Nacelle for a wind turbine

Abstract

A wind turbine nacelle configured for mounting on a wind turbine tower and for supporting a rotor-supporting assembly, the nacelle comprising a main unit, and at least two auxiliary units. To increase flexibility and improve assembly and maintenance procedures of the wind turbine, the auxiliary unit comprises at least two auxiliary units each accommodating at least one wind turbine component, e.g. a converter or a transformer. The auxiliary units are attached individually to the same wall of the main unit, e.g. to a side wall or a rear wall.

Claims

1. A wind turbine nacelle configured for mounting on a wind turbine tower and housing a rotor-supporting assembly defining a rotational axis, the nacelle comprising: a main unit arranged to be connected to the wind turbine tower and housing the rotor-supporting assembly, the main unit comprising: a first side wall and a second side wall on opposite sides of the rotational axis, and a rear wall extending transverse to the rotational axis between the side walls, and a plurality of auxiliary units, at least some of the plurality of auxiliary units being arranged along the rear wall and at least one of the first side wall and the second side wall of the main unit, wherein: the main unit and a first of the plurality of auxiliary units are assembled at a first interface, the main unit and a second of the plurality of auxiliary units are assembled at a second interface, and both the first and the second interfaces are in a first wall being one of the first side wall, the second side wall, or the rear wall.

2. The nacelle according to claim 1, wherein: the main unit and a third of the plurality of auxiliary units are assembled at a third interface, the main unit and a fourth of the plurality of auxiliary units are assembled at a fourth interface, and both the third and the fourth interfaces are in a second wall being one of the first side wall, the second side wall, or the rear wall.

3. The nacelle according to claim 2, wherein: the main unit and a fifth of the plurality of auxiliary units are assembled at a fifth interface, the main unit and a sixth of the plurality of auxiliary units are assembled at a sixth interface, and both the fifth and the sixth interfaces are in a third wall being one of the first side wall, the second side wall, or the rear wall.

4. The nacelle according to claim 3, wherein the first wall is the first side wall, the second wall is the second side wall, and the third wall is the rear wall.

5. The nacelle according to claim 2, wherein: the first auxiliary unit and a seventh of the plurality of auxiliary units are assembled at a seventh interface, the second auxiliary unit and an eighth of the plurality of auxiliary units are assembled at an eighth interface, the third auxiliary unit and the seventh auxiliary units are assembled at a ninth interface, and the fourth auxiliary unit and the eighth auxiliary units are assembled at a tenth interface, and the first wall being the first side wall, the second wall being the second side wall, and both the seventh auxiliary unit and the eighth auxiliary unit extending along the rear wall.

6. The nacelle according to claim 5, wherein the main unit and the seventh auxiliary unit are assembled at an eleventh interface, and the main unit and the eighth auxiliary unit are assembled at a twelfth interface.

7. The nacelle according to claim 1, wherein at least one of the first, third, fifth, and seventh auxiliary units forms an upper unit and at least one of the second, fourth, sixth, and eighth auxiliary units forms a lower unit arranged below the upper unit and aligned therewith in a vertical row.

8. The nacelle according to claim 7, wherein the lower unit and the upper unit have substantially the same shapes and/or sizes when seen in a horizontal cross section.

9. The nacelle according to claim 7, wherein the upper unit and the lower unit have a total height which is between 80 and 120 percent of a height of the main unit.

10. The nacelle according to claim 1, wherein a gap is defined between at least one of: the main unit and at least one of the plurality of auxiliary units, and two adjacent auxiliary units of the plurality of auxiliary units, said gap allowing air to respectively pass between the at least one of the main and auxiliary units and the two adjacent auxiliary units.

11. The nacelle according to claim 10, wherein the gap is defined both between: the main unit and the at least one of the plurality of auxiliary units, and the two adjacent auxiliary units of the plurality of auxiliary units.

12. The nacelle according to claim 11, wherein the gap between the two adjacent auxiliary units and the gap between the at least one of the plurality of auxiliary unit and the main unit are interconnected.

13. The nacelle according to claim 1, comprising an entrance from the main unit to at least one of the plurality of auxiliary units.

14. The nacelle according to claim 1, comprising an entrance from one of the plurality of auxiliary units to another of the plurality of auxiliary units.

