CN117989082A

CN117989082A - Lightning protection device and wind generating set

Info

Publication number: CN117989082A
Application number: CN202211350758.9A
Authority: CN
Inventors: 杨鹏飞
Original assignee: Jinfeng Technology Co ltd
Current assignee: Jinfeng Technology Co ltd
Priority date: 2022-10-31
Filing date: 2022-10-31
Publication date: 2024-05-07

Abstract

The present disclosure provides a lightning protection device and a wind generating set. The lightning protection device is used for a wind generating set, and the wind generating set comprises a main shaft bearing seat, a main shaft rotatably installed in the main shaft bearing seat and a main shaft bearing installed between the main shaft and the main shaft bearing seat. The lightning protection device comprises: a brush assembly including a bracket and a brush fixed to and insulated from the bracket; and a track portion having a circular ring shape, wherein one of the brush and the track portion is fixed with respect to the main shaft and is for connection with a lightning current lead-in wire, the other of the brush and the track portion is fixed with respect to the main shaft bearing housing and is for connection with a lightning current lead-out wire, and the brush and the track portion can be insulated from the main shaft bearing, wherein a brush head of the brush and the track portion correspond in position in an axial direction of the track portion and contact each other or form a discharge gap.

Description

Lightning protection device and wind generating set

Technical Field

The present disclosure relates to the field of wind power generation, and more particularly, to a lightning protection device and a wind generating set.

Background

With the increasing single-machine capacity of the wind generating set, the height of the hub and the diameter of the impeller are also increased, so that the wind generating set is easy to be struck by lightning. Typically, lightning protection systems are installed on wind power plants to direct lightning current from the impeller to the ground.

Typically, the bearings (e.g., pitch, main shaft, yaw, etc.) of the wind turbine are metal components and lightning current directed by the lightning protection system may flow through these bearings. When the wind generating set is struck by lightning, if lightning current flows through the metal bearing, the bearing is damaged by electric corrosion, lightning current breakdown and the like, and finally the safe operation of the bearing is seriously influenced. In addition, electrical corrosion and breakdown, etc., damage typically occurs inside the bearing or between two components that move relative to each other through the bearing, and thus such structural damage is not readily noticeable (e.g., burning the inner raceways and balls, etc.), and is typically only noticeable when the structural damage is exposed outside the bearing. Once the structural damage is exposed to the outside, the bearings have presented serious problems, which greatly increase the safety risk of the wind power plant.

The main shaft bearing is a core part of the wind generating set. Once the main shaft bearing is damaged, the main shaft bearing directly affects the normal operation of the wind generating set. If maintenance or replacement of the spindle bearings is required, a longer downtime is required. Furthermore, replacement of the main shaft bearings requires removal of the hub and blade assembly of the wind turbine and requires a large tonnage of hoisting machine for hoisting.

Disclosure of Invention

It is therefore an object of the present disclosure to provide a lightning protection device capable of forming an independent lightning current transfer path independent of the main shaft bearing.

It is also an object of the present disclosure to provide a lightning protection device that can ensure accuracy and reliability in a simple manner.

According to an aspect of the present disclosure, there is provided a lightning protection device for a wind power generation set comprising a main shaft bearing housing, a main shaft rotatably mounted in the main shaft bearing housing, and a main shaft bearing mounted between the main shaft and the main shaft bearing housing. The lightning protection device comprises: a brush assembly including a bracket and a brush fixed to and insulated from the bracket; and a track portion having a circular ring shape, wherein one of the brush and the track portion is fixed with respect to the main shaft and is for connection with a lightning current lead-in wire, the other of the brush and the track portion is fixed with respect to the main shaft bearing housing and is for connection with a lightning current lead-out wire, and the brush and the track portion can be insulated from the main shaft bearing, wherein a brush head of the brush and the track portion correspond in position in an axial direction of the track portion and contact each other or form a discharge gap.

Preferably, the brush assembly may further include a brush support arm extending toward the rail portion in a radial direction of the rail portion, one end of the brush support arm being connected to the bracket, the brush being connected to the other end of the brush support arm, wherein the brush support arm has elasticity and biases a brush head of the brush toward the rail portion.

