WIND TURBINE WITH CABLE ARRANGEMENT

Abstract

A wind turbine includes a tower composed of a plurality of tower sections, and an upper section on top of the tower. The upper section has a nacelle and a rotor with rotor blades. The rotor is attached to the nacelle. The rotor blades are rotatable by wind around a horizontal rotor axis to drive a generator . The wind turbine includes a HV cable arrangement laid in the tower connecting a first HV component in the nacelle and a second HV component in a wind turbine tower bottom or foundation. The HV cable arrangement is divided into cable arrangement segments corresponding to the plurality of tower sections, where respective two of the cable arrangement segments are connected via a cable connection device such that the plurality of cable arrangement segments is connected in series to constitute the HV cable arrangement. The cable connection device includes a plate-based shielding.

Claims

1. A wind turbine, comprising a tower composed of a plurality of tower sections; an upper section on top of the tower, the upper section having a nacelle and a rotor with rotor blades, the rotor being attached to the nacelle and the rotor blades being rotatable by wind around a horizontal rotor axis to drive a generator in the nacelle; and a high voltage (HV) cable arrangement laid in the tower connecting a first HV component in the nacelle and a second HV component in a wind turbine tower bottom or foundation, the HV cable arrangement being divided into a plurality of cable arrangement segments corresponding to the plurality of tower sections, where respective two of the cable arrangement segments are connected via a cable connection device such that the plurality of cable arrangement segments is connected in series to constitute the HV cable arrangement; wherein the cable connection device comprises a plate-based shielding.

2. The wind turbine according to claim 1, wherein the cable connection device has a cabinet composed of a bottom panel, at least one side wall, and a top panel.

3. The wind turbine according to claim 2, wherein the cabinet is closed and has a maintenance door or flap for having access to an interior of the cabinet.

4. The wind turbine according to claim 2, wherein the cabinet comprises a pressure release mechanism.

5. The wind turbine according to claim 4, wherein the pressure release mechanism is in the bottom panel.

6. The wind turbine according to claim 4, wherein the pressure release mechanism comprises a perforated plate and/or an explosion hatch and/or a relief of over pressure.

7. The wind turbine according to claim 2, wherein the cabinet of the cable connection device comprises a first cable bushing through which a first cable arrangement segment is guided into an interior of the cable connection device and a second cable bushing through which a second cable arrangement segment is guided into the interior of the cable connection device, where the first cable arrangement segment and the second cable arrangement segment are electrically connected with each other using an end termination within the cable connection device.

8. The wind turbine according to claim 7, wherein the first cable bushing and the second cable bushing are in a same or different side panels of the cabinet.

9. The wind turbine according to claim 1, wherein the HV cable arrangement and each of the cable arrangement segments comprise a multi-phase cable, where all phases of respective two of the multi-phase cables are connected via the cable connection device.

10. The wind turbine according to claim 1, wherein the HV cable arrangement and at least one of the cable arrangement segments comprise a plurality of single-phase cables, where each phase of respective two of the single-phase cables are connected via a respective cable connection device.

11. The wind turbine according to claim 1, wherein each of the tower sections has an upper flange and a lower flange, the upper flange of a first tower section and the lower flange of a second tower section being fixed to each other thereby providing a platform in the tower, where the cable connection device is located on the platform.

12. The wind turbine according to claim 11, wherein the platform has one or more openings corresponding to the pressure release mechanism of the bottom panel.

Description

BRIEF DESCRIPTION

[0023] Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein

[0024] FIG. 1 shows in a partial cross-section, a wind turbine according to the present embodiment;

[0025] FIG. 2 shows a perspective view of a cable connection device according to the invention;

[0026] FIG. 3 illustrates a side view of the cable connection device according to FIG. 2, in which a side panel is removed;

[0027] FIG. 4 shows a bottom panel of the cable connection device of FIG. 2 from below;

[0028] FIG. 5 shows a perspective view of the cable connection device located on a platform of a not shown tower section; and

[0029] FIG. 6 shows a perspective view of the cable connection device located on a platform of a not shown tower section.

DETAILED DESCRIPTION

[0030] In the figures, like reference numerals designate like or functionally equivalent elements, unless otherwise indicated.