15. The nacelle according to claim 13, comprising a gasket sealingly engaging at least one of: two adjacent auxiliary units of the plurality of auxiliary units, and at least one of the plurality of auxiliary units and the main unit to form a sealing engagement between the engaged parts.

16. The nacelle according to claim 1, wherein each of the plurality of auxiliary units forms a space which can be separated air-tightly from a space in the main unit.

17. The nacelle according to claim 1, wherein at least one of the plurality of auxiliary units has the size or shape of a shipping container of 10, 20, 40 or 45 foot size.

18. A wind turbine comprising a nacelle according to claim 1.

19. A method of making a nacelle for a wind turbine, the method comprising: receiving a plurality of wind turbine components being encapsulated in a plurality of auxiliary units, and attaching the plurality of auxiliary units with the encapsulated components to a main unit of the nacelle, wherein at least some of the plurality of auxiliary units are arranged along a rear wall and at least one of a first side wall and a second side wall of the main unit.

20. The method according to claim 19, wherein the main unit is attached to a wind turbine tower, and wherein the plurality of wind turbine components remain encapsulated in the plurality of auxiliary units until the main unit is attached to the tower.

21. The method according to claim 19, wherein the plurality of auxiliary units are arranged to hermetically isolate one of the plurality of wind turbine components from another one of the plurality of wind turbine components.

22. The method according to claim 19, wherein one of the plurality of auxiliary units is released from another of the plurality of auxiliary units and from the main unit in response to an incident.

Description

LIST OF DRAWINGS

(1) In the following, embodiments of the disclosure will be described in further details with reference to the drawing in which:

(2) FIGS. 1a and 1b illustrate wind turbines;

(3) FIG. 2 illustrates the nacelle of the wind turbine;

(4) FIG. 3 illustrates a perspective view of the nacelle 2 of FIG. 2;

(5) FIG. 4 illustrates the nacelle from FIG. 3 but seen from above;

(6) FIG. 5 illustrates an embodiment where the left and right side auxiliary units contain identical components;

(7) FIG. 6 illustrates an embodiment where two auxiliary units 61, 62 are located one above the other;

(8) FIG. 7 illustrates schematically details of the interface between the main unit and one of the auxiliary units;

(9) FIGS. 8a and 8b illustrate the main unit and auxiliary unit in an embodiment where the auxiliary units are arranged in a vertical row;

(10) FIGS. 9a and 9b illustrate details of the main and auxiliary units;

(11) FIGS. 10-11 illustrate details of different layouts with a gap between the units;

(12) FIGS. 12-15 illustrate 4 different embodiments of interfaces between the main unit and the auxiliary unit.

(13) FIGS. 16-18 illustrate an embodiment where the main unit and auxiliary units are assembled by a hinge structure;

(14) FIGS. 19a, 19b, 19c and, 20 illustrate further details of a hook for attaching the auxiliary unit to the main unit;

(15) FIG. 21 illustrates the hook in an open position where the auxiliary unit is free to be lowered to the ground;

(16) FIG. 22 illustrates a cross section with two bolt holes for attachment of the auxiliary unit on the main unit;

(17) FIGS. 23, 24, 25 illustrate an embodiment where the hook is slidingly suspended; and

(18) FIGS. 26-28 illustrate embodiments of cranes on the main unit for hoisting the auxiliary units.

DESCRIPTION OF EMBODIMENTS

(19) The detailed description and specific examples, while indicating embodiments, are given by way of illustration only, since various changes and modifications within the spirit and scope of this disclosure will become apparent to those skilled in the art from this detailed description.

(20) FIGS. 1a and 1b illustrate wind turbines 1 with a nacelle 2 mounted on a tower 3. A hub 4 carrying three rotor blades 5 forms a rotor and is carried by a rotor-supporting assembly in the nacelle 2. Typically, the rotor-supporting assembly comprises a rotor shaft connecting a gear arrangement and a generator to the hub. A gear is, however, not always required since the generator could be directly driven by the shaft. FIG. 1b illustrates a direct drive wind turbine with the generator 6 located outside the nacelle.

