The present invention relates to the field of wind turbines, and in particular, to the installation of blades for wind turbines.

Wind turbines today typically have a rotatable hub with blades connected to the hub at a top end of a tower. In some projects, it can be convenient to transport some of these components in a disassembled condition to the intended site for installation of the wind turbine.

At the site, the blades for example may need to be connected to the hub (often termed a“nacelle”). The blades may need to be connected so as to be placed at the correct pitch to allow the blades and hub to be turned by the wind. This can require end connectors of the blades to be aligned accurately against correspond- ing connectors of the rotatable hub.

Such positioning of a blade relative to the hub can be challenging, not least as each blade is generally a large, heavy, and/or cumbersome object. In prior art solutions, cranes have been employed at the site to lift the blade into the correct position for allowing connection to the hub. Attention in the wind turbine industry has also recently turned toward offshore wind turbines. At offshore sites, the pro vision of cranes to assist in installation of blades may typically require dedicated crane barges and/or specialist vessels to be commissioned which can be incon venient and costly. In addition, waves, currents, and/or wind in the offshore envi- ronment can exacerbate difficulties in handling and positioning blades using cranes.

It can be appreciated that while it may be convenient to transport components in disassembled condition, the practicality and/or efficiency of assembling the com ponents when at the site can be a competing consideration. Prior solutions for transporting components and installing wind turbines can lack practicality and effi ciency. An aim of the invention is to obviate or at least mitigate one or more drawbacks of prior art.

According to a first aspect of the invention, there is provided a tool for positioning a blade for a wind turbine for facilitating installation of the blade, the wind turbine including a tower and a rotatable hub on an upper end of the tower, the tool con figured to be mounted on a side of the tower for supporting the blade on the tower, the tool comprising at least one part and at least one other part, wherein the one part is arranged to be angularly movable relative to the other part for tilting the blade with respect to the tower, to position the blade.

The one part may be further arranged to be both angularly movable and linearly translatable relative to the other part. The linear translatability may comprise line ar translation in a first direction for moving the blade along the tower. The linear translatability may comprise linear translation in a second direction. The second direction may be different, e.g. orthogonal to the first direction.

The one part may comprise a mount for the blade. The mount may comprise a gripping device. The mount may be arranged to bear against the blade. The mount may comprise a gripping device for gripping the blade for attaching the blade to the tool.

The other part may comprise a support which may be configured to be fixedly connected to the tower.

The tool may further comprise a positioner which may include the one part. The positioner may include the other part. Alternatively, the positioner may not include the other part. The positioner may be movable e.g. translatable with respect to the other part.

The tool may further comprise first, second, third, fourth parts, which may be mov- ably coupled to one another. In such embodiments, the one part may be the

P28549PC00 Description and claims fourth part, the other part may be the first part, and the second and third parts may be parts for movably coupling between the first and second parts.

In embodiments where the tool comprises first, second, third, and fourth parts, ei- ther or both of the second and third parts may be movable relative to the fourth part, e.g., for moving the blade radially with respect to the tower and/or tilting the blade for modifying an angle between a longitudinal axis of the blade and a longi tudinal axis of the tower. The fourth part may be coupled to the third part by a piv ot and may be rotatable relative to the third part about the pivot for changing an angle between them. Either or both of the third and fourth parts may be linearly movable relative to either or both of the first and second parts for moving the blade radially with respect to the tower. The second part may be linearly movable rela tive to the first part for translating the second, third and fourth parts along the tow er.

The tool may further comprise at least one actuator for driving the movement be tween the one part and the other part. The actuator may comprise at least one linear extender. The support may comprise a locking device for connecting and locking the other part of the tool fixedly to the tower. The locking device may be releasable from the tower by remote operation, e.g. after use of the tool.

The tool may further comprise a winch which may comprise a flexible elongate member having an end configured to be attached to the tower or other part of the wind turbine. The elongate flexible member, e.g. a winch wire, may be spoolable from a drum of the winch for lowering the tool from the tower after use.

According to a second aspect of the invention, there is provided an installation as sembly for a wind turbine comprising: a tower; a rotatable hub on an upper end of the tower; at least one blade for the wind turbine; and at least one tool mounted on a side of the tower, the tool supporting the blade on the tower and comprising at

P28549PC00 Description and claims least one part which is angularly movable with respect to at least one other part to tilt the blade relative to the tower to position the blade.