Preferably, the bracket may include: a main body portion extending in a direction parallel to the axial direction, the brush support arm being connected to one side of the main body portion; the lightning protection device comprises a main body part, a first bending part and a lightning protection device, wherein the main body part is connected to the electric brush supporting arm, the first bending part bends towards one side of the main body part, which is connected to the electric brush supporting arm, from one end of the main body part, the lightning protection device further comprises a first wiring part, the first wiring part is fixed to the first bending part and is insulated from the bracket, and a lead wire of the electric brush is connected to the first wiring part.

Preferably, the lightning protection device may further include a first insulation part disposed between the first connection part and the first bending part, and both ends of the first insulation part are connected with the first connection part and the first bending part, respectively.

Preferably, the bracket may be an insulating member, the lightning protection device further includes a first connection part fixed to the bracket, and the lead wire of the brush is connected to the first connection part.

Preferably, the lightning protection device may further include: a second wiring portion connected to one side of the track portion in the axial direction; and the second insulating part is connected to the other axial side of the track part.

Preferably, the rail portion may include a circular ring portion, and first and second protruding portions extending outward and inward from the circular ring portion in a radial direction, respectively, wherein the second wiring portion is fixed to the first protruding portion, and the second protruding portion corresponds in position to the second insulating portion in the axial direction and is used for mounting the rail portion to the wind power generation set.

Preferably, the track portion may comprise a plurality of arc segments, two adjacent arc segments of the plurality of arc segments being spliced together by an oblique seam, wherein the first protrusion and the second protrusion are formed at an oblique seam splice, the lightning protection device further comprising a backing plate, the backing plate being located between the track portion and the second insulation portion at the oblique seam splice.

Preferably, the track portion may comprise a plurality of arcuate segments, adjacent two of the plurality of arcuate segments being spliced together by a diagonal seam.

Preferably, the brush may be a constant voltage brush.

According to another aspect of the present disclosure, a wind power plant is provided, comprising a lightning protection device as described above.

Preferably, the main shaft bearing may be a rolling bearing and may include a bearing fixed ring coupled to the main shaft bearing housing and a bearing movable ring coupled to the main shaft, the wind power generation set further including a first end cover positioned axially outward of the bearing movable ring and fixed with respect to the bearing movable ring and the main shaft, and a second end cover positioned axially outward of the bearing fixed ring and fixed with respect to the bearing fixed ring and the main shaft bearing housing, the one of the brush and the rail portion being fixed with respect to the first end cover, the other of the brush and the rail portion being fixed with respect to the second end cover.

Preferably, the main shaft bearing may be a sliding bearing and may include a bushing provided between the main shaft and the main shaft bearing housing, the wind power generation set further including a first end cap located axially outward of the main shaft and fixed with respect to the main shaft, and a second end cap located axially outward of the main shaft bearing housing and fixed with respect to the main shaft bearing housing, the one of the brush and the rail portion being fixed with respect to the first end cap, the other of the brush and the rail portion being fixed with respect to the second end cap.

Preferably, the bracket may be fixed to the first end cap and the lead wire of the brush is connected to the lightning current lead-in wire, and the rail portion may be fixed to the second end cap and connected to the lightning current lead-out wire.

Preferably, the rail portion may be fixed to the first end cap and connected to the lightning current lead-in wire, the bracket may be fixed to the second end cap and the lead-out wire of the brush is connected to the lightning current lead-out wire.

By adopting the lightning protection device disclosed by the invention, an independent lightning current transmission path independent of the main shaft bearing can be formed, and the main shaft bearing is prevented from being broken down by lightning current. In addition, the lightning protection device disclosed by the invention can ensure the coaxiality between the electric brush and the track part at the moment depending on the coaxiality between the main shaft bearing seat and the main shaft, so that the precision and the reliability of the lightning protection device are higher. In addition, the main shaft and the main shaft bearing seat can provide stable support for the electric brush and the track part, and the power of the main shaft can ensure the stability of the large-diameter running track motion of the electric brush relative to the track part.

Drawings

The foregoing and other objects, features, and advantages of the disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of a structure in which a lightning protection device according to an embodiment of the present disclosure is mounted on a wind turbine;

fig. 2 is an enlarged view of the region I in fig. 1;

FIG. 3 is a partial cross-sectional view of a structure in which a lightning protection device according to an embodiment of the present disclosure is mounted on a wind turbine;

FIG. 4 is a plan view of a track portion of a lightning protection device according to an embodiment of the disclosure;

Fig. 5 and 6 are perspective views of the second insulating member and the pad, respectively;

fig. 7 is a perspective view showing a structure in which the first wire connecting portion is mounted on the brush assembly;

fig. 8 and 9 are perspective views of the bracket and the first insulating portion, respectively.

