US-12620869-B2 - Stator of an electric generator having a reinforcement structure

US12620869B2US 12620869 B2US12620869 B2US 12620869B2US-12620869-B2

Abstract

A stator for a wind turbine generator is provided, the stator including a first end plate and a second end plate spaced apart from each other in an axial direction of the wind turbine generator, and a reinforcement structure shaped as a plate and arranged between, and fixed to the first end plate and the second end plate, wherein the reinforcement structure is configured for coupling the first end plate and the second end plate, such that a force is transmissible between the first end plate and the second end plate.

Inventors

Saravanan Jayaraman
Simon Vyff JENSEN

Assignees

SIEMENS GAMESA RENEWABLE ENERGY A/S

Dates

Publication Date: 20260505
Application Date: 20220808
Priority Date: 20210813

Claims (14)

1 . A stator for a wind turbine generator, the stator comprising: a first end plate and a second end plate spaced apart from each other in an axial direction of the wind turbine generator; and a reinforcement structure shaped as a plate and arranged between, and fixed to the first end plate and the second end plate; and a separation element arranged between and fixed to the first end plate and the second end plate and coupled to the reinforcement structure, wherein the separation element extends from the first end plate to the second end plate wherein the reinforcement structure is configured for coupling the first end plate and the second end plate, such that a force is transmissible between the first end plate and the second end plate, wherein the reinforcement structure comprises: a first end section, which is fixed to the first end plate, and which has a first extension length along a first connection joint between the reinforcement structure and the first end plate; a second end section, which is fixed to the second end plate, and which has a second extension length along a second connection joint between the reinforcement structure and the second end plate; and a central section formed between the first end section and the second end section and having a maximum extension length smaller than at least one of the first minimum extension length and the second extension length; wherein the reinforcement structure comprises a single continuous plate forming the first end section, the central section, and the second end section.
2 . The stator according to claim 1 , wherein the plate has a thickness of 1 mm to 50 mm.
3 . The stator according to claim 1 , wherein the first end section tapers from the first connection joint towards the central section with respect to the first extension length, and wherein the second end section tapers from the second connection joint towards the central section with respect to the second extension length.
4 . The stator according to claim 3 , wherein the central section has a constant maximum extension length.
5 . The stator according to claim 1 , wherein the first end plate comprises a venting hole, the venting hole configured for enabling an air flow in an axial direction through the venting hole.
6 . The stator according to claim 5 , wherein the separation element is configured for forming a first compartment forming an air channel through the venting hole of the first end plate.
7 . The stator according to claim 6 , wherein the separation element is further configured for forming a second compartment forming a further air channel between the first end plate and the second end plate, wherein the further air channel is separated from the air channel by the separation element.
8 . The stator according to claim 5 , wherein the separation element is shaped as a flat plate, which lies on a plane substantially orthogonal to a plane of one of the first end plate and the second end plate, or which lies on a plane angled with respect to a plane of one of the first end plate and the second end plate; or wherein the separation element is shaped as a curved plate resembling a segment of a concentric circle around a central axis of rotation.
9 . The stator according to claim 8 , wherein the reinforcement structure is fixed to the first end plate and to the second end plate.
10 . The stator according to claim 1 , comprising at least one of the following features: wherein the stator comprises a diameter of 5 m to 20 m; wherein the reinforcement structure comprises a lightweight material.
11 . The stator according to claim 1 , wherein the stator comprises a plurality of reinforcement structures, wherein the reinforcement structures of the plurality of reinforcement structures are arranged radially in a circumferential direction around the central axis of rotation of the stator.
12 . The stator according to claim 10 , further comprising at least one blower device arranged between two reinforcement structures and configured for creating a cooling air flow.
13 . The stator according to claim 12 , wherein the blower device is mounted to the separation element for creating the cooling air flow in at least one of the first compartment and the second compartment.