According to a third aspect of the invention, there is provided a method of installing at least one blade for a wind turbine, the method comprising the steps of: providing a tool comprising at least one part which is angularly movable relative to at least one other part, the tool mounted on a side of an upright tower for the wind turbine, a rotatable hub provided on an upper end of the tower, the blade attached to the tool and supported on the tower via the tool; and operating at least one actuator to produce relative angular movement between the one part and the other part of the tool to position the blade in an installation position.

In another aspect, there is provided a tool for positioning a blade for a wind turbine for facilitating installation of the blade, the wind turbine including a tower and a rotatable hub on an upper end of the tower, the tool configured to be mounted on a side of the tower for supporting the blade on the tower, the tool comprising at least one part movable relative to at least one other part to position the blade with re spect to the tower. In another aspect, there is provided a tool for positioning a blade for a wind turbine for facilitating installation of the blade, the wind turbine including a tower and a rotatable hub on an upper end of the tower, the tool configured to be mounted on a side of the tower for supporting the blade on the tower, the tool comprising at least one part which is movably coupled to at least one other part for tilting the blade with respect to the tower to position the blade. Parts may be movably coupled for producing or obtaining relative angular movement therebetween, e.g. angular movement of the one part relative to the other part.

Any of the various aspects of the invention may include further features as de scribed in relation to any other aspect, wherever described herein. Features de scribed in one embodiment may be combined in other embodiments. For exam ple, a selected feature from a first embodiment that is compatible with the arrangement in a second embodiment may be employed, e.g. as an additional,

P28549PC00 Description and claims alternative or optional feature, e.g. inserted or exchanged for a similar or like fea ture, in the second embodiment to perform (in the second embodiment) in the same or corresponding manner as it does in the first embodiment. Various advantages of the embodiments of the invention and its features are de scribed and will be apparent from the specification throughout.

There will now be described, by way of example only, embodiments of the inven tion with reference to the accompanying drawings, in which:

Figure 1 is side-view representation of a tool for installing a blade for a wind turbine according to an embodiment of the invention;

Figure 2 is rear-view representation of the tool of Figure 1 ;

Figure 3 is a side-view representation of a tower for the wind turbine with the tool of Figure 1 arranged on the tower;

Figure 4 is a cross-sectional representation along the line X-X of Figure 3; Figure 5 is a side-view representation of the tower of Figure 3, where the tool is activated to position the blade for installation;

Figure 6 is a perspective view of the tool of Figure 1 in use for positioning the blade with respect to a tower for the wind turbine according to anoth er embodiment, where the blade is shown in a first position; and

Figure 7 is a perspective view of the tool in use in the embodiment of Figure 6, where the blade is shown in a second position. Referring first to Figures 1 and 2, there is generally depicted a tool 1 for position ing a wind turbine blade.

The tool 1 is attachable to an outside of a wind turbine tower, and operates to modify its extent or configuration between the wind turbine tower and the blade, so that the blade can be moved with respect to the tower and positioned appropriately to allow connection of the blade to a hub supported at an upper end of the tower.

P28549PC00 Description and claims The tool has a structure including a number of coupled parts which are movable relative to one another. The parts are coupled, as will be described further in the following, so as to produce movement of at least one of the parts with respect to the tower, when mounted thereto, in directions vertically along the tower, laterally away from the side of the tower, and rotationally about a horizontal axis.

This functionality of movement may be embodied in various ways. In the present example, such parts include a support 100 and a positioner 200. The support 100 (“first part”) is arranged to be fixed rigidly to the side of the tower. The support 100 includes a frame 12 with connectors 1 1 a, 1 1 b that fix the frame 12 and tool in place on the side of the tower in a desired location along the tower. (When on the tower and the tower is upright, the tool is arranged as shown in the orientation of the figure.)

The positioner 200 is movably coupled to the support 100. The positioner 200 as a whole is movable with respect to the support 100, whilst still supported there upon. The positioner 200 includes individual parts which are movably intercon nected, the parts including a main body 20 (“second part”), an extender member 30 (“third part”), and a mount 40 (“fourth part”). The wind turbine blade is attached to the mount 40, by suitable means such as described further below. These inter connected parts then combine under operation for obtaining a position and orien tation of the mount 40 to facilitate bringing the attached wind turbine blade into the desired alignment for connection to the hub.

The main body 20 has a frame 22 including a platform section 23, slider section 24, and a stay 25 connected in a triangular formation. As can be appreciated from Figure 1 , the slider section 24 comprises a vertical column, and the platform 23 comprises a beam extending from an upper end of the column of the slider 24 or- thogonally away from the column toward a far end. The stay 25 connects between the column and the beam of the respective slider section 24 and platform 23, by reaching away from the lower end of the slider section at an angle to the column to

P28549PC00 Description and claims join the beam at its far end. Thus, the platform 23 projects laterally away from the support 100 in Figures 1 and 2.