Detailed Description

Embodiments in accordance with the present disclosure will now be described in detail with reference to the drawings, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

The specific structure of the lightning protection device according to the present disclosure and the installation state on the wind power generation set will be described below with reference to fig. 1 to 9.

The lightning protection device according to the present disclosure may be used in a wind power generator set. As shown in fig. 1 and 3, the wind power generation set includes a main shaft bearing housing 71, a main shaft 72 rotatably installed in the main shaft bearing housing 71, and a main shaft bearing 73 installed between the main shaft 72 and the main shaft bearing housing 71. Spindle 72 is fixed to a fan hub (not shown) and receives power from the fan hub for generating electricity.

Referring to fig. 1 to 3, a lightning protection device according to an embodiment of the present disclosure includes: a brush assembly 10 including a holder 11 and a brush 12, the brush 12 being fixed to the holder 11 and insulated from the holder 11; the track portion 20 is in a circular ring shape, wherein one of the brush 12 and the track portion 20 is fixed with respect to the main shaft 72 and is used for connection with the lightning current lead-in wire 61, the other of the brush 12 and the track portion 20 is fixed with respect to the main shaft bearing housing 71 and is used for connection with the lightning current lead-out wire 62, and the brush 12 and the track portion 20 can be insulated from the main shaft bearing 73, wherein the brush head 121 of the brush 12 and the track portion 20 correspond in position in the axial direction of the track portion 20 and contact each other or form a discharge gap. During the rotation of spindle 72, spindle 72 rotates one of brush 12 and track portion 20 relative to the other, and ensures that brush 12 is always in contact with track portion 20 or forms a discharge gap, thereby ensuring a continuous lightning current transmission path.

When a wind turbine blade of a wind turbine generator is struck by lightning, a lightning current is transferred from the lightning current lead-in wire 61 to one of the brush 12 and the track portion 20, then between the brush 12 and the track portion 20, and finally to the lightning current lead-out wire 62 through the other of the brush 12 and the track portion 20, thereby forming a lightning current transfer path. Since the brush 12 and the track portion 20 can be insulated from the main shaft bearing 73, the lightning current path described above does not pass through the main shaft bearing 73, i.e., the main shaft bearing 73 does not participate in lightning current transmission, and thus the lightning current path described above is an independent path independent of the main shaft bearing. In fig. 3 of the present disclosure, the main shaft bearing 73 is illustrated as a rolling bearing, in which case the lightning current path described above can prevent lightning current breakdown from occurring between any two of the bearing moving ring, the bearing fixed ring, and the rolling body of the rolling bearing (such lightning current breakdown would cause structural damage to the main shaft bearing), thereby avoiding damage to the main shaft bearing by lightning current. However, the present disclosure is not limited thereto, and the main shaft bearing 73 may also be a sliding bearing, in which case the lightning current path described above can prevent lightning current breakdown from occurring between the main shaft bearing housing 71 and the main shaft 72.

In addition, through installing the brush and the track portion of lightning protection device on wind generating set's main shaft and main shaft bearing frame, can rely on the axiality between main shaft bearing frame and the main shaft to ensure the axiality between brush and the track portion constantly, therefore the lightning protection device according to this disclosure simple structure to installation accuracy is easy control. Further, the rail portion and the brush are fixed to the main shaft and the main shaft bearing housing (instead of the less rigid member, such as the nacelle housing, etc.), so it is possible to further secure the coaxiality between the brush and the rail portion and to provide stable support for the rail portion and the brush to prevent poor contact of the brush or the rail portion due to displacement or deformation of the two. In addition, the brush or the rail portion is rotated by the power of the spindle, which can ensure the stability of the large-diameter running track motion of the brush with respect to the rail portion.

