A highly reliable installation method for the leading edge protective cover of a wind turbine blade

Abstract

This invention relates to the field of wind turbine blades, specifically providing a leading-edge protective cover for wind turbine blades and its highly reliable installation method. The protective cover is formed by sequentially stacking multiple protective cover segments longitudinally from the blade tip to the blade root to form a pre-formed protective cover, which is then installed onto the blade. The protective cover segments are made of highly elastic material, and their cross-sections are generally U-shaped. The installation method of this invention includes the following steps: S1: roughening the leading-edge surface of the blade blank by grinding; S2: impregnating cut fiberglass cloth with resin and laying it onto the leading-edge surface of the blade blank; S3: attaching the inner side of the pre-formed protective cover to the fiberglass cloth; S4: laying auxiliary vacuum material around the perimeter of the pre-formed protective cover and heating and curing it; S5: after curing, removing the vacuum material and applying putty and paint around the perimeter of the pre-formed protective cover to produce the final leading-edge protective cover product. The leading-edge protective cover in this solution has good adhesion and the process is simple and efficient.

Description

Technical Field

[0001] This invention relates to the field of wind turbine blade technology, and in particular to a highly reliable installation method for a leading edge protective cover for wind turbine blades. Background Technology

[0002] Wind energy, as a pollution-free, renewable, and green energy source, has enormous development potential, especially for coastal islands, remote mountainous areas, grasslands, pastures, and rural and border regions far from or difficult to reach by the power grid in the short term. It is of great significance as a reliable way to solve energy problems for production and daily life. Wind energy has the advantages of low energy consumption, environmental friendliness, and large reserves. The typical way to utilize wind energy is to convert wind energy into electrical energy using wind turbines, thereby generating electricity through wind power.

[0003] Wind turbine blades are the core components of wind power generation systems. With the increasing size of wind turbine blades, the issue of leading-edge protection has arisen. The leading edge is the primary shear point of the blade. When the blade rotates at high speed, the speed at the blade tip typically exceeds 90 m / s. When raindrops impact the blade tip surface, they generate extremely high pressure (the impact pressure of a 1-3 mm raindrop can reach 120 MPa), making the blade tip the most susceptible to corrosion. Under normal circumstances, in harsh wind farms, the leading-edge protective material will fail after 3-5 years, leading to corrosion due to lack of protection. Once corrosion occurs at the leading edge, the aerodynamic performance of the blade deteriorates, affecting power generation performance. Severe leading-edge corrosion can result in an annual power generation loss of more than 25%, and this damage will continue to intensify over time, potentially leading to accidental damage or even serious accidents, ultimately causing significant economic losses to wind power operators. To protect the leading edge, the industry typically installs a protective cover on the windward ridge of the leading edge of the wind turbine blade to prevent damage. In the prior art, the following patents relate to the protection of the leading edge of wind turbine blades:

[0004] 1. Patent application with publication number "CN109790816A" and patent name "Wind turbine blade including protective cover" discloses a method for manufacturing a protective cover by attaching an adhesive layer along the blade. The adhesive forms a joint between the outer edge of the cover section of the blade and the surface of the blade, and the joint forms an inclined surface from the outer edge to the surface of the blade.

[0005] 2. Patent publication number “WO2016 / 075619A1” discloses a preformed protective cover for wind turbine blades, made of a polymer material such as polyether-based polyurethane. The interior of the preformed protective cover is adhered to the surface of the longitudinal edge of the wind turbine blade. The preformed protective cover extends longitudinally and has a U-shaped cross-section. The interior of the preformed protective cover is pressed against the edge of the longitudinal surface of the wind turbine blade by providing an adhesive on the interior side of the preformed protective cover, and excess adhesive leaking between each outer cover section and the surface of the longitudinal edge of the wind turbine blade is removed for bonding.

