Wind power blade web integrated design method and wind power blade thereof

Abstract

The invention discloses a wind power blade web integration design method, which comprises the following steps of: laying a current-conducting plate in a cut-off part of a blade web, arranging a splicing sleeve on the current-conducting plate, and connecting the splicing sleeves of two adjacent blade webs through a down lead to connect the adjacent blade webs into a whole, therefore, the risk of failure of the lightning protection system caused by fracture of the lightning protection downlead due to mechanical stress generated by deformation is reduced. The current-conducting plate is laid in the blade web to replace a main down lead, the blade tip lightning arrester is connected with the current-conducting plate through the down lead with a certain length, the risk that a lightning protection system fails due to breakage caused by mechanical stress generated by deformation of the down lead in the later period is reduced, and the safety performance of fan operation is improved.

Description

Technical Field

[0001] The invention relates to a method for designing an integrated web of a wind turbine blade and a wind turbine blade thereof, belonging to the technical field of lightning protection for wind turbine blades. Background Art

[0002] The existing lightning protection down conductor is led out from the starting position of the blade web to the blade root, and then is directly straightened and fixed on the metal flange of the blade root. The straightened down conductor is bonded to the inner wall of the blade by structural bonding or other glue, and is fixed on the surface of the down conductor by hand-pasting glass fiber cloth or covering the glass fiber reinforced plastic pressure plate. The down conductor is connected to the flange through a single-hole copper nose. There are two ways to connect the single-hole copper nose to the flange. One is to directly punch a bolt hole to connect to the flange; the other is to weld a connecting piece on the flange to connect to the copper nose. Both of these connection methods have large contact resistance, and the second method is less reliable than the first.

[0003] The lightning protection down conductor is fixed in a straight line from the starting point of the blade web to the blade root flange, and the down conductor is in a taut state. During the operation of the wind turbine, the blades will vibrate, and the down conductor will deform with the vibration of the blades. If the wire is in a taut state, it will be torn off, and the copper nose connected to the flange will also be pulled off during the deformation process, which will cause the lightning protection system of the blade to fail, causing the wind turbine to be damaged by lightning.

[0004] After searching, CN112483335A discloses a wind turbine blade lightning protection system and a wind turbine blade. The lightning protection component includes a lightning protection ring, a cap-shaped glass fiber reinforced plastic washer, a connecting ear and a carbon brush. The lightning protection ring is connected to the connecting ear and the carbon brush respectively. The end of the connecting ear away from the lightning protection ring is connected to a copper wire. The carbon brush is connected to the blade hub. The copper wire conducts lightning to the lightning protection ring through the connecting ear. The lightning received by the lightning protection ring is conducted to the blade hub through the carbon brush. The lower end face of the cap-shaped glass fiber reinforced plastic washer is bonded to the blade root. The cap-shaped glass fiber reinforced plastic washer is assembled from two completely identical half-cap-shaped glass fiber reinforced plastic washers. The lightning protection ring is welded from two semicircular rings. Bolts are sequentially passed through the semicircular ring and the semi-cap-shaped glass fiber reinforced plastic washer and then threadedly connected with a nut to connect the semicircular ring and the semi-cap-shaped glass fiber reinforced plastic washer. The lightning protection ring does not emerge from the top of the bolt. While ensuring lightning conductivity, the lightning protection component can be simply and firmly bonded to the outer surface of the blade root shell. The patented connection between the stainless steel lightning protection ring and the blade root focuses on the installation quality of the lightning protection ring to avoid the falling off of the lightning protection component, rather than the fixing structure and method of the lightning protection down conductor at the blade root.