In the present disclosure, the lightning current lead-in wire 61 of the lightning protection device of the present disclosure is connected to a lightning down-conductor from the fan hub. Specifically, the lightning down conductor from the fan hub is threaded from within the fan hub to the axially outer side of the spindle 72 through the fan hub and spindle 72 mounting plane opening as a passageway, and then connected to the lightning current lead-in conductor 61 of the lightning protection device. The track portion 20 and the brush assembly 10 are mounted on the side of the main shaft 72 and the main shaft bearing housing 71 facing the fan hub to approach the lightning down conductor and shorten the cable distance between the lightning down conductor and the lightning current conductor. Preferably, brush assembly 10 and track portion 20 are mounted adjacent to the end faces of spindle 72 and spindle bearing housing 71 facing the fan hub.

Further, in fig. 1,2, 3, 4 and 7 of the present disclosure, it is shown that the bracket 11 is fixed to the main shaft 72 and the brush 12 is connected with the lightning current lead-in wire 61, and the track portion 20 is fixed to the main shaft bearing housing 71 and connected with the lightning current lead-out wire 62. In this case, the lightning current from the lightning down conductor at the fan hub is transmitted to the brush 12 via the lightning current lead-in wire 61, and then to the rail portion 20 via the brush head 121 of the brush 12, and finally the lightning current is led out of the position of the main shaft bearing 73 via the lightning current lead-out wire 62. At this time, since the brush 12 is fixed to the main shaft 72 by the bracket 11, the brush 12 rotates in synchronization with the fan hub, so that the lightning down conductor from the fan hub rotates in synchronization with the lightning current lead-in wire 61 without twisting. In addition, lightning current is transferred from the brush 12 to the annular track portion 20 in a point-to-face transfer manner, so that transmission of high-frequency current is facilitated, a safety factor of lightning current transmission can be improved, and occurrence of single-point concentrated discharge and flashover can be avoided.

However, the present disclosure is not limited thereto, and the mounting positions of the brush assembly 10 and the rail portion 20 on the wind power generation set may be interchanged. Specifically, the track portion 20 may be fixed to the main shaft 72 and connected to the lightning current lead-in wire 61, the bracket 11 may be fixed to the main shaft bearing housing 71 and the brush 12 connected to the lightning current lead-out wire 62. In this case, the lightning current from the lightning down conductor at the fan hub is transferred to the track portion 20 via the lightning current lead-in wire and then to the brush 12, and finally the lightning current is led out of the position of the main shaft bearing 73 via the lightning current lead-out wire 62. The lightning down conductor and the lightning current lead-in conductor from the fan hub can synchronously rotate, and the cable twisting phenomenon can not occur.

In the present disclosure, since it is considered that the lightning down conductor from the fan hub rotates together with the fan hub, in order to prevent the occurrence of twisting, the lightning down conductor at the fan hub is connected with the track portion 20 or the brush 12 fixed with respect to the main shaft 72.

Further, as shown in fig. 2 and 3, the brush assembly 10 may further include a brush support arm 13, the brush support arm 13 extending toward the track portion 20 along a radial direction of the track portion 20, one end of the brush support arm 13 being connected to the bracket 11, and the brush 12 being connected to the other end of the brush support arm 13. Further, the brush support arm 13 has elasticity and biases the brush head 121 of the brush 12 toward the rail portion 20 so that the brush head 121 of the brush 12 always contacts the rail portion 20 or forms a discharge gap. The brush support arm 13 may be integrally formed of an elastic material. Further, the brush support arm 13 may insulate the brush 12 from the bracket 11, and thus the brush support arm 13 may be formed of an elastic insulating material. Alternatively, the brush support arm 13 may be formed of a metal elastic material, and fixed to the bracket 11 by an insulating member.

Further, as shown in fig. 2 and 8, the bracket 11 may include: a main body portion 111 extending in a direction parallel to an axial direction of the rail portion 20, the brush support arm 13 being connected to one side of the main body portion 111; the first bending portion 112 is bent from one end of the main body portion 111 toward the side of the main body portion 111 connected to the brush support arm 13. The lightning protection device may further include a first connection part 31, the first connection part 31 being fixed to the first bent part 112 and insulated from the bracket 11, and the lead 122 of the brush 12 being connected to the first connection part 31 to enable transfer of lightning current between the first connection part 31 and the brush 12. By bending the first bending portion 112 toward one side of the brush support arm 13 and fixing the first wiring portion 31 to the first bending portion 112, the size of the brush assembly can be reduced, thereby saving the installation space of the lightning protection device.

