Use of laminated structure in busbar system of wind turbine and wind turbine

Abstract

The present invention relates to the use of a laminated structure (1) of a conductive layer (4) and an insulating layer (6) as a busbar (110) in a busbar system (100), the laminated structure (1) comprising a plurality of contact holes (8) penetrating one or more conductive layers (4) of the laminated structure (1), wherein each contact hole (8) comprises a conductive pin (10) and an insulating sleeve (8a) arranged therein, the conductive pin (10) contacting the associated conductive layer (4) with one end and extending to the outside of the laminated structure (1) with a second end, the busbar (110) being used to mount a phase power converter (120) for converting AC current supplied by a generator (130) into AC current for a power grid (300), the busbar system (100) being accommodated in a nacelle (210) of a wind turbine (200). The present invention further relates to a wind turbine (200) comprising such a busbar system (100).

Description

Technical Field

[0001] The invention relates to the use of a laminated structure in a busbar system of a wind turbine and to a wind turbine comprising such a busbar system. Background Art

[0002] Multiphase busbars are used in switchgear to conduct and distribute alternating current to different electrical devices, which are usually installed in a switchgear cabinet. In order to provide the possibility to conduct all three phases or even more phases of an alternating current in a single busbar, multiphase busbars have been developed, which include a cover layer and a base layer of electrically insulating material, between which two or more layers of conductive sheet metal (in particular copper) are arranged, the two or more layers of the conductive sheet metal being electrically insulated from each other by means of an insulating intermediate layer.

[0003] A busbar of the above description is described in DE 102005015945 B4 of the applicant, in which the different layers are laminated to each other by means of a liquid resin. The laminated busbar has the advantage that it is dense and does not tend to delaminate due to repulsive forces that can be generated by the alternating currents conducted in the different conducting layers, which, if a short circuit occurs, can be in the range of several kiloamperes (kA).

[0004] A wind turbine typically includes a rotor that drives a generator that generates an AC current when the rotor rotates, the frequency and electrical output power of which depend greatly on the strength of the wind. To compensate for variations in frequency and electrical power, the generator is connected to the input side of a phase power converter that converts the AC output power of the generator into DC power. The DC power is again converted into AC power with a frequency that matches the frequency of the grid to which the wind power generator is connected.

[0005] The generator and the phase power converter connected thereto are located in the nacelle of the wind turbine, which is rotatably mounted at the end of a tower at a height of, for example, 50 m or more above the ground. In order to optimize the air flow through the rotor, it is desirable to reduce the size of the nacelle. This in turn requires that the space required for the electrical wiring connecting the generator, wind power converter and other electrical components be minimized.

[0006] One of the main reasons for the space required by electrical components in the nacelle of a wind turbine is that, when the turbine is in operation, the electrical supply lines and components dissipate a large amount of heat due to the high currents produced by the generator, which have to be converted to the higher voltage level of the grid to which the wind turbine is connected. Summary of the invention

[0007] Accordingly, the object of the present invention is to propose a new use of the known laminated structures which allows a denser design and an improved dissipation of thermal energy of the electrical components and busbar systems housed in the nacelle of a wind turbine.