(21) FIG. 2 illustrates that the nacelle comprises a main unit 20 and two auxiliary units 21, 22. A cooling area 23 is arranged on top of the nacelle. The cooling area is formed by a heat exchanger which may form part of the main unit, and/or any of the auxiliary units. The main unit 20 is mounted on the 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. Two separate auxiliary units 24, 25 are both joined to the main unit as two separate auxiliary units. Additionally, the auxiliary units could be joined along the additional interface 26 to form the auxiliary unit as one assembled entity.

(22) FIG. 3 illustrates 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 20 accommodates a main bearing unit 31, a gear arrangement 32 and a generator 33, arranged sequentially behind the hub 4, along a direction defined by the rotational axis of the hub 4.

(23) The auxiliary unit 21 accommodates a transformer unit 34 in a rearward auxiliary unit 36, and a converter unit 35 in a forward auxiliary unit 37. The division between the auxiliary units is illustrated by the transverse bulkhead 38. The rearward and forward units are separate units which can be separated from each other and which can be separated individually from the main unit.

(24) Each auxiliary unit 21, 22 is mounted along a side of the main unit 20 via a first interface. In the disclosed embodiment, they are mounted in such a manner that one auxiliary unit 21 is mounted along a right side of the main unit 20 and the other auxiliary unit 22 is mounted along a left side of the main unit 20, 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 20. The auxiliary units are joined along an additional interface. As illustrated by the bulkhead 38, the second interface may extend perpendicularly to the first interface.

(25) The main unit and the auxiliary units comprise cooperating openings 39 allowing personnel to enter from a main space in the main unit into an auxiliary space in the auxiliary unit. In a similar manner, the auxiliary units may comprise cooperating openings allowing personnel to enter from one auxiliary unit into an adjacent auxiliary unit.

(26) FIG. 4 illustrates the nacelle from FIG. 3 but seen from above. Both of the auxiliary units 42, 43 of the auxiliary unit 22 have a wall part against the wall of the main unit. The bulkhead 44 is placed between the converter unit 35 and the transformer unit 34 and indicates the second interface and split between two auxiliary units.

(27) FIG. 5 illustrates an embodiment where the left and right side auxiliary units contain at least one identical component establishing a weight balance and a double function. The double function means that the wind turbine comprises two identically functioning components, one contained in each of the auxiliary units. In case of failure, the wind turbine may continue operational on half power while the operative component in one of the auxiliary units is replaced. In FIG. 5 it is further illustrated that two auxiliary units are separated by the bulkheads 51. Accordingly, each of the double functioning components, i.e. the transformer or the converter, may be replaced individually in each of the two auxiliary units.

(28) FIG. 6 illustrates an embodiment where two auxiliary units 61, 62 are located one above the other. The auxiliary unit 61 is an upper auxiliary unit constituted by a 40 foot container, and the auxiliary unit 62 is a lower auxiliary unit constituted by a 20 foot container.

(29) FIG. 7 illustrates details of an embodiment of one of the interfaces. The interface joins the main unit 20 with the auxiliary unit 71 in a releasable manner and allows one auxiliary unit of an auxiliary unit to be replaced e.g. during maintenance. The interface is constituted by an inward track or track 73 in one of the sub-units 72. The track 73 is illustrated with a dotted line and defines a recess into the outer surface 75. The track has a C-shaped profile in a horizontal cross section, i.e. when seen from above. the track is configured to receive the projection 74 provided on the auxiliary unit, and particularly it can receive the projection 74 in a very simple procedure where the auxiliary unit 71 is lowered down along the outer surface 75 of the main unit 20. This is illustrated by the arrow 76. This very simple procedure allows easy replacement of an auxiliary unit without detachment of the other auxiliary unit(s) from the main unit.

(30) FIGS. 8a and 8b illustrate an embodiment wherein the nacelle comprises a main unit 20 and three sets each constituted by two auxiliary units 61, 62. In the illustrated embodiment, each auxiliary unit is attached directly to the main unit, but they could also be attached to the other auxiliary unit. The upper auxiliary unit 61 and the lower auxiliary unit 62 are identical units aligned in a vertical row. Since the upper unit and the lower unit have identical shapes and sizes when seen in a horizontal cross section, the upper unit forms a roof over the lower unit.

(31) In this embodiment, the auxiliary unit, i.e. the stack of two auxiliary units have nearly the height of the main unit, and both auxiliary units are suspended on the same side wall of the main unit. The auxiliary units are provided on the rear wall of the main unit, and on opposite side walls of the main unit 20.