Further, the bracket 11 may include a second bent portion 113 and an intermediate protrusion 114 in addition to the main body portion 111 and the first bent portion 112. The second bending portion 113 is bent from the other end of the main body portion 111 in the same direction as the first bending portion 112, and is used to fix the bracket 11 to the wind power generation set so that the brush 12 is fixed with respect to the main shaft 72 or the main shaft bearing housing 71. The intermediate protrusion 114 is bent from a position between both ends of the main body portion 111 in the same direction as the first and second bent portions 112 and 113, and the brush support arm 13 may be fixed to the intermediate protrusion 114.

As shown in fig. 2, 7 and 9, the lightning protection device may further include a first insulation part 41, the first insulation part 41 being disposed between the first connection part 31 and the first bending part 112, and both ends of the first insulation part 41 being connected with the first connection part 31 and the first bending part 112, respectively, thereby insulating and fixing the first connection part 31 with the bracket 11. Specifically, as shown in fig. 9, the first insulating portion 41 has a rectangular plate shape, and has: a first mounting hole 411 formed at one end of the first insulating portion 41 for fixing the first insulating portion 41 to the first bent portion 112 of the bracket 11: a second mounting hole 412 formed at the other end of the first insulating portion 41 for fixing the first wiring portion 31 to the first insulating portion 41. As shown in fig. 2, the first wiring portion 31 has a radial portion extending in the radial direction and an axial portion extending in the axial direction. The radial portion of the first wiring portion 31 is formed with a hole corresponding to the second mounting hole 412, and is fixed with the first insulating portion 41 by a fastener. The axial portion of the first wiring portion 31 is for connection with the lightning current lead-in wire 61.

However, the present disclosure is not limited thereto, and insulation between the first wiring portion 31 and the bracket 11 may be achieved by other means. For example, the holder 11 may be an insulating member, the first wiring portion 31 is directly fixed to the holder 11, and the lead wire 122 of the brush 12 is connected to the first wiring portion 31.

As shown in fig. 2,4 and 5, the lightning protection device may further include: a second wiring portion 32 connected to one side of the track portion 20 in the axial direction; the second insulating portion 42 is connected to the other axial side of the rail portion 20, thereby insulating the rail portion 20 from the spindle 72 or the spindle bearing housing 71. Specifically, as shown in fig. 2, the second wiring portion 32 extends from the rail portion 20 away from the rail portion 20 in the axial direction, and is connected to the lightning current outgoing line 62.

Further, as shown in fig. 2 and 4, the rail portion 20 includes a circular ring portion 21, and a first protruding portion 22 and a second protruding portion 23 extending outward and inward from the circular ring portion 21 in the radial direction, respectively, wherein the second wiring portion 32 is fixed to the first protruding portion 22, and the second protruding portion 23 corresponds in position to the second insulating portion 42 in the axial direction and is used for mounting the rail portion 20 to the spindle 72 or the spindle bearing housing 71. That is, the spindle or the spindle bearing housing provides support for the rail portion in the axial direction, which enables the position of the rail portion to be more stable. Even if the brush applies pressure to the rail portion and rubs and slides on the rail portion, stable support can be provided for the brush without worrying about deformation of the rail portion due to the pressure of the brush.

Specifically, as shown in fig. 2 and 5, a recess whose opening faces the rail portion is formed in the second insulating portion 42. The second insulating portion 42 has: a first hole 421 formed at one end of the second insulating part 42 for fixing the second protruding part 23 and the second insulating part 42 together; the second aperture 422 is provided such that,

Formed in the recess for fixing the second insulating portion 42 to the spindle 72 or the spindle bearing housing 71. The recess in second insulator 42 may accommodate a fastener for securing second insulator 42 to spindle 72 or spindle carrier 71, thus insulating rail portion 20 from spindle 72 or spindle carrier 71 even if the fastener is metallic.

As shown in fig. 4, the track portion 20 may include a plurality of arcuate segments, adjacent two of which are spliced together to form the annular track portion 20. The track part is formed by splicing the arc sections, the arc sections can be processed by using the plates with smaller sizes and then spliced together, so that the processing cost can be saved, and meanwhile, the transportation is convenient. In addition, two adjacent arc segments can be spliced together through the oblique seam, so that when the electric brush 12 contacts the track portion 20 and moves relative to the track portion 20, the electric brush can be ensured to slide smoothly relative to the track portion, and abrasion and impact of the track portion to the electric brush are reduced. In contrast, in the case where two adjacent arc segments are spliced together by straight slits, the brush is blocked by the straight slits when sliding with respect to the rail portion.