[0008] This object is achieved by the use of a laminate structure claimed in the present invention. Specifically, the laminate structure of conductive layers and insulating layers according to the present invention is used as a busbar in a busbar system, the laminate structure includes a plurality of contact holes penetrating one or more conductive layers of the laminate structure, wherein each contact hole includes a conductive pin and an insulating sleeve arranged therein, the conductive pin contacts the associated conductive layer with one end and extends to the outside of the laminate structure with a second end, the busbar is used to install a phase power converter, the phase power converter is used to convert the AC current supplied by the generator into the AC current of the grid, and the busbar system is accommodated in the nacelle of the wind turbine. The laminate structure includes a first laminate substructure and a second laminate substructure electrically insulated from each other, wherein the first laminate substructure is suitable for being electrically connected to the grid and to the output terminal of the first circuit breaker, and the second laminate substructure is suitable for being connected to the output side of the phase power converter and to the input terminal of the first circuit breaker. The phase power converter and at least the first circuit breaker and / or further electrical components including capacitors and / or inductors are mounted to conductive pins extending out of the contact holes on the same side of the laminate structure. The laminate structure comprises a front side formed of an insulating material to which the phase power converter is mounted, and a conductive rear side formed of an uncoated layer of a metal sheet electrically connected to a protective ground of the power grid. Preferably, each conductive layer of the second laminate substructure is adapted to be electrically connected to an associated input terminal of the first circuit breaker by at least two connecting pins, and each conductive layer of the first laminate substructure is electrically connected to an associated output terminal of the first circuit breaker by at least two conductive pins adapted to contact an associated conductive layer of the first laminate substructure. Each of the at least two conductive pins connected to a conductive layer is electrically connected to each other by a common distribution bar. The laminate structure comprises a third laminate substructure electrically insulated from the first laminate substructure and the second laminate substructure, wherein the third laminate substructure is adapted to be electrically connected to a plurality of input terminals of a generator and a second circuit breaker, and the second laminate substructure is adapted to be connected to an input side of the phase power converter and to an output terminal of the second circuit breaker. Each conductive layer of the third laminate substructure is electrically connected to an associated input terminal of the second circuit breaker by at least two conductive pins contacting the conductive layer, and each conductive layer of the second laminate substructure is electrically connected to an associated output terminal of the second circuit breaker by at least two conductive pins adapted to contact an associated conductive layer of the second laminate substructure.Each of the at least two conductive pins connected to the conductive layer are electrically connected to each other via a common distribution bar.The laminate structure is arranged in a switchgear located inside the nacelle of the wind turbine.

[0009] Another object of the invention is to provide a wind turbine with a nacelle which allows a more compact and cost-effective design.

[0010] This object is achieved by a wind turbine as claimed in the present invention. Specifically, a wind turbine of the present invention comprises a rotor, a nacelle and a generator coupled to the rotor, wherein the generator and a phase power converter for converting an AC current supplied by the generator into an AC current of a power grid are housed in the nacelle, wherein the generator and the phase power converter are electrically connected to a busbar system located inside the nacelle. The busbar system comprises a busbar for mounting the phase power converter, which comprises a laminated structure of a conductive layer and an insulating layer, the laminated structure having a plurality of contact holes penetrating one or more conductive layers of the laminated structure, and each contact hole comprises a conductive pin and an insulating sleeve arranged therein, the conductive pin contacts the associated conductive layer with one end and extends to the outside of the laminated structure with a second end. The laminated structure comprises a first laminated substructure and a second laminated substructure electrically insulated from each other, wherein the first laminated substructure is suitable for being electrically connected to the power grid and electrically connected to an output terminal of a first circuit breaker, and the second laminated substructure is suitable for being connected to the output side of the phase power converter and to an input terminal of the first circuit breaker. The phase power converter and at least the first circuit breaker and / or further electrical components including capacitors and / or inductors are mounted to conductive pins extending out of the contact holes on the same side of the laminate structure. The laminate structure comprises: a front side, the front side being formed of an insulating material, the phase power converter being mounted to the front side; and a conductive rear side, the conductive rear side being formed of an uncoated layer of a metal sheet, the uncoated layer being electrically connected to the protective ground of the power grid. Preferably, each conductive layer of the second laminate substructure is adapted to be electrically connected to an associated input terminal of the first circuit breaker by at least two connecting pins, and each conductive layer of the first laminate substructure is electrically connected to an associated output terminal of the first circuit breaker by at least two conductive pins, the at least two conductive pins being adapted to contact an associated conductive layer of the first laminate substructure.

[0011] Each of the at least two conductive pins connected to the conductive layer is electrically connected to each other through a common distribution bar. The laminate structure includes a third laminate substructure electrically insulated from the first laminate substructure and the second laminate substructure, wherein the third laminate substructure is adapted to be electrically connected to a plurality of input terminals of the generator and a second circuit breaker, and the second laminate substructure is adapted to be connected to an input side of the phase power converter and to an output terminal of the second circuit breaker.

[0012] According to the present invention, a laminate structure of conductive layers and insulating layers is used as a busbar for mounting a phase power converter in a busbar system, the laminate structure comprising a plurality of contact holes penetrating one or more conductive layers of the laminate structure, and wherein each contact hole comprises a conductive pin and an insulating sleeve received therein, the conductive pin contacts the associated conductive layer with one end and extends to the outside of the laminate structure with its second end, the phase power converter is used to convert AC current supplied by a generator into AC current of a power grid, and the busbar system is accommodated in a nacelle of a wind turbine that supplies electrical energy to the power grid.