[0006] 3. Patent publication number CN110431303A, entitled "Leading Edge Protective Cover, Wind Turbine Blade, and Method for Preparing Wind Turbine Blade," describes a protective cover comprising a first longitudinally extending edge and a second longitudinally extending edge, as well as an outer arcuate surface and an inner arcuate surface extending between them. The first longitudinally extending edge is attached to the suction side of the wind turbine blade. The protective cover also includes a plurality of vortex-generating components positioned on the outer arcuate surface of the protective cover, at least a portion of which is along the first longitudinally extending edge. This solution enhances the protection of wind turbine blades from impact particles and improves the fluid characteristics on the surface of the wind turbine blade.

[0007] However, the aforementioned patents still have the following problems:

[0008] 1. Impact on aerodynamic shape: The aerodynamic shape of wind turbine blades is optimal when they are not attached to the protective cover. The existing technical solution is to use adhesive to attach the pre-formed protective cover to the already painted leading edge surface of the blade. In order to solve the step problem between the edge of the protective cover and the blade surface, a joint is formed by adhesive to create a smooth transition surface. Even with the U-shaped cross-section structural design of the protective cover and the smooth transition of the step, it is still inevitable that it will have an adverse effect on the aerodynamic shape.

[0009] 2. The inner side of the protective cover is generally bonded to the leading edge surface of the blade using adhesive or pressure-sensitive tape. Due to the variation in the curvature of the leading edge of the blade, firstly, when using adhesive bonding, the thickness of the adhesive layer is not easy to control. Therefore, the outer surface of the protective film will inevitably show unevenness, which affects the overall smoothness of the protective film surface and has a negative impact on conformability. Secondly, when using pressure-sensitive tape, the thickness of the bonding interface layer can be kept consistent, but the overall adhesion is low. This will affect the installation reliability under high-speed blade operation and easily lead to the risk of detachment.

[0010] In summary, how to prepare a blade leading edge protective cover that has stable adhesion and can ensure the excellent performance of wind turbine blades is an urgent problem to be solved. Summary of the Invention

[0011] To address the aforementioned problems, this invention provides a highly reliable installation method for a leading edge protective cover on wind turbine blades. This method avoids issues such as uneven adhesive layer thickness during the pasting of the leading edge protective cover, improves the bonding strength between the leading edge protective cover and the wind turbine blade, and simultaneously reduces costs and manufacturing complexity.

[0012] To achieve the above objectives, the present invention proposes the following technical solution: a leading edge protective cover for a wind turbine blade, wherein the leading edge protective cover is formed by stacking multiple protective cover segments longitudinally from the blade tip to the blade root to form a pre-formed protective cover, and then installing the pre-formed protective cover onto the blade; the protective cover segments are made of highly elastic material and the cross-section of the protective cover segments is U-shaped; the stacking method of adjacent protective cover segments is front-to-back overlapping or front-to-back splicing.

[0013] Preferably, the protective cover section includes a central cover section and edge cover sections located on both sides of the central cover section. The thickness of the central cover section is greater than the thickness of the edge cover sections and the thickness of the central cover section is ≥1.5mm, while the thickness of the edge cover section 4 is ≤1.5mm.

[0014] Preferably, the overlap width of adjacent protective cover sections is 10±3mm; the length of each protective cover section is ≤10m.

[0015] A highly reliable method for installing a leading-edge shield on a wind turbine blade, comprising the following steps:

[0016] S1: Roughen the leading edge surface of the blade blank;

[0017] S2: After impregnating the cut fiberglass cloth with resin, lay it onto the leading edge surface of the blade blank.

[0018] S3: Place the inside of the pre-formed protective cover against the fiberglass cloth;

[0019] S4: Lay out auxiliary vacuum material and heat-cur it around the perimeter of the preformed protective cover;

[0020] S5: After curing, remove the vacuum material and apply putty and paint around the pre-formed protective cover to produce the final leading edge protective cover product.

[0021] Preferably, in S2, the fiberglass cloth is impregnated with a low-viscosity resin, and the flow time of the low-viscosity resin in the fiberglass cloth is ≥30 min.

