Electric heating film for wind turbine blades, electric heating system for wind turbine blades and its preparation method

Abstract

This disclosure relates to an electric heating film for wind turbine blades, an electric heating system for wind turbine blades, and a method for preparing the same. The electric heating film for wind turbine blades is suitable for being laid between a first position and a second position on a wind turbine blade and includes an electric heating layer, a protective layer, a release film layer, and an injection layer. The electric heating layer, the protective layer, the release film layer, and the injection layer are sequentially fixed together. The first position is located 5 meters from the tip of the wind turbine blade; the second position is located at the position of the maximum chord length of the windward side of the wind turbine blade. This electric heating film for wind turbine blades has a simple structure and helps to solve the problem of the difficulty in implementing de-icing technology upgrades for existing wind turbine blades.

Description

Technical Field

[0001] This disclosure relates to the field of wind turbine power generation technology, specifically to an electric heating film for wind turbine blades, an electric heating system for wind turbine blades, and a method for preparing the same. Background Technology

[0002] Operating wind turbine blades with ice significantly reduces the output power of wind power generation equipment. Furthermore, the non-uniform load on the blades can damage the equipment, affecting the safe operation of the power system. During the de-icing process, the blades may experience ice shedding, potentially endangering the safety of workers. Currently, electrothermal de-icing is commonly used to heat the surface of the blades. While this method is highly efficient, it often requires pre-installation at the factory or removal of existing blades for modification. This is not only complex but also unsuitable for the de-icing needs of existing wind turbines in high-altitude and mountainous areas. Summary of the Invention

[0003] The purpose of this disclosure is to provide an electric heating film for wind turbine blades, which has a simple structure and helps to solve the problem of the difficulty in implementing de-icing technology upgrades for existing wind turbine blades.

[0004] To achieve the above objectives, this disclosure provides an electric heating film for wind turbine blades. The electric heating film is suitable for being laid between a first position and a second position on a wind turbine blade and includes an electric heating layer, a protective layer, a release film layer, and an injection layer. The electric heating layer, the protective layer, the release film layer, and the injection layer are sequentially connected together. The first position is a position 5m away from the tip of the wind turbine blade; the second position is the position where the maximum chord length of the windward side of the wind turbine blade is located.

[0005] Optionally, the length of the electrothermal layer is 1.25-15m, the width is 1-3m, and the thickness is 1-200μm; and / or, the length of the protective layer is 1.5-17.5m, the width is 1-3m, and the thickness is 1-400μm; and / or, the length of the release layer is 1.5-17.5m, the width is 1.1-3.2m, and the thickness is 1-900μm; and / or, the length of the infusion layer is 1.5-17.5m, the width is 1.1-3.2m, and the thickness is 0.5-2cm.

[0006] Optionally, the heating layer, the protective layer, the release layer, and the filling layer are sewn together by a first seam and a second seam, wherein the distance between the first seam and the edge of the electric heating film of the fan blade is 0.3-1m, and the distance between the second seam and the edge of the electric heating film of the fan blade is 0.6-2m.

[0007] Optionally, the heating layer is made of carbon fiber cloth or graphene cloth; and / or, the protective layer is made of glass fiber cloth or ceramic fiber cloth; and / or, the release layer is made of polyamide fiber cloth, polyester fiber cloth, or polyacrylonitrile fiber cloth.

[0008] Optionally, the injection layer includes a flow guiding mesh layer and a glue injection tube layer. The glue injection tube layer is laid on the surface of the flow guiding mesh layer and includes multiple glue injection tubes. The multiple glue injection tubes are evenly spaced along the length of the electric heating film of the fan blade. Each glue injection tube has a glue inlet at one end in the axial direction and a glue outlet at the other end. The glue outlet is located in the glue injection tube layer, and the glue inlet is located on the outside of the electric heating film of the fan blade.

