PRE-FORMED COIL, WINDING STRUCTURE, AND STATOR FOR A GENERATOR OF A WIND TURBINE AND METHOD FOR PRODUCING A STATOR

Abstract

A form-wound coil of a stator of a generator of a gearless wind power installation is provided. The form-wound coil includes an electrical conductor with a first and a second terminal. The terminals are used serve in each case for electrical connection to a further form-wound coil. The terminals in each case have a thread for electrical connection using a screw. A winding structure, a stator having the form-wound coil, and a method for producing the stator are also provided.

Claims

1. A form-wound coil of a stator of a generator of a gearless wind power installation, comprising an electrical conductor including: a first terminal having a first thread for receiving a first screw and making an electrical connection to a respective further form-wound coil, and a second terminal having a second thread for receiving a second screw and making an electrical connection to a respective further form-wound coil.

2. The form-wound coil as claimed in claim 1, wherein the generator is a ring generator.

3. The form-wound coil as claimed in claim 1, wherein the first and second threads are internal threads.

4. The form-wound coil as claimed in claim 1, wherein at least one of: at least one of the first and second terminals of the form-wound coil is angled in relation to a coil longitudinal axis or in relation to a line parallel to the coil longitudinal axis, or at least another terminal of the first and second terminals is not angled in relation to the coil longitudinal axis or in relation to the line parallel to the coil longitudinal axis.

5. The form-wound coil as claimed in claim 1, wherein the electrical conductor has at least two layers and the at least two layers are each connected to each terminal, and the electrical conductor is a copper flat bar, a copper strip or a copper flat wire.

6. The form-wound coil as claimed in claim 1, wherein the electrical conductor of the form-wound coil has at least four windings.

7. The form-wound coil as claimed in claim 1, wherein the form-wound coil has one of at least three different forms, wherein the terminals of the at least three different forms are at different distances from a geometrical central point of the form-wound coil.

8. The form-wound coil as claimed in claim 1, wherein the electrical conductor or each layer of the electrical conductor of the form-wound coil is insulated using at least one of: lacquer, or powder coating.

9. The form-wound coil as claimed in claim 1, wherein the terminals are each soldered or welded to the electrical conductor.

10. The form-wound coil as claimed in claim 1, wherein the electrical conductor, in the region of connection to at least one terminal, has an insulation composed of glass-fiber-reinforced plastic for insulating at least one of: at least a part of the electrical conductor, or a part of the terminal, and the at least one terminals has spacers.

11. The form-wound coil as claimed in claim 1, wherein the electrical conductor and the first and second terminals are copper or copper alloy.

12. A winding structure of a stator of a generator of a wind power installation, comprising: a plurality of form-wound coils, wherein each form-wound coil of the plurality form-wound coils includes: an electrical conductor including: a first terminal having a first thread for receiving a first screw and making an electrical connection to a respective further form-wound coil, and a second terminal having a second thread for receiving a second screw and making an electrical connection to a respective further form-wound coil, wherein the winding structure includes a plurality of connecting elements, each connecting element being operative to electrically connect two terminals of two form-wound coils of the plurality of form-wound coils using screw connections.

13. The winding structure as claimed in claim 12, wherein the plurality of form-wound coils are interconnected such that the winding structure has a six phase configuration, wherein a first and a second strand are assigned to a first phase, a third and a fourth strand are assigned to a second phase, and a fifth and a sixth strand are assigned to a third phase.

14. The winding structure as claimed in claim 12, wherein the winding structure is divided into multiple segments, and identical phases of each segment are connected in parallel with one another.

15. The winding structure as claimed in claim 12, wherein a connecting element of the plurality of connecting elements includes one conductive connector having two apertures and two screws.

16. The winding structure as claimed in claim 12, wherein the plurality of connecting elements and the plurality of form-wound coils have a substantially identical coefficients of thermal expansion.

17. The winding structure as claimed in claim 15, wherein the conductive connector of the connecting elements has a U shape, and the form-wound coil has one of multiple different forms, wherein the different forms provide different lengths of terminal regions such that the plurality of connecting elements are arranged in groups.

18. The winding structure as claimed in claim 17, wherein the ends of the same side of U-shaped conductive connectors of one group are arranged, or connected to the form-wound coils, between the ends of the two sides of U-shaped conductive connectors of another group.

19. A stator of a generator of a wind power installation, comprising: a plurality of encircling grooves, wherein respectively adjacent grooves of the plurality of encircling grooves have a substantially equal spacing with one another, and the plurality of form-wound coils as claimed in claim 1, wherein the plurality of form-wound coils are inserted into the plurality of grooves.

20. (canceled)

21. A method for making a stator, comprising: inserting adjacent form-wound coils successively into grooves of the stator by at least: inserting a first predetermined number of the form-wound coils only partially into corresponding grooves or positioning the first predetermined number of the form-wound coils in front of the corresponding grooves, and inserting the first predetermined number of the form-wound coils into the corresponding grooves fully only together with a second predetermined number of the form-wound coils to be inserted last.