[0005] CN115681027A discloses a root end fixing structure and fixing method of a lightning protection wire for a wind turbine blade, comprising a wire fixed on a blade, wherein the wire is bent at the starting point of the leading edge blade web and the starting point of the trailing edge blade web on the blade, and the outer side of the wire is fixed on the blade by hand-laid glass fiber cloth and a glass fiber reinforced plastic pressure plate, and the hand-laid glass fiber cloth is disconnected at the crest position of the bending of the wire; the wire is connected to the flange through a copper nose after passing through the baffle position; the wire is bent and wired when the blade root is fixed, and a small section of active margin is reserved to prevent the wire from being tightened during the later deformation process. This method optimizes the fixing method of the blade root wire, eliminates the risk of failure of the lightning protection system due to the breakage of the blade root wire and the copper nose, and improves the safety performance of the wind turbine operation. It can effectively prevent the blade root wire from being torn off during the deformation process, and avoid the risk of the copper nose being pulled off when the blade root wire is deformed. The focus of this patent is to eliminate the mechanical stress of the root end fixation.

[0006] In summary, it is very necessary to invent a solution to the problem that long-term operation of the fan will cause the down conductor and the flange to be disconnected, resulting in lightning protection failure. Summary of the invention

[0007] In order to address the deficiencies in the prior art, the present invention provides an integrated design method for a wind turbine blade web, in which a conductive plate is laid in the blade web instead of the main down conductor, and the blade tip lightning arrester is connected to the conductive plate through a down conductor of a certain length, thereby reducing the risk of failure of the lightning protection system due to breakage caused by mechanical stress generated by deformation of the down conductor in the later stage, thereby improving the safety performance of the wind turbine operation.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is: Disclosed is a method for designing an integrated wind turbine blade web. A conductive plate is laid in a cut-off portion of the blade web. A connecting pipe is arranged on the conductive plate. The connecting pipe connects two adjacent blade webs via a down conductor to connect the adjacent blade webs into one, so as to reduce the risk of failure of the lightning protection system due to breakage caused by mechanical stress generated by deformation of the lightning protection down conductor.

[0009] The wind turbine blade web integrated design method of the present invention optimizes the fixing method of the down conductor, reduces the possibility of the blade root down conductor being broken due to mechanical stress generated by deformation in the later stage, improves the reliability of the down conductor, and further reduces the risk of lightning protection failure; by adding a conductive plate, the skin effect of the current is reduced and the current drainage capacity of the blade tip is improved; when connecting, the length of the down conductor is reduced and the cost is reduced; the down conductor in the high-voltage area of ​​the blade tip is connected to the conductive plate, and during the current transmission process, the current drainage capacity of the high-voltage area is improved.

[0010] Furthermore, the conductive plate is laid extending from the edge of the blade web cut-off portion to the inside. The conductive plate can be square or other shapes, preferably rectangular for easy processing, and can be attached to the blade web cut-off portion, easy to install, and strong in stability.

[0011] Furthermore, along the width direction of the blade web, the ratio of the length of the conductive plate to the width of the blade web is 1:2-4; the ratio of the width of the conductive plate to the length of the conductive plate is 1:5-6; the ratio of the thickness of the conductive plate to the thickness of the blade web is 1:6-8. The size of this conductive plate ensures both the tip drainage capability and the installation reliability.

[0012] Furthermore, the connecting pipe includes a fixing portion and a connecting portion, the fixing portion is a flat arch or N-shaped structure, the connecting portion extends from the fixing portion to the outer side of the edge of the truncated portion of the blade web, and the connecting portion is a hollow sleeve to accommodate and fix the down conductor. The structure of the connecting pipe plays a transitional connection role, which can ensure the orderly connection of adjacent conductive plates and also form a conductive path between the down conductor and the conductive plate.

[0013] Furthermore, mounting holes are provided on the fixing part and the conductive plate, and the fixing is performed by bolts. The connecting pipe is made of conductive copper material, and the fixing by bolts is simple and easy to operate, and does not increase the production cost.

[0014] Furthermore, the blade web comprises mutually parallel side plates and a bottom plate connected to the side plates, and the conductive plate is installed in the bottom plate. This design is not only convenient for molding, but also can enhance the installation stability of the connecting pipe.

[0015] Furthermore, the hollow sleeve is coated with a carbon fiber cloth layer, so that the entire connecting pipe is wrapped in the blade fiber to prevent damage or short circuit caused by continuous exposure to air and moisture.

