of hoisting equipment
arranged in the nacelle, thereby avoiding the need for an external
crane for mounting, repair or replacement of the side unit(s)
and/or of one or more wind turbine components accommodated in the
side unit(s).
[0020] Each side unit accommodates at least one wind turbine
component. In the present context the term `wind turbine component`
should be interpreted to mean components which are required for
operation of the wind turbine, and which are normally arranged in
the nacelle, or which may advantageously be arranged in the
nacelle. Thus, the term `wind turbine component` includes, but is
not limited to, transformer, converter, generator, control units,
hydraulic units, cooling modules, main shaft, various bearings,
gear arrangement, etc. It is an advantage that one or more of the
wind turbine components is/are accommodated in the side unit(s),
since it allows the common interior space defined by the units to
be utilised to the greatest possible extent. Furthermore, it allows
wind turbine components to be hoisted to the nacelle along with the
side unit(s) during erection of the wind turbine, or in the case
that one or more wind turbine components need to be replaced.
Thereby the total weight which needs to be lifted to the top of the
tower during erection of the wind turbine is divided into smaller
portions, and the requirements on the lifting equipment can be
lowered. This reduces the costs involved with erection of,
decommissioning of and/or service on the wind turbine, since
cheaper lifting equipment can be used.
[0021] At least one side unit is capable of carrying the wind
turbine component(s) accommodated therein. Thus, at least one side
unit has a structure which allows it to carry the wind turbine
component(s) without the wind turbine component(s) being supported
by the main unit or the tower, except via the side unit.
[0022] The main unit and at least one of the side unit(s) are
distributed side by side along a transverse direction of the
nacelle, i.e. along a direction which is substantially horizontal
and substantially transverse to a rotational axis of the rotor of
the wind turbine. This is contrary to the situation disclosed in EP
2 063 119, where the nacelle modules are arranged one behind the
other along a direction defined by the rotational axis of the
rotor. It is also contrary to the situation disclosed in DE 10 2007
062 622 A1, where the housing module is arranged below the machine
house. It is an advantage that the main unit and the side unit(s)
are distributed along a transverse direction, because it allows the
side unit(s), and thereby the wind turbine components accommodated
in the side unit(s), to be arranged close to the tower of the wind
turbine. Since the tower carries the nacelle, positioning as much
of the weight as possible as close as possible to the tower reduces
the loads, in particular torque loads, in the nacelle. As a
consequence, the requirements to the strength of the nacelle are
reduced, thereby allowing the weight of the nacelle structure to be
reduced. As a consequence, the loads transferred to the tower are
also reduced, thereby reducing the requirements to the strength of
the tower and allowing a reduction of the weight of the tower
construction. All in all this introduces considerable reductions in
the costs of the wind turbine, since the costs of materials as well
as the costs involved with transport of the parts are reduced. It
is also an advantage that the main unit and the side unit(s) are
distributed along a substantially horizontal direction, because it
allows a better utilisation of the space defined by the main unit
and the side unit(s), since it is possible to obtain one common
floor of the entire interior part of the nacelle, thereby allowing
personnel to move easily inside the nacelle.
[0023] In a preferred embodiment the nacelle comprises two side
units, one mounted on a left side of the main unit and one mounted
on a right side of the main unit, as seen in the direction of the
rotational axis of the rotor of the wind turbine. However, it
should be noted that alternative mutual positions of the units
should also be regarded as falling within the scope of the present
invention.
[0024] At least one side unit may accommodate at least one wind
turbine component arranged in a closed compartment, said closed
compartment being arranged in the side unit. In the present context
the term `closed compartment` should be interpreted to mean an
entity or a housing defining an interior part which is separated
from the remaining part of the interior of the side unit having the
closed compartment arranged therein, e.g. by means of substantially
solid walls. Thereby it is possible to control the environment
inside the closed compartment independently of the environment in
the remaining part of the nacelle, e.g. with respect to
temperature, humidity, pressure, etc. This makes it easy to control
the environment inside the closed compartment to suit the wind
turbine component(s) arranged therein, and by applying two or more
closed compartments, each accommodating one or more wind turbine
components, it is possible to provide different temperature,
humidity and/or pressure to different wind turbine components,
thereby allowing each wind turbine component to be accommodated
under conditions which are optimal for that wind turbine component
without taking other wind turbine components requiring other
environmental settings into consideration.