14 . A method for reinforcing a stator of a wind turbine generator, the method comprising: arranging a first end plate and a second end plate spaced apart from each other in an axial direction of the wind turbine generator; arranging a reinforcement structure shaped as a plate between the first end plate and the second end plate; and fixing the reinforcement structure to the first end plate and to the second end plate, wherein a separation element is arranged between and fixed to the first end plate and the second end plate and coupled to the reinforcement structure, wherein the separation element extends from the first end plate to the second end plate; wherein the reinforcement structure couples the first end plate and the second end plate, such that a force is transmissible between the first end plate and the second end plate; wherein the reinforcement structure comprises: a first end section, which is fixed to the first end plate, and which has a first extension length along a first connection joint between the reinforcement structure and the first end plate; a second end section, which is fixed to the second end plate, and which has a second extension length along a second connection joint between the reinforcement structure and the second end plate; and a central section formed between the first end section and the second end section and having a maximum extension length smaller than at least one of the first minimum extension length and the second extension length; wherein the reinforcement structure comprises a single continuous plate forming the first end section, the central section, and the second end section.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to EP Application No. 21191230.8, having a filing date of Aug. 13, 2021, the entire contents of which are hereby incorporated by reference. FIELD OF TECHNOLOGY The following relates to a stator for a wind turbine generator having at least a reinforcement structure. Furthermore, the following relates to a method of reinforcing a stator for a wind turbine generator BACKGROUND An electric generator, such as an electric generator installed in a wind turbine, typically comprises a rotor which rotates relative to a stator. The stator normally comprises a frame body extending along a longitudinal central axis and including a stator yoke. End plates may be provided at the axial ends, which are also called the drive end and the non-drive end, respectively. The drive end (DE) is the longitudinal end facing the driving device (i.e., the rotor with blades of the wind turbine) and is spaced apart from the non-drive end (NDE) in an axial direction. The end plates mechanically support the stator frame body during manufacturing and operation. However, in the context of growing demand for renewable energies, the size (i.e., the diameter of rotor and stator) keeps increasing. Wind turbines should achieve the highest possible electrical output with the lowest possible weight and smallest possible dimensions of the generator housed in the tower head. However, ever growing demand for renewable energies, such as wind energy, requires increasingly large dimensions of the generator, and hence also of the stator of the generator. Therefore, there is a need to provide a robust design for a large stator of an electric wind turbine generator having one or more end plates, which design permits larger stator sizes by providing the necessary mechanical support. SUMMARY An aspect relates to a stator of an electric generator, in particular for a stator of a wind turbine generator. According to a first aspect of embodiments of the invention, there is provided a stator for a wind turbine generator, the stator comprising a first end plate and a second end plate spaced apart from each other in an axial direction of the wind turbine generator, and a reinforcement structure shaped as a plate and arranged between, and fixed to the first end plate and the second end plate, wherein the reinforcement structure is configured for coupling the first end plate and the second end plate, such that a force is transmissible between the first end plate and the second end plate. According to a further aspect of embodiments of the invention, there is provided a method for reinforcing a stator of a wind turbine generator, the method comprising i) arranging a first end plate and a second end plate spaced apart from each other in an axial direction of the wind turbine generator, ii) arranging a reinforcement structure shaped as a plate between the first end plate and the second end plate, and iii) fixing the reinforcement structure to the first end plate and to the second end plate, wherein the reinforcement structure couples the first end plate and the second end plate, such that a force is transmissible between the first end plate and the second end plate. In the context of the present document, the term “stator” may denote the immovable part of an electric generator, as has already been described above. A stator has an annular or cylindrical structure comprising for example magnetic elements and/or coil elements for generating electricity. Around the central axis, which corresponds to an axis of rotation of the driving device (i.e., the rotor), there is a (e.g., conical) hole in which there is sufficient room for the shaft and/or bearings of the rotor. The wind turbine generator may be designed with an external rotor rotating around an inner stator or an internal rotor being surrounded by the stator. In the context of the present document, the term “axial direction” may denote a direction (substantially) parallel to the direction of the axis of rotation of the rotor of the turbine, in particular of the wind turbine. The axis of rotation, hence the axial direction, is substantially orthogonal to a plane in which the end plates of the stator lie. In the context of the present document, the term “plate” may denote a flat, relatively thin piece of material, for example a forged, rolled, or cast metal in sheets of a certain thickness (other materials are possible). A plate, in the context of the present document, may have a main extension in two dimensions (or direction vectors) of a (geometric) plane, and the thickness along a third dimension, which is orthogonal to the plane, or, in other words, parallel to a normal vector that is orthogonal to the direction vectors of the plane. The main extension is usually much greater than the thickness. Although in its basic form, a plate may substantially have a rectangular shape with respect to the main extension, a plate in the context of this docume