[0009] Based on the above scheme, this disclosure also provides a method for preparing an electric heating system for wind turbine blades. The method includes: defining an electric heating area on the wind turbine blade and grinding the electric heating area; sequentially sealing and fixing multiple of the above-mentioned wind turbine blade electric heating films in the length / width direction of the ground electric heating area, wherein the electric heating layer of each wind turbine blade electric heating film is tightly attached to the electric heating area; sealing and fixing a vacuum film on the outside of the wind turbine blade electric heating film; curing the electric heating layer and protective layer of each wind turbine blade electric heating film onto the electric heating area by vacuum infusion; removing the release layer, the infusion layer and the vacuum film; wherein the vacuum infusion adhesive used in the preparation method includes at least resin and photothermal conversion material.

[0010] Optionally, the photothermal conversion material is a two-dimensional layered material and includes graphene / graphene oxide / silicene / titanium nitride / boron nitride / titanium oxide / tungsten oxide / manganese oxide; and / or, the resin is epoxy resin, fluorosilicone resin, or fluorocarbon resin.

[0011] Optionally, the electrothermal layer and the protective layer are cured in the electrothermal region by vacuum infusion, and the curing time is 6-20 hours.

[0012] Optionally, the polishing thickness of the electrically heated area is greater than the sum of the thickness of the electrically heated layer and the thickness of the protective layer.

[0013] Based on the above solution, this disclosure also provides a wind turbine blade electric heating system, which is manufactured using the above method.

[0014] Through the above technical solution, the electric heating film for wind turbine blades provided in this disclosure can be laid on wind turbine blades. This allows for the application of the electric heating film to existing wind turbine blades, using the film to heat the blade surface for de-icing, significantly shortening high-altitude operation time and improving the construction stability of the electrothermal upgrade. Furthermore, the electric heating film is laid between the first and second positions on the wind turbine blade, specifically between a position 5 meters from the blade tip and the location of the maximum chord length of the windward side of the blade. This results in better heating of the wind turbine blades while maintaining the required heating effect and consistent film size, thus reducing costs. The wind turbine blade electric heating film comprises an electric heating layer, a protective layer, a release layer, and an injection layer connected in sequence. This makes the wind turbine blade electric heating film a single, integrated film with a simple structure. The electric heating layer heats the surface of the wind turbine blade to remove ice. The protective layer protects the electric heating layer from damage. The injection and release layers utilize a vacuum injection process to fix the wind turbine blade electric heating film to the surface of the wind turbine blade and remove the injection and film layers. This addresses the difficulty of implementing de-icing modifications for existing wind turbine blades. For example, the injection layer can be connected to an external injection container, allowing the injection medium from the external container to be transported from the ground to the injection layer of the wind turbine blade at high altitude via pipelines. After the injection medium solidifies, the injection layer, release layer, protective layer, and electric heating layer are fixed to the wind turbine blade. The release layer separates from the protective layer by detaching itself. Therefore, the electric heating film structure for wind turbine blades provided in this disclosure is simple and helps to solve the problem of the difficulty in implementing de-icing technology upgrades for existing wind turbine blades.

[0015] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of the structure of the electric heating film for wind turbine blades provided according to some embodiments of this disclosure;

[0018] Figure 2 This is a schematic diagram of the structure of a wind turbine blade in a method for preparing a wind turbine blade electric heating system according to some embodiments of the present disclosure, wherein the wind turbine blade electric heating film is shown;

[0019] Figure 3 This is a flowchart of a method for preparing an electric heating system for wind turbine blades according to some embodiments of the present disclosure.

[0020] Explanation of reference numerals in the attached figures

[0021] 1-Electric heating film for fan blades; 11-Electric heating layer; 12-Protective layer; 13-Removal layer; 14-Injection layer; 10-Fan blades. Detailed Implementation

[0022] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0023] In this disclosure, unless otherwise stated, the directional terms "inner" and "outer" refer to "inner" and "outer" relative to the contour of the corresponding component itself. Furthermore, the use of terms such as "first" and "second" is intended to distinguish different components and does not imply sequentiality or importance. Additionally, in the following description, when referring to the accompanying drawings, the same reference numerals in different drawings denote the same elements. Those skilled in the art should understand that the above definitions are for explanation and illustration only and should not be construed as limiting the scope of this disclosure.

