Connecting structure and connecting method of wind power blade body branch lightning arrester

Abstract

A connecting structure of a branch lightning arrester of a wind power blade body comprises the branch lightning arrester embedded in the surface of the blade body, a first conductor extending in the length direction of the blade body and attached to the surface of the blade body and a second conductor attached to the surface of the blade body and overlapped with the first conductor in a crossed mode, and the first conductor and the second conductor are provided with overlapping areas. The overlapping area covers the branch lightning arresters, and the first conductor, the second conductor and the branch lightning arresters are electrically connected. According to the branch lightning arrester connecting structure and the branch lightning arrester connecting method, the lightning arresting area of the blade body lightning arrester is increased, meanwhile, the structural reliability of the blade body lightning arrester is improved, the lightning current guiding effect is enhanced, and damage of the lightning current to a lightning protection mechanism is reduced.

Description

Technical Field

[0001] The invention relates to the field of lightning protection for wind power equipment, and in particular to a connection structure and a connection method for a wind power blade body branch lightning arrester. Background Art

[0002] The lightning protection device of wind turbine blades is mainly used for lightning protection of wind turbine blades. When lightning occurs near wind turbine blades, the lightning protection device can prevent lightning from directly penetrating the wind turbine blades. Instead, it intercepts lightning through the corresponding lightning receptors, ensuring that lightning strikes occur on the lightning receptors of the lightning protection device, and transmits lightning current to the root of the wind turbine blades through its own current downconductor system, and then transfers it to the ground through the tower, thereby reducing the damage of lightning strikes to wind turbine blades, reducing direct and indirect economic losses caused by lightning damage, and ensuring long-term, continuous and effective power generation supply of wind turbines. At present, the widely used lightning protection system for wind turbine blades mainly captures lightning current through lightning receptors set on the surface of the blades, and then transfers it to the downconductor inside the blades for current conduction. The lightning receptors on the surface of the blades include blade tip lightning receptors and blade body lightning receptors, both of which are used to divert current and prevent lightning from directly damaging the blades. However, the blade body lightning receptor is only considered to be simply connected to the downconductor, and the lightning receptor layout and structural reliability of the blade body lightning receptor have not been fully explored and avoided.

[0003] Through searching, technical documents of wind turbine blade lightning protection system have been disclosed in the prior art. For example, the utility model authorization announcement document with the publication number of "CN215486353U" and the name of "A wind turbine blade structure with lightning protection". A wind turbine blade structure with lightning protection is disclosed, including a group of blades, the blades include a skeleton and an outer shell, the skeleton includes a core rod parallel to the long axis of the blade, a group of side rods are evenly distributed on the core rod, the side rods are perpendicular to the core rod, and the side rods are radially distributed with the core rod as the center, the outer shell includes an inner layer, a skin is provided on the outer surface of the inner layer, and a group of conductive sheets are also provided on the outer surface of the inner layer, the conductive sheets are located at the ends of the side rods, and conductors are provided at the center of the side rods and the core rods. The conductors on the core rods are connected to the conductors on the side rods, and the conductive sheets are connected to the conductors on the side rods. The technical solution disclosed in this comparative document takes into account the lightning protection effect and strengthens the structural strength of the blades, but its guide strips are not connected to the branch lightning receptors, and the lightning receptor area of ​​each branch lightning receptor is limited, and the lightning protection effect is not good.

[0004] For example, the invention patent publication document with the publication number "CN108425811A" and the name "A Lightning Protection System for Wind Turbine Blades" discloses a lightning protection system for wind turbine blades, which is used to enhance the lightning protection performance of wind turbine blades. The method of the embodiment of the present invention includes: a blade, a lightning rod, and a grounding device, and the system also includes: a blade tip guide bar, a leading edge guide bar, and a trailing edge guide bar; the blade tip guide bar, the leading edge guide bar, and the trailing edge guide bar are respectively fixed on the blade and electrically connected to the lightning rod; the lightning rod is electrically connected to the grounding device through a preset down conductor. In the technical solution disclosed in the comparative document, the blade body lightning rod is only connected to the branch line of the down conductor, and the drainage capacity is weak and the lightning area is limited.