The slider section 24 engages with the frame of the support 100. Furthermore, the slider section 24 is slidably received within a section of the frame 12 of the support 100, so that the section 24 is movable with respect to the frame 12 as indicated by arrow A. More specifically, the slider section 24 comprises a rod that extends, from a lower end to an upper end, through a tubular section of the frame 22 of the support 100. In this way, the main body 20 is securely coupled to the support 100.

The frame of the main body 20 provides therefore a solid and robust structure which can transfer and distribute the loads from the wind turbine blade onto the tower. An actuator 28 is provided for driving movement of the main body 20 with respect to the support 100. The actuator 28 is a linear actuator which can extend or re tract in the direction of movement indicated by arrow A. One part of the actuator 28 is fixed to the frame 12 of the support 100, and another part of the actuator 28 is fixed to the frame 22 of the main body 20. Thus, by operating the actuator 28 the two parts of the actuator 28 are moved relative to one another, producing rela tive movement between the support 100 and the main body 20 whereby the slider section 24 slidably moves upward along the inside of the frame 12. In this exam ple, by shortening the length of the actuator 28, the main body 20 is driven upward with respect to the support 100. The amount of upward movement is determined by the amount of attainable shortening of the actuator.

Turning now to consider the extender body 30, it can also be seen in Figures 1 and 2 that the extender body is movably coupled to the main body 20. The ex tender body 30 is movable relative to the main body 20 as indicated by the arrow B. The extender body 30 comprises a slider section 34 which is arranged to slide and extend out from the frame 20. By doing so, the spacing of the mount 40 away from the support 100 can be adjusted. An actuator 38 is provided for moving the extender body 30 with respect to the main body 20. The actuator 38 is a linear

P28549PC00 Description and claims actuator with direction of extension and/or retraction in direction B. The extender body 30 is movable linearly from the main body 20 using the actuator 38. One part of the actuator 38 engages the frame 22 and another part of the actuator 38 engages the slider section 34. By lengthening or shortening the actuator 38, the extender body 30 is moved laterally with respect to the main body 20. The amount of lateral movement is determined by the amount of attainable lateral movement of the actuator.

The mount 40 is movably coupled to the extender body 30. More specifically, the mount 40 is coupled to the extender body 30 via a pivot 41 , and can be moved rotationally about a horizontal axis P at the pivot 41 so as to change the angle b. The rotational movement of the mount 40 relative to the extender 30 is facilitated by the actuator 48 which is a linear actuator with direction indicated by arrow C having a part which is connected to the stay 25 and a part connected to the mount 40. The rotational movement (and amount of rotation), of the mount 40 relative to the extender body 30 at the pivot 41 , is also controlled through the movement of the extender body 34 relative to the main body 20 (using the actuator 38). The actuators 38 and 48 may thus cooperate to produce desired rotation of the mount and/or lateral translation of the mount 40, according to requirements. By applying linear extension or retraction differentially between actuators 38 and 48, rotation of the mount 40 may be imparted.

The mount 40 in this example has a surface 45 against which the blade may bear against in use, and which can be manipulated by the positioner 200 for positioning the turbine blade. By rotation about the pivot 41 , thereby changing the angle b, the surface 45 is tilted about the horizontal axis P.

Turning now to Figures 3 and 4, there is generally depicted an installation assem bly 500 for a wind turbine using the tool 1 as described in relation to Figures 1 and 2.

The assembly 500 includes a tower 300 for the wind turbine and a rotatable hub 350 at the top end of the tower 300 to which wind turbine blades 400 are to be at-

P28549PC00 Description and claims tached. The hub is rotatable about the axis 330 of the tower. The tower 300 is arranged in upright configuration extending vertically upward from an installation surface, e.g. the ground, deck, or other foundation 510. The tool 1 is mounted on the tower 300 and the blade 400 is attached to the mount 40, so as to be supported by the tool on the tower. The tool 1 is positioned be tween the side of the tower 300 and the blade 400, supporting the blade 400 so that the blade is arranged alongside the tower and spaced away from the tower by the tool 1. In Figures 3 and 4, the surface 45 of the mount 40 is approximately vertical so that the blade 400, which is held against the surface 45 by an gripping arrangement (not shown), is aligned along the mast in an initial configuration. In this configuration, a central longitudinal axis 440 of the blade 400, or an axis 441 normal to a connection face 470 at an end of the blade 400, is vertical and parallel with the central longitudinal axis 330 of the tower 300.