[0024] According to some embodiments of this disclosure, an electric heating film for wind turbine blades is provided. Figure 1 An embodiment of the electric heating film for the wind turbine blades is shown. (Reference) Figure 1 As shown, the electric heating film 1 of the wind turbine blade is suitable for being laid between the first position and the second position of the wind turbine blade 10 and includes an electric heating layer 11, a protective layer 12, a release film layer 13 and an injection layer 14. The electric heating layer 11, the protective layer 12, the release film layer 13 and the injection layer 14 are connected together in sequence. The first position is a position 5m away from the tip of the wind turbine blade 10; the second position is the position where the maximum chord length of the windward surface of the wind turbine blade 10 is located.

[0025] Through the above technical solution, the electric heating film for wind turbine blades provided in this disclosure can be laid on the wind turbine blades 10. This allows for the defrosting of existing wind turbine blades by laying the electric heating film 1 on them and using it to heat the surface of the wind turbine blades 10, significantly shortening high-altitude operation time and improving the construction stability of the electrothermal upgrade. Furthermore, the electric heating film is laid between the first and second positions of the wind turbine blades 10, specifically between a position 5m from the blade tip and the position of the maximum chord length of the windward side of the wind turbine blades 10. This results in better heating of the wind turbine blades 10, while also ensuring the required heating effect and maintaining the appropriate size of the electric heating film, thus helping to reduce costs. The wind turbine blade electric heating film 1 comprises an electric heating layer 11, a protective layer 12, a release layer 13, and an injection layer 14 connected in sequence. That is, the wind turbine blade electric heating film 1 is an integral film with a simple structure. The electric heating layer 11 heats the surface of the wind turbine blade 10 to remove ice from its surface. The protective layer 12 protects the electric heating layer 11 from damage. The injection layer 14 and the release layer 13 are installed using a vacuum injection process to fix the wind turbine blade electric heating film 1 onto the surface of the wind turbine blade 10. Removing the injection layer 14 and the film layer helps solve the problem of the difficulty in implementing de-icing technology upgrades for existing wind turbine blades. For example, the injection layer 14 can be connected to an external injection container, allowing the injection medium in the external injection container to be transported from the ground to the injection layer 14 of the wind turbine blade 10 at high altitude through pipelines. After the injection medium solidifies, the injection layer 14, the release film layer 13, the protective layer 12, and the electrothermal layer 11 are fixed to the wind turbine blade 10. The release film layer 13 can detach itself from the protective layer 12, thus separating the injection layer 14 from the protective layer 12. Therefore, the electric heating film structure for wind turbine blades provided in this disclosure is simple and helps solve the problem of the difficulty in implementing de-icing technology upgrades for existing wind turbine blades.

[0026] It should be noted that when the electric heating film 1 for the wind turbine blades is laid, the electric heating layer 11 should be understood as being located on the side closest to the surface of the wind turbine blade 10 and directly laid on the surface of the wind turbine blade 10, while the injection layer 14 should be understood as being located on the side away from the surface of the wind turbine blade 10. Furthermore, the sequential connection of the electric heating layer 11, protective layer 12, release layer 13, and injection layer 14 should be understood as the electric heating layer 11, protective layer 12, release layer 13, and injection layer 14 of the electric heating film 1 for the wind turbine blades being connected together by means of bonding, sewing, etc., and the release layer 13 and injection layer 14 being detachable from the electric heating layer 11 and protective layer 12.

