A wind turbine blade and a method of forming

Abstract

The application relates to the technical field of wind power equipment, in particular to a wind power blade and a forming method. The wind power blade comprises a blade body, a main beam, a metal foil and a carbon fiber layer. An accommodating space is arranged in the inside of the blade body. The main beam is arranged in the accommodating space. The metal foil is connected with the outer surface of the blade body, and the metal foil is connected with a ground wire. The carbon fiber layer is arranged between the blade body and the metal foil, and the metal foil, the carbon fiber layer and the blade body are sequentially and layerwisely connected from the outside of the blade body to the inside. The wind power blade has the following advantages: lightning strike protection of the carbon fiber blade is more targeted, blade rapid infusion is facilitated, and infusion defects are avoided; an equipotential balance channel of the carbon fiber main beam and the surface metal foil is realized, carbon fiber internal lightning current is rapidly discharged, and carbon fiber lightning strike damage is avoided; the forming is simple, the cost is low, the lightning protection effect is safe and reliable, and the service life is long.

Description

Technical Field

[0001] This invention relates to the field of wind power equipment technology, and in particular to a wind turbine blade and its forming method. Background Technology

[0002] Vast areas of the Earth, such as grasslands, mountains, and oceans, are relatively open and windy. Because these areas have no obstructions, wind power is strong. Therefore, many wind power plants have been built in these regions to effectively utilize wind power and convert it into electricity, providing power to people while saving a significant amount of energy. With the development of wind power, wind power equipment has also been continuously improved. In recent years, the trend towards larger and lighter wind turbine blades has driven the demand for carbon fiber wind turbine blades. Due to its excellent properties, carbon fiber, when used in wind turbine blades, allows for longer blades and lighter weight, further improving the utilization rate of wind energy, especially in the main beams of wind turbine blades.

[0003] However, these areas experience strong winds and are frequently struck by lightning. Carbon fiber is a poor conductor, easily attracting lightning but failing to disperse it quickly, causing severe damage to the blade structure and incurring significant maintenance costs. Currently, commonly used carbon fiber blades feature a carbon fiber main beam and glass fiber for the rest of the shell. The carbon fiber main beam is laid inside the blade, while the glass fiber is laid on the blade surface. A common lightning protection method involves laying a large metal mesh over the entire carbon fiber main beam area from tip to root, using the mesh to receive and conduct lightning.

[0004] Chinese utility model patent CN209959402U discloses a novel lightning-resistant wind turbine blade, comprising a blade body including an outer shell and an inner shell. Carbon fiber filler is used to fill the space between the outer and inner shells. The outer shell has a tip lightning arrester and three center lightning arresters on its surface. Lightning-absorbing strips, arranged in a wavy pattern, are alternately positioned between the tip and center lightning arresters on the outer shell surface. A lightning protection network is installed inside the inner shell, with a surge arrester connected to one end of the network. The surge arrester is connected to an external grounding device. The tip and three center lightning arresters are all connected to the lightning protection network via wires. This utility model, by incorporating a lightning protection network and surge arresters, facilitates the dissipation of ionization by the surge arresters, and the remaining ionization is conducted to the ground through the grounding device, thereby preventing excessive lightning current from damaging the blade.

[0005] However, according to statistics, most lightning strikes occur at the edge of the carbon fiber main beam, and the lightning cannot be quickly conducted to the surface metal mesh after the carbon fiber main beam is struck by lightning. This is mainly because there is no potential balance connection channel between the carbon fiber main beam and the metal mesh, and the lightning current on the carbon fiber cannot be quickly discharged to the surface metal mesh. Summary of the Invention

[0006] In view of this, the present invention aims to provide a wind turbine blade, which adopts a metal foil on the main beam on the outer surface of the blade body, and a carbon fiber cloth between the metal foil and the blade body, which solves the problem that there is no potential balance connection channel and the lightning current on the carbon fiber cannot be quickly discharged to the surface metal mesh.

[0007] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0008] A wind turbine blade includes: a blade body, wherein an accommodating space is provided inside the blade body;

[0009] The main beam is disposed within the accommodating space;

[0010] A metal foil is connected to the outer surface of the blade body, and the metal foil is connected to the ground wire;

[0011] A carbon fiber layer is disposed between the blade body and the metal foil, and the metal foil, the carbon fiber layer and the blade body are sequentially stacked and connected from the outside to the inside of the blade body.

