Grounding carbon brush device of large-shaft-diameter motor

Abstract

The invention provides a large-shaft-diameter motor grounding carbon brush device. The large-shaft-diameter motor grounding carbon brush device comprises a rotor main shaft; the grounding ring is arranged on the outer side of the rotor main shaft, and the grounding ring is provided with at least one mounting hole; the carbon brush assembly is arranged between the outer ring of the rotor main shaft and the inner ring of the grounding ring, the carbon brush assembly comprises at least one carbon fiber bundle, two end parts of the carbon fiber bundle are overlapped and connected in the same direction to form a fixing part, a bending part and a connecting part for connecting the bending part and the fixing part, and the fixing part is fixedly connected to the mounting hole and externally connected with the grounding end; at least part of the bending part is used for being in contact and conductive connection with a rotor spindle, and spindle current is introduced into the grounding end through the connecting part and the fixing part in sequence. The shaft electric corrosion prevention device can be in stable contact with a rotor main shaft for electric conduction, can reduce shaft voltage to realize a shaft electric corrosion prevention function, and is particularly suitable for large-shaft-diameter high-linear-speed motors.

Description

Technical Field

[0001] This application relates to the field of wind power technology, and more specifically, to a grounding carbon brush device for a large-diameter motor. Background Technology

[0002] The development and utilization of green, environmentally friendly, and clean energy has become an inevitable trend for future development. As a clean and renewable energy source, wind power has been vigorously developed in recent years.

[0003] As a core component of generator sets, wind turbines inevitably generate shaft currents during operation. The presence of shaft currents can damage the generator, such as causing bearing erosion, leading to premature bearing failure. Therefore, measures need to be taken to suppress shaft currents during the generator design phase.

[0004] Currently, the mainstream method for suppressing shaft current in wind turbines is to install grounding carbon brushes at either the driven or non-driven end of the shaft. Common grounding carbon brushes mainly come in two types: carbon blocks and conductive brushes. The first type, carbon block brushes, suffers from wear and requires regular inspection and replacement. After replacing the carbon block, pre-grinding is necessary to ensure effective contact between the brush and the shaft. Furthermore, conductive carbon powder is generated during use due to wear, requiring a collection box to collect the carbon powder and regular cleaning of any remaining carbon powder to prevent short circuits or creepage faults. Therefore, it is not suitable for motors with large shaft diameters and high surface linear speeds. The second type, carbon fiber brushes, uses a brush structure with point contact between the brush and the main shaft. This results in a small contact area and a small conductive contact surface. The brush head structure also leads to poor recovery stiffness. The cantilevered brush structure is prone to collapse under stress, failing to rebound and recover the contact force in time. Under stress, the brush head tends to disperse, leading to unstable contact and poor conductivity. The contact force between the brush head and the shaft cannot be adjusted, making it impossible to ensure a good conductive contact state. Summary of the Invention

[0005] This application provides a grounding carbon brush device for a large-diameter motor, which can make stable contact with the rotor spindle for electrical conduction, reduce shaft voltage and prevent shaft erosion, and is especially suitable for large-diameter high-speed motors.

[0006] This application provides a grounding carbon brush device for a large-diameter motor, comprising:

[0007] Rotor spindle;

[0008] A grounding ring is disposed on the outside of the rotor main shaft, and the grounding ring is provided with at least one mounting hole;

[0009] A carbon brush assembly is disposed between the outer ring of the rotor spindle and the inner ring of the grounding ring. The carbon brush assembly includes at least one carbon fiber bundle, with two ends of the carbon fiber bundle overlapping and connected in the same direction to form a fixing part, a bent part, and a connecting part connecting the bent part and the fixing part. The fixing part is fixed to the mounting hole and externally connected to the grounding terminal. At least a portion of the bent part is used to make contact with the rotor spindle for conductive connection, and the spindle current is introduced into the grounding terminal in sequence through the connecting part and the fixing part.

[0010] In some embodiments, the extending direction of the carbon fiber bundle intersects with the axial direction of the rotor spindle.

[0011] In some embodiments, the carbon fiber bundle is in contact with and connected to the rotor spindle along the radial direction of the rotor spindle.