[0025] Furthermore, arranging one or more wind turbine components
in closed compartment(s) which is/are in turn arranged in the side
unit(s) of the nacelle, allows the wind turbine component(s) to be
mounted in the compartment(s) at the manufacturing site, and to be
transported to the operating site of the wind turbine in the
compartment(s). During the erection of the wind turbine at the
operating site, the compartment(s) can be positioned directly in
the side unit(s), along with the wind turbine component(s)
accommodated therein. This makes it very easy to install the wind
turbine component(s) in the nacelle. The closed compartment(s) may
even be positioned in the side unit(s) at the manufacturing site or
at an assembly site, and transported to the operating site inside
the side unit(s).
[0026] At least one closed compartment may provide a sealing
enclosure for the wind turbine component(s) accommodated therein.
In this case, the closed compartment prevents liquid or moisture
from passing between the interior of the closed compartment and the
remaining part of the interior of the side unit having the closed
compartment arranged therein. Thus, in the case that the closed
compartment accommodates a wind turbine component which must not
get into contact with liquid, e.g. electrical equipment, the closed
and sealed compartment prevents liquid, such as rain water or
liquid originating from other wind turbine components, from
entering the interior part of the closed compartment, thereby
preventing the liquid from reaching the wind turbine component.
Thereby the wind turbine component is protected. Similarly, in the
case that the closed compartment accommodates a wind turbine
component which produces or uses liquid, such as hydraulic oil or
cooling water, such liquid is prevented from leaving the closed and
sealed compartment, and it is thereby prevented that such liquid
reaches other wind turbine components or leaks to the
environment.
[0027] At least one closed compartment may provide electromagnetic
shielding for the wind turbine component(s) arranged in the
compartment. According to this embodiment, the wind turbine
component(s) accommodated in the closed compartment(s) is/are
protected against electromagnetic interference (EMI) and/or damage
caused by lightning strikes. The electromagnetic shielding may,
e.g., be obtained by producing the closed compartment at least
partly from an electrically conducting material, such as a metal.
Thereby the closed compartment functions as a Faraday cage. This
embodiment is particularly useful in the case that sensitive
electrical equipment is accommodated in the closed compartment.
[0028] At least one compartment may be provided with a door
allowing access to the wind turbine component(s) arranged in the
compartment. According to this embodiment, the interior of the
closed compartment may be completely separated from the remaining
part of the interior of the side unit having the compartment
arranged therein during normal operation. However, in the case that
inspection, maintenance and/or replacement of one or more wind
turbine components accommodated in the closed compartment is
required, the door can be opened, thereby providing access to the
wind turbine component(s) for the maintenance personnel.
[0029] The main unit may comprise at least one beam, each beam
being connectable to lifting equipment for mounting and/or
demounting the main unit on/from the wind turbine tower. According
to this embodiment, the main unit may be hoisted to the operating
position on top of the wind turbine tower during erection of the
wind turbine by connecting the beam(s) to lifting equipment and
hoisting the main unit by means of the lifting equipment and via
the beam(s). Similarly, the main unit may be demounted from the
wind turbine tower by means of lifting equipment and via the
beam(s), e.g. in the case that the wind turbine is to be
decommissioned or the main unit needs to be replaced. It is an
advantage of this embodiment that the main unit can be mounted
and/or demounted on/from the wind turbine tower via one or more
parts which form a part of the main unit, i.e. the beam(s), because
the mounting/demounting of the main unit thereby becomes very
easy.
[0030] The beam(s) may form part of a hoisting arrangement for
hoisting and/or lowering wind turbine components and/or side
unit(s) to/from the nacelle. The beam(s) may, e.g., be or form part
of a structural or carrying part of the hoisting arrangement. For
instance, one or more winches or the like may be mounted on the
beam(s), the beam(s) thereby carrying the load of a wind turbine
component or side unit being hoisted to or lowered from the
nacelle. The beam(s) may be arranged on the main unit in such a
manner that it/they extend beyond a side of the main unit towards
the position of a side unit. A hoisting arrangement mounted on such
a beam will thereby be capable of hoisting or lowering a side unit
directly to or from the nacelle as described above.
[0031] Alternatively or additionally, the beam(s) may be adapted to
carry at least one of the wind turbine component(s) accommodated in
one of the side unit(s). According to this embodiment, the wind
turbine component(s) may be mounted on or attached to the beam(s)
once it/they has/have been hoisted to the nacelle. Thereby the
beam(s) carry the wind turbine component(s), and the loads arising
from the wind turbine component(s) are thereby transferred to the
main unit. The requirements to the strength of the side unit(s) may
thereby be lowered, since the loads arising from the heavy wind
turbine components are carried by the main unit.
[0032] As an alternative, the wind turbine component(s), possibly
accommodated in one or more closed compartments as described above,
may be carried by a supporting structure which supports the wind
turbine component(s) from below.
[0033] As mentioned above, at least one of the wind turbine
component(s) accommodated by a side unit may be a transformer. The
side unit accommodating a transformer may, in this case, further
accommodate a converter. The converter may be arranged adjacent to
the transformer and adjacent to a generator of the wind turbine.