(32) FIG. 8b illustrates the same nacelle but with sides of the auxiliary units removed to illustrate that the upper unit units 61 like the lower units 62, i.e. they contain the same components, in this case a transformer and converter. The transformer or converter in the upper unit could be identical to the transformer or converter in the lower unit, or they could be different e.g. with respect power rating.

(33) FIGS. 9a and 9b illustrate two different details of the main and auxiliary units. In FIG. 9a, the upper and lower auxiliary units 61, 62 are directly against each other. In this embodiment, load from the upper unit 61 could be transferred to the lower unit 62, and the auxiliary units could be joined to each other by further interfaces.

(34) In FIG. 9b, the upper and lower auxiliary units 61, 62 are arranged with a distance from each other. In this embodiment, load from the upper unit 61 is transferred exclusively to the main unit 20, and the auxiliary units are only joined to the main unit 20.

(35) FIGS. 10-11 illustrate different layouts provided by the first and second interfaces respectively.

(36) In FIG. 10, the first interface provides a gap between the main unit and the auxiliary unit. This gap allows air to pass between the main and auxiliary units and thereby supports efficient cooling by convection. Additionally, the gap increases safety e.g. by preventing fire to spread.

(37) In FIG. 11, a gap is defined between the auxiliary unit. Again, the gap allows air to pass between the auxiliary units and thereby supports efficient cooling by convection and increases safety.

(38) FIGS. 12-15 illustrate four different embodiments of a unit fixation structure forming part of one of the interfaces between an auxiliary unit and the main unit or between two auxiliary units. In each of these four illustrations, the auxiliary unit, 121 and the main unit 122 are connected by cooperating structures described below. The same structure may apply for joining two auxiliary units.

(39) In FIG. 12, the cooperating structures are constituted by brackets 123 by which the units are joined by bolts.

(40) In FIG. 13, the cooperating structures are constituted by a lower bracket 123 similar to the one used in FIG. 12. At the upper edge, the units are assembled by a hook 131 pivotally joined to the first auxiliary unit at the hinge point 132. The hook can rotate as indicated by the arrow 133 and engages the edge-bracket 134 of the unit when in the illustrated position. When the lower bracket 123 is removed, and the hook 131 is rotated into the unit, the second auxiliary unit can be lowered to the ground.

(41) The embodiment in FIG. 14 is comparable to the embodiment in FIG. 13, but where the lower bracket is replaced with an upper bracket 141, and the hook is placed at a lower edge.

(42) In FIG. 15, a lower and an upper bracket is used for bolting the auxiliary unit to the main unit, and a slidable support 151 supports the lower surface of the second auxiliary unit while the bolts are attached. If it is desired to lower the second unit to the ground, e.g. for replacement or maintenance of the operative component, the slidable support can be slided to the left and the auxiliary unit can be lowered, e.g. by use of a crane build into the first auxiliary unit. In any of the embodiments shown in FIGS. 12-15, the brackets or hooks direct the load from the auxiliary unit into a rigid part of the main unit, e.g. into load carrying column e.g. a corner column of the main unit. Various structural features may connect the brackets or hooks which carry the auxiliary unit directly to the main frame in the main unit to thereby establish a load path into the tower.

(43) FIGS. 16-18 illustrate an embodiment where the auxiliary unit and the main unit are assembled by a hinge structure comprising hinge elements 163, 164, 165 with a hole for receiving a hinge pin 166 extending through the hinge elements. FIG. 16 further shows that the interface forms a gap 167 allowing air to pass e.g. from beneath the nacelle to above the nacelle, through the gap. The gab is held open at the bottom by the distance element 168, which could be constituted by a number of pins or an open structure allowing air to pass between the units.

(44) Such a gap may increase thermal convection and thus cooling of the space inside the units. The gap is not limited to the embodiment with the hinge structure but could be combined with any other assembly method.

(45) FIGS. 17 and 18 illustrate the hinge elements 163, 164, 165 and the hinge pin 166. In FIG. 17, the hinge elements are positioned correctly relative to the each other such that the hinge pin can be slided into the hinge elements. In FIG. 18, the hinge pin is inserted through the holes of the hinge elements.