[0012] In some embodiments, the center angle of the grounding ring ranges from 5° to 360°, and the grounding ring has a plurality of mounting holes; the carbon brush assembly includes a plurality of carbon fiber bundles spaced apart along the circumferential direction and / or axial direction of the grounding ring, at least a portion of the bent portion of the carbon fiber bundle abuts against the rotor spindle, and the fixing portion of the carbon fiber bundle is fixedly connected to the mounting holes.

[0013] In some embodiments, the carbon brush assembly includes multiple sets of carbon brush units spaced apart along the circumferential direction of the grounding ring, and each carbon brush unit includes multiple carbon fiber bundles spaced apart along the axial direction of the grounding ring.

[0014] In some embodiments, the groups of carbon brush units distributed along the circumferential direction are equally spaced.

[0015] In some embodiments, the bending portion includes a first bending portion, two second bending portions, and two third bending portions. The first bending portion is used to elastically abut against the rotor spindle, the third bending portion is used to connect the connecting portion, and the second bending portions are used to connect the first bending portion and the third bending portion.

[0016] In some embodiments, the opening width of the second bend is greater than the opening width of the first bend, and the opening width of the second bend is greater than the opening width of the third bend.

[0017] In some embodiments, the first bend portion is convex, and the first bend portion bends and protrudes toward one side of the rotor spindle.

[0018] In some embodiments, the mounting hole is provided with an internal thread; the large-diameter motor grounding carbon brush device further includes a fixing member and a locking member, the fixing member is provided with an inner hole and an external thread, the inner hole is sleeved on the fixing part, the fixing member is connected to the internal thread through the external thread, and the locking member is threadedly connected to the fixing member to fix the axial position of the fixing member.

[0019] The large-diameter motor grounding carbon brush device provided in this application uses carbon fiber bundles instead of traditional carbon fiber brush heads to achieve tangential contact between the carbon fibers and the rotor shaft in the circumferential direction, ensuring stable contact with the grounding device. The independent carbon brush units facilitate installation and maintenance, and have good manufacturability. This application uses carbon fiber bundle brush heads formed by bending several carbon fiber filaments as a whole, replacing traditional carbon blocks. This eliminates carbon dust generation and eliminates the need for collection devices or regular carbon dust cleaning. The integrally bent carbon fiber bundle brush head has low contact resistance with rotating parts, strong rebound ability under contact force, and stable and reliable contact. Furthermore, the carbon fiber bundle brush head in this application is located on the rotor shaft and uses radial contact conduction, allowing for free deformation in the radial direction and automatic adjustment of contact force during operation. In addition, this large-diameter motor grounding carbon brush device has few parts, a simple process, is easy to install, and convenient to maintain. It can be applied to various types of wind turbine generators, especially large-diameter high-linear-speed motors, and has a wide range of applications. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of a grounding carbon brush device for a large-diameter motor provided in some embodiments of this application;

[0022] Figure 2 A front view of a large-diameter motor grounding carbon brush device provided in some embodiments of this application;

[0023] Figure 3 A schematic diagram of the structure of a large-diameter motor grounding carbon brush device excluding the rotor spindle provided in some embodiments of this application;

[0024] Figure 4 This is a schematic diagram of the structure of the carbon fiber bundle, fixing member and locking member in the grounding carbon brush device for a large-diameter motor provided in some embodiments of this application.

[0025] The attached figures are labeled as follows:

[0026] 1-Rotor spindle; 2-Grounding ring; 3-Carbon fiber bundle; 4-Fixed component; 5-Locking component;

[0027] 31-Bending part; 32-Connecting part; 33-Fixing part; 311-First bending part; 312-Second bending part; 313-Third bending part;

[0028] A - Axis direction. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0030] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. The terms "first," "second," etc., are used to distinguish different objects, not to describe a particular order or hierarchy.

[0031] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0032] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0033] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0034] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0035] In this application, "multiple" means two or more (including two).

[0036] Please refer to Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the structure of a grounding carbon brush device for a large-diameter motor provided in some embodiments of this application; Figure 2 A front view of a large-diameter motor grounding carbon brush device provided in some embodiments of this application.