This is an advantage, because it reduces the routing of cabling and
provides simple electric transmission pathways, thereby minimising
the current path between the generator and the transformer.
Consequently, the current losses introduced by the cables are also
minimised.
[0034] Furthermore, arranging the converter and the transformer in
the same side unit has the advantage that it allows the transformer
and the converter to be mounted in this side unit and connected to
each other prior to hoisting the side unit to the nacelle, e.g. at
a manufacturing site. This makes it very easy to install these
components at the operating site during erection of the wind
turbine.
[0035] The transformer may be arranged at a position near the
yawing arrangement. Since the transformer is normally a relatively
heavy wind turbine component, it is an advantage to arrange it as
close as possible to the yawing arrangement, and thereby to the
wind turbine tower, since the torque loads on the nacelle and the
tower arising from the weight of the transformer can thereby be
minimised. Other wind turbine components which are less heavy may
then be arranged further away from the wind turbine tower, and the
total loads on the nacelle and the tower can thereby be
minimised.
[0036] At least one of the wind turbine component(s) accommodated
by a side unit may be an on-board crane. According to this
embodiment, an onboard crane is available in the nacelle, e.g. for
moving the wind turbine components accommodated by the main unit
and the side unit(s).
[0037] As an alternative, an onboard crane may be accommodated by
the main unit.
[0038] According to one embodiment, the nacelle may comprise 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. According to this embodiment, the electrical wind
turbine components are arranged in the vicinity of each other,
thereby minimising the routing of cabling as described above.
Furthermore, the electrical wind turbine components are kept
separate from the liquid containing wind turbine components. This
increases the safety of the wind turbine, since the risk of liquids
getting into contact with electrical components is reduced
considerably. Liquid containing wind turbine components may
include, but are not limited to, hydraulic equipment, cooling
modules, fire protection equipment and/or lubricating systems.
Accommodating related liquid containing wind turbine components,
for instance components requiring hydraulic liquid, in the same
side unit furthermore has the advantage that an optimal routing of
the liquid can be obtained, minimising the liquid pathways,
similarly to the advantages obtained by arranging the electrical
wind turbine components in the vicinity of each other.
[0039] At least one side unit may extend substantially along the
entire length of the main unit. In this case the length of the
nacelle, i.e. the distance from the rotor to the rear wall of the
nacelle, is defined by the length of the main unit as well as the
length of said side unit, said lengths being substantially
identical. In this case the nacelle can be easily assembled at the
operating site in a manner defining a common interior space of the
nacelle. Alternatively or additionally, two or more side units may
be arranged side by side along the length of the main unit and
facing the same side of the main unit. Furthermore, it could be
envisaged that two or more side units may be arranged one on top of
the other along a side of the main unit.
[0040] An interface defined by the main unit towards a side unit
may be connectable to a corresponding interface of a crane, upon
removal of the side unit. According to this embodiment, in the case
that a larger crane is required at the wind turbine, a side module
can be lowered by means of hoisting equipment arranged in the
nacelle, and the crane may subsequently be hoisted to the nacelle,
using the same hoisting equipment. Once the crane has been hoisted
to the nacelle it can be mounted on the main unit, using the same
interface which is used for mounting the side unit on the main
unit. This makes it very easy to provide the larger crane, and the
use of large, ground based cranes can be avoided. A larger crane as
described above may, e.g., be required in order to hoist/lower
heavy components, such as gear, drivetrain, generator or rotor
blades, to/from the nacelle. The interface defined by the main unit
may, e.g., include one or more flanges and/or one or more bolt
openings allowing the side unit or the crane to be mounted on the
main unit.
[0041] The side unit(s) may be adapted to accommodate the wind
turbine component(s) during transport from a manufacturing location
to a wind turbine site. According to this embodiment, the wind
turbine components may be mounted in the side unit(s) at the
manufacturing location, and the side unit(s) may then be
transported to the wind turbine site or operating site along with
the wind turbine components which have been mounted therein. This
facilitates the process of mounting the wind turbine components
considerably, since it is much easier to mount the wind turbine
components while the side unit(s) is/are located on the ground and
indoors than it is to mount them when the side unit(s) is/are
located at the top of the wind turbine tower at the operating site
of the wind turbine. Furthermore, a side unit and all the wind
turbine components accommodated therein can be hoisted to the
nacelle in one go, thereby reducing the amount of time required for
erecting the wind turbine at the operating site.
[0042] According to one embodiment, two side units, each
accommodating one or more wind turbine components, may be joined
together at the manufacturing location in such a manner that a
substantially closed unit is formed. This closed unit may
subsequently be transported to the operating site of the wind
turbine, where the side units are once again separated before they
are hoisted to the nacelle and mounted on the main unit.