[0027] In some embodiments of this disclosure, the electrothermal layer 11, protective layer 12, release layer 13, and infusion layer 14 can be configured in any suitable manner. Optionally, the length of the electrothermal layer 11 is 1.25-15m, the width is 1-3m, and the thickness is 1-200μm; and / or, the length of the protective layer 12 is 1.5-17.5m, the width is 1-3m, and the thickness is 1-400μm; and / or, the length of the release layer 13 is 1.5-17.5m, the width is 1.1-3.2m, and the thickness is 1-900μm; and / or, the length of the infusion layer 14 is 1.5-17.5m, the width is 1.1-3.2m, and the thickness is 0.5-2cm. The length of the heating layer 11 can be any value between 1.25 and 15 m, such as 2 m, 5 m, 7 m, 9 m, 11 m, 15 m, etc.; the width of the heating layer 11 can be any value between 1 and 3 m, such as 1.5 m, 2 m, 2.5 m, etc.; and the thickness of the heating layer 11 can be any value between 1 and 200 μm, such as 15 μm, 50 μm, 74 μm, 120 μm, etc. Similarly, the length of the protective layer 12 can be any value between 1.5 and 17.5 m, the width of the protective layer 12 can be any value between 1 and 3 m, and the thickness of the protective layer 12 can be any value between 1 and 400 μm; the length of the release layer 13 can be any value between 1.5 and 17.5 m, the width of the infusion layer 14 can be any value between 1.1 and 3.2 m, and the thickness of the infusion layer 14 can be any value between 1 and 900 μm; the length of the infusion layer 14 can be any value between 1.5 and 17.5 m, the width of the infusion layer 14 can be any value between 1.1 and 3.2 m, and the thickness of the infusion layer 14 can be any value between 0.5 and 2 cm. It should be understood that the length, width, and thickness of the heating layer 11, protective layer 12, demolding layer 13, and injection layer 14 are determined according to the size of the fan blade 10. In some embodiments of this disclosure, the length and width of the heating layer 11 and protective layer 12 can be the same, and the length and width of the demolding layer 13 and injection layer 14 can be the same. In order to ensure smooth demolding, the length of the injection layer 14 and demolding layer 13 is 0.1-0.2m longer than the length of the heating layer 11 / protective layer 12, or the width of the injection layer 14 and demolding layer 13 is 0.1-0.2m longer than the width of the heating layer 11 / protective layer 12. This disclosure does not impose any restrictions on these aspects, and those skilled in the art can make adaptive choices according to actual needs.

[0028] Additionally, the heating layer 11 can be made of carbon fiber cloth or graphene cloth; and / or, the protective layer 12 can be made of glass fiber cloth or ceramic fiber cloth; and / or, the release layer 13 can be made of polyamide fiber cloth, polyester fiber cloth, or polyacrylonitrile fiber cloth. In some embodiments of this disclosure, the heating layer 11 is made of carbon fiber cloth, for example, biaxial carbon fiber cloth. The protective layer 12 is made of glass fiber cloth, for example, biaxial glass fiber cloth. The release layer 13 is made of polyamide fiber cloth. It should be noted that the heating layer 11, the protective layer 12, and the release layer 13 can also be made of other materials, and this disclosure does not impose any limitations on them.