[0013] The present invention provides the advantage that the busbar system in which the laminated structure is used comprises a reduced weight and a more compact design compared to prior art busbar systems employing solid copper bars for wiring of electrical components in a nacelle of a known wind turbine.

[0014] A further advantage of the present invention can be seen in that the cost of wiring electrical components housed in the nacelle of a wind turbine can be significantly reduced due to the reduced amount of metal (particularly copper sheet material) employed to form the conductive layers in the laminate structure rather than the large amounts of copper strips used in the prior art.

[0015] Furthermore, the invention allows for improved safety for operators working in the nacelle of a wind turbine due to the inherent electrical insulation of the different conductive layers of the laminated structure, as well as the option for electrically insulating also the front side of the sandwich structure from the rear side by simply attaching an additional layer of insulating material if desired. In the same way, if the laminated structure is housed in an aeriated housing of insulating material (particularly a switchgear box formed of insulating material inside the nacelle) without an insulating outer layer, the overall cooling surface for dissipating the thermal energy generated by the electrical components and the electric current running through the different conductive layers can be enlarged. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention is described below with reference to the accompanying drawings.

[0017] Figure 1is a schematic view of a nacelle of a wind turbine showing a generator and further electrical components connected to a laminate structure used as a busbar in a busbar system housed in the nacelle,

[0018] Figure 2 yes Figure 1 Schematic cross-sectional view of a busbar of a busbar system,

[0019] Figure 3 is a 3-dimensional view of an exemplary embodiment of a circuit breaker which is mounted to a busbar of a busbar system having three input and three output conducting layers by means of five contact pins per phase, which extend to the front side of the laminate structure of the busbar and which are electrically coupled to corresponding terminals of the circuit breaker by means of distribution bars, and

[0020] Figure 4 yes Figure 1 and Figure 2 A cross-sectional view of a busbar showing output terminals of a first circuit breaker. DETAILED DESCRIPTION

[0021] like Figure 1 As shown in FIG. 1 , the wind turbine 200 includes a rotor 202 driving a generator 130 located inside a nacelle 210 that is rotatably mounted at an upper end of a tower 204 of the wind turbine 200. The generator 130 is connected to a phase power converter 120 that converts the AC current of the generator 130 to an AC current supplied to the grid 300. In order to increase the voltage supplied by the generator 130 to a higher level, a transformer 160 may be housed in the nacelle of the wind turbine 200 or alternatively in the tower 204.

[0022] If available from Figure 2 , Figure 3 and Figure 4 As seen in further detail, the electric power supplied by the generator 130 for each phase L1, L2, L3 via the electrical supply lines is fed to the laminated structure 1, which is used as a busbar 110 in the busbar system 100 of the wind turbine 200, to which the phase power converter 120 and other electrical components are mounted. The electrical composite may combine a first circuit breaker 140 and a second circuit breaker 150, which may be controlled by a control unit 170 of the wind turbine 200 or a control unit 170a of the phase power converter 120, so as to interrupt the supply of electric power from the phase power converter 120 to the grid 300 and / or from the generator 130 to the phase power converter 120 if a fault occurs.

[0023] To connect the phase power converter 120 and other electrical components such as circuit breakers 140, 150 and / or capacitors and inductors (which are not utilized Figure 2 The conductive layer 4 and the insulating layer 6 of the laminate structure 1 include a plurality of contact holes 8 that penetrate one or more conductive layers 4 of the laminate structure 1, such as Figure 4 Each contact hole 8 comprises an insulating sleeve 8a which prevents electrical short circuits of adjacent conductive layers 4, each of which conducts a different phase of the current supplied by the generator 130 or fed to the grid 300 after conversion by the phase power converter 120. A conductive pin 10 is arranged in each of the contact holes 8, the conductive pin 10 contacting the associated conductive layer 4 with one end and extending to the outside of the laminate structure 1 with a second end, as shown in detail in FIG. Figure 4 As indicated in relation to the laminate structure 1 having three conductive layers 4 to which the input terminal 140a of the circuit breaker 140 is connected. Figure 4 As further shown in FIG. 1 , additional contact holes may be formed on opposite sides of the circuit breakers 140 , 150 , which may receive conductive pins for mounting additional electrical components (not shown).

