Field of invention

The present invention relates to a cable protection system for a wind turbine tower. The present invention also relates to a wind turbine tower and a wind turbine comprising such cable protection system.

Prior art

The green transition has increased the focus on renewable energy produced by using wind turbines, because wind turbines can create reliable, cost-effective, pollution-free energy. A reliable electrical connection from a generator to an external grid is essential for modern wind turbines.

Due to the large height of the wind turbine towers, an electrical cable hanging from the top end of a tower to the bottom end of the tower is exposed to large tensile forces induced by the weight of the cable itself.

Accordingly, it is desirable to have an efficient and robust way of protecting electrical cables inside a wind turbine tower.

It is an object of the present invention to provide a cable protection system for a wind turbine tower.

Summary of the invention

The object of the present invention can be achieved by a cable protection system for a wind turbine tower as defined in claim 1 and a method as described in claim 20. Preferred embodiments are defined in the dependent subclaims, explained in the following description and illustrated in the accompanying drawings.

The cable protection system according to the invention is a cable protection system for protecting one or more cables hanging inside a wind turbine tower, wherein the cable protection system comprises one or more strain-relieving members that comprise: one or more clamping members attached to the one or more cables, one or more wires attached to and hanging from an attachment member, one or more clamping members attached to the one or more wires and a mounting structure connected to the clamping members and to the clamping structures, wherein the attachment member is provided in the upper portion of the wind turbine tower and extends between two spaced apart points of attachment.

Accordingly, there is no need for attaching the wires to the wall of the wind turbine tower. This is a major advantage because the strength of the wall of the wind turbine tower can be maintained in this manner.

The cable protection system according to the invention makes it possible to provide a cable protection system for a wind turbine tower. The weight of the one or more cables will be transferred to the wires.

In one embodiment, the cables are electrical cables.

In one embodiment, the cables are liquid guiding hoses or pipes.

In one embodiment, the cables are gas guiding hoses or pipes.

In one embodiment, the cable protection system comprises a single strain-relieving member.

In one embodiment, the cable protection system comprises two strainrelieving members. In one embodiment, the cable protection system comprises three strain-relieving members.

In one embodiment, the cable protection system comprises four or more strain-relieving members.

The clamping members are configured to be attached to the one or more cables and hereby provide a firm fixation of the one or more cables to the clamping members.

In one embodiment, the one or more wires attached to and hanging from a single attachment member.

In one embodiment, the attachment member is a one-piece body.

In one embodiment, the clamping members are configured to be detachably attached to the one or more cables and hereby provide a firm fixation of the one or more cables to the clamping members. Hereby, the clamping members can be detached from the one or more cables. This may be an advantage when cables have to be replaced or serviced.

The wires may be made of metal.

In one embodiment, the wires are steel wires.

In one embodiment, the wires are fibre- reinforced plastic wires. The fibres may comprise carbon, aramid or glass.

The one or more clamping structures are attached to the one or more wires. The one or more clamping structures are configured to be attached to the one or more wires and hereby provide a firm fixation of the one or more wires to the clamping structures. In one embodiment, the one or more clamping structures are configured to be detachably attached to the one or more wires and hereby provide a firm fixation of the one or more wires to the clamping structures. Hereby, the clamping structures can be detached from the one or more wires. This may be an advantage when wires have to be replaced or serviced.

The mounting structure connected to the clamping members and to the clamping structures may have any suitable size and form.

In one embodiment, the one or more wires are attached to the attachment member in one or more points of fixation provided in a distance from the wall of the wind turbine tower. Hereby, impact from the cables towards the wall of the wind turbine tower can be avoided. Moreover, there is easy access to the cables during inspections, repair and replacement.

In one embodiment, the one or more points of fixation are spaced apart from the points of attachment. Hereby, it is possible to add additional cables or wires to the attachment member. Moreover, it can be ensured that that the cables are distanced from the wall of the wind turbine tower.

In one embodiment, the lower free end (distal end) of each of the one or more wires is attached to a fixation structure. Hereby, it is possible to secure the wires firmly in their lower free end (distal end).

In one embodiment, the fixation structure is attached to a wire tightening device.

In one embodiment, the fixation structure is part of a wire tightening device.

In one embodiment, the wire tightening device is attached to the floor or another component of a transition piece to which the wind turbine tower is attached. Hereby, it is possible to provide a reliable and efficient attachment of the one or more wires.

In one embodiment, the points of attachment are attached arranged symmetrically along the attachment member.