22. The method as claimed in claim 21, wherein a form-wound coil of the form-wound coils including two terminals each having one thread, and two terminals of different form-wound coils are connected using a conductive connector having two apertures, wherein, two screws are screwed through respective apertures into respective threads of the two terminals.

23. The method as claimed in claim 21, comprising: at least one of: grounding the two terminals and the conductive connector, or polishing the two terminals in a region of their contact surfaces before being connected by the conductive connector.

24. The method as claimed in claim 21, comprising: immersing the stator fully into a resin bath or liquid resin, and removing the stator from the resin bath or the liquid resin to allow resin adhering to the stator to cure.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0049] Further embodiments of the invention will emerge from the exemplary embodiments discussed in more detail on the basis of the drawings. In the drawing:

[0050] FIG. 1 shows a wind power installation,

[0051] FIG. 2 shows a schematic side view of a generator,

[0052] FIG. 3 shows a first view of a form-wound coil,

[0053] FIG. 4 shows a further view of a form-wound coil,

[0054] FIG. 5 shows a detail of a perspective view of a stator,

[0055] FIG. 6 shows a stator with six inserted form-wound coils,

[0056] FIG. 7 shows a plan view of an exemplary embodiment of a generator,

[0057] FIG. 8 shows a view, from the center of the stator, of the form-wound coils inserted into a stator, and

[0058] FIG. 9 shows a further perspective view of a stator.

DETAILED DESCRIPTION

[0059] FIG. 1 is a schematic illustration of a wind power installation. The wind power installation 100 has a tower 102 and a nacelle 104 on the tower 102. On the nacelle 104 there is provided an aerodynamic rotor 106 with three rotor blades 108 and a spinner 110. During the operation of the wind power installation, the aerodynamic rotor 106 is set in a rotational movement by the wind and thus also rotates a rotor of a generator, which is coupled directly or indirectly to the aerodynamic rotor 106. The electrical generator is arranged in the nacelle 104 and generates electrical energy. The pitch angles of the rotor blades 108 can be varied by means of pitch motors at the rotor blade roots 108b of the respective rotor blades 108.

[0060] FIG. 2 shows a generator 130 schematically in a side view. Said generator has a stator 132 and an electrodynamic rotor 134 mounted so as to be rotatable relative to said stator, and is fastened with its stator 132 to a machine support 138 by means of a journal 136. The stator 132 has a stator support 140 and stator laminated cores 142, which form stator poles of the generator 130 and which are fastened by means of a stator ring 144 to the stator support 140.

[0061] The electrodynamic rotor 134 has rotor pole shoes 146, which form rotor poles and which, by means of a rotor support 148 and bearing 150, are mounted on the journal 136 so as to be rotatable about the axis of rotation 152. The stator laminated cores 142 and rotor pole shoes 146 are separated by only a narrow air gap 154, which is a few mm thick, in particular less than 6 mm, but has a diameter of several meters, in particular more than 4 m.

[0062] The stator laminated cores 142 and the rotor pole shoes 146 form in each case one ring and, together, are also ring-shaped, such that the generator 130 is a ring generator. The electrodynamic rotor 134 of the generator 130 intentionally rotates together with the rotor hub 156 of the aerodynamic rotor, of which roots of rotor blades 158 are indicated.

[0063] FIG. 3 shows a view of an exemplary embodiment of a form-wound coil 10. The form-wound coil 10 has two limbs 12a, 12b. The limbs 12a, 12b run parallel to one another and have a length of greater than 90 cm. The two limbs 12a, 12b are interconnected at a first end 14 and at a second end 16.

[0064] The second end 16 of the form-wound coil 10 has a first terminal 18 and a second terminal 20. The terminals 18, 20 have an internal thread. Screws 22 are screwed into the internal thread of the terminals 18, 20. In relation to a coil longitudinal axis 24 or a line parallel to the coil longitudinal axis 24, the second terminal 20 is angled, and the first terminal 18 is not angled.

[0065] The form-wound coil 10 comprises a conductor 26 and the terminals 18 and 20, which are manufactured with copper. Furthermore, the screws 22 are manufactured with brass. The conductor 26 is composed of two layers of a flat wire, which are formed into four windings. That is to say, two layers of the flat wire, which is also referred to as copper flat wire, are connected to the two terminals 18, 20.

[0066] The form-wound coil 10 is thus formed with said two layers and four windings such that eight layers of the copper flat wire are arranged or stacked one above the other in the region of the limbs 12a, 12b and in the region of the first end 14.

[0067] Owing to the led-out terminals 18, 20, six layers remain arranged one above the other in the region of the second end 16. The copper flat wire is insulated by lacquering. In the connecting region of the conductor 26 to the terminals 18, 20, however, the insulation has been removed in order to connect the terminals 18, 20 to the conductor 26 by induction welding. In the region of the connection of the first terminal 18 to the conductor 26, a glass-fiber-reinforced plastic 28 is applied in order to re-insulate said part, which has had the insulation of the conductor 26 removed.

[0068] In an exemplary embodiment which is not illustrated, such a glass-fiber-reinforced plastic is also provided in the connecting part between the second terminal 20 and the conductor 26. In order that the form-wound coil 10 maintains its shape, the layers of the form-wound coil have been enwound in narrow regions. An insulation winding is however not provided.