Further, the first protrusion 22 and the second protrusion 23 may be formed at the oblique seam splice. As shown in fig. 2 and 6, the lightning protection device may further include a backing plate 50, and the backing plate 50 is located between the track portion 20 and the second insulating portion 42 at the splice of the oblique seam to enhance the structural strength of the splice of the oblique seam. Specifically, the pad 50 has one end formed with a shape corresponding to the second protruding portion 23 and the other end formed in a plate shape. Further, the shim plate 50 may be formed of a conductive material (e.g., a conductive metal) so that even if a gap exists between two adjacent arc segments to cause a break in lightning current to be formed along the circumferential direction of the track portion, the two adjacent arc segments can be connected together by the shim plate to prevent the lightning flow path of the circumferential direction of the track portion from being broken.

In addition, as shown in fig. 4, the first protrusion 22 and the second protrusion 23 may also be formed at positions of the rail portion 20 where no oblique seam is spliced, according to the need of installing the rail portion 20.

In addition, the second wire connection portion 32 may be connected at a position vertically below the track portion 20 in order to bring the lightning current outgoing wire 62 close to the lightning current transfer means at the yaw bearing. However, the present disclosure is not limited thereto, and in the case where the track portion 20 is connected to the lightning current lead-in wire 61, the second wiring portion 32 may be provided at any position on the track portion as long as it can be connected to the lightning down-conductor from the fan hub.

In an embodiment of the present disclosure, the brush 12 may be a constant voltage brush. The constant voltage brush ensures constant contact pressure between the brush head 121 and the arc surface by a constant voltage spring. However, the present disclosure is not limited thereto, and the brush 12 may be replaced with other conductive members capable of transmitting lightning current to the track portion 20, such as a conductive cable or the like. Or in addition to the lightning current transmitted through the brush 12, the lightning current may be transmitted between the first wiring portion 31 and the track portion 20 by means of a tip discharge.

In addition, the brush 12 is detachably mounted to the bracket 11 or the brush support arm 13, so that the brush can be replaced alone without disassembling the entire brush assembly, which can facilitate replacement of the brush without affecting the integrity of the overall structure and the hidden danger of damage to components caused by frequent disassembly.

The present disclosure also provides a wind power generation set comprising a lightning protection device as described above. In the wind turbine generator system of the present disclosure, as described above, the main shaft bearing 73 may be a rolling bearing or a sliding bearing.

Fig. 3 illustrates a main shaft bearing 73 as an example of a rolling bearing. Specifically, the spindle bearing 73 includes a bearing fixed ring coupled to the spindle bearing housing 71 and a bearing movable ring coupled to the spindle 72. The wind power generator set may further comprise a first end cap 74 located axially outward of the bearing rotor and fixed relative to the bearing rotor and main shaft 72, and a second end cap 75 located axially outward of the bearing stator and fixed relative to the bearing stator and main shaft bearing housing 71.

In the case of a sliding bearing, the spindle bearing comprises a bearing shell arranged between the spindle and the spindle bearing support. The wind power generation set may further include a first end cap located axially outward of the main shaft and fixed with respect to the main shaft, and a second end cap located axially outward of the main shaft bearing housing and fixed with respect to the main shaft bearing housing.

Whether the main shaft bearing is a rolling bearing or a sliding bearing, the lightning protection device can have the following states when being installed on the wind generating set: one of the brush and the track portion is fixed relative to the spindle relative to the first end cap and the other of the brush and the track portion (fixed relative to the spindle bearing housing) is fixed relative to the second end cap.

The first end cover 74 and the second end cover 75 are located on the side facing the fan hub near the main shaft 72 and the main shaft bearing seat 71, so that the brushes 12 and the track portion 20 are fixed on the first end cover 74 and the second end cover 75, compared with the case that the lightning protection device is fixed in the middle of the inside of the main shaft or on the side far away from the fan hub, so that the lightning protection device is more close to the lightning protection down conductor from the fan hub and is far away from the cable in the center of the main shaft, and electromagnetic interference is prevented from being generated.