[0005] For example, the invention patent publication document with the publication number "CN117329089A" and the name "A lightning protection mechanism and protection method for a wind blade" discloses a lightning protection mechanism and protection method for a wind blade, including a lightning receptor installed on the blade and a lower conductor installed inside the blade, the lightning receptor is conductively connected to the lower conductor; and also includes a conductive component installed on the outer surface of the blade, the conductive component is used to guide the lightning current to the lightning receptor. In the technical solution disclosed in the comparative document, the blade body lightning receptor is exposed on the blade, the lightning receptor layout problem is not fully considered, and the reliability is not strong.

[0006] Therefore, it is of great significance to propose a connection structure and a connection method for a wind turbine blade body branch lightning arrester with a larger lightning arrester area, stronger drainage capability and higher structural reliability in the art. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention provides a connection structure of a branch lightning rod of a wind turbine blade, comprising a branch lightning rod embedded in the surface of the blade, comprising a first conductor extending along the length direction of the blade and attached to the surface of the blade, and also comprising a second conductor attached to the surface of the blade and cross-stacked with the first conductor, wherein the first conductor and the second conductor have an overlapping area, wherein the overlapping area covers the branch lightning rod, and the first conductor, the second conductor and the branch lightning rod are electrically connected.

[0008] Furthermore, a first groove is provided on the inner surface of the second conductor, and the overlapping area is an area where the first conductor is embedded in the first groove, and the inner surface of the first conductor after being embedded in the first groove is in contact with the upper surface of the branch lightning receptor.

[0009] Furthermore, the second conductor is a rectangular copper sheet surrounding the surface of the blade.

[0010] Furthermore, the first conductor is connected in series to a branch lightning receptor on the upper surface of the blade.

[0011] Furthermore, the first conductor is connected in series to branch lightning receptors on the upper and lower surfaces of the blade.

[0012] Furthermore, a first groove is provided on the upper surface of the second conductor, and the overlapping area is an area where the first conductor is embedded in the first groove.

[0013] Furthermore, the first conductor, the second conductor and the branch lightning receptor are connected through rivets.

[0014] Furthermore, the first conductor has a second groove at the overlapping area, and the end surface of the second groove is in contact with the upper surface of the branch lightning receptor.

[0015] Furthermore, the first groove is a dovetail groove.

[0016] A method for connecting a wind turbine blade branch lightning arrester is also proposed, which is characterized by adopting the above connection structure and comprising the following steps: S1, a first conductor of a certain length is manufactured according to the size of the blade body; S2, attaching the first conductor to the surface of the blade; S3, manufacturing a second conductor of a certain length according to the size of the blade body lightning receptor and the blade body, and opening a first groove on the inner surface of the second conductor and at the branch lightning receptor; S4, attaching the second conductor to the surface of the blade so that the first conductor is embedded in the first groove to form an overlapping area, opening a hole in the overlapping area, and fixing the first conductor, the second conductor and the branch lightning receptor by rivets.

[0017] Compared with the prior art, the technical solution of the present application has the following beneficial effects: the branch lightning rod connection structure and connection method proposed in the present invention increase the lightning rod area of ​​the blade body lightning rod, while improving the structural reliability of the blade body lightning rod, enhancing the guiding effect of lightning current, and reducing the damage of lightning current to the lightning protection mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 : Schematic diagram of branch lightning arrester connection structure; Figure 2 : Schematic diagram of the top of the branch lightning arrester connection structure; Figure 3 : Side view of the branch lightning arrester connection structure Figure 1 ; Figure 4 : Side view of the branch lightning arrester connection structure Figure 2 . DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] A connection structure of a wind turbine blade branch lightning receptor, comprising a branch lightning receptor 1 embedded in the surface of the blade, characterized in that it comprises a first conductor 2 extending along the length direction of the blade and attached to the surface of the blade, and also comprises a second conductor 3 attached to the surface of the blade and cross-stacked with the first conductor 2, wherein the first conductor 2 and the second conductor 3 have an overlapping area 4, the overlapping area 4 is connected to the branch lightning receptor 1, and the first conductor 2, the second conductor 3 and the branch lightning receptor 1 are electrically connected.