[0016] Furthermore, the conductive plate is a copper plate, the copper plates are one or more stacked, and the mounting holes of the stacked copper plates are concentrically arranged. This arrangement can select the required specifications of the conductive plate according to different requirements of the blades, and has stronger versatility.

[0017] Furthermore, the length of the down conductor is greater than the thickness of the stacked webs of two adjacent blades. This arrangement ensures that the down conductor will not be easily disconnected due to pulling.

[0018] Another object of the present invention is to disclose a wind turbine blade manufactured by the above-mentioned wind turbine blade web integrated design method.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The wind turbine blade web integrated design method of the present invention optimizes the fixing method of the down conductor, reduces the possibility of the blade root down conductor being broken due to mechanical stress generated by deformation in the later stage, improves the reliability of the down conductor, and further reduces the risk of lightning protection failure; by adding a conductive plate, the skin effect of the current is reduced and the current drainage capacity of the blade tip is improved; when connecting, the length of the down conductor is reduced and the cost is reduced; the down conductor in the high-voltage area of ​​the blade tip is connected to the conductive plate, and during the current transmission process, the current drainage capacity of the high-voltage area is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of a wind turbine blade prepared by the wind turbine blade web integrated design method described in the present invention.

[0021] Figure 2 A schematic diagram of the internal structure of a wind turbine blade prepared by the wind turbine blade web integrated design method of the present invention.

[0022] Figure 3 for Figure 2 An enlarged schematic diagram of point B of a wind turbine blade prepared by the wind turbine blade web integrated design method.

[0023] Figure 4 This is a schematic diagram of the folded state of a wind turbine blade prepared by the wind turbine blade web integrated design method of the present invention. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with the accompanying drawings. Figure 1-4 The drawings are only for illustrative purposes and are not physical drawings. They cannot be construed as limiting the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings. The specific implementation method is as follows. Example 1

[0025] In the wind turbine blade web integrated design method of the present embodiment, a conductive plate 2 is laid in the cut-off portion of the blade web 1, a connecting pipe 3 is arranged on the conductive plate 2, and the connecting pipe 3 of two adjacent blade webs 1 is connected by a down conductor 4 to connect the adjacent blade webs 1 into one, so as to reduce the risk of failure of the lightning protection system due to breakage caused by mechanical stress generated by deformation of the lightning protection down conductor.

[0026] In order to facilitate processing, the conductive plate can be square or other shapes, preferably a rectangular plate, which can be attached to the cut-off part of the blade web, is easy to install, and has strong stability. The conductive plate 2 in this embodiment is a rectangular sheet, extending from the edge of the cut-off part of the blade web 1 to the inside. Along the width direction of the blade web 1, the ratio of the length of the conductive plate 2 to the width of the blade web 1 is 1:2-4, and 1:3 in this embodiment; the ratio of the width of the conductive plate 2 to the length of the conductive plate 2 is 1:5-6, and 1:5 in this embodiment; the ratio of the thickness of the conductive plate 2 to the thickness of the blade web 1 is 1:6-8, and 1:8 in this embodiment. The size of this conductive plate ensures both the tip drainage capacity and installation reliability.

[0027] More specifically, the connecting pipe 3 includes a fixing portion 31 and a connecting portion 32. The fixing portion 31 is a flat arch or N-shaped structure. The connecting portion 32 extends from the fixing portion 31 to the outer side of the edge of the cut-off portion of the blade web 1. The connecting portion 32 is a hollow sleeve to accommodate and fix the down conductor. The outer surface of the hollow sleeve is covered with a carbon fiber cloth layer. The structure of the connecting pipe plays a transitional connection role, which can ensure the orderly connection of adjacent conductive plates while allowing the down conductor and the conductive plate to form a conductive path. The entire connecting pipe is wrapped in the blade fiber to prevent damage or short circuit and other adverse effects caused by continuous exposure to moisture in the air.

[0028] The fixing part 31 and the conductive plate 2 are provided with mounting holes, and are fixed by bolts. The connecting pipe is set to be a conductive copper material, and the fixing by bolts is simple and easy to operate, and does not increase the production cost.