[0031] FIG. 1 shows an offshore wind turbine 1 according to an embodiment of the invention. The wind turbine 1 comprises a rotor 2 connected, via an energy conversion system to a transformer 5 arranged inside a nacelle 3. The energy conversion system which is not shown comprises a generator and a converter. The nacelle 3 is arranged on top of a tower 4 of the wind turbine 1. The rotor 2 comprises, for example, three rotor blades 9. The rotor blades 9 are connected to a hub 10 of the wind turbine 1. A shaft (not shown) connects the hub to the generator and the energy passes further through the converter and into the transformer 5.

[0032] The tower 4 is erected on a monopile 6 or any other type of foundation which is driven into a seabed 7 and is partly above the level of seawater 8. The monopile 6 constitutes a foundation of the wind turbine. The tower 4 may be connected, via a transition piece (not shown), to the foundation of the wind turbine.

[0033] The tower 4 comprises a plurality of sections 11, 12, 13, 14. In the present example, the tower 4 comprises a bottom tower section 11, two middle tower sections 12, 13, and a top tower section 14. By way of example only, the number of tower section corresponds to four. However, the number of tower sections may be higher or lower. The tower sections 11, 12, 13, 14 include each one or more upper flanges 15u bolted to a corresponding lower flange 15l of another tower section 11, 12, 13, 14. Further, the bottom tower section 11 of the tower 4 includes a flange 16 connected with the monopile 6.

[0034] The tower 4 comprises inside one or more platforms 17, 18, 19, 20. The platforms 17, 18, 19, 20 may be bolt platforms configured for a worker to bolt the corresponding tower sections 11, 12, 13, 14 to each other, as well as to the nacelle 3 and the monopile 6 when assembling the tower 4.

[0035] The transformer 5 constituting a first high voltage (HV) component is electrically connected to a second high voltage (HV) component (not shown) in the tower bottom or foundation of the wind turbine 1 by means of a HV cable arrangement 21. The HV cable arrangement 21 is divided into a plurality of cable arrangement segments 22, 23, 24, 25, 26. In the present embodiment, the plurality of cable arrangement segments 22, 23, 24, 25, 26 corresponds to the plurality of tower sections 11, 12, 13, 14 plus one as the transformer is placed within the nacelle 3 on top of the tower 4. However, the plurality of cable arrangement segments 22, 23, 24, 25, 26 can be less than the plurality of tower sections 11, 12, 13, 14.

[0036] Respective two of the cable arrangement segments 22, 23, 24, 25, 26 are connected via a cable connection device 27, 28, 29, 30 to each other. Each of the cable connection devices 27, 28, 29, 30 is located on a respective platform of the platforms 17, 18, 19, 20 such that the plurality of cable arrangement segments 22, 23, 24, 25, 26 is connected in series to constitute the HV cable arrangement 21 within the tower 4.

[0037] In the present example, the HV cable arrangement 21 and each of the cable arrangement segments 22, 23, 24, 25, 26 are a multi-phase cable, where all phases of respective two of the multi-phase cables are connected via the cable connection device 27, 28, 29, 30. Alternatively, and not illustrated in the figures, the HV cable arrangement 21 and each or a number of the cable arrangement segments 22, 23, 24, 25, 26 may comprise a plurality of single-phase cables, where each phase of respective two of the single-phase cables are connected via one or more respective cable connection devices.

[0038] Each of the cable connection devices 27, 28, 29, 30 comprises a plate-based shielding shaped as a metal plate-based box as illustrated in FIGS. 2 and 3. FIGS. 2 and 3 show the cable connection device 27 connecting the cable arrangement segments 22, 23 on platform 17 of tower section 11. The constitution of the other cable connection devices 28, 29, 29 corresponds to the embodiment described hereinafter.

[0039] As can be seen from the perspective view of FIG. 2, the cable connection device 27 has a cabinet 31. The cabinet 31 is composed of a bottom panel 32 (FIG. 3), sidewalls 33, 34, 35 and a top panel 37. The cabinet 31 is closed on all sides, except for the bottom. The top panel 37 has a maintenance door 38 or any other flap for having access to the interior of the cabinet 31. In the present example, the top panel 37 consists of two maintenance doors 38 being operable by respective door handles 39. Alternatively or additionally, the maintenance door(s) and/or flap(s) may be on one or more side panels 33, 34, 35. As a further alternative, the side panels 33, 34, 35 and/or the top panel 37 may be removable by means of unlocking screws or bolts with a tool or by removing locking or interlocking devices.