[0022] Preferably, the fiberglass cloth cut in S2 is larger than the preformed protective cover in both length and width directions; let the length and width of the fiberglass cloth be L1 and W1 respectively, and the length and width of the preformed protective cover be L2 and W2 respectively, then 105% L2≤L1≤110% L2, 105% W2≤W1≤110% W2.

[0023] Preferably, in S2, the cut and impregnated fiberglass cloth is laid longitudinally along the leading edge of the blade onto the leading edge surface of the blade.

[0024] Preferably, in S4, when laying auxiliary vacuuming materials around the preformed protective cover, the sealing strips, release cloth, guide net, and vacuum bag film are laid and fixed in sequence first. After the vacuuming system is built, the vacuuming and pressure holding operation is then performed.

[0025] Preferably, during the vacuuming and pressure holding operation in S4, the bonding material is heated and cured simultaneously.

[0026] Preferably, during the vacuuming and pressure holding operation in S4, the vacuum degree is ≥0.085MPa and the vacuuming time is 1-4h; when heating and curing the bonding material, a heating blanket is covered on the surface of the preformed protective cover and the heating is turned on, the heating temperature is 60℃-80℃ and the heating time is 2-5h.

[0027] The beneficial effects of this invention are:

[0028] 1. This invention first involves stacking multiple protective cover segments longitudinally from the blade tip to the blade root to form a pre-formed protective cover, and then installing the pre-formed protective cover onto the blade to form a leading edge protective cover. This segmented bonding method reduces the length of each protective cover segment. By using fiberglass reinforced resin material as the bonding layer: 1) the thickness of the bonding layer can be limited, thereby overcoming the problem of uneven adhesive layer thickness and random height variations on the outer surface of the protective cover caused by the use of pure resin or sealant in existing technologies; 2) this process can improve the bonding strength between the leading edge protective cover and the wind turbine blade; 3) when replacing the protective cover on-site, only the damaged protective cover segments can be replaced, reducing the replacement length, lowering costs, and reducing construction difficulty.

[0029] 2. In this invention, glass fiber reinforced resin material is used as the bonding layer, and the leading edge shield is tightly adsorbed onto the leading edge surface of the blade by vacuuming. This process has high bonding strength and good fit of the leading edge shield, thereby further reducing the risk of the leading edge shield falling off during use.

[0030] 3. The present invention completes the installation of the leading edge protective cover during the blade manufacturing stage. Compared with the current industry practice (that is, the protective cover is installed after painting, and pressure-sensitive adhesive is used as a common bonding solution), the entire process of the present invention is simple and the construction process is simple and efficient. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the preformed protective cover provided in Embodiment 1 of the present invention.

[0032] Figure 2 This is a cross-sectional schematic diagram of the preformed protective cover provided in Embodiment 1 of the present invention.

[0033] Figure 3 This is a schematic diagram of the overlapping of adjacent protective shield segments provided in Embodiment 1 of the present invention.

[0034] Figure 4 This is a schematic diagram of the blade leading edge surface after roughening, as provided in Embodiment 1 of the present invention.

[0035] Figure 5 This is a schematic diagram of the impregnated fiberglass cloth being attached to the leading edge of the blade, as provided in Embodiment 1 of the present invention.

[0036] Figure 6 This is a schematic diagram of the inner side of the leading edge protective cover of Embodiment 1 of the present invention being attached to the impregnated fiberglass cloth.

[0037] Figure 7 This is a schematic diagram of the blade structure during vacuuming and heating curing provided in Embodiment 1 of the present invention.

[0038] Figure 8 This is a schematic diagram of the processed leading edge protective cover product provided in Embodiment 1 of the present invention.

[0039] Figure 9 This is a schematic diagram of the overlapping of adjacent protective shield segments provided in Embodiment 2 of the present invention.