[0029] In this embodiment, the blade web 1 includes mutually parallel side plates 11 and a bottom plate 12 connected to the side plates 11, and the conductive plate 2 is installed in the bottom plate 12. The conductive plate 2 is a copper plate, and the copper plates are one or more stacked copper plates, and the mounting holes of the stacked copper plates are concentrically arranged. The copper plate in this embodiment is a whole plate.

[0030] In order to ensure that the down conductor will not be easily disconnected due to pulling, the length of the down conductor is greater than the thickness of the stacked webs of two adjacent blades.

[0031] The integrated design method for the web of a wind turbine blade in this embodiment is to manufacture several copper plates according to the specifications of the web and the down conductor, and lead out connecting pipes (the two ends of the copper nose are flattened and punched, and fixed by bolts) from the ends of the copper plates where the two webs are cut, and connect the blade tip lightning arrester to the connecting pipe on the copper plate (one end of the copper nose is flattened and punched, and fixed to the copper plate by bolts, and the other end is pressed tightly to the high-voltage down conductor) through a down conductor of a certain length.

[0032] The wind turbine blade web integrated design method of the present invention optimizes the fixing method of the down conductor, reduces the possibility of the blade root down conductor being broken due to mechanical stress generated by deformation in the later stage, improves the reliability of the down conductor, and further reduces the risk of lightning protection failure; by adding a conductive plate, the skin effect of the current is reduced and the current drainage capacity of the blade tip is improved; when connecting, the length of the down conductor is reduced and the cost is reduced; the down conductor in the high-voltage area of ​​the blade tip is connected to the conductive plate, and during the current transmission process, the current drainage capacity of the high-voltage area is improved.

[0033] The above are only embodiments of the present invention. The invention is not limited to the field involved in this implementation case. The common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the content of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for designing an integrated web of a wind turbine blade, characterized in that: A conductive plate is laid in the cut-off part of the blade web, and a connecting pipe is arranged on the conductive plate. The adjacent blade webs are connected as a whole through the connecting pipe of the down conductor connecting two adjacent blade webs, so as to reduce the risk of failure of the lightning protection system due to breakage caused by mechanical stress generated by deformation of the lightning protection down conductor.

2. The method for integrated design of the web of a wind turbine blade according to claim 1, characterized in that: The conductive plate is in the shape of a rectangular sheet and is laid inwardly extending from the edge of the cut-off portion of the blade web.

3. The integrated design method for the web of a wind turbine blade according to claim 2 is characterized in that: Along the width direction of the blade web, the ratio of the length of the conductive plate to the width of the blade web is 1:2-4; the ratio of the width of the conductive plate to the length of the conductive plate is 1:5-6; and the ratio of the thickness of the conductive plate to the thickness of the blade web is 1:6-8.

4. The integrated design method for the web of a wind turbine blade according to claim 1 is characterized in that: The connecting pipe includes a fixing part and a connecting part. The fixing part is a flat arch or N-shaped structure. The connecting part extends from the fixing part to the outer side of the edge of the blade web cut-off part. The connecting part is a hollow sleeve to accommodate and fix the down conductor.

5. The integrated design method for the web of a wind turbine blade according to claim 4 is characterized in that: Mounting holes are provided on the fixing part and the conductive plate, and the fixing parts are fixed by bolts.

6. The integrated design method for the web of a wind turbine blade according to claim 5 is characterized in that: The blade web comprises side plates parallel to each other and a bottom plate connected to the side plates, and the conductive plate is installed in the bottom plate.

7. The integrated design method for the web of a wind turbine blade according to claim 6, characterized in that: The hollow sleeve is conformally coated with a carbon fiber cloth layer.

8. The method for integrated design of the web of a wind turbine blade according to any one of claims 1 to 7, characterized in that: The conductive plate is a copper plate, and the copper plates are one or more stacked copper plates, and the mounting holes of the stacked copper plates are concentrically arranged.

9. The integrated design method for the web of a wind turbine blade according to claim 8, characterized in that: The length of the down conductor is greater than the thickness of the stacked webs of two adjacent blades.

10. A wind turbine blade manufactured using the wind turbine blade web integrated design method according to any one of claims 1 to 9.

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