(46) FIGS. 19a, 19b, and 19c illustrate further details of a hook for attaching the one unit 191 to another unit 192, e.g. an auxiliary unit to the main unit or an auxiliary unit to another auxiliary unitherein just referred to as first and second units. The hook 193 is suspended rotationally at the hinge 194 in the first unit and catches a recess or edge 195 in the second unit.

(47) The hook could also be attached in the second unit and catch a recess or edge in the first unit, in which case it may be attached reversely, i.e. as illustrated in FIG. 20. The hook may be positioned by use of an actuator.

(48) FIG. 21 illustrates the hook in an open position where the second unit is free to be lowered to the ground.

(49) FIG. 22 illustrates a cross section where two bolt holes 221 can be seen. The bolt holes facilitate attachment of the second unit on the first unit by use of bolts for solid fixation. In this embodiment, the hook is mainly for positioning the second unit in the correct height relative to the first unit, and the bolts are for joining the units.

(50) In FIGS. 19, 21 and 22, the hook is preferably supported by a rigid frame structure, e.g. via column or support posts arranged along an inner surface of the unit which holds the hook. In FIG. 19, the column 197 extends along an inner surface of the unit and supports the hook on the main frame in the bottom part of the unit.

(51) The hook could be moved between the open position (FIG. 21) and the closed position (FIG. 19, 20, 22) by power driven means, e.g. including a hydraulically driven actuator.

(52) FIGS. 23, 24, 25 illustrate an embodiment where the hook is not rotationally suspended but slidingly suspended. The function is like the embodiment of FIGS. 19-22. In FIGS. 23 and 24, a cross sectional view illustrates a bolt hole 231 which can be used for solid, bolted joining of the units.

(53) In FIG. 25a, the hook 251 is slided to the left thereby disengaging the edge of the unit and allowing the unit to be lowered to the ground. In FIG. 25b, the hook 251 is slided to the right, thereby engaging the edge of the auxiliary unit and holding the two units fixed to each other. The hook may be slided by power driven means, e.g. by a hydraulic actuator.

(54) In the description above, FIGS. 19-25 are explained as parts of the unit fixation structure for joining the units.

(55) FIG. 26 illustrates hoisting a unit up or down during maintenance or replacement. The unit is hoisted by use of a crane 261 forming part of the main unit or forming part of one of the auxiliary units. Movement is essentially only in the vertical plane, illustrated by the arrow 263, and the attachment of the auxiliary unit or one of the auxiliary units may be facilitated by a unit fixation structure as described previously, including movable fixation features such as hinged or slidable hooks etc.

(56) FIG. 27 illustrates the internal crane 261 in an enlarged view. The crane is attached to a roof part of the main unit or one of the auxiliary units and by its location, it can hoist other units in a vertical direction to a position where said unit fixation structures can form engagement between the units. This procedure may not require movement in other directions than the vertical direction and therefore facilitates a simple assembly procedure with reduced need for external crane assistance. For adjustment in a horizontal plane, the crane 261 may have the option of moving horizontally, e.g. as illustrated by the arrow 262.

(57) FIG. 28 illustrates schematically, another crane structure with a double cantilever beam 281 on the roof of the main unit 282 or on the roof of one of the auxiliary units. The cantilever beam 281 can extend sideways in telescopic section 283. The cantilever beam facilitates lifting and connection of another unit 284. Even though the unit fixation structures disclosed herein, including pivotable or slidable hooks, generally facilitate attachment of the auxiliary unit or auxiliary unit by hoisting only in the vertical direction, the in and out movement facilitates fine adjustment of a horizontal distance between the main unit and the auxiliary unit.

DEFINITIONS

(58) Herein, the term nacelle means the generally accepted term describing the machine house for a wind turbine, i.e. that part which carries the rotor and drivetrain, and which is carried by the wind turbine tower.

(59) The terms main unit and auxiliary unit herein refers to units which can be transported separately, and which can be assembled with one or more other units to form the nacelle.

(60) Herein, the term rotor-supporting assembly refers to those parts of the nacelle which carries the rotor, typically a drivetrain, a main bearing and a main frame. The drivetrain may include different components depending on the type of wind turbine, e.g. a rotor shaft, the generator, and optionally a gearbox between the rotor shaft and the generator.