[0029] In addition, refer to Figure 1 As shown, the injection layer 14 may include a guide net layer (not shown) and an injection pipe layer (not shown). The injection pipe layer is laid on the surface of the guide net layer and includes multiple injection pipes (not shown). The multiple injection pipes are evenly spaced along the length of the electric heating film 1 of the fan blade. Each injection pipe has an inlet (not shown) at one end in the axial direction and an outlet (not shown) at the other end. The outlet is located in the injection pipe layer, and the inlet is located on the outside of the electric heating film 1 of the fan blade. The injection pipes facilitate the delivery of the injection medium from an external injection container on the ground to the injection layer 14 of the fan blade 10 at high altitude, thereby greatly shortening the high-altitude operation time and improving the construction stability of the electric heating technology upgrade. The even spacing of the multiple injection pipes facilitates the improvement of injection efficiency and uniformity, further shortening the high-altitude operation time and improving the construction stability of the electric heating technology upgrade. The flow guiding mesh layer includes a flow guiding mesh (not shown in the figure). The flow guiding mesh facilitates the guidance and delivery of the injection medium from the dispensing port, thereby enabling the injection medium to flow quickly and evenly onto the entire electric heating film 1 of the fan blade. To ensure smooth demolding, the length of the flow guiding mesh is 3 cm less than the length of the electric heating layer 11 / protective layer 12, or the width of the flow guiding mesh is 3 cm less than the width of the electric heating layer 11 / protective layer 12. The flow guiding mesh and the injection tube can be configured in any suitable way. Optionally, the flow guiding mesh is constructed as a polyamide flow guiding mesh, and the injection tube is constructed as a vacuum-injection spiral resin tube with a quantity of 3. The 3 injection tubes are respectively set at four equal points along the length of the electric heating film 1 of the fan blade. The diameter of each injection tube can be 3 cm, and the length of each injection tube can be designed according to actual needs. For example, the length of each injection tube needs to be greater than the height from the dispensing port to the ground. During injection, an external injection container can use an injection pump to deliver the injection medium from the inlet to the outlet of the injection tube.

[0030] In other embodiments of this disclosure, the electrothermal layer 11, the protective layer 12, the release layer 13, and the infusion layer 14 may be configured in other ways, and this disclosure does not impose any restrictions on them.

[0031] In some embodiments of this disclosure, reference is made to Figure 1 As shown, the heating layer 11, protective layer 12, release layer 13, and filling layer 14 can be sewn together by a first seam (not shown) and a second seam (not shown). The distance between the first seam and the edge of the electric heating film 1 of the fan blade is 0.3-1m, and the distance between the second seam and the edge of the electric heating film 1 of the fan blade is 0.6-2m. The distances between the first seam, the second seam, and the edge of the electric heating film 1 of the fan blade can be selectively designed according to actual needs. For example, the distance between the first seam and the edge of the electric heating film 1 of the fan blade can be 0.5m, and the distance between the second seam and the edge of the electric heating film 1 of the fan blade can be 0.8m. This disclosure does not impose any limitations on this. Furthermore, the sewing of the heating layer 11, protective layer 12, release layer 13, and filling layer 14 together by the first seam and the second seam should be understood as each edge of the heating layer 11, protective layer 12, release layer 13, and filling layer 14 being sewn together by the first seam and the second seam.

[0032] Based on the above solutions, this disclosure also provides a method for preparing an electric heating system for wind turbine blades. Figure 3 A flowchart of the preparation method is shown, for reference. Figure 3 As shown, the preparation method includes:

[0033] Step S101: Determine the electric heating area on the fan blade 10 and grind the electric heating area.

[0034] Step S102: Seal and fix multiple of the above-mentioned fan blade electric heating films 1 in the length direction of the electric heating area after polishing, wherein the electric heating layer 11 of each fan blade electric heating film 1 is tightly attached to the electric heating area.

[0035] Step S103: Seal and fix the vacuum film on the outside of the electric heating film 1 of each fan blade;

[0036] Step S104: The electric heating layer 11 and the protective layer 12 of the electric heating film 1 of each wind turbine blade are solidified in the electric heating area by vacuum infusion.

[0037] Step S105: Remove the stripping layer 13, the infusion layer 14, and the vacuum membrane.

[0038] The vacuum infusion adhesive used in the preparation method includes at least resin and photothermal conversion material.