[0037] This application provides a grounding carbon brush device for a large-diameter motor, including a rotor main shaft 1, a grounding ring 2, and a carbon brush assembly. The rotor main shaft 1 is disposed on the inner ring of the grounding ring 2. The grounding ring 2 has an annular structure and is disposed on the outer side of the rotor main shaft 1. At least one mounting hole is provided on the grounding ring 2. The mounting hole can be a through hole that extends along the wall thickness direction of the grounding ring 2, or a countersunk hole that extends along the wall thickness direction of the grounding ring 2, so as to facilitate the installation of the carbon brush assembly.

[0038] The carbon brush assembly is disposed between the outer ring of the rotor spindle 1 and the inner ring of the grounding ring 2. The carbon brush assembly includes at least one carbon fiber bundle 3. The two ends of the carbon fiber bundle 3 are connected in the same direction to form a fixing part 33, a bending part 31 in the middle, and a connecting part 32 connecting the bending part 31 and the fixing part 33. The fixing part 33 is fixedly installed in the mounting hole and is connected to the grounding terminal. At least a part of the bending part 31 can make contact with the rotor spindle 1 and conduct electricity. It is connected to the grounding terminal through the connecting part 32 and the fixing part 33 in sequence, so as to conduct the spindle current to the ground, thereby avoiding damage to bearings and other components caused by the spindle current.

[0039] The carbon brush assembly may include one or more carbon fiber bundles 3, each composed of carbon fiber filaments. The two ends of the carbon fiber bundle 3 are overlapped and folded in the same direction, forming a fixed end that is fixed within the mounting hole of the grounding ring 2. In this way, the carbon fiber brush head can form a stable contact with the rotor spindle 1 to achieve conductivity. Grounding the carbon fiber brush head eliminates the potential difference between the inner and outer rings of the bearing, preventing electro-corrosion damage to bearings and other components, reducing shaft voltage, and achieving the function of preventing shaft electro-corrosion.

[0040] The large-diameter motor grounding carbon brush device provided in this application replaces the traditional carbon brush structure. Compared with the dispersed contact of the traditional carbon brush head and the point contact of the carbon fiber bundle, the carbon fiber bundle brush head structure formed by folding in this application forms an arc-shaped contact with the rotor main shaft 1 for conductivity. Compared with the point contact conductivity structure of the traditional brush head, the contact is smooth, the friction is small, the recovery stiffness is strong, and the brush head is not easy to fall over after the contact rotor shaft is subjected to force. It can rebound in time to restore the contact force, and the contact state is stable with strong conductivity.

[0041] In one specific embodiment, the extending direction of the carbon fiber bundle 3 intersects the axial direction of the rotor main shaft 1. The grounding ring 2 can be a ring structure. The extending direction of the carbon fiber bundle 3 can be along the radial direction of the rotor main shaft 1, or the extending direction of the carbon fiber bundle 3 can be approximately along the radial direction of the rotor main shaft 1. For example, the carbon fiber bundle 3 and the axial direction of the rotor main shaft 1 are distributed at a certain angle. This application does not limit this, but it is necessary to ensure that the bent part 31 of the carbon fiber bundle 3 is in contact with the rotor main shaft 1, and the fixing part 33 is fixedly connected to the grounding ring 2.

[0042] Optionally, the carbon fiber bundle 3 contacts and conducts with the rotor main shaft 1 in the radial direction, that is, the extension direction of the carbon fiber bundle 3 is perpendicular to the axial direction of the rotor main shaft 1, and the carbon fiber bundle 3 contacts and conducts with the rotor main shaft 1 in the radial direction. In this way, each carbon fiber bundle 3 forms radial conduction through elastic contact with the rotor main shaft 1, thereby enabling the carbon fiber bundle 3 to have a large deformation capacity in both the axial and radial directions. During operation, the contact state can be automatically adjusted, and a stable contact conductivity effect can be easily obtained.

[0043] In one specific embodiment, the carbon brush unit composed of carbon fiber bundles 3 can also be distributed in one-half, one-third, one-quarter, one-fifth, one-sixth, one-seventh, one-eighth, etc. regions corresponding to the rotor spindle 1. The grounding ring 2 has multiple mounting holes. The number of mounting holes for the carbon fiber brush assembly can be designed according to the magnitude of the motor shaft current. It should be ensured that each mounting hole on the grounding ring 2 corresponds to the installation of a carbon fiber bundle 3, and that the shaft current is quickly and timely discharged.