[0069] FIG. 4 shows a further view of the form-wound coil 10, wherein here, the second end 16 with a part of the limbs 12a, 12b is illustrated from the side. The exemplary embodiment of the form-wound coil illustrated in FIG. 4 corresponds to the exemplary embodiment of the form-wound coil in FIG. 3.

[0070] FIG. 5 shows a perspective view of a stator 132 of a generator 130 of a wind power installation 100 with form-wound coils 10. The form-wound coils 10 have in each case one first terminal 18 and one second terminal 20. The first terminals 18 of the form-wound coils 10 are connected in each case to first terminals 18 of other form-wound coils 10. The same applies to the second terminals 20 of the form-wound coils 10.

[0071] The connections are produced by means of connecting elements 30. The connecting elements 30 may also be referred to as connecting lugs. The connecting elements 30 comprise in each case one flat bar 32, which has in each case one aperture at its end 34a, 34b. Said apertures are not visible in the illustration because screws 22 have been screwed through the apertures into the terminals 18, 20. The flat bars 32 have a U shape, such that every sixth first terminal 18 and every sixth second terminal 20 is connected by means of a connecting element 30 of said type, without the connecting element 30 being in contact with other terminals 18, 20 which are not intended to be connected to one another. The connecting elements 30 are therefore not insulated.

[0072] It can also be seen that the connecting elements 30 are arranged in different planes. This is possible because the terminals 18, 20 of adjacent form-wound coils 10 project to different extents.

[0073] The connecting elements 30 that are connected to the second terminals 20 have apertures which are spaced further apart from one another than the apertures of the connecting elements 30 connected to the first terminal 18. This is becauseproceeding from a center of the stator 132the second terminals 20 lie on a greater radius than the first terminals 18.

[0074] Furthermore, the flat bars 32 of the connecting elements 30 are of cranked or slightly angled form in order that the screws 22 can engage cleanly into the threads of the second terminals 20.

[0075] FIG. 6 shows an exemplary structure of a stator 132, into the grooves 38 of which six form-wound coils 10 are inserted. The form-wound coils 10 are connected to one another by means of connecting elements 30. Here, it is pointed out that the electrical connection is produced merely for the purposes of testing the production of the screw connection. The interconnection of the coils during later use differs from the connection configuration illustrated, and is accordingly merely exemplary. Specifically, the interconnection configuration illustrated in FIG. 6 involves a self-contained strand, that is to say a short circuit. Specifically, all twelve terminals of the six coils are connected to one another.

[0076] In the left-hand region of the figure, the laminated form of the stator 132 can also be seen in the grooves 38 not occupied by form-wound coils 10.

[0077] FIG. 7 is an illustration similar to FIG. 5, with a detail now being shown on an enlarged scale. Again, the form-wound coils 10 can be seen, which have in each case one first terminal 18 and one second terminal 20. The first terminals 18 have a spacer 40. The spacer 40 for the prevention of short circuits, specifically in order that adjacent first terminals 18 do not come into contact as a result of vibrations.

[0078] It can also be seen that adjacent form-wound coils have terminals 18, 20 that project to different extents. This yields a sawtooth-like profile of the heights of the terminals 18, 20. In the exemplary embodiment illustrated, the connecting elements 30 have, in addition to the flat bar 32 and the screws 22, disks 42 which improve the distribution of the force of the screw 22 into the flat bar 32 when said screw is screwed into the thread of the terminals 18, 20. Accordingly, a connecting element 30 according to a preferred exemplary embodiment has a flat bar 32, two screws 22 and two disks 42.

[0079] The spacers 40 correspond to a plastics strip with multiple bores through which multiple terminals 18, 20 are led in a spaced-apart manner before the connecting elements 30 are attached. Furthermore, a bundle of data lines 44 is illustrated, by means of which temperature sensors, for example, are connected to an evaluation devices.

[0080] FIG. 8 shows a side view, from the center of the stator, of the form-wound coils 10. Here, the abovementioned sawtooth-like profile of the terminals 18, 20, in this case of the first terminals 18, can be seen particularly clearly. In the left-hand half of the figure, it is possible to see first terminals 18 which are not connected to other terminals 18 by means of connecting elements 30. Said terminals 18 accordingly serve as terminals for connection to generator terminals (not illustrated).

[0081] FIG. 9 shows a further perspective view of a stator 132. Identical reference designations are used to denote identical features. FIG. 9 illustrates the arrangement of the connecting elements 30 in groups 60a, 60b. The conductive connectors 32 of the connecting elements 30 have a U shape, and the form-wound coils 10 are provided in three different forms with three different lengths of terminal regions 62a to 62c, such that the connecting elements 30 are arranged in groups of three 60a, 60b.

[0082] The ends of the same side of U-shaped conductive connectors 32 of one group 60b are arranged between the ends of both sides of U-shaped conductive connectors 32 of another group 60a. The stator can thus be realized with a particularly small space requirement in an axial direction.