[0039] Through the above technical solution, in the preparation method of the wind turbine blade electric heating system provided in this disclosure, firstly, an electric heating area is determined on the in-service wind turbine blade or other wind turbine blade. The electric heating area is located between the first and second positions of the wind turbine blade 10, that is, between the blade tip 5m away from the maximum chord length of the windward side of the wind turbine blade 10. Then, the determined electric heating area is polished and cleaned after polishing. Afterward, multiple wind turbine blade electric heating films 1 are sequentially sealed and fixed along the length direction of the polished electric heating area, and each electric heating layer 11 is tightly attached to the electric heating area. Next, a vacuum film is sealed and fixed on the outside of each wind turbine blade electric heating film 1, and the electric heating layer 11 and the protective layer 12 of each wind turbine blade electric heating film 1 are cured in the electric heating area by vacuum infusion. The vacuum infusion medium is resin and photothermal conversion material. Among them, the photothermal conversion material can effectively absorb light energy and increase the curing temperature of the resin, thereby improving the work efficiency of high-altitude technical modification of wind turbine blades. Finally, the release layer 13, the infusion layer 14, and the vacuum film are removed. This method for preparing the electric heating system for wind turbine blades allows for the addition of an electric heating layer 11 and a protective layer 12 to the surface of the blades without compromising their aerodynamic performance. It effectively removes ice during winter icing, and is simple, convenient, and efficient to operate. Furthermore, this method is more suitable for the technical upgrades of existing wind turbine units operating at low temperatures and high altitudes. Therefore, it effectively solves the problems of difficult implementation of technical upgrades for existing wind turbine blades and the difficulty in effectively disassembling, assembling, and operating existing wind turbine blades in mountainous areas. It also effectively ensures the accuracy and efficiency of technical upgrades for existing wind turbine blades.

[0040] In step S101, the electrically heated area can be polished manually or electrically using tools such as sandpaper and cleaned. Polishing is done from top to bottom. When using an electric polisher with sandpaper, the sandpaper grit can be 80-1200 grit, or more specifically, 120-240 grit. For example, if the sandpaper grit is 120 grit, the speed of the electric polisher is 200-1500 r / min, or more specifically, 600-900 r / min, or for example, 800 r / min. In addition, in step S101, the grinding thickness of the electric heating area is greater than the sum of the thickness of the electric heating layer 11 and the thickness of the protective layer 12, so as to facilitate the laying of the electric heating layer 11 and the post-laying treatment, thereby ensuring the flatness of the surface of the fan blade 10. Furthermore, the grinding thickness of the electric heating area should be 50 μm greater than the sum of the thickness of the electric heating layer 11 and the thickness of the protective layer 12. This disclosure does not impose any limitations on this.

[0041] In step S102, each fan blade electric heating film 1 is fixed to the electric heating area by adhesive strip bonding and strapping. Each fan blade electric heating film 1 is first bonded to the electric heating area with sealing adhesive strips, the bonding range of which is 5cm from the edge of the release layer 13. Then, strapping is applied to each fan blade electric heating film 1 to further fix it to the fan blade 10. For example, four equally spaced strappings are used, one strap at each end of the length direction of each fan blade electric heating film 1, and another strap at one-third and two-thirds of the length direction of each fan blade electric heating film 1. It is also understood that in some embodiments of this disclosure, multiple fan blade electric heating films 1 are arranged sequentially along the length direction of the electric heating area. These multiple fan blade electric heating films 1 can be spaced apart or closely arranged along the length direction of the electric heating area. (Refer to...) Figure 2 As shown, four fan blade electric heating films 1 are sequentially arranged along the length of the electric heating area. These four fan blade electric heating films 1 are closely arranged along the length of the electric heating area, which makes construction convenient and quick and helps to shorten the construction period.