[0021] In this embodiment, see Figure 1 and Figure 2 , the branch lightning receptor 1 is electrically connected to the down conductor inside the blade, the first conductor 2 and the second conductor 3 are both attached to the surface of the blade and have an overlapping area 4, and the overlapping area 4 is connected to the branch lightning receptor 1, thereby forming an electrically connected whole, which expands the lightning reception area of ​​the branch lightning receptor 1, and the first conductor 2 and the second conductor 3 can be used for drainage, thereby strengthening the drainage capacity after lightning reception. After the first conductor 2 and the second conductor 3 are attached to the surface of the blade, on the one hand, the structure of the blade can be strengthened, and on the other hand, the two conductors are cross-stacked with each other, which can strengthen the connection structure between them and the branch lightning receptor 1, making the connection between the branch lightning receptor 1 and the first conductor 2 and the second conductor 3 more reliable. In this embodiment, the first conductor 2 is a guide strip extending along the length direction of the blade, and the second conductor 3 and the first conductor 2 are vertically distributed.

[0022] In a more preferred embodiment, the inner surface of the second conductor 3 is provided with a first groove 21, the overlapping area 4 is an area where the first conductor 2 is embedded in the first groove 21, and the inner surface of the first conductor 2 after being embedded in the first groove 21 is connected to the branch lightning receptor 1. Figure 3 As shown, in this embodiment, the first conductor 2 is connected as a whole after being embedded in the first groove 21, thereby improving the reliability of the connection between the two. As an alternative embodiment, the first groove 21 may be provided on the upper surface of the second conductor 3, and the overlapping area 4 is the area where the first conductor 2 is embedded in the first groove 21.

[0023] On the basis of the above-mentioned embodiment, the first groove 21 can preferably be a dovetail groove, which can have a larger contact area when the first conductor 2 and the second conductor 3 have the same width, and the connection is more stable. The width of the first conductor 2 and the second conductor 3 is preferably not less than the area of ​​the top of the branch lightning receptor 1, so that the overlapping area 4 formed by the two can completely cover the cross section of the branch lightning receptor 1, ensuring the lightning receptor area and strengthening the drainage capacity.

[0024] In a more preferred embodiment, see Figure 3 , the second conductor 3 is a rectangular copper sheet enclosing the blade surface. The length of the rectangular copper sheet can be determined by the sum of the lengths of the windward side and the leeward side of the blade body. After the rectangular copper sheet is attached to the blade body surface and encloses the blade surface as a whole, the first conductor 2 is buckled below by the second conductor 3 to form a whole, further improving the reliability of the connection structure.

[0025] In a more preferred embodiment, the first conductor 2 is connected in series with the branch lightning receptors 1 on the upper surface of the blade. In this embodiment, there is more than one branch lightning receptor 1 distributed on the surface of the single blade, and there may be multiple, for example, three to five. Each branch lightning receptor 1 is connected in series with the first conductor 2 using the same connection structure to form a whole, so that the lightning receptor area of ​​each branch lightning receptor 1 is expanded, and the drainage can be drained through the first conductor 2.

[0026] In a more preferred embodiment, the first conductor 2 is connected in series with the branch lightning receptors 1 on the upper and lower surfaces of the blade. Similar to the above embodiment, the branch lightning receptors 1 are distributed on both the windward and leeward surfaces of the blade in this embodiment, and are symmetrically distributed. When the first conductor 2 encloses the windward and leeward surfaces of the blade, the branch lightning receptors 1 on the upper and lower surfaces of the blade can also be connected in series, which improves the connection structure strength of the branch lightning receptors 1 on the upper and lower surfaces of the blade on the one hand, and also increases the lightning reception area and drainage capacity on the other hand.

[0027] A typical connection mode of the branch lightning receptor 1 may be that the first conductor 2, the second conductor 3 and the branch lightning receptor 1 are connected through rivets.

