Photovoltaic cable and preparation method thereof

Abstract

The invention relates to the technical field of cables, and provides a photovoltaic cable and a preparation method thereof. The photovoltaic cable includes: a center conductor; the insulating layer is positioned on the periphery of the central conductor; the sheath layer is positioned on the periphery of the insulating layer; wherein the material of the insulating layer comprises cross-linked polyolefin and a first fluorocarbon polymer; the sheath layer is made of polyethylene, a second fluorocarbon polymer, ethylene propylene diene monomer, methyl vinyl silicone rubber, fluorinated silicone rubber, a modifier, a compatilizer and an accelerant. Therefore, the photovoltaic cable has excellent low-temperature performance and can bear tests such as impact and winding at low temperature.

Description

Technical Field

[0001] The present invention relates to the field of cable technology, and in particular to a photovoltaic cable and a preparation method thereof. Background Art

[0002] As one of the most important clean energy sources, the scale of photovoltaic power generation projects has been continuously expanding in recent years. The installed capacity of ground power stations and distributed household power stations has been increasing, the technology has been increasingly advanced, and the cost of power generation has been significantly reduced. While it is constantly developing, its reliability cannot be ignored. As one of the important auxiliary materials of the components, the junction box is responsible for transmitting the current generated by the components and playing a protective role when hot spots occur. Its safety is very important. The installation environment and working environment of photovoltaic components are complex and changeable. When the components work in extremely cold areas, they pose more severe challenges to the components of the junction box. At present, the junction box body and connector can meet the environmental requirements of -55℃, while conventional photovoltaic cables can only meet the performance requirements of -40℃. Working in a colder environment, the cable will undergo hardening and catalysis. When an impact occurs, there is a risk of rupture of the cable sheath insulation layer and short circuit breakdown, which will cause the entire power station system to short-circuit. Therefore, it is still necessary to provide a photovoltaic cable that can greatly improve the performance of the cable in a low temperature and cold environment to meet the working performance requirements. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, the present invention provides a photovoltaic cable and a preparation method thereof, wherein the photovoltaic cable has excellent low temperature performance and can withstand impact and winding tests at low temperatures.

[0004] To this end, the first aspect of the present invention provides a photovoltaic cable, comprising:

[0005] Center conductor;

[0006] an insulating layer located at the periphery of the central conductor;

[0007] A sheath layer located outside the insulating layer;

[0008] Wherein, the material of the insulating layer includes cross-linked polyolefin and a first fluorocarbon polymer;

[0009] The material of the sheath layer includes polyethylene, a second fluorocarbon polymer, ethylene propylene diene rubber, methyl vinyl silicone rubber, fluorosilicone rubber, a modifier, a compatibilizer and an accelerator.

[0010] Therefore, the photovoltaic cable has excellent insulation properties, and the addition of raw materials such as fluorocarbon polymer, EPDM rubber, methyl vinyl silicone rubber, and fluorosilicone rubber can synergistically improve the material's low-temperature resistance and flexibility at low temperatures, so that it can withstand impact and winding tests at low temperatures and meet work performance requirements.

[0011] According to an embodiment of the present invention, the cross-linked polyolefin includes cross-linked polyethylene.

[0012] According to an embodiment of the present invention, the first fluorocarbon polymer includes polytetrafluoroethylene and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.

[0013] According to an embodiment of the present invention, the insulating layer includes 50-90 parts by weight of a cross-linked polyolefin and 2.5-11 parts by weight of a first fluorocarbon polymer.

[0014] According to an embodiment of the present invention, the cross-linked polyolefin includes cross-linked polyethylene, and the fluorocarbon polymer includes polytetrafluoroethylene and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer;

[0015] The insulating layer comprises 50-90 parts by weight of cross-linked polyethylene, 2-8 parts by weight of polytetrafluoroethylene, and 0.5-3 parts by weight of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.

[0016] According to an embodiment of the present invention, the sheath layer includes 60-90 parts by weight of polyethylene, 4-15 parts by weight of a second fluorocarbon polymer, 3-10 parts by weight of ethylene propylene diene rubber, 3-10 parts by weight of methyl vinyl silicone rubber, 5-15 parts by weight of fluorosilicone rubber, 1-3 parts by weight of a modifier, 1-4 parts by weight of a compatibilizer, and 0.1-1 parts by weight of an accelerator.

[0017] According to an embodiment of the present invention, the second fluorocarbon polymer includes at least one of polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and tetrafluoroethylene-hexafluoropropylene copolymer.

[0018] According to an embodiment of the present invention, the fluorosilicone rubber includes γ-trifluoropropylmethylpolysiloxane.

[0019] According to an embodiment of the present invention, the modifier includes silanol.

[0020] According to an embodiment of the present invention, the modifier includes at least one of tri(trimethylsilyl)silanol, triethylsilanol, triisopropylsilanol, and methylsilanetriol.

[0021] According to an embodiment of the present invention, the compatibilizer includes (3-aminopropyl)trimethoxysilane.

[0022] According to an embodiment of the present invention, the accelerator includes dibenzothiazyl disulfide.