[0012] Furthermore, the main beam extends from the tip of the blade body towards the root;

[0013] The metal foil comprises:

[0014] A leading edge foil is disposed near the leading edge side of the blade body and extends from the root to the tip;

[0015] A trailing edge foil is disposed near the trailing edge side of the blade body and extends from the root to the tip;

[0016] The leading edge foil and the trailing edge foil are connected at the tip.

[0017] Furthermore, the width of the main beam is less than the distance between the leading edge foil and the trailing edge foil;

[0018] The leading edge foil and the trailing edge foil are symmetrically arranged in the direction from the leading edge to the trailing edge.

[0019] Furthermore, the wind turbine blade also includes:

[0020] The lightning arrester is located at the tip of the blade body.

[0021] Furthermore, the connection end of the leading edge foil and the trailing edge foil at the tip is the lightning arrester.

[0022] Furthermore, the metal disk includes a front disk connected to the leading edge foil and a rear disk connected to the trailing edge foil;

[0023] The metal foil is held in place on the outer surface of the root by the front plate and the rear plate.

[0024] Furthermore, the ground wire is connected to the metal disk.

[0025] Furthermore, the carbon fiber layer comprises:

[0026] Carbon fiber felt is attached and connected to the main beam;

[0027] Carbon fiber cloth is disposed between the carbon fiber felt and the metal foil, and is respectively bonded and connected to the carbon fiber felt and the metal foil.

[0028] Furthermore, an outer skin is laid on the area outside the metal foil on the outer surface of the blade body.

[0029] A method for forming a wind turbine blade, wherein the wind turbine blade is a wind turbine blade as described in any one of the above claims, the forming method comprising:

[0030] S100. Lay the metal foil on the surface of the blade body mold, then lay the outer skin, and remove the outer skin fabric in the metal foil area.

[0031] S200: Fill the blade body mold with carbon fiber cloth, then lay carbon fiber felt in the main beam area, lay the main beam on the carbon fiber felt, fill with carbon fiber material, and then perform vacuum resin injection.

[0032] S300. After the blade is demolded, connect the ground wire of the metal disc at the root of the blade. The ground wires converge at the root of the blade to form a ground.

[0033] Compared with existing technologies, the wind turbine blade of the present invention has the following advantages:

[0034] The advantages of this technical solution are that metal foil is set on both sides of the carbon fiber main beam, which provides more targeted lightning protection for the carbon fiber blades; the carbon fiber felt laid on the lower layer of the main beam area facilitates rapid blade injection and avoids injection defects; by setting carbon fiber cloth, an equipotential balance channel is achieved between the carbon fiber main beam and the surface metal foil, which facilitates rapid discharge of lightning current inside the carbon fiber and avoids lightning damage to the carbon fiber; the lightning protection wind turbine blade of this invention is simple to form, low in cost, safe and reliable in lightning protection effect, and has a long service life. Attached Figure Description

[0035] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0036] Figure 1 This is a schematic diagram of a wind turbine blade according to an embodiment of the present invention;

[0037] Figure 2 This is a cross-sectional view of the wind turbine blade described in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the metal foil grounding structure according to an embodiment of the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1-Blade body, 101-Outer skin, 2-Main beam, 3-Metal foil, 31-Leading edge foil, 32-Leading edge foil, 4-Carbon fiber layer, 41-Carbon fiber felt, 42-Carbon fiber cloth, 5-Ground wire, 6-Metal disk. Detailed Implementation

[0041] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0042] In this invention, the terms "first," "second," "upper," and "lower," etc., are used for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," "upper," or "lower" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. Where the technical solutions of the embodiments can be combined, they are all within the scope of protection claimed by this invention.

[0043] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0044] like Figure 1 and Figure 2 As shown, a wind turbine blade includes: a blade body 1, a main beam 2, a metal foil 3, and a carbon fiber layer 4. An accommodating space is provided inside the blade body 1. The main beam 2 is disposed within the accommodating space. The metal foil 3 is connected to the outer surface of the blade body 1 and is also connected to a ground wire 5. The carbon fiber layer 4 is disposed between the blade body 1 and the metal foil 3. From the outside of the blade body 1 inwards, the metal foil 3, the carbon fiber layer 4, and the blade body 1 are sequentially stacked and connected.