[0040] The cabinet 31 comprises a first cable bushing 41 and a second cable bushing 42. The first and second cable bushings are, by way of example only, arranged in the side panel 34. As can be seen from the side view of FIG. 3 in which the side panel 33 is removed, the cable arrangement segments 22, 23 are guided through the first and second cable bushings 41, 42. Respective ends of the cable arrangement segments 22, 23 are connected to end terminations 43, 44 such that the arrangement segments 22, 23 are connected in series with each other.

[0041] As can be seen from FIG. 3, the cable arrangement segments 22, 23 are mechanically fixed by clamps 46, 47 inside the cabinet 31. The end terminations 43, 44 may be HV end terminations according to known standards. The end terminations 43, 44 may be configured with a grounding profile 48. On the outside of the side panel 34 holding platforms 49, 50 are located below the first and second cable bushings 41, 42 to provide mechanical support to the cable arrangement segments 22, 23 when being guided into the interior of the cable connection device 27.

[0042] The platform 17, 18, 19, 20 has one or more openings in the area where the cabinet 31 and its bottom plate 32, respectively, are arranged. The bottom panel 32 comprises a pressure release mechanism 40 which can be seen from the bottom view of FIG. 4. Hence, the pressure release mechanism 40 in the bottom panel 32 corresponds to the one or more openings in the platform 17, 18, 19, 20 on which the cable connection device 27 is located.

[0043] The pressure release mechanism 40 may be in the form of a perforated plate as shown in FIG. 4. Alternatively or additionally, the pressure release mechanism 40 may comprise an explosion hatch and/or a relief of overpressure or a simple opening.

[0044] In event of an arc flash blast, this can be directed in a direction below the cable connection device 27. As the platform 17 is in the upper portion of the tower section 11, there is enough space within the tower section 11 through which the energy can be released without damaging components or causing danger to people being within the tower section 11.

[0045] As can be seen from the perspective views of FIGS. 5 and 6, the cable arrangement segments 22, 23 are guided through vertical struts 45 through the tower section. After having entered the adjacent tower section, the free end is guided through a respective cable bushing into the next cable connection device located in the adjacent tower section or being directly connected to a HV component further up or down the wind turbine or foundation.

[0046] The plate-based casing 31 facilitates the final installation of the HV cable arrangement 21 and provides a safe shield in the event of an arc flash accident during operation. The shielding of the cabinet 31 (casing) prevents access to the parts inside the cabinet 31, prevents against mechanical impact from the outside and controls the effects of faults inside the cabinet 31.

[0047] While the present embodiments have two cable arrangement segments entering the cabinet 31, the number of cable arrangement segments entering the casing 31 may be chosen different therefrom.

[0048] The described configuration enables pre-installing the HV cable arrangement segments in one or more pre-assembled structured tower sections and merge those at a given destination, i.e., at the offshore installation site. As an advantage from the ability to pre-manufacturing, assembly and test of the HV cable installation in the required tower sections may be made in an early part of the supply chain where these procedures are less costly than on the final wind turbine installation site. The pre-installed cable arrangement segments in the cable connection device allows for fast, safe, and easy assembly of the cable arrangement.

[0049] The cable connection device provides the advantage of a safe operational environment around the facility and controls the safety risk in the event of an arc flash scenario. The cable connection device can be installed on one or more locations in the wind turbine structure. The cable connection device covers cable end terminations, as well as the complete cable breakout (cable bushings). This greatly reduces the risk of damaging the equipment during installation.

[0050] Thus, installation flexibility and reduced costs are provided with the suggested wind turbine.

[0051] Although the present invention has been disclosed in the form of preferred embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0052] For the sake of clarity, it is to be understood that the use of “a” or “an” throughout this application does not exclude a plurality, and “comprising” does not exclude other steps or elements.