[0023] According to an embodiment of the present invention, the sheath layer includes 60-90 parts by weight of polyethylene, 3-9 parts by weight of polytetrafluoroethylene, 0.5-3 parts by weight of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 0.5-3 parts by weight of tetrafluoroethylene-hexafluoropropylene copolymer, 3-10 parts by weight of ethylene propylene diene rubber, 3-10 parts by weight of methyl vinyl silicone rubber, 5-15 parts by weight of γ-trifluoropropyl methyl polysiloxane, 1-3 parts by weight of methyl silanetriol, 1-4 parts by weight of (3-aminopropyl) trimethoxysilane, and 0.1-1 parts by weight of dibenzothiazole disulfide.

[0024] According to an embodiment of the present invention, the sheath layer further includes at least one of an antioxidant and a light stabilizer.

[0025] According to an embodiment of the present invention, the weight percentage of the antioxidant in the sheath layer is 0.1-0.6 parts.

[0026] According to an embodiment of the present invention, the weight portion of the light stabilizer in the sheath layer is 0.1-1 part.

[0027] According to an embodiment of the present invention, the material of the central conductor includes at least one of copper, silver, aluminum, and aluminum alloy.

[0028] The second aspect of the present invention provides a method for preparing the photovoltaic cable described in the first aspect, comprising sequentially coating an insulating layer and a sheath layer on the surface of a central conductor.

[0029] Thus, the photovoltaic cable is obtained which has excellent low temperature performance and can withstand impact and winding tests at low temperatures.

[0030] According to an embodiment of the present invention, after the insulating layer and the sheath layer are sequentially coated on the surface of the central conductor, a radiation cross-linking treatment is performed.

[0031] According to an embodiment of the present invention, the radiation dose of the radiation cross-linking treatment is 5-25 Mrad.

[0032] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0034] Figure 1 A cross-sectional view of an embodiment of a photovoltaic cable provided by the present invention is shown.

[0035] Reference numerals:

[0036] Central conductor 11 , insulating layer 12 , and sheath layer 13 . DETAILED DESCRIPTION

[0037] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0038] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present disclosure, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not mean that the present disclosure necessarily has the first element, component, region, layer or part.

[0039] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0040] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0041] In order to make the present invention more easily understood, certain technical and scientific terms are specifically defined below. Unless otherwise clearly defined elsewhere in this document, all other technical and scientific terms used herein have the meanings commonly understood by those skilled in the art to which the present invention belongs.

[0042] In this document, the terms “include” or “comprising” are open expressions, that is, including the contents specified in the present invention but not excluding other contents.

[0043] A first aspect of the present invention provides a photovoltaic cable, such as Figure 1 As shown, the photovoltaic cable includes: a central conductor 11 , an insulating layer 12 located at the periphery of the central conductor 11 , and a sheath layer 13 located at the periphery of the insulating layer 12 .

[0044] According to a specific embodiment of the present invention, the material of the central conductor 11 is not particularly limited, and those skilled in the art may select the material according to actual needs, such as copper, silver, aluminum, aluminum alloy, etc.

[0045] According to a specific embodiment of the present invention, the insulating layer 12 is located on the periphery of the central conductor 11, and includes a cross-linked polyolefin and a first fluorocarbon polymer. The base material of the insulating layer is cross-linked polyolefin, thereby ensuring that the photovoltaic cable insulating layer has excellent insulation performance. At the same time, the addition of fluorocarbon polymer can improve the low temperature resistance of the insulating layer, improve its flexibility at low temperatures, and further improve the insulation performance of the insulating layer.

[0046] According to a specific embodiment of the present invention, the types of the cross-linked polyolefin and the first fluorocarbon polymer are not particularly limited, and those skilled in the art can select them according to actual needs. The cross-linked polyolefin includes but is not limited to cross-linked polyethylene, etc., and the first fluorocarbon polymer includes but is not limited to polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), etc.

[0047] According to a specific embodiment of the present invention, the weight proportions of the cross-linked polyolefin and the first fluorocarbon polymer are not particularly limited, and those skilled in the art can select them according to actual needs. As some specific examples, the insulating layer includes 50-90 weight proportions of the cross-linked polyolefin, such as 50, 55, 60, 65, 70, 75, 80, 85, 90, etc.; the insulating layer includes 2.5-11 weight proportions of the first fluorocarbon polymer, such as 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, etc. Thus, the insulating layer has better insulation performance and low temperature resistance.

[0048] According to a specific embodiment of the present invention, the cross-linked polyolefin includes cross-linked polyethylene, and the fluorocarbon polymer includes polytetrafluoroethylene and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer. The insulating layer includes 50-90 parts by weight of cross-linked polyethylene, 2-8 parts by weight of polytetrafluoroethylene, and 0.5-3 parts by weight of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, for example, the weight of cross-linked polyethylene is 50, 55, 60, 65, 70, 75, 80, 85, 90, etc., the weight of polytetrafluoroethylene is 2, 3, 4, 5, 6, 7, 8, etc., and the weight of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer is 0.5, 1, 1.5, 2, 2.5, 3, etc. Thus, the insulating layer has better insulation performance and low temperature