The blades 400 are typically arranged on the tower 300 using the tool 1 in this configuration also during transport to the installation site and/or before the tower is erected as seen in Figure 3. The tool 1 is thus typically mounted on the tower 300 and the blades 400 attached to the tool 1 with the tower lying horizontally.

In Figure 5, the installation assembly 500 is shown at a later point in time, where the tool 1 operates using the various actuators 28, 38, 48 to move the blade 400 with respect to the tower toward an installation position. In this configuration, the extender body 30 has moved laterally out of the main body 20, away from the side of the tower, and the mount 40 has pivoted outwardly about the horizontal axis P to open and increase the angle b further. This tilts the blade 400 which is at tached to the mount 40 so that the blade tip is moved away from the tower and the connecting, root end of the blade is moved toward the tower 300. The connecting end with the connection face 470 is brought toward alignment for attaching the blade to the hub 350. As can be seen, in this configuration of Figure 5, the blade is positioned such that the axis 441 is arranged at an acute angle a with respect to vertical and/or a defined longitudinal axis of the tower.

P28549PC00 Description and claims In order to attach the blade, full alignment of the connection end of the blade with the hub is typically required in a predetermined installation position. For example, the connecting face 470 of the blade may be required to be positioned parallel with a corresponding connecting face 370 of the hub 350. The face 470 of the blade may also need to be brought into sufficiently close proximity to the corresponding face 370 to allow connections to be made.

The tool in Figure 5 is shown before the actuator 28 is used to move the positioner 200 upward. The positioner 200 may be moved upward along the tower in a fur- ther step to bring the end of the blade closer toward the hub.

It can also be appreciated that during the installation process, one blade 400 is attached at a time (using the tool). After one blade is attached, the attached blade is then moved out of the way by rotating the nose portion of the hub 350 about a horizontal axis as indicated by arrow Fte. The hub 350 is then rotated with respect to the tower 300 about a vertical axis as indicated by arrow Ri to position a next connector 370 of the hub above the end of the next blade to be connected. The tool 1 which supports the next blade is then utilized in the same way to position it in correct alignment to allow it to be connected the next connector of the hub 350.

It can be noted that the tool 1 carries a winch 50 which is tethered by winch wire 53 to the tower 300 at a location F above. After the blade 400 has been attached, the support 100 can be disconnected by remote operation of the connectors 1 1 a, 1 1 b, (for example, by electric or hydraulic deactivation), leaving the tool 1 tethered to the tower by the winch wire 53. The winch can then be operated to spool out the wire 53 from the winch 50 to lower the tool 1 downward along the tower to re trieve it. The winch is supported on the main body 20.

Operation of the actuators may be electric, hydraulic, mechanical, or combinations thereof. The connectors may be activated by hydraulic or electric control to apply sufficient connecting force to solidly connect the support 100 to the tower 300 and supporting the blade 400 in use. As seen in various figures, the connectors 1 1 a,

P28549PC00 Description and claims 1 1 b can engage against a corresponding lug, groove, notch, or other formation on surface of the side of the tower.

In Figures 6 and 7, the manner in which the tool 1 may be employed in operational use to engage with the tool and position it into the installation position can be ap preciated further. In particular, the tool 1 in Figures 6 and 7 has a modified mount 840 which includes a gripping device 846 for gripping onto the blade 400.

In use, the positioner 200 is operated to provide movement relative to the support 100 and the tower 300 for aligning the blade 400 in the installation position. The actuators 38 and 48 are used for generating linear movement of the mount 40, 840 laterally away from the tower 300, and rotational movement of the mount about a horizontal axis. The actuator 28 is used for generating linear movement of the mount 40, 840 (and the positioner as a whole) along the tower 300.

It will be appreciated from the foregoing that the positioner 200 may take other forms in other variants of the invention, yet still provide corresponding movability with respect to the support 100 to position and align the blade appropriately for attachment to the hub. For example, a scissor structure could be envisaged. In other variants, for example, angular movement for tilting the blade may be ob tained by an angular coupling between parts proximal to the tower, e.g. between the support and the main body 20, while upward translational movement may be achieved by parts distal from the tower, e.g. between the main body and the mount. The support 100 may also take other forms. The tool 1 is described is implemented using linear actuators, and framework capable of taking and transfer ring structural loads effectively. This can facilitate efficient and robust installation and alignment procedure for the installation of wind turbines.

Various modifications and improvements may be made without departing from the scope of the invention herein described.

P28549PC00 Description and claims