In one embodiment, the points of fixation are provided in a distance of at least 20 cm from the wall of the wind turbine tower.

In one embodiment, the points of fixation are provided in a distance of at least 30 cm from the wall of the wind turbine tower.

In one embodiment, the points of fixation are provided in a distance of at least 40 cm from the wall of the wind turbine tower.

In one embodiment, the points of fixation are provided in a distance of at least 50 cm from the wall of the wind turbine tower.

In one embodiment, the attachment member is a bar that is attached to the wind turbine tower.

In one embodiment, the attachment member is a solid bar that is attached to the wind turbine tower.

In one embodiment, the attachment member is a cylindrical bar.

In one embodiment, the cross-sectional area of the bar is circular. In one embodiment, the cross-sectional area of the bar is rectangular.

In one embodiment, the cross-sectional area of the bar is square.

In one embodiment, the cable protection system comprises a first wire and a second wire. Hereby, it is possible to provide a strong cable protection system. If one wire breaks, the other wire will still support the cables.

In one embodiment, the first wire and a second wire have the same size and form.

In one embodiment, the first wire and the second wire extend parallel to each other. This may be the case when the first wire and the second wire are hanging freely. This may, however, also be the case, if the distal end of the wires is fixed to a structure.

In one embodiment, the one or more cables are suspended between the first wire and the second wire. Hereby, it is possible to provide a reliable system that is easy to install, inspect and service.

In one embodiment, each cable is attached to a separate clamping member. Hereby, it is possible to mount, service and inspect the cables one by one without affecting the other cables.

In one embodiment, each cable is attached to a separate clamping structure. Hereby, it is possible to mount, service and inspect the wires one by one without affecting the other wires.

In one embodiment, each clamping member comprises a first portion and a second portion that are bolted together to form a structure provided with a through-going opening, through which a cable can extend, wherein the cable is clamped by the clamping member and hereby fixed to the clamping member when the first portion and a second portion are bolted together. Hereby, it is possible to provide a simple, reliable and user-friendly system.

In one embodiment, each clamping structure comprises a first element and a second element that are bolted together to form a structure provided with a through-going opening, through which a wire can extend, wherein the wire is clamped by the clamping structure and hereby fixed to the clamping structure when the first element and a second element are bolted together. Hereby, it is possible to provide a simple, reliable and user-friendly system.

In one embodiment, the mounting structure is a plate-shaped structure comprising attachment structures for attaching the clamping structures.

In one embodiment, the mounting structure is a plate-shaped structure comprising attachment structures for attaching the clamping members.

In one embodiment, the mounting structure is a plate-shaped structure comprising attachment structures for attaching the clamping structures and the clamping members.

In one embodiment, the clamping members are bolted to the mounting structure.

In one embodiment, the clamping structures are bolted to the mounting structure.

In one embodiment, the mounting structure is a plate-shaped structure comprising attachment structures for attaching the clamping structures.

In one embodiment, the mounting structure is a plate-shaped structure comprising attachment structures for attaching the clamping members.

In one embodiment, the clamping members are bolted to the mounting structure.

The clamping structures are bolted to the mounting structure.

It may be an advantage to have a wind turbine tower comprising a cable protection system according to the invention.

It may be an advantage to have a wind turbine comprising a wind turbine tower according to the invention.

The method according to the invention is a method for installing a cable protection system in a wind turbine tower, wherein the method comprises the step of applying a cable protection system according to the invention.

Description of the Drawings

The invention will become more fully understood from the detailed description given herein below. The accompanying drawings are given by way of illustration only, and thus, they are not limitative of the present invention. In the accompanying drawings:

Fig. 1A shows a side view of a wind turbine according to the invention;

Fig. IB shows a cross-sectional side view of the wind turbine shown in Fig. 1A;

Fig. 2 shows a cross-sectional view of a portion of a wind turbine according to the invention;

Fig. 3 shows a top view of the wind turbine shown in Fig. 1A;

Fig. 4 shows a cross-sectional view of a portion of a wind turbine according to the invention;

Fig. 5A shows a front view of a strain-relieving member according to the invention;

Fig. 5B shows a top view of the strain-relieving member shown in Fig. 5A and

Fig. 6 shows a cross-sectional side view of a wind turbine according to the invention and a cable protection system according to the invention mounted in a wind turbine tower.