[0024] According to another aspect of the present invention, the laminate structure 1 may include a first laminate substructure 1a and a second laminate substructure 1b, the first laminate substructure 1a and the second laminate substructure 1b being electrically insulated from each other, such as Figure 2 and Figure 3 The first laminated substructure 1a is adapted to be electrically connected to the grid 300 and to the output terminal 140b of the first circuit breaker 140, while the second laminated substructure 1b is adapted to be connected to the output side 120b of the phase power converter 120 and to the input terminal 140a of the first circuit breaker 140 at the same time.

[0025] Preferably, the first circuit breaker 140 , which represents the main circuit breaker of the wind turbine 200 , is a known prior art air circuit breaker comprising at least three input and three output terminals 3 .

[0026] In order to reduce the resistance of the electrical connection between the associated input terminal 140a of the first circuit breaker 140 and each conductive layer 4, each conductive layer 4 of the second laminated substructure 1b is preferably electrically connected to the associated input terminal 140a of the first circuit breaker 140 by at least two connecting pins 10 (for example, by 5 conductive pins 10), and the at least two connecting pins 10 are preferably connected to each other by a common distribution bar 12, as shown in FIG. Figure 3Furthermore, in this embodiment, each conductive layer 4 of the first laminate substructure 1a is electrically connected to an associated output terminal 140b of the first circuit breaker 140 by at least two conductive pins 10 adapted to contact the associated conductive layer 4 of the first laminate substructure 1a.

[0027] Although the first laminated substructure 1a and the second laminated substructure 1b may be provided as two busbars 1, the two busbars 1 are physically connected by a lateral separation gap 6a between the input terminal 140a and the output terminal 140b of the first circuit breaker 140, as shown in FIG. Figure 2 Schematically indicated in FIG. 1 , but there is also the option of providing the busbar 110 as a laminated structure 1 in which the conductive layers 4 are internally separated by insulating gaps 6a filled with known insulating materials, which extend along the entire plane of the conductive layers 4, as shown in FIG. Figure 3 As indicated in .

[0028] According to a further embodiment of the present invention, the laminate structure 1 may include a third insulator structure 1c, which is electrically insulated from the first laminate substructure 1a and the second laminate substructure 1b in the same manner as previously described herein with respect to the first laminate substructure 1a and the second laminate substructure 1b. Figure 2 The third laminated substructure 1c shown in the figure can be electrically connected to the generator 130 and simultaneously electrically connected to a plurality of input terminals 150a of the second circuit breaker 150, which is electrically arranged between the generator 130 and the input side 120a of the phase power converter 120. In this embodiment, the second laminated substructure 1b is further adapted to be connected to the input side 120a of the phase power converter 120 and simultaneously connected to the output terminal 150b of the second circuit breaker 150. Although not shown in the drawings, the second laminated substructure 1b may further include an insulating separation gap 6a for electrically separating the input side 120a from the output side 120b.

[0029] In this embodiment, each conductive layer 4 of the third laminated substructure 1c is electrically connected to an associated input terminal 150a of the second circuit breaker 150 by at least two conductive pins 10, which are preferably interconnected by a common distribution bar 12, as has been previously described herein with respect to the first main circuit breaker 140, and the at least two conductive pins 10 contact the associated conductive layer 4. In this embodiment, each conductive layer 4 of the second laminated substructure 1b is electrically coupled to an associated output terminal 150b of the second circuit breaker 150 by at least two conductive pins 10, which are preferably electrically coupled by a common distribution bar 12, and the at least two conductive pins 10 are adapted to contact the associated conductive layer 4 of the second laminated substructure 1b, as has been previously described herein with respect to the first main circuit breaker 140. Figure 3 As shown in .

[0030] According to another aspect of the present invention, the phase power converter 120 and at least the first circuit breaker 140 and preferably also the like Figure 1 and Figure 2 Further electrical components such as capacitors and / or inductors as indicated in can be mounted to the conducting pins 10 of the busbar 110 which extend out of the contact holes 8 on the same side of the laminate structure 1. This provides an even cooling surface on the rear side of the busbar 110.