[0044] Correspondingly, the central angle of the grounding ring 2 ranges from 5° to 360°. The curvature and height of the grounding ring 2 can be designed according to the number and distribution area of ​​the carbon fiber bundles 3. The grounding ring 2 can be a complete circular structure or a partial circular structure, such as a half-circle, a third-circle, a quarter-circle, a fifth-circle, a sixth-circle, a seventh-circle, an eighth-circle, etc. The size of the grounding ring 2 can be various, and this application does not limit it.

[0045] refer to Figure 1In one optional embodiment, the grounding ring 2 has a circular structure. Correspondingly, the carbon brush assembly includes multiple carbon fiber bundles 3, which are spaced apart along the circumferential direction and / or axial direction of the grounding ring 2. At least a portion of the bent portion 31 of the carbon fiber bundle 3 abuts against the rotor main shaft 1, and the fixing portion 33 of the carbon fiber bundle 3 is fixedly connected to the mounting hole. The carbon brush assembly includes multiple sets of carbon brush units, each carbon brush unit being spaced apart along the circumferential direction of the grounding ring 2. Each carbon brush unit includes multiple carbon fiber bundles 3, which are spaced apart along the axial direction of the grounding ring 2.

[0046] The conductive structure, forming a circumferential and axial distribution around the outer ring of the rotor main shaft 1, allows current from various points on the rotor main shaft 1 to be introduced into the carbon brush assembly and then discharged. This achieves circumferential tangential contact between the carbon fibers and the rotor main shaft 1, ensuring stable contact with the grounding device, improving the stability and reliability of conductivity, and facilitating maintenance. It should be noted that the arrangement of the carbon fiber bundles 3 on the grounding ring 2 can be designed with different distribution numbers, spacings, and positions, etc., as required; this application does not impose any limitations on this.

[0047] Furthermore, the carbon brush units are evenly spaced along the circumferential direction, which makes the conductivity more uniform and the conductivity performance more stable and reliable.

[0048] refer to Figure 4 Regarding the structure of the bending portion 31, in one specific embodiment, it includes a first bending portion 311, two second bending portions 312, and two third bending portions 313. The first bending portion 311 is used to elastically abut against the rotor main shaft 1, the third bending portion 313 is used to connect the connecting portion 32, and the second bending portions 312 are used to connect the first bending portion 311 and the third bending portion 313.

[0049] The bending part 31 mainly contacts and conducts electricity with the rotor main shaft 1 through the first bending part 311, and the fixing part 33, the connecting part 32, the third bending part 313, the second bending part 312, the first bending part 311, another second bending part 312, another third bending part 313, another connecting part 32, and another fixing part 33 are sequentially connected to form a continuous carbon fiber bundle 3.

[0050] Optionally, the opening width of the second bend portion 312 is greater than the opening width of the first bend portion 311, and the opening width of the second bend portion 312 is greater than the opening width of the third bend portion 313. This forms a teardrop-shaped structure. The teardrop-shaped carbon fiber bundle 3 brush head has low contact resistance with the rotating part, and the carbon fiber grounding brush head forms a brush head with good elasticity and stable contact force. Unlike the dispersed independent brush head, it has strong rebound ability when subjected to contact force, and the contact state is stable and reliable. Its manufacturing process is simple and easy to install.

[0051] Continue to refer to Figure 4 The first bending portion 311 is convex, and the first bending portion 311 bends and protrudes towards the side of the rotor main shaft 1, thereby further improving the contact elasticity of the carbon fiber bundle 3, increasing the radial free deformation performance, reducing the contact area between the carbon fiber bundle 3 and the rotor main shaft 1, and improving the conductivity.

[0052] The carbon fiber bundle 3 in this application can be directly fixed in the mounting hole, or it can be fixed in the mounting hole of the grounding ring 2 via a connector. For example, the mounting hole is provided with an internal thread. The large-diameter motor grounding carbon brush device also includes a fixing member 4 and a locking member 5. The fixing member 4 is provided with an inner hole and an external thread. The inner hole is fitted onto the fixing part 33, ensuring a tight fit between the two. The fixing member 4 is connected to the internal thread of the grounding ring 2 via the external thread. The locking member 5 (e.g., a nut or bolt) is threadedly connected to the fixing member 4 to fix the axial position of the fixing member 4. Thus, by adjusting the distance between the nut and the threaded bolt, as well as the length of the carbon fiber, carbon fiber brush heads with different contact densities can be formed, thereby achieving the setting and adjustment of the initial contact stiffness.