[0042] In step S103, a vacuum film is laid from top to bottom on the outer surface of each fan blade electric heating film 1 laid in step S102 using sealing tape. That is, a vacuum film is laid on the surface of each fan blade electric heating film 1 near the injection layer 14. After the vacuum film is laid, a vacuum pump is used to evacuate the system and test the system's sealing performance under pressure. For example, a vacuum gauge is used to fix the suction port of the suction pipe and seal the air inlet. Then, the vacuum pump is turned on, and the vacuum system pressure is reduced to below 20-4 mbar. The vacuum pump is then turned off, and the pressure is maintained for 10-30 minutes before testing the pressure. If the pressure increase does not exceed 5-10 mbar, the vacuum test is passed, and the next injection process can proceed. Further, during the vacuum test, the vacuum system pressure can be reduced to below 25 mbar, and the pressure is maintained for 15 minutes before testing the system pressure. If the pressure increase does not exceed 5 mbar, the vacuum test is passed. If the vacuum test fails, the vacuum system needs to be leak-tested until there are no leaks and the above requirements are met. The vacuum membrane can be constructed as a special nylon vacuum membrane for wind turbine blades and has an air extraction port. The air extraction port is located in the middle of the lower edge of the vacuum membrane and can be 5cm in diameter. The thickness of the vacuum membrane is 3mm and the width is 1.2~3.2m, and further, the width is 2.1m.

[0043] In step S104, resin and photothermal conversion material are continuously injected into each injection tube, and a vacuum is continuously drawn from the bottom of the vacuum membrane until the resin and photothermal conversion material uniformly penetrate the surface of the electric heating film 1 and the fan blade 10. After injection, wait 6-20 hours for the resin and photothermal conversion material to cure, thereby curing the electric heating layer 11 and protective layer 12 of each fan blade electric heating film 1 in the electric heating area. The resin and photothermal conversion material need to be mixed with a curing agent in a specific ratio and stirred evenly before injection. The injection rate is 30-50 g / min, and the curing time is 6-20 hours, specifically 12 hours. Because the photothermal conversion material has high light absorption capacity, it can convert light energy into heat energy during resin curing. This expands the applicable temperature range for resin curing, shortens the curing time, thus shortening the construction period, and increases the bonding strength, thereby improving the quality of resin curing. Furthermore, when the surface of the wind turbine blade 10 is covered with ice, the photothermal conversion material can also convert light energy into heat energy through photothermal conversion to assist in heating the wind turbine blade 10 and reduce the power consumption of the electrothermal layer. In addition, the photothermal conversion material and resin can be selected adaptively according to actual needs. For example, the photothermal conversion agent material is a two-dimensional layered material including graphene / graphene oxide / silicene / titanium nitride / boron nitride / titanium oxide / tungsten oxide / manganese oxide. The photothermal conversion material is set as a two-dimensional layered material (microscopically a two-dimensional layered structure), which on the one hand can effectively reduce the viscosity of the resin and improve its fluidity, making the resin more evenly distributed during high-altitude injection; on the other hand, the two-dimensional layered material can form an isolation layer to form a natural physical barrier to prevent the wind turbine blade 10 from being invaded by corrosive media, resulting in high corrosion resistance. The resin can be epoxy resin, fluorosilicone resin, or fluorocarbon resin. This disclosure does not impose any limitations on this.

[0044] In step S105, the release layer 13, the injection layer 14, and the vacuum membrane are removed as a whole, leaving only the injection-bonded electrothermal layer 11 and the protective layer 12 on the surface of the wind turbine blade 10. After demolding, the uniformity of the injection of the electrothermal layer 11 and the protective layer 12 is checked. The blade surface needs to be manually observed. If it is flat and uniform, no repair is needed; if there are defects such as pinholes or holes, small-scale repairs and localized injection are required. After ensuring that the overall injection meets the standards, putty and topcoat are applied according to the wind turbine blade standards. To ensure the quality of the coating, roller coating is used. The topcoat can be applied after the putty has been applied and cured for 24 hours, and the topcoat will cure after 12 hours. The coating methods include, but are not limited to, brushing, roller coating, and spraying.

[0045] It should be noted that the weight increase of a single fan blade 10 after the technical modification should be controlled within 1.5%, and the weight deviation between the three blades should be controlled within 0.5%.

[0046] Based on the above solution, this disclosure also provides a wind turbine blade electric heating system, which is manufactured using the above method.