[0031] According to another object of the present invention, the laminate structure 1 is a flat structure comprising a front side, which is formed of an insulating material or covered with such an insulating material, from which conductive pins 10 for mechanically mounting the phase power converter 120 and any other electrical device protrude. The flat laminate structure of this embodiment may further include an electrically conductive back side, which may be formed by an uncoated layer of a metal sheet, preferably copper, which is electrically connected to the protective ground of the power grid 300 in order to dissipate the thermal energy generated in the conductive layer 4 of the laminate structure 1. The laminate structure 1 forming the busbar of the busbar system 100 may be directly coupled to the frame of the switchgear 400 or the nacelle 210 in order to mechanically hold the electrical components and at the same time provide efficient supply of the electrical components with electrical power.

[0032] The laminate structure 1 is preferably arranged in a switchgear 400 which is located inside a nacelle 210 of a wind turbine 200 and may form a rear wall or a side wall of the switchgear 400 .

[0033] List of reference numbers

[0034] 1Laminated structure

[0035] 1a The first substructure

[0036] 1b Second substructure

[0037] 1c The third substructure

[0038] 4 Conductive layer

[0039] 6 Insulation layer

[0040] 8 contact holes

[0041] 8a Insulation sleeve

[0042] 10 Conductive pins

[0043] 12 allocation strips

[0044] 100 Busbar System

[0045] 110 manifold

[0046] 120-phase power converter

[0047] Input side of 120a phase power converter

[0048] Output side of 120b phase power converter

[0049] 130 Generator

[0050] 140 First Circuit Breaker

[0051] 140a Input terminal of the first circuit breaker

[0052] 140b Output terminal of the first circuit breaker

[0053] 150 Second Circuit Breaker

[0054] 150a Input terminal of the second circuit breaker

[0055] 150b Output terminal of the second circuit breaker

[0056] 160 Transformer

[0057] 170 control unit

[0058] 170a control unit for controlling a phase power converter

[0059] 200 wind turbines

[0060] 202 rotor

[0061] 204 Tower

[0062] 210 Cabin

[0063] 300 Power Grid

[0064] 400 switchgear

[0065] L1 to L3 AC current phase

Claims

1. A use of a laminate structure (1) of a conductive layer (4) and an insulating layer (6) as a busbar (110) in a busbar system (100), the laminate structure (1) comprising a plurality of contact holes (8) penetrating one or more conductive layers (4) of the laminate structure (1), wherein each contact hole (8) comprises a conductive pin (10) and an insulating sleeve (8a) arranged therein, the conductive pin (10) contacting the associated conductive layer (4) with one end and extending to the outside of the laminate structure (1) with a second end, the busbar (110) being used to mount a phase power converter (120) for converting AC current supplied by a generator (130) into AC current of a power grid (300), the busbar system (100) being accommodated in a nacelle (210) of a wind turbine (200), The laminated structure (1) comprises a first laminated substructure (1a) and a second laminated substructure (1b) which are electrically insulated from each other, wherein the first laminated substructure (1a) is adapted to be electrically connected to the power grid (300) and to be electrically connected to an output terminal (140b) of a first circuit breaker (140), and the second laminated substructure (1b) is adapted to be connected to an output side (120b) of the phase power converter (120) and to be connected to an input terminal (140a) of the first circuit breaker (140), The phase power converter (120) and at least the first circuit breaker (140) and / or further electrical components including capacitors and / or inductors are mounted to conductive pins (10) extending out of the contact holes (8) on the same side of the laminate structure (1), The laminate structure (1) comprises: a front side, the front side being formed of an insulating material, the phase power converter (120) being mounted to the front side; and a conductive rear side formed by an uncoated layer of sheet metal, the uncoated layer being electrically connected to a protective ground of the electrical network (300).

2. The use according to claim 1, It is characterized in that Each conductive layer (4) of the second laminated substructure (1b) is adapted to be electrically connected to an associated input terminal (140a) of the first circuit breaker (140) via at least two connecting pins (10), and each conductive layer (4) of the first laminated substructure (1a) is electrically connected to an associated output terminal (140b) of the first circuit breaker (140) via at least two conductive pins (10), the at least two conductive pins (10) being adapted to contact the associated conductive layer (4) of the first laminated substructure (1a).

3. The use according to claim 2, Features Each of the at least two conductive pins (10) connected to the conductive layer (4) is electrically connected to each other via a common distribution bar (12).