[0040] Reference numerals: 1. Protective cover section; 2. Pre-formed protective cover; 3. Central cover section; 4. Edge cover section; 5. Fiberglass cloth; 6. Blade; 7. Vacuum device. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the following description is provided in conjunction with the appendix. Figure 1-9 The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and do not constitute a limitation thereof. Example 1

[0042] A leading edge shield for a wind turbine blade is provided. The leading edge shield is formed by sequentially stacking multiple shield segments 1 longitudinally from the blade tip to the blade root to form a pre-formed shield 2, which is then installed onto the blade 6. The stacking method of adjacent shield segments 1 is as follows: Figure 3 The overlapping method shown is such that, in adjacent protective cover sections 1, the latter protective cover section 1 shown at point b overlaps the lower end of the former protective cover section 1 shown at point a. The overlap width between adjacent protective cover sections 1 is 10±3mm. The overlap of adjacent protective cover sections 1 is as follows: Figure 3 As shown in D; the length of each protective cover section 1 is ≤10m, preferably 5mm.

[0043] The protective cover section 1 is made of a highly elastic material, such as rubber or polyurethane, preferably a polyurethane-modified material. The cross-section of the protective cover section 1 is U-shaped as shown in Figure 2, specifically including a central cover section 3 and edge cover sections 4 located on both sides of the central cover section 3. The thickness of the central cover section 3 is greater than the thickness of the edge cover sections 4 to improve the bonding strength when adjacent protective cover sections 1 overlap. Specifically, the thickness of the central cover section 3 is ≥1.5mm, and the thickness of the edge cover sections 4 is ≤1.5mm.

[0044] A highly reliable method for installing a leading-edge shield on a wind turbine blade, comprising the following steps:

[0045] S1: As Figure 4 As shown, the leading edge surface of the blade 6 blank is roughened by grinding.

[0046] S2: As Figure 5 As shown, the cut fiberglass cloth 5 is impregnated with resin and then laid onto the leading edge surface of the blade 6 blank. The fiberglass cloth 5 is impregnated with a low-viscosity resin, and the flow time of the low-viscosity resin in the fiberglass cloth 5 is ≥30min. The high-viscosity resin is epoxy resin or polyurethane resin with good impregnation properties for fiberglass. The cut fiberglass cloth 5 is larger than the preformed protective cover 2 in both length and width directions. Let the length and width of the fiberglass cloth 5 be L1 and W1, respectively, to avoid shrinkage of the fiberglass cloth after glue injection, which would affect the product quality. Specifically, the length and width of the preformed protective cover 2 are L2 and W2, respectively. Then, 105% L2≤L1≤110% L2 and 105% W2≤W1≤110% W2. The cut and impregnated fiberglass cloth 5 is laid longitudinally along the leading edge of the blade 6 onto the leading edge surface of the blade 6.

[0047] S3: As Figure 6 As shown, the inner side of the preformed protective cover 2 is attached to the fiberglass cloth 5;

[0048] S4: As Figure 7As shown, auxiliary vacuuming materials are laid and heated to cure around the preformed protective cover 2. When laying auxiliary vacuuming materials around the preformed protective cover 2, the sealing strips, release cloth, guide net, and vacuum bag film are laid and fixed in sequence. After the vacuuming system is built, the vacuuming and pressure holding operation is performed. At the same time as the vacuuming and pressure holding operation, the bonding material is heated to cure. When performing the vacuuming and pressure holding operation, the vacuum degree is ≥0.085MPa, and the vacuuming time is 1-4h. When heating and curing the bonding material, a heating blanket is covered on the surface of the preformed protective cover 2 and the heating is turned on. The heating temperature is 60℃-80℃, and the heating time is 2-5h.