Specifically, as shown in fig. 2 and 3, the bracket 11 is fixed to the first end cap 74 such that the brush 12 is fixed relative to the first end cap 74 and the main shaft 72, and the lead 122 of the brush 12 is connected to the lightning current lead-in wire 61. The rail portion 20 is fixed to the second end cap 75 such that the rail portion 20 is fixed with respect to the main shaft bearing housing 71, and the rail portion 20 is connected with the lightning current lead-out wire 62. In this way, the lightning current can flow from the lightning current lead-in wire 61 into the brush 12, then transferred to the track portion 20 and flow out through the lightning current lead-out wire 62.

Further, the fixed positions of the bracket 11 and the rail portion 20 with respect to the first end cap 74 and the second end cap 75 shown in fig. 3 are interchangeable. In particular, the rail portion is fixed to the first end cap such that the rail portion is fixed relative to the main shaft and the rail portion is connected with the lightning current lead-in. The bracket is fixed to the second end cap such that the brush is fixed relative to the second end cap and the main shaft bearing housing, and the leads of the brush are connected with the lightning current lead-out wires. In this way, the lightning current can flow from the lightning current lead-in wire into the track portion, then be transferred to the brush and flow out through the lightning current lead-out wire.

In addition, although the bracket 11 and the rail portion 20 are described above as being fixed to the first and second end caps 74 and 75, the present disclosure is not limited thereto, and the bracket 11 and the rail portion 20 are fixed to other members fixed with respect to the main shaft 72 and the main shaft bearing housing 71.

Preferably, the arrangement of the lightning current transmission paths in the wind turbine generator system is as smooth as possible away from electromagnetic environment sensitive components such as signal cables or sensors, and adverse effects on signal transmission and normal operation of electrical components caused by large current inrush in the process of lightning strike of the wind turbine generator system can be reduced to the greatest extent.

Preferably, in the present disclosure, the lightning current path from the fan blade to the ground does not pass through other bearings of the wind power plant (e.g. pitch bearings and yaw bearings), which makes the lightning current flow to the ground completely independent of all bearings of the wind power plant, ensuring a stable operation of all bearings of the wind power plant.

By adopting the lightning protection device disclosed by the invention, an independent lightning current transmission path independent of the main shaft bearing can be formed, and damage of lightning current to the main shaft bearing is avoided, so that the safety and the operation stability of the wind generating set are ensured. In addition, the lightning protection device disclosed by the invention can ensure the coaxiality between the electric brush and the track part at the moment depending on the coaxiality between the main shaft bearing seat and the main shaft, so that the installation precision of the lightning protection device is easy to control, and the operation precision and reliability can be ensured. In addition, the main shaft and the main shaft bearing seat can provide stable support for the brush and the track part, so as to prevent poor contact of the brush and the track part caused by displacement or deformation of the brush or the track part. In addition, the brush or the rail portion is rotated by the power of the spindle, which can ensure the stability of the large-diameter running track motion of the brush with respect to the rail portion.

Although a few embodiments of the present disclosure have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.

Claims

1. A lightning protection device for a wind power generation set comprising a main shaft bearing housing (71), a main shaft (72) rotatably mounted in the main shaft bearing housing (71), and a main shaft bearing (73) mounted between the main shaft (72) and the main shaft bearing housing (71), characterized in that the lightning protection device comprises:

a brush assembly (10) comprising a holder (11) and a brush (12), the brush (12) being fixed to the holder (11) and insulated from the holder (11);

a track part (20) which is in a circular ring shape,

Wherein one of the brush (12) and the track portion (20) is fixed with respect to the main shaft (72) and is adapted to be connected with a lightning current lead-in wire (61), the other of the brush (12) and the track portion (20) is fixed with respect to the main shaft bearing housing (71) and is adapted to be connected with a lightning current lead-out wire (62), and the brush (12) and the track portion (20) are adapted to be insulated from the main shaft bearing (73),

Wherein the brush head (121) of the brush (12) and the track portion (20) are in position correspondence in the axial direction of the track portion (20) and contact each other or form a discharge gap.

2. The lightning protection device according to claim 1, wherein the brush assembly (10) further comprises a brush support arm (13), the brush support arm (13) extending in a radial direction of the track portion (20) towards the track portion (20), one end of the brush support arm (13) being connected to the bracket (11), the brush (12) being connected to the other end of the brush support arm (13), wherein the brush support arm (13) has elasticity and biases a brush head (121) of the brush (12) towards the track portion (20).

