Salt spray resistant cable based on aluminum alloy core for offshore wind power generation and use method of salt spray resistant cable

Abstract

The invention relates to the technical field of offshore wind power generation, in particular to an aluminum alloy core salt-fog-resistant cable for offshore wind power generation and a using method thereof.The aluminum alloy core salt-fog-resistant cable comprises a light wrapping type isolation layer, an aluminum alloy flexible conductor is installed in the light wrapping type isolation layer, and ethylene propylene diene monomer insulation is installed on the outer side of the light wrapping type isolation layer; a salt-fog-resistant and high-tear-resistant chlorinated polyethylene sheath is mounted on the outer side of the ethylene propylene diene monomer insulation layer; the aluminum alloy flexible conductor is a conductor and is prepared by adding a carbon fiber component into a fifth aluminum alloy flexible structure, and the specific formula comprises 97.5% of aluminum, 0.6% of magnesium, 0.53% of silicon, 0.3% of iron, 0.05% of copper, 0.02% of zinc and 1.0% of short carbon fibers; according to the invention, the cable has excellent flame-retardant performance, can meet a single-wire combustion test, is light in weight and low in cost, the cost of the cable is 40-60% lower than that of a cable adopting a conventional tinned copper conductor structure, the cable is light in weight and convenient to lay, and the construction cost can be greatly saved.

Description

Technical Field

[0001] The invention relates to the technical field of offshore wind power generation, in particular to an aluminum alloy core salt spray resistant cable for offshore wind power generation and a use method thereof. Background Art

[0002] Aluminum alloy core salt spray resistant cable for offshore wind power generation is a special cable designed for marine environment. It has excellent corrosion resistance, especially can resist the erosion of salt spray in marine environment. This cable usually uses aluminum alloy as the conductor material, not only because aluminum alloy has a lower density, which reduces the weight of the cable, but also its corrosion resistance and conductivity also meet the requirements of offshore wind power generation system; This type of cable is widely used in marine engineering, port terminals, offshore oil platforms and other places to ensure the stable transmission of power and signals, effectively extend the service life of the cable and reduce maintenance costs; The cable process structure for traditional wind power generation systems usually uses a second copper conductor twisted together, extruded rubber insulation and sheath, and is inspected as a finished product after continuous pipeline vulcanization. The cable with this structure has the defects of high procurement cost, heavy weight, poor bending performance, etc. Therefore, in order to solve the above problems, an aluminum alloy core salt spray resistant cable for offshore wind power generation and a method of using the same are proposed. Summary of the invention

[0003] The purpose of the present invention is to provide an aluminum alloy core salt spray resistant cable for offshore wind power generation and a method of using the same, so as to solve the problem that the cable process structure for traditional wind power generation systems usually adopts a second copper conductor twisted, extruded rubber insulation and sheath, and finished product inspection after continuous pipeline vulcanization. The cable of this structure has the defects of high procurement cost, heavy weight, poor bending performance, etc.

[0004] To achieve the above object, the present invention provides the following technical solutions: Aluminum alloy core salt spray resistant cable for offshore wind power generation and its use method, including a light wrapped insulation layer, an aluminum alloy soft conductor is installed inside the light wrapped insulation layer, EPDM rubber insulation is installed outside the light wrapped insulation layer, and a salt spray resistant and highly tear-resistant chlorinated polyethylene sheath is installed outside the EPDM rubber insulation; The aluminum alloy soft conductor is a conductor, which is made of the fifth aluminum alloy soft structure and carbon fiber components, and the specific formula includes aluminum, magnesium, silicon, iron, copper, zinc and short-cut carbon fiber, wherein aluminum accounts for 97.5%, magnesium accounts for 0.6%, silicon accounts for 0.53%, iron accounts for 0.3%, copper accounts for 0.05%, zinc accounts for 0.02% and short-cut carbon fiber accounts for 1.0%; The light wrapped isolation layer is an isolation layer, and the EPDM rubber insulation is an insulation layer.