[0045] Metal foil 3 is installed on both sides of the carbon fiber main beam 2 for more targeted lightning protection of the carbon fiber blades. The carbon fiber felt 41 laid under the main beam 2 area facilitates rapid blade infilling and avoids infilling defects. The carbon fiber cloth 42 creates an equipotential balance channel between the carbon fiber main beam 2 and the surface metal foil 3, which facilitates rapid discharge of lightning current inside the carbon fiber, preventing lightning damage. The lightning-protected wind turbine blades of this invention are simple to form, low in cost, and offer reliable lightning protection with a long service life. In this embodiment, the metal foil is made of one of copper, aluminum, stainless steel, and nickel, with a thickness ranging from 0.05 to 5 mm, preferably 0.1 to 3 mm.

[0046] Specifically, the main beam 2 extends from the tip to the root of the blade body 1. The metal foil 3 includes a leading edge foil 31 and a trailing edge foil 32. The leading edge foil 31 is disposed near the leading edge of the blade body 1 and extends from the root to the tip. The trailing edge foil 32 is disposed near the trailing edge of the blade body 1 and extends from the root to the tip. The leading edge foil 31 and the trailing edge foil 32 are connected at the tip.

[0047] Furthermore, the width of the main beam 2 is less than the distance between the leading edge foil 31 and the trailing edge foil 32. The leading edge foil 31 and the trailing edge foil 32 are symmetrically arranged in the direction from the leading edge to the trailing edge.

[0048] The leading edge foil 31 and trailing edge foil 32 of the metal foil 3 are respectively set on both sides of the leading edge and trailing edge of the blade body 1, so that the carbon fiber main beam 2 and the metal foil 3 form a potential balance connection channel. The metal foil 3 intercepts the lightning in the area of ​​the carbon fiber main beam 2 and conducts it to the root ground. It can quickly discharge the lightning current on the carbon fiber to the surface metal foil 3, effectively protecting the carbon fiber main beam 2.

[0049] Furthermore, the wind turbine blade also includes a lightning arrester (not shown in the figure), which is disposed at the tip of the blade body 1.

[0050] The lightning arrester is a component installed on the blade body 1 to receive lightning strikes. It is connected to the ground and directs the lightning current to the ground, effectively protecting the blade body 1 and the main beam 2.

[0051] Furthermore, the connection end of the leading edge foil 31 and the trailing edge foil 32 at the tip is the lightning arrester.

[0052] The leading edge foil 31 and the trailing edge foil 32 are connected as one piece at the tip, and the metal foil 3 part at the tip position is used as a lightning arrester, which simplifies the structure of the blade, saves the connection device between the lightning arrester and the metal foil 3, and facilitates manufacturing, installation and daily maintenance.

[0053] Furthermore, the metal disc 6 includes a front disc connected to the leading edge foil 31 and a rear disc connected to the trailing edge foil 32. The metal foil 3 is held in place on the outer surface of the root by the front disc and the rear disc.

[0054] The front plate and the rear plate can be connected to the leading edge foil 31 and the trailing edge foil 32 by welding, respectively.

[0055] Furthermore, the ground wire 5 is connected to the metal disk 6.

[0056] The ground wire 5 is connected to the metal foil 3 through the metal disc 6, which makes installation convenient.

[0057] Furthermore, the carbon fiber layer 4 includes a carbon fiber felt 41 and a carbon fiber cloth 42. The carbon fiber felt 41 is bonded to the main beam 2. The carbon fiber cloth 42 is disposed between the carbon fiber felt 41 and the metal foil 3, and is bonded to both the carbon fiber felt 41 and the metal foil 3.

[0058] Furthermore, the width of the carbon fiber cloth 42 is comparable to the width of the metal foil 3, and the thickness is comparable to the thickness of the outer skin 101 of the blade body 1. The material of the carbon fiber cloth 42 is the same as the carbon fiber material used for the main beam 2.