[0043] Alternatively or additionally, the side unit(s) may comprise
connecting means allowing (a) transportation cover(s) to be
attached to the side unit(s) during transport of the side unit(s),
e.g. from a manufacturing location to a wind turbine site.
According to this embodiment, the transportation cover may be
attached to a side unit at the manufacturing site, and the side
unit, with the transportation cover attached thereto, can be
transported to the operating site of the wind turbine. The
transportation cover protects the side unit as well as the wind
turbine component(s) accommodated therein during the transport.
When the side unit arrives at the operating site of the wind
turbine, the transportation cover can be removed before the side
unit is mounted on the main unit of the nacelle.
[0044] The transportation cover may substantially enclose the
entire side unit. As an alternative, the transportation cover may
only partly enclose the side unit. This may, e.g., be the case if
the side unit is provided with a cover or a cover part which forms
part of a nacelle cover during operation of the wind turbine. In
this case the transportation cover may only cover the parts of the
side unit which are not already covered by the cover or cover part,
and the side unit may be entirely covered by the cover or cover
part and the transportation cover in combination during
transportation. The parts of the side unit covered by the
transportation cover may, e.g., include an interface of the side
unit towards the main unit.
[0045] The nacelle may further comprise a cover covering at least
part of the main unit and at least part of at least one of the side
unit(s). According to this embodiment, a common cover is provided
to at least partly cover the main unit as well as at least one of
the side unit(s). Thereby the nacelle, with the main unit and the
side unit(s), appears as a single unit of the wind turbine, even
though the main unit and the side unit(s) are structurally separate
parts.
[0046] As an alternative, the nacelle may further comprise 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. According to this
embodiment, the main unit and the side unit(s) are provided with
separate covers. The main cover and the side cover(s) may be joined
together during erection of the wind turbine or assembly of the
nacelle, in such a manner that they form a boundary between the
interior of the nacelle and the exterior. As described above, the
separate covers may be useful for at least partly covering the main
unit and the side unit(s) during transport from the manufacturing
site to the operating site of the wind turbine.
[0047] At least one cover may be provided with at least one opening
allowing passage of wind turbine components. The opening may
advantageously be provided with a closing element, e.g. in the form
of a door, a hatch or the like, in which case the nacelle may be
completely enclosed during normal operation, and access can be
gained to the interior of the nacelle by opening or removing the
closing element, when this is required.
[0048] According to one embodiment, at least one side unit may be
mounted along a first side of the main unit and a cooling device
having a cooling area may extend from a second side of the main
unit, the second side being arranged opposite to the first side.
According to this embodiment, a side unit and a cooling device are
mounted on opposing sides of the main unit. The cooling device
provides cooling for one or more heat producing components of the
nacelle, such as a generator, a transformer, a gear box, a
frequency converter, etc.
[0049] The nacelle may comprise 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.
[0050] The present invention further relates to a wind turbine
comprising a nacelle according to the first aspect of the
invention.
[0051] According to a second aspect the invention provides a method
for erecting a wind turbine, said wind turbine comprising a nacelle
according to the first aspect of the invention, the method
comprising the steps of: [0052] erecting a wind turbine tower,
[0053] mounting a main unit on the wind turbine tower, via a yawing
arrangement, [0054] 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 [0055] connecting the side
unit to the main unit in such a manner that a common interior
nacelle space is defined by the main unit and the side unit(s).
[0056] It should be noted that a person skilled in the art would
readily recognise that any feature described in combination with
the first aspect of the invention could also be combined with the
second aspect of the invention, and vice versa.
[0057] The method may further comprise the step of transporting 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 side unit(s).
[0058] The step of connecting the side unit to the main unit may be
performed in such a manner that the main unit and the 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. This has already been described above with
reference to the first aspect of the invention, and the remarks set
forth above are equally applicable here.
[0059] As an alternative, a wind turbine comprising a nacelle
according to the first aspect of the invention may be erected in
the following manner. The main unit and the side unit(s) are
manufactured separately and transported to an assembly location,
e.g. at a port or harbour. The main unit and the side unit(s) are
then assembled at the assembly location to form the nacelle, and
the assembled nacelle is transported to the operating site of the
wind turbine where it is mounted on a tower construction. This
approach may be desirable in the case that the operating site is an
offshore site, since the assembled nacelle can in this case be
transported by means of a ship or a barge, where it is possible to
transport larger items than it is using trucks. Furthermore, it is
desirable that the assembly of the nacelle can take place on ground
rather than at the offshore site.
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 minimised 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.
* * * * *