[0005] As a further optimized content of the present invention, the production process of the aluminum alloy soft conductor is: Step 1: Mixing and smelting: Mix the aluminum substrate and various alloy elements in proportion and smelt them at a temperature of 750°C - 800°C; Step 2: Uniform dispersion of carbon fiber: During the melting process, chopped carbon fiber is gradually added, and mechanical stirring and ultrasonic dispersion technology are used to ensure uniform distribution of carbon fiber; Step 3: Ingot forming: forming aluminum alloy base material through continuous casting technology; Step 4: Multi-pass drawing: The ingot is subjected to multi-pass drawing to control the single wire diameter within the target range; Step 5: Heat treatment: Use annealing process to eliminate processing stress and optimize electrical conductivity and mechanical strength.

[0006] As a further optimization of the present invention, in said step 1, after the ingredients are smelted, they are kept warm for 15-20 minutes, and during this period, a refining agent is added to remove inclusions and gases.

[0007] As a further optimization of the present invention, in the step 2, the carbon fiber is selected from short-cut fibers, the length of which is controlled to be 3-5 mm, and the surface is coated with an epoxy resin coating.

[0008] As a further optimization of the present invention, in the continuous casting process of step three, the temperature of the aluminum liquid is controlled at 720°C - 740°C, an initial aluminum alloy ingot is formed by a water-cooled mold, the cooling rate is controlled at 5-10°C / second, and the ingot size diameter is in the range of 9 - 15 mm.

[0009] As a further optimized content of the present invention, the drawing step in step 4 is: S1: The ingot is initially rolled to form an intermediate billet with a diameter controlled at 4-5 mm; S2: Through 6-8 passes of gradual drawing, the diameter of the single wire is finally controlled within the range of 0.30-0.50 mm, and the surface is cleaned after each drawing; S3: During the drawing process, spray lubricant regularly.

[0010] As a further optimization of the present invention, in the annealing process in step five, a single monofilament is heated to 250°C - 300°C in a continuous annealing furnace for 3-5 hours, and argon gas protection annealing is used.

[0011] As a further optimized content of the present invention, the formula of the lightweight wrapped isolation layer includes polypropylene film, micron-grade aluminum oxide, nano-silicon powder, polyethylene wax, magnesium hydroxide and silane coupling agent, wherein the polypropylene film accounts for 65%, the micron-grade aluminum oxide accounts for 12%, the nano-silicon powder accounts for 8%, the polyethylene wax accounts for 5%, the magnesium hydroxide accounts for 7%, and the silane coupling agent accounts for 3%.

[0012] As a further optimized content of the present invention, the following steps are included: Step I: Installation and laying: According to the layout of the offshore wind power generation equipment, the cable is connected between the generator and the transformer through a preset laying pipeline or hanging device, and during the laying process, the bending radius of the cable is ensured to be not less than 10 times its diameter; Step II: Conductor connection: At the cable joint, use a special aluminum conductor crimping device to crimp the aluminum alloy soft conductor. After crimping, use an antioxidant protective agent to seal the joint to ensure that the resistance at the connection is no more than 1.1 times the normal conductor resistance. Step III: Salt spray resistance test: After laying, the salt spray resistant and high tear resistance chlorinated polyethylene sheath is subjected to a salt spray spray test. The concentration of the sodium chloride solution in the test environment is 5%, and the test time is 720 hours to ensure that there are no cracks or obvious corrosion on the surface of the sheath; Step IV: Regular maintenance: Check the conductor resistance, sheath integrity and insulation performance of the cable every six months.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. In the present invention, the cable has excellent flame retardant properties, can meet the single-wire combustion test, and the product is light in weight and low in cost, which is 40-60% lower than the cost of cables with conventional tinned copper conductor structures. It is light in weight and easy to lay, which can greatly save construction costs; 2. In the present invention, by selecting high-performance aluminum alloy soft conductors and carbon fiber reinforced materials, combined with precise production processes, the electrical conductivity and mechanical strength of the cable are significantly improved. The formula optimization of the aluminum alloy soft conductor and the uniform dispersion of carbon fiber enhance the toughness and fatigue resistance of the material, and improve the reliability of the cable. In addition, through the fine casting and drawing process, the dimensional consistency of the conductor is effectively controlled, ensuring efficient electrical conductivity and stable process. In the offshore wind power generation system, these optimizations not only enhance the durability of the cable, reduce the failure rate during operation, but also improve the overall stability and safety of the system; 3. In the present invention, a salt spray-resistant, highly tear-resistant chlorinated polyethylene sheath and an innovative lightweight wrapped isolation layer are used to enhance the corrosion resistance and aging resistance of the cable in the marine environment. The salt spray resistance test proves that the sheath performs well in a long-term salt spray environment, ensuring the long-term stable operation of the cable in harsh environments. Regular cable maintenance and inspection ensure the continued good state of the conductor resistance and insulation performance, further improving the reliability and service life of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 This is a production process flow chart of the aluminum alloy core salt spray resistant cable for offshore wind power generation according to the present invention; Figure 3 The present invention is a flow chart of an aluminum alloy core salt spray resistant cable for offshore wind power generation and a method of using the cable.