4. The use according to any one of claims 1 to 3, Features The laminated structure (1) comprises a third laminated substructure (1c) which is electrically insulated from the first laminated substructure (1a) and the second laminated substructure (1b), wherein the third laminated substructure (1c) is adapted to be electrically connected to a plurality of input terminals (150a) of a generator (130) and a second circuit breaker (150), and the second laminated substructure (1b) is adapted to be connected to an input side (120a) of the phase power converter (120) and to an output terminal (150b) of the second circuit breaker (150).

5. The use according to claim 4, It is characterized in that Each conductive layer (4) of the third laminated substructure (1c) is electrically connected to an associated input terminal (150a) of the second circuit breaker (150) by at least two conductive pins (10) contacting the conductive layer (4), and each conductive layer (4) of the second laminated substructure (1b) is electrically connected to an associated output terminal (150b) of the second circuit breaker (150) by at least two conductive pins (10), the at least two conductive pins (10) being suitable for contacting the associated conductive layer (4) of the second laminated substructure (1b).

6. The use according to claim 5, Features Each of the at least two conductive pins (10) connected to the conductive layer (4) is electrically connected to each other via a common distribution bar (12).

7. The use according to any one of claims 1 to 3, Features The laminate structure (1) is arranged in a switchgear (400) located inside the nacelle (210) of the wind turbine (200).

8. A wind turbine (200) comprising a rotor (202), a nacelle (210) and a generator coupled to the rotor (202), the generator (130) and a phase power converter (120) for converting AC current supplied by the generator (130) into AC current for a power grid (300) being accommodated in the nacelle (210), wherein the generator (130) and the phase power converter (120) are electrically connected to a busbar system (100) located inside the nacelle (210), Features The busbar system (100) comprises a busbar (110) for mounting the phase power converter (120), comprising a laminated structure (1) of a conductive layer (4) and an insulating layer (6), the laminated structure (1) having a plurality of contact holes (8) penetrating one or more conductive layers (4) of the laminated structure (1), and each contact hole (8) comprising a conductive pin (10) and an insulating sleeve (8a) arranged therein, the conductive pin (10) contacting the associated conductive layer (4) with one end and extending to the outside of the laminated structure (1) with a second end, The laminated structure (1) comprises a first laminated substructure (1a) and a second laminated substructure (1b) which are electrically insulated from each other, wherein the first laminated substructure (1a) is adapted to be electrically connected to the power grid (300) and to be electrically connected to an output terminal (140b) of a first circuit breaker (140), and the second laminated substructure (1b) is adapted to be connected to an output side (120b) of the phase power converter (120) and to be connected to an input terminal (140a) of the first circuit breaker (140), The phase power converter (120) and at least the first circuit breaker (140) and / or further electrical components including capacitors and / or inductors are mounted to conductive pins (10) extending out of the contact holes (8) on the same side of the laminate structure (1), The laminate structure (1) comprises a front side formed of an insulating material to which the phase power converter (120) is mounted, and a conductive rear side formed of an uncoated layer of a metal sheet material, the uncoated layer being electrically connected to the protective ground of the power grid (300).

9. The wind turbine according to claim 8, Features Each conductive layer (4) of the second laminated substructure (1b) is adapted to be electrically connected to an associated input terminal (140a) of the first circuit breaker (140) via at least two connecting pins (10), and each conductive layer (4) of the first laminated substructure (1a) is electrically connected to an associated output terminal (140b) of the first circuit breaker (140) via at least two conductive pins (10), the at least two conductive pins (10) being adapted to contact the associated conductive layer (4) of the first laminated substructure (1a).

10. The wind turbine according to claim 9, Features Each of the at least two conductive pins (10) connected to the conductive layer (4) is electrically connected to each other via a common distribution bar (12).

11. A wind turbine according to any one of claims 8 to 10, Features The laminated structure (1) comprises a third laminated substructure (1c) electrically insulated from the first laminated substructure (1a) and the second laminated substructure (1b), wherein the third laminated substructure (1c) is adapted to be electrically connected to a plurality of input terminals (150a) of the generator (130) and a second circuit breaker (150), and the second laminated substructure (1b) is adapted to be connected to an input side (120a) of the phase power converter (120) and to an output terminal (150b) of the second circuit breaker (150).

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