[0028] like Figure 4 As shown, in some embodiments of the blade branch lightning receptor 1, the top surface of the blade branch lightning receptor 1 protrudes a certain distance from the blade surface, so that the first conductor 2 can form a connected whole when connected to the top surface of the blade branch lightning receptor 1 and the second conductor is enclosed and superimposed on the first conductor 2, and the superimposed area can completely fit the blade surface curve as much as possible. In this embodiment, the first conductor 2 has a second groove 22 at the superimposed area 4, and the end surface of the second groove 22 fits the upper surface of the branch lightning receptor 1.

[0029] Based on the above implementation, the following implementation further proposes a connection method, and includes the following steps: S1, manufacturing a first conductor 2 of a certain length according to the size of the blade body; S2, attaching the first conductor 2 to the surface of the blade; S3, manufacturing a second conductor 3 of a certain length according to the size of the blade body lightning receptor and the blade body, and opening a first groove 21 on the inner surface of the second conductor 3 and at the branch lightning receptor 1; S4, attach the second conductor 3 to the surface of the blade so that the first conductor 2 is embedded in the first groove 21 to form an overlapping area 4, open a hole in the overlapping area 4, and fix the first conductor 2, the second conductor 3 and the branch lightning receptor 1 with rivets.

[0030] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A wind turbine blade branch lightning receptor connection structure, comprising a branch lightning receptor (1) embedded in the surface of the blade, characterized in that: The invention comprises a first conductor (2) extending in the length direction of the blade body and attached to the surface of the blade body, and a second conductor (3) attached to the surface of the blade body and cross-overlapping with the first conductor (2), wherein the first conductor (2) and the second conductor (3) have an overlapping region (4), and the overlapping region (4) is connected to a branch lightning receptor (1), and the first conductor (2), the second conductor (3) and the branch lightning receptor (1) are electrically connected.

2. The wind turbine blade branch lightning arrester connection structure according to claim 1, characterized in that: The second conductor (3) has a first groove (21) formed on its inner surface, the overlapping region (4) is a region where the first conductor (2) is embedded in the first groove (21), and the inner surface of the first conductor (2) after being embedded in the first groove (21) is connected to the branch lightning receptor (1).

3. The wind turbine blade branch lightning arrester connection structure according to claim 2, characterized in that: The second conductor (3) is a rectangular copper sheet surrounding the surface of the blade.

4. The wind turbine blade branch lightning arrester connection structure according to claim 3, characterized in that: The first conductor (2) is connected in series to the branch lightning receptor (1) on the upper surface of the blade.

5. The wind turbine blade branch lightning arrester connection structure according to claim 4, characterized in that: The first conductor (2) is connected in series to the branch lightning receptors (1) on the upper and lower surfaces of the blade.

6. The wind turbine blade branch lightning arrester connection structure according to claim 1, characterized in that: A first groove (21) is provided on the upper surface of the second conductor (3), and the overlapping area (4) is an area where the first conductor (2) is embedded in the first groove (21).

7. The wind turbine blade branch lightning arrester connection structure according to claim 2 or 6, characterized in that: The first conductor (2), the second conductor (3) and the branch lightning receptor (1) are connected through rivets.

8. The wind turbine blade branch lightning arrester connection structure according to claim 2, characterized in that: The first conductor (2) has a second groove (22) at the overlapping area (4), and the end surface of the second groove (22) is in contact with the upper surface of the branch lightning receptor (1).

9. The wind turbine blade branch lightning arrester connection structure according to claim 2 or 6, characterized in that: The first groove (21) is a dovetail groove.

10. A method for connecting a wind turbine blade branch lightning arrester, characterized in that: The connection structure as claimed in claim 2 is adopted, and comprises the following steps: S1, manufacturing a first conductor (2) of a certain length according to the size of the blade body; S2, attaching the first conductor (2) to the surface of the blade; S3, manufacturing a second conductor (3) of a certain length according to the size of the blade body lightning receptor and the blade body, and providing a first groove (21) on the inner surface of the second conductor (3) and at the branch lightning receptor (1); S4, attaching the second conductor (3) to the surface of the blade so that the first conductor (2) is embedded in the first groove (21) to form an overlapping area (4), opening a hole in the overlapping area (4), and fixing the first conductor (2), the second conductor (3) and the branch lightning receptor (1) by using rivets.

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