[0015] In the figure: 1. Aluminum alloy soft conductor; 2. Lightweight wrapped isolation layer; 3. EPDM rubber insulation; 4. Salt spray resistant and highly tear-resistant chlorinated polyethylene sheath. DETAILED DESCRIPTION

[0016] See also Figure 1-3 , the present invention provides a technical solution: An aluminum alloy core salt-spray resistant cable for offshore wind power generation and a method of using the same include a light wrapped isolation layer 2, an aluminum alloy soft conductor 1 installed inside the light wrapped isolation layer 2, an EPDM rubber insulation 3 installed outside the light wrapped isolation layer 2, and a salt-spray resistant and highly tear-resistant chlorinated polyethylene sheath 4 installed outside the EPDM rubber insulation 3; the aluminum alloy soft conductor 1 is a conductor, and is made of a fifth aluminum alloy soft structure with carbon fiber components added thereto, and the specific formula includes aluminum, magnesium, silicon, iron, copper, zinc and chopped carbon fiber, with aluminum accounting for 97.5%, magnesium accounting for 0.6%, silicon accounting for 0.53%, iron accounting for 0.3%, copper accounting for 0.05%, zinc accounting for 0.02% and chopped carbon fiber accounting for 1.0%; the light wrapped isolation layer 2 is an isolation layer, and the EPDM rubber insulation 3 is an insulation layer.