[0049] S5: After curing, remove the vacuum material and apply putty and paint around the pre-formed protective cover 2 to complete the process. Figure 8 The final leading edge shield product shown. Example 2

[0050] The difference between this embodiment and Embodiment 1 is that, as Figure 9 As shown, the overlapping method of adjacent protective cover segments 1 is front-to-back and top-to-bottom splicing, that is, the next protective cover segment 1 shown at b is spliced ​​on the previous protective cover segment 1 shown at a; specifically, the previous protective cover segment 1 includes a concave groove 1 shown at i and an convex boss 1 shown at j at the overlapping point D, and the next protective cover segment 1 includes a convex boss 2 shown at h and an upper concave groove 2 shown at k at the overlapping point D. The boss 2 is spliced ​​in the groove 1, and the boss 1 is spliced ​​in the groove 2, thereby realizing the overlapping of adjacent protective cover segments 1 and forming a pre-formed protective cover 2.

[0051] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0052] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A highly reliable installation method for a leading edge protective cover for wind turbine blades, characterized in that, Includes the following steps: S1: Roughen the leading edge surface of the blade (6) blank; S2: After impregnating the cut fiberglass cloth (5) with resin, lay it on the leading edge surface of the blade (6) blank; in S2, the fiberglass cloth (5) is impregnated with low viscosity resin, and the flow time of the low viscosity resin in the fiberglass cloth (5) is ≥30min. S3: Place the inner side of the preformed protective cover (2) against the fiberglass cloth (5); S4: Lay out auxiliary vacuum material and heat and cure it around the preformed protective cover (2); S5: After curing, remove the vacuum material and apply putty and paint around the pre-formed protective cover (2) to make the final leading edge protective cover product; The leading edge protective cover is formed by stacking multiple protective cover segments (1) longitudinally from the blade tip to the blade root to form a pre-formed protective cover (2), and then installing the pre-formed protective cover (2) onto the blade (6); the protective cover segment (1) is made of a highly elastic material and the cross-section of the protective cover segment (1) is U-shaped; the stacking method of adjacent protective cover segments (1) is front-to-back top-to-bottom overlap or front-to-back top-to-bottom splicing; the stacking width of adjacent protective cover segments (1) is 10±3mm; the length of each protective cover segment (1) is ≤10m; The protective cover section (1) includes a central cover section (3) and edge cover sections (4) located on both sides of the central cover section (3). The thickness of the central cover section (3) is greater than the thickness of the edge cover section (4), and the thickness of the central cover section (3) is ≥1.5mm, while the thickness of the edge cover section (4) is ≤1.5mm. The fiberglass cloth (5) cut in S2 is larger than the preformed protective cover (2) in both length and width directions; let the length and width of the fiberglass cloth (5) be L1 and W1 respectively, and the length and width of the preformed protective cover (2) be L2 and W2 respectively, then 105% L2≤L1≤110% L2, 105% W2≤W1≤110% W2.

2. The high-reliability installation method for the leading edge protective cover of a wind turbine blade according to claim 1, characterized in that, The cut and impregnated fiberglass cloth (5) in S2 is laid longitudinally along the leading edge of the blade (6) onto the leading edge surface of the blade (6).

3. The high-reliability installation method for the leading edge protective cover of wind turbine blades according to claim 2, characterized in that, When laying auxiliary vacuuming materials around the preformed protective cover (2) in S4, the sealing strip, release cloth, guide net and vacuum bag film are laid and fixed in sequence. After the vacuuming system is built, the vacuuming and pressure holding operation is carried out.

4. The high-reliability installation method for the leading edge protective cover of a wind turbine blade according to claim 3, characterized in that, While performing vacuuming and pressure holding in S4, the bonding material is heated and cured.

5. The high-reliability installation method for the leading edge protective cover of a wind turbine blade according to claim 4, characterized in that, When performing vacuuming and pressure holding operation in S4, the vacuum degree is ≥0.085MPa and the vacuuming time is 1-4h; when heating and curing the bonding material, cover the surface of the preformed protective cover (2) with a heating blanket and turn on the heating, the heating temperature is 60℃-80℃ and the heating time is 2-5h.

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