[0053] It should be noted that the carbon fiber bundle in this application can be fixed integrally with the grounding ring or be detachable. The installation method of the carbon fiber brush assembly can be adjusted according to the actual use, and this application embodiment does not limit this. When a detachable type is used, the online installation and maintenance functions of adjusting the installation angle of the carbon fiber brush unit or replacing it individually can be realized without stopping the machine.

[0054] The above provides a detailed description of the large-diameter motor grounding carbon brush device provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are merely for the purpose of helping to understand the method and core ideas of this application. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from its principles, and these improvements and modifications also fall within the protection scope of this application.

Claims

1. A grounding carbon brush device for a large-diameter motor, characterized in that, include: Rotor spindle (1); A grounding ring (2) is disposed on the outside of the rotor main shaft (1), and the grounding ring (2) is provided with at least one mounting hole; A carbon brush assembly is disposed between the outer ring of the rotor spindle (1) and the inner ring of the grounding ring (2). The carbon brush assembly includes at least one carbon fiber bundle (3), the two ends of the carbon fiber bundle (3) are connected in the same direction to form a fixing part (33), a bending part (31) and a connecting part (32) connecting the bending part (31) and the fixing part (33). The fixing part (33) is fixed to the mounting hole and externally connected to the grounding terminal. At least a portion of the bending part (31) is used to make contact and conductive connection with the rotor spindle (1), and the spindle current is introduced into the grounding terminal through the connecting part (32) and the fixing part (33) in sequence.

2. The grounding carbon brush device for a large-diameter motor according to claim 1, characterized in that, The extension direction of the carbon fiber bundle (3) is intersected with the axial direction of the rotor main shaft (1).

3. The grounding carbon brush device for a large-diameter motor according to claim 2, characterized in that, The carbon fiber bundle (3) is in contact with the rotor main shaft (1) in the radial direction of the rotor main shaft (1).

4. The grounding carbon brush device for a large-diameter motor according to claim 1, characterized in that, The center angle of the grounding ring (2) ranges from 5° to 360°, and the grounding ring (2) has multiple mounting holes; The carbon brush assembly includes a plurality of carbon fiber bundles (3) spaced apart along the circumferential and / or axial direction of the grounding ring (2). At least a portion of the bent portion (31) of the carbon fiber bundle (3) abuts against the rotor spindle (1), and the fixing portion (33) of the carbon fiber bundle (3) is fixedly connected to the mounting hole.

5. The grounding carbon brush device for a large-diameter motor according to claim 4, characterized in that, The carbon brush assembly includes multiple sets of carbon brush units spaced apart along the circumferential direction of the grounding ring (2), and each carbon brush unit includes multiple carbon fiber bundles (3) spaced apart along the axial direction of the grounding ring (2).

6. The grounding carbon brush device for a large-diameter motor according to claim 5, characterized in that, The carbon brush units are distributed at equal intervals along the circumferential direction.

7. The grounding carbon brush device for a large-diameter motor according to any one of claims 1 to 6, characterized in that, The bending section (31) includes a first bending section (311), two second bending sections (312) and two third bending sections (313). The first bending section (311) is used to elastically abut against the rotor main shaft (1). The third bending section (313) is used to connect the connecting section (32). The second bending section (312) is used to connect the first bending section (311) and the third bending section (313).

8. The grounding carbon brush device for a large-diameter motor according to claim 7, characterized in that, The opening width of the second bending part (312) is greater than the opening width of the first bending part (311), and the opening width of the second bending part (312) is greater than the opening width of the third bending part (313).

9. The grounding carbon brush device for a large-diameter motor according to claim 8, characterized in that, The first bending portion (311) is convex and bends outward toward the rotor main shaft (1).

10. The grounding carbon brush device for a large-diameter motor according to claim 1, characterized in that, The mounting hole is provided with an internal thread; the large-diameter motor grounding carbon brush device also includes a fixing part (4) and a locking part (5). The fixing part (4) is provided with an inner hole and an external thread. The inner hole is sleeved on the fixing part (33). The fixing part (4) is connected to the internal thread through the external thread. The locking part (5) is threaded to the fixing part (4) to fix the axial position of the fixing part (4).

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