[0017] As a technical solution for further implementation of this scheme, the production process of the aluminum alloy soft conductor 1 is: Step 1: Mixing and smelting: Mix the aluminum substrate and various alloy elements in proportion and smelt them at a temperature of 750°C - 800°C to ensure uniform alloy composition, improve conductivity and material stability; Step 2: Uniform dispersion of carbon fiber: During the smelting process, chopped carbon fiber is gradually added, and mechanical stirring and ultrasonic dispersion technology are used to ensure uniform distribution of carbon fiber to enhance the mechanical strength and toughness of the material and improve reliability; Step 3: Ingot forming: Through continuous casting technology, aluminum alloy base material is formed to improve the quality of ingots, reduce material defects, and ensure subsequent processing performance; Step 4: Multi-pass drawing: The ingot is subjected to multi-pass drawing to control the diameter of the single wire within the target range, so as to accurately control the conductor size, improve the conductive efficiency and process stability; Step 5: Heat treatment: Use annealing process to eliminate processing stress, optimize conductivity and mechanical strength, reduce internal stress of the material, improve fatigue resistance and conductor durability; As a technical solution for further implementation of this scheme, after the ingredients are smelted in step 1, they are kept warm for 15-20 minutes, and refining agents are added during this period to remove inclusions and gases, improve the purity of the aluminum liquid, reduce the impurity content in the conductor, and improve the conductivity; As a technical solution for further implementation of this scheme, in step 2, the carbon fiber is selected from short-cut fibers with a length controlled at 3-5 mm, and the surface is coated with an epoxy resin coating, which can enhance the bonding force between the carbon fiber and the aluminum matrix and improve the comprehensive performance of the conductor; As a technical solution for further implementation of this solution, in step 3, during the continuous casting process, the temperature of the aluminum liquid is controlled at 720°C - 740°C, an initial aluminum alloy ingot is formed by a water-cooled mold, the cooling rate is controlled at 5-10°C / second, and the ingot size diameter is within the range of 9 - 15 mm, so as to ensure uniform crystallization of the aluminum alloy, reduce internal defects, and improve mechanical properties; As a technical solution for further implementation of this solution, the drawing step in step 4 is: S1: The ingot is initially rolled to form an intermediate billet with a diameter controlled at 4-5 mm; S2: Through 6-8 passes of gradual drawing, the diameter of the single wire is finally controlled within the range of 0.30-0.50 mm, and the surface is cleaned after each drawing; S3: During the drawing process, spray lubricant regularly to improve the surface quality and consistency of the conductor and reduce the loss during the drawing process; As a technical solution for further implementation of this solution, in the annealing process in step 5, a single single wire is heated to 250°C - 300°C in a continuous annealing furnace for 3-5 hours, and argon protection annealing is used to significantly improve the conductivity and toughness of the material and extend the service life of the conductor; As a technical solution for further implementation of this plan, the formula of the light-weight wrapped isolation layer includes polypropylene film, micron-grade aluminum oxide, nano-silicon powder, polyethylene wax, magnesium hydroxide and silane coupling agent, with polypropylene film accounting for 65%, micron-grade aluminum oxide accounting for 12%, nano-silicon powder accounting for 8%, polyethylene wax accounting for 5%, magnesium hydroxide accounting for 7%, and silane coupling agent accounting for 3%, providing high insulation performance and anti-aging ability, and adapting to complex use environments; As a technical solution for further implementing this scheme, the following steps are included: Step I: Installation and laying: According to the layout of the offshore wind power generation equipment, the cable is connected between the generator and the transformer through a preset laying pipeline or hanging device. During the laying process, the bending radius of the cable is ensured to be no less than 10 times its diameter, which can avoid cable damage and ensure the safe and reliable laying process; Step II: Conductor connection: At the cable joint, use a special aluminum conductor crimping device to crimp the aluminum alloy soft conductor 1. After crimping, use an antioxidant protective agent to seal the joint to ensure that the resistance at the connection is no more than 1.1 times the normal conductor resistance, which can ensure the conductive performance and long-term reliability of the connection point; Step III: Salt spray resistance test: After laying, the salt spray resistant and highly tear-resistant chlorinated polyethylene sheath 4 is subjected to a salt spray spray test. The concentration of the sodium chloride solution in the test environment is 5%, and the test time is 720 hours. It is ensured that there are no cracks or obvious corrosion on the surface of the sheath, which can verify the corrosion resistance of the sheath and improve the adaptability of the cable. Step IV: Regular maintenance: Check the conductor resistance, sheath integrity and insulation performance of the cable every six months to extend the overall life of the cable and ensure stable operation of the system; The cable has excellent flame retardant properties and can meet the single-wire combustion test. The product is light in weight and low in cost. It is 40-60% cheaper than cables with conventional tinned copper conductor structures. It is light in weight and easy to lay, which can greatly save construction costs.

[0018] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. The above is only a preferred implementation of the present invention. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the protection scope of the present invention.

Claims

1. An aluminum alloy core salt spray resistant cable for offshore wind power generation, comprising a light wrapped isolation layer (2), characterized in that: An aluminum alloy soft conductor (1) is installed inside the light wrapped isolation layer (2), an EPDM rubber insulation (3) is installed outside the light wrapped isolation layer (2), and a salt spray resistant, high tear resistance chlorinated polyethylene sheath (4) is installed outside the EPDM rubber insulation (3); The aluminum alloy soft conductor (1) is a conductor, which is made by adding carbon fiber components to the fifth aluminum alloy soft structure, and the specific formula includes aluminum, magnesium, silicon, iron, copper, zinc and short-cut carbon fiber, wherein the aluminum accounts for 97.5%, the magnesium accounts for 0.6%, the silicon accounts for 0.53%, the iron accounts for 0.3%, the copper accounts for 0.05%, the zinc accounts for 0.02% and the short-cut carbon fiber accounts for 1.0%; The light wrapped isolation layer (2) is an isolation layer, and the EPDM rubber insulation (3) is an insulation layer.