Detailed description of the invention

Referring now in detail to the drawings for the purpose of illustrating preferred embodiments of the present invention, a jacket 2 of the present invention is illustrated in Fig. 1A.

Fig. 1A is a side view of a wind turbine according to the invention comprising a jacket 2 that comprises a jacket support structure 28 that is placed on feet 32 that are arranged on the seabed 8. The water level 10 is indicated and it can be seen that a major portion of the jacket support structure 28 is submerged into water.

The jacket support structure 28 comprises three legs 4 that are mechanically connected to each other by means of a plurality of cross members 12 that constitute a lattice structure. In a prior art jacket construction, the cross members 12 are attached to the legs by means of welding. In the jacket 2 according to the invention, however, the cross members 12 are attached to the legs.

It can be seen that the jacket 2 tapes towards its top portion. A transition piece 14 is attached to the top portion of the jacket support structure 28. The transition piece 14 is attached to the top portion of the jacket support structure 28.

A work platform and boat landing area 26 is provided at the transition piece 14. The work platform and boat landing area 26 extends from the central area of the transition piece 14 and protrudes horizontally from here.

A wind turbine tower 6 is attached to the transition piece 14 of the jacket 2. The tower 6 is attached to the transition piece 14 in a joint 24. The tower 6 is bolted to the transition piece 14.

Fig. IB illustrates a cross-sectional side view of the wind turbine shown in Fig. 1A. It can be seen that several electrical cables 50 extend from the top portion of the tower 6 to the bottom portion of the tower 6.

Fig. 2 illustrates a cross-sectional view of a wind turbine according to the invention comprising a jacket 2 having a transition piece 14. The transition piece 14 comprises an inner space, from which there is access to a ladder 58. A wind turbine tower 6 is supported by and attached to the transition piece 14. The transition piece 14 is attached to legs 4. It can be seen that cross members 12 are attached to the legs 4.

A work platform and boat landing area 26 is attached to the transition piece 14. In one embodiment, the work platform and boat landing area 26 is attached to the transition piece 14 by means of connection structures shaped as steel girders or steel bars 36 extending between the transition piece 14 and the work platform and boat landing area 26.

A person 34 is standing on the work platform and boat landing area 26. A railing 42 surrounds the work platform and boat landing area 2 to prevent personnel from falling.

A container module 40 is provided in the right-side end of the work platform and boat landing area 26. The container module 40 can be used to store equipment and spare parts.

Several electrical cables 50, 50', 50", 50"' are hanging along the inner wall of a wind turbine tower 6. The cables 50, 50', 50", 50"' extend along an area between a first wire 48 and a second wire 48' extending parallel to the first wire 48. The wires 48, 48' are arranged and configured to function as strain-relieving members arranged to protect electrical cables 50, 50', 50", 50'" hanging from the top portion to the bottom portion of the tower 6. The lower end (distal end) of the first wire 48 is attached to a first fixation structure 72. Likewise, the lower end (distal end) of the second wire 48' is attached to a second fixation structure 72'. Each of the fixation structures 72, 72' are part of a wire tightening device 74 that is fixed to the floor or another component of the transition piece 14. Accordingly, the wires 48, 48' can be tightened in order to keep the cables 50, 50', 50", 50'" in place. The use of a wire tightening device 74 can limit the horizontal displacement of cables 50, 50', 50", 50'".

The wires 48, 48' may also be used to function as strain-relieving members arranged to protect hoses for transporting cooling water to higher levels of the wind turbine tower.

Fig. 3 illustrates a top view of the wind turbine shown in Fig. 1A. The wind turbine comprises a jacket 2 comprising a jacket support structure 28 that is placed on feet 32 that are configured to be arranged on a seabed. The jacket 2 comprises a transition piece 14 that is attached to the top portion of the jacket support structure 28. The jacket support structure 28 comprises three legs 4 that are mechanically connected to each other by means of a plurality of cross members 12 constituting a lattice structure. The cross members 12 are attached to the legs 4.

A work platform and boat landing area 26 is provided at the transition piece 14. The work platform and boat landing area 26 extends from the central area of the transition piece and protrudes horizontally from here. A container module 40 is placed on the work platform and boat landing area 26.

Fig. 4 illustrates a cross-sectional view of a wind turbine according to the invention comprising a jacket 2 comprising transition piece 14. The transition piece 14 has an entrance 30 and an inner space providing access to a ladder 58, by which personnel can access the higher sections of a wind turbine tower 6 that is supported by and attached to the transition piece 14.