[0047] The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0048] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0049] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. An electric heating film for wind turbine blades, characterized in that, The electric heating film for the wind turbine blade is suitable for being laid between a first position and a second position of the wind turbine blade and includes an electric heating layer, a protective layer, a release film layer and an injection layer. The electric heating layer, the protective layer, the release film layer and the injection layer are sequentially connected together and sewn together by a first seam and a second seam. The injection layer includes a flow guiding mesh layer and a glue injection tube layer. The glue injection tube layer is laid on the surface of the flow guiding mesh layer. The vacuum injection medium delivered to the injection layer includes at least resin and photothermal conversion material. The first position is a location 5m away from the tip of the wind turbine blade; the second position is the location of the maximum chord length of the windward side of the wind turbine blade.

2. The electric heating film for wind turbine blades according to claim 1, characterized in that, The electrothermal layer has a length of 1.25-15m, a width of 1-3m, and a thickness of 1-200μm; and / or, The protective layer has a length of 1.5-17.5m, a width of 1-3m, and a thickness of 1-400μm; and / or, The stripping layer has a length of 1.5-17.5 m, a width of 1.1-3.2 m, and a thickness of 1-900 μm; and / or, The length of the injection layer is 1.5-17.5m, the width is 1.1-3.2m, and the thickness is 0.5-2cm.

3. The electric heating film for wind turbine blades according to claim 1, characterized in that, The distance between the first seam and the edge of the electric heating film of the fan blade is 0.3-1m, and the distance between the second seam and the edge of the electric heating film of the fan blade is 0.6-2m.

4. The electric heating film for wind turbine blades according to claim 1, characterized in that, The electrothermal layer is made of carbon fiber cloth or graphene cloth; and / or, The protective layer is made of fiberglass cloth or ceramic fiber cloth; and / or, The release layer is made of polyamide fiber cloth, polyester fiber cloth, or polyacrylonitrile fiber cloth.

5. The electric heating film for wind turbine blades according to claim 1, characterized in that, The glue injection tube layer includes multiple glue injection tubes, which are evenly spaced along the length of the electric heating film on the fan blades. Each of the glue injection tubes has a glue inlet at one end in the axial direction and a glue outlet at the other end. The glue outlet is located in the glue injection tube layer, and the glue inlet is located on the outside of the electric heating film of the fan blade.

6. A method for preparing an electric heating system for wind turbine blades, characterized in that, The preparation method includes: The electric heating area is identified on the fan blades, and the electric heating area is then polished. Multiple fan blade electric heating films according to any one of claims 1-5 are sequentially sealed and fixed along the length of the electric heating area after polishing, wherein the electric heating layer of each fan blade electric heating film is in close contact with the electric heating area. A vacuum film is sealed and fixed on the outside of the electric heating film of each of the fan blades; The electrothermal layer and protective layer of the electric heating film of each wind turbine blade are solidified in the electric heating area by vacuum infusion; Remove the release layer, the infusion layer, and the vacuum membrane. The vacuum infusion adhesive used in the preparation method includes at least resin and photothermal conversion material.

7. The method for preparing the electric heating system for wind turbine blades according to claim 6, characterized in that, The photothermal conversion material is a two-dimensional layered material and includes graphene / graphene oxide / silicene / titanium nitride / boron nitride / titanium oxide / tungsten oxide / manganese oxide; and / or, The resin is epoxy resin, fluorosilicone resin, or fluorocarbon resin.

8. The method for preparing the electric heating system for wind turbine blades according to claim 6, characterized in that, The electrothermal layer and the protective layer are cured in the electrothermal region by vacuum infusion, and the curing time is 6-20 hours.

9. The method for preparing the electric heating system for wind turbine blades according to claim 6, characterized in that, The polishing thickness of the electrically heated area is greater than the sum of the thickness of the electrically heated layer and the thickness of the protective layer.

10. An electric heating system for wind turbine blades, characterized in that, The electric heating system for the wind turbine blades is made using the method described in any one of claims 6-9.

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