[0059] Carbon fiber felt 41 is laid on the lower layer of carbon fiber main beam 2, in direct contact with carbon fiber main beam 2, which facilitates the impregnation of carbon fiber main beam 2. The width of carbon fiber felt 41 is wider than that of carbon fiber main beam 2. Carbon fiber cloth 42 is located on the lower layer of carbon fiber felt 41 and the upper layer of metal foil 3, in direct contact with carbon fiber felt 41 and metal foil 3, forming a potential balance channel between carbon fiber main beam 2 and surface metal foil 3, which is conducive to the rapid discharge of lightning current inside carbon fiber main beam 2.

[0060] Furthermore, an outer skin 101 is laid on the area outside the metal foil 3 on the outer surface of the blade body 1.

[0061] A method for forming a wind turbine blade, wherein the wind turbine blade is a wind turbine blade as described in any one of the above claims, the forming method comprising:

[0062] S100. Lay the metal foil on the surface of the blade body mold, then lay the outer skin, and remove the outer skin fabric in the metal foil area.

[0063] S200: Fill the blade body mold with carbon fiber cloth, then lay carbon fiber felt in the main beam area, lay the main beam on the carbon fiber felt, fill with carbon fiber material, and then perform vacuum resin injection.

[0064] S300. After the blade is demolded, connect the ground wire of the metal disc at the root of the blade. The ground wires converge at the root of the blade to form a ground.

[0065] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the following claims.

[0066] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A wind turbine blade, characterized in that, The wind turbine blade comprises: a blade body (1) having an accommodating space inside; a main beam (2) arranged in the accommodating space; a metal foil (3) connected to the outer surface of the blade body (1), and the metal foil (3) is connected to a ground wire (5); a carbon fiber layer (4) arranged between the blade body (1) and the metal foil (3), and the metal foil (3), the carbon fiber layer (4) and the blade body (1) are sequentially laminated and connected from the outside to the inside of the blade body (1), and the carbon fiber layer (4) comprises: a carbon fiber felt (41) connected to the main beam (2); a carbon fiber cloth (42) arranged between the carbon fiber felt (41) and the metal foil (3) and connected to the carbon fiber felt (41) and the metal foil (3) respectively.

2. The wind turbine blade according to claim 1, wherein: the main beam (2) extends from the tip to the root of the blade body (1); the metal foil (3) comprises: a leading edge foil (31) arranged near the leading edge side of the blade body (1) and extending from the root to the tip; a trailing edge foil (32) arranged near the trailing edge side of the blade body (1) and extending from the root to the tip; the leading edge foil (31) and the trailing edge foil (32) are connected at the tip.

3. The wind turbine blade according to claim 2, wherein: the width of the main beam (2) is smaller than the distance between the leading edge foil (31) and the trailing edge foil (32); the leading edge foil (31) and the trailing edge foil (32) are symmetrically arranged in the direction from the leading edge to the trailing edge.

4. A wind turbine blade according to claim 2, characterised in that Further comprising: a lightning arrester arranged at the tip of the blade body (1).

5. The wind turbine blade according to claim 4, wherein: the connection end of the leading edge foil (31) and the trailing edge foil (32) at the tip is the lightning arrester.

6. The wind turbine blade according to claim 5, wherein: the metal disc (6) comprises a front disc connected to the leading edge foil (31) and a rear disc connected to the trailing edge foil (32); the metal foil (3) is clamped by the front disc and the rear disc on the outer surface of the root.

7. The wind turbine blade according to claim 6, wherein: the ground wire (5) is connected to the metal disc (6).

8. The wind turbine blade according to claim 1, wherein: an outer skin (101) is laid on the area outside the metal foil (3) on the outer surface of the blade body (1).

9. A method of forming a wind turbine blade, the wind turbine blade being as claimed in any of claims 1 to 8, characterised in that, The forming method comprises: S100, laying a metal foil on the surface of a blade body mold, then laying an outer skin, and removing the skin cloth in the metal foil area; S200, filling carbon fiber cloth in the blade body mold, then laying carbon fiber felt in the main beam area, laying the main beam on the carbon fiber felt, and performing vacuum resin infusion after filling the carbon fiber material; S300, connecting the blade root to the metal disc ground wire after demolding the blade, and the ground wire is gathered into one ground wire at the blade root.

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