3. The lightning protection device according to claim 2, characterized in that the bracket (11) comprises:

A main body portion (111) extending in a direction parallel to the axial direction, the brush support arm (13) being connected to one side of the main body portion (111);

A first bending portion (112) which is bent from one end of the main body portion (111) toward a side of the main body portion (111) connected to the brush support arm (13),

Wherein, lightning protection device still includes first wiring portion (31), first wiring portion (31) are fixed to on first kink (112) and with support (11) are insulating, lead wire (122) of brush (12) are connected to on first wiring portion (31).

4. The lightning protection device according to claim 3, further comprising a first insulating portion (41), wherein the first insulating portion (41) is disposed between the first wiring portion (31) and the first bending portion (112), and both ends of the first insulating portion (41) are connected to the first wiring portion (31) and the first bending portion (112), respectively.

5. The lightning protection device according to claim 1, characterized in that the bracket (11) is an insulating member, the lightning protection device further comprising a first wiring portion (31), the first wiring portion (31) being fixed on the bracket (11), the lead (122) of the brush (12) being connected to the first wiring portion.

6. The lightning protection device of claim 1, further comprising:

a second connection part (32) connected to one side of the track part (20) in the axial direction;

and a second insulating portion (42) connected to the other axial side of the rail portion (20).

7. The lightning protection device according to claim 6, characterized in that the rail portion (20) comprises a ring portion (21) and a first projection (22) and a second projection (23) extending outwardly and inwardly from the ring portion (21) in a radial direction, respectively, wherein the second wiring portion (32) is fixed to the first projection (22), the second projection (23) corresponding in position to the second insulation portion (42) in the axial direction and being adapted for mounting the rail portion (20) to the wind power generator set.

8. The lightning protection device according to claim 7, wherein the track portion (20) comprises a plurality of arcuate segments, adjacent two arcuate segments of the plurality of arcuate segments being joined together by a diagonal seam, wherein the first protrusion (22) and the second protrusion (23) are formed at a diagonal seam joint, the lightning protection device further comprising a shim plate (50), the shim plate (50) being located between the track portion (20) and the second insulation portion (42) at the diagonal seam joint.

9. The lightning protection device according to claim 1, wherein the track portion (20) comprises a plurality of arcuate segments, adjacent two of the plurality of arcuate segments being spliced together by a diagonal seam.

10. The lightning protection device according to claim 1, characterized in that the brush (12) is a constant voltage brush.

11. A wind power plant, characterized in that it comprises a lightning protection device according to any of claims 1 to 10.

12. Wind power plant according to claim 11, characterized in that the main shaft bearing (73) is a rolling bearing and comprises a bearing stator in combination with the main shaft bearing housing (71) and a bearing rotor in combination with the main shaft (72),

The wind power generator set further comprises a first end cover (74) which is positioned at the axial outer side of the bearing moving coil and is fixed relative to the bearing moving coil and the main shaft (72), and a second end cover (75) which is positioned at the axial outer side of the bearing fixed coil and is fixed relative to the bearing fixed coil and the main shaft bearing seat (71),

The one of the brush (12) and the track portion (20) is fixed relative to the first end cap (74), and the other of the brush (12) and the track portion (20) is fixed relative to the second end cap (75).

13. Wind power plant according to claim 11, characterized in that the main shaft bearing (73) is a plain bearing and comprises a bushing arranged between the main shaft (72) and the main shaft bearing housing (71),

The wind generating set further comprises a first end cover which is positioned at the axial outer side of the main shaft (72) and is fixed relative to the main shaft (72), and a second end cover which is positioned at the axial outer side of the main shaft bearing seat (71) and is fixed relative to the main shaft bearing seat (71),

The one of the brush (12) and the track portion (20) is fixed relative to the first end cap, and the other of the brush (12) and the track portion (20) is fixed relative to the second end cap.

14. Wind power unit according to claim 12 or13, characterized in that the bracket (11) is fixed to the first end cap and the leads (122) of the brushes (12) are connected with the lightning current lead-in wires (61), and the track portion (20) is fixed to the second end cap and connected with the lightning current lead-out wires (62).

15. Wind park according to claim 12 or 13, wherein the track portion (20) is fixed to the first end cap and connected with the lightning current lead-in wire (61), the bracket (11) is fixed to the second end cap and the lead-out wire (62) of the brush (12) is connected with the lightning current lead-out wire (122).