2. The aluminum alloy core salt spray resistant cable for offshore wind power generation according to claim 1 is characterized in that: The production process of the aluminum alloy soft conductor (1) is as follows: Step 1: Mixing and smelting: Mix the aluminum substrate and various alloy elements in proportion and smelt them at a temperature of 750°C - 800°C; Step 2: Uniform dispersion of carbon fiber: During the melting process, chopped carbon fiber is gradually added, and mechanical stirring and ultrasonic dispersion technology are used to ensure uniform distribution of carbon fiber; Step 3: Ingot forming: forming aluminum alloy base material through continuous casting technology; Step 4: Multi-pass drawing: The ingot is subjected to multi-pass drawing to control the single wire diameter within the target range; Step 5: Heat treatment: Use annealing process to eliminate processing stress and optimize electrical conductivity and mechanical strength.

3. The aluminum alloy core salt spray resistant cable for offshore wind power generation according to claim 2 is characterized in that: In the step 1, after the ingredients are smelted, they are kept warm for 15-20 minutes, during which time a refining agent is added to remove inclusions and gases.

4. The aluminum alloy core salt spray resistant cable for offshore wind power generation according to claim 2, characterized in that: In the step 2, the carbon fiber is selected from chopped fibers, the length of which is controlled to be 3-5 mm, and the surface is coated with an epoxy resin coating.

5. The aluminum alloy core salt spray resistant cable for offshore wind power generation according to claim 2, characterized in that: During the continuous casting process in step 3, the temperature of the aluminum liquid is controlled at 720°C - 740°C, an initial aluminum alloy ingot is formed by a water-cooled mold, the cooling rate is controlled at 5-10°C / second, and the ingot size diameter is in the range of 9 - 15 mm.

6. The aluminum alloy core salt spray resistant cable for offshore wind power generation according to claim 2 is characterized in that: The drawing step in step 4 is: S1: The ingot is initially rolled to form an intermediate billet with a diameter controlled at 4-5 mm; S2: Through 6-8 passes of gradual drawing, the diameter of the single wire is finally controlled within the range of 0.30-0.50 mm, and the surface is cleaned after each drawing; S3: During the drawing process, spray lubricant regularly.

7. The aluminum alloy core salt spray resistant cable for offshore wind power generation according to claim 2, characterized in that: In the annealing process in step 5, the single filament is heated to 250°C - 300°C in a continuous annealing furnace for 3-5 hours, and annealing is performed under argon protection.

8. The aluminum alloy core salt spray resistant cable for offshore wind power generation according to claim 1, characterized in that: The formula of the lightweight wrapped isolation layer includes polypropylene film, micron-grade aluminum oxide, nano-silicon powder, polyethylene wax, magnesium hydroxide and silane coupling agent, wherein the polypropylene film accounts for 65%, the micron-grade aluminum oxide accounts for 12%, the nano-silicon powder accounts for 8%, the polyethylene wax accounts for 5%, the magnesium hydroxide accounts for 7%, and the silane coupling agent accounts for 3%.

9. The method for using the aluminum alloy core salt spray resistant cable for offshore wind power generation according to any one of claims 1 to 8, characterized in that: The process includes the following steps: Step I: Installation and laying: According to the layout of the offshore wind power generation equipment, the cable is connected between the generator and the transformer through a preset laying pipeline or hanging device. During the laying process, the bending radius of the cable is ensured to be no less than 10 times its diameter; Step II: Conductor connection: At the cable joint, use a special aluminum conductor crimping device to crimp the aluminum alloy soft conductor (1). After crimping, use an antioxidant protective agent to seal the joint to ensure that the resistance at the joint is no more than 1.1 times the normal conductor resistance. Step III: Salt spray resistance test: After laying, the salt spray resistant, high tear resistance chlorinated polyethylene sheath (4) is subjected to a salt spray spray test. The test environment sodium chloride solution concentration is 5% and the test time is 720 hours to ensure that there are no cracks or obvious corrosion on the surface of the sheath; Step IV: Regular maintenance: Check the conductor resistance, sheath integrity and insulation performance of the cable every six months.

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