The transition piece 14 is mechanically connected to legs 4. Accordingly, the legs 4 and the transition piece 14 are bolted together. Moreover, cross members 12 are attached to the legs 4.

The jacket 2 comprises a work platform and boat landing area 26. The work platform and boat landing area 26 is attached to the transition piece 14 by means of connection structures comprising bars 36 extending between the transition piece 14 and the work platform and boat landing area 26. The connection structures constitute a U-shaped mounting construction. The work platform and boat landing area 26 comprises a plate-shaped platform suitable for being used as a working and transport section.

A person 34 is standing on the platform being surrounded by a railing 42 to prevent personnel from falling. It can be seen that a container module 40 is provided in the right-side end of the work platform and boat landing area 26. The container module 40 makes it possible to store equipment and spare parts.

The work platform and boat landing area 26 comprises a sliding system 38. The sliding system 38 comprises tracks 46, 46' arranged to allow equipment and objects to be transported along the tracks 46, 46' e.g. by using a slide vehicle configured to be moved along the tracks 46, 46'. It can be seen that the tracks 46, 46' extend through an area provided straight below the entrance 30. Hereby, it is possible to slide objects along the tracks 46, 46' into a position, at which the objects are placed below the entrance 30. From this position the objects can be lifted up through the entrance 30 and hereby enter the interior portion of the transition piece 14.

A plurality of holes 44 are exposed because one segment of the transition piece 14 has been removed (for illustrative purposes). The holes 44 are arranged and configured to receive bolts so that the segments of the transition piece 14 can be bolted together.

A first wire 48 and a second wire 48' extend along the inside wall of the tower 6. The wires 48, 48' are arranged and configured to function as strain-relieving members arranged to protect electrical cables hanging from the top portion to the bottom portion of the tower 6. This is shown in and explained with reference to Fig. 5A, Fig. 5B and Fig. 6. The lower end (distal end) of the first wire 48 is attached to a first fixation structure 72. Likewise, the lower end (distal end) of the second wire 48' is attached to a second fixation structure 72'. Each of the fixation structures 72, 72' are part of a wire tightening device 74 that is fixed to the floor or another component of the transition piece 14. The wire tightening device 74 is designed to tighten the wires 48, 48' in order to keep the cables 50, 50', 50", 50'" in place and reduce the horizontal displacement of cables 50, 50', 50", 50'".

Fig. 5A illustrates a front view of a strain-relieving member 60 according to the invention. Fig. 5B illustrates a top view of the strain-relieving member 60 shown in Fig. 5A. Four electrical cables 50, 50', 50", 50'" are hanging along the inner wall of a wind turbine tower 6. The cables 50, 50', 50", 50'" extend along an area between a first wire 48 and a second wire 48' extending parallel to the first wire 48. Each cable 50, 50', 50", 50"' is attached to a clamping member 54, 54', 54", 54'".

A first clamping structure 52 is fixed to the first wire 48, wherein a second clamping structure 52' is fixed to the second wire 48'. The clamping structures 52, 52' are attached to a mounting structure 62. In one embodiment, the mounting structure 62 is plate-formed.

The mounting structure 62 is attached to clamping members 54, 54', 54", 54'". Therefore, the load of the cables 50, 50', 50", 50'" (introduced by gravity) is transferred to the wires 48, 48' through the clamping members 54, 54', 54", 54'" via the mounting structure 62 to the clamping structures 52, 52'. The strain-relieving member 60 is provided to prevent each cable 50, 50', 50", 50'" from being exposed to large tensile forces induced by the weight of the cable itself.

The wires 48, 48' may be steel wires 48, 48'. The cables 50, 50', 50", 50'" may be semi-conductor or multi-conductor cables. A service lift 64 is provided next to the strain-relieving member 60. The service lift 64 is suspended in wires (not shown) allowing the service lift 64 to be vertically displaced. The service lift 64 comprises an opening or a door and is arranged adjacent to the cables 50, 50', 50", 50'" so that the cables 50, 50', 50", 50'" can be accessed through the opening or door and hereby serviced by a person inside the service lift 64.

Fig. 6 illustrates a cross-sectional side view of a jacket 2 according to the invention and a cable protection system 70 according to the invention mounted in a wind turbine tower 6. The jacket comprises a jacket support structure 28.

The jacket 2 comprises a jacket support structure 28 that comprises legs 4 that are mechanically connected to each other by means of a plurality of cross members 12. The cross members constitute a lattice structure. The cross members 12 are bolted to the legs 4.

The jacket 2 tapes towards its top portion, at which a transition piece 14 is provided. The transition piece 14 is bolted to the top portion of the jacket support structure 28. The tower 6 is attached to the transition piece 14 in a joint 24. The tower 6 is bolted to the transition piece 14.

A work platform and boat landing area 26 is attached to the transition piece 14. The work platform and boat landing area 26 extends from the central area of the transition piece 14 and protrudes laterally from the remaining part of the jacket support structure 28. The work platform and boat landing area 26 is attached to the transition piece 14 by means of connection structures 36. The connection structures 36 may be shaped as tubular structures or bars by way of example. A person 34' is standing on the work platform and boat landing area 26. A railing 42 prevents the person 34' from falling over.

An additional platform 65 is attached to one of the legs of the jacket support structure 28. A person 34" stands on this platform 65 and is protected from falling over by a railing 42. The platform 65 is connected to the work platform and boat landing area 26 through a ladder extending between the platform 65 and the work platform and boat landing area 26. In one embodiment, a separate platform 65 s provided for each joint between adjacent leg segments. Hereby, it is possible to service the joints.

A centrally arranged entrance 30 is provided at the transition piece 14. A person 34 has entered the inner space in the transition piece 14 through the entrance 30.

Two parallel tacks 46, 46' are provided at the work platform and boat landing area 26. The tracks 46, 46' extend through an area provided straight below the entrance 30. Accordingly, it is possible to slide objects along the tracks 46, 46' into a position, from which the objects are placed below the entrance 30. From this position the objects can be lifted up through the entrance 30 and hereby enter the interior portion of the transition piece 14.

Several cables 50, 50', 50", 50'" are hanging from a first high position (near the top of the tower 6) inside the tower 6 to a lower position near the bottom portion of the tower 6. The cables 50, 50', 50", 50'" are very heavy due to their large length. Accordingly, a cable protection system 70 comprising strain-relieving members 60 as the one shown and explained with reference to Fig. 5A and Fig. 5B is used to protect the cables 50, 50', 50", 50'". The cable protection system 70 comprises a first strain-relieving member 60 and a second strain-relieving member 60 that are attached to two parallel wires 48, 48' hanging from an attachment member 61 that is attached to the top portion of the tower 6.

The attachment member 61 is provided in the upper portion of the wind turbine tower 6 and extends between two spaced apart points of attachment A, A'. The wires 48, 48' are attached to the attachment member 61 in two points of fixation P, P' provided in a distance from the wall of the wind turbine tower 6. This prevents impact from the cables 50, 50', 50", 50'" towards the wall of the wind turbine tower 6. Furthermore, easy access to the cables during inspections, repair and replacement is achieved.

The points of fixation P, P' are spaced apart from the points of attachment A, A'. Accordingly, it is possible to add additional cables or wires to the attachment member 61. Moreover, it can be ensured that that the cables are distanced from the wall of the wind turbine tower 6.

In one embodiment, the lower free end (distal end) of each of the wires 48, 48' is attached to a fixation structure in order to secure the wires 48, 48' firmly in their lower free end (distal end).

A service lift 64 is provided next to the uppermost strain-relieving member 60. The service lift 64 is moveably mounted to be vertically displaced. The service lift 64 is provided with an opening and is arranged adjacent to the cables 50, 50', 50", 50'". Hereby the cables 50, 50', 50", 50'" can be accessed through the opening or door and hereby serviced by a person inside the service lift 64.

Inside the inner space of the transition piece 14, there is access to a ladder 58 extending along the cables 50, 50', 50", 50'".

List of reference numerals

2 Jacket

4 Leg

6 Tower

8 Seabed

10 Water level

12 Cross member

14 Transition piece

16 First structure

18 Second structure

22 Bolt

24 Joint

26 Work platform and boat landing area

28 Jacket support structure

30 Entrance

32 Foot

34, 34', 34" Person

36 Connection structure

38 Sliding system

40 Container module

42 Railing

44 Hole

46, 46' Track

48, 48' Wire

50, 50', 50", 50'" Cable

52, 52' Clamping structure

54, 54', 54", 54'" Clamping member

56 Mounting plate

58 Ladder

60 Strain-relieving member

61 Attachment member 62 Mounting structure

64 Service lift

65 Platform

66 Door

68 Opening

70 Cable protection system

72 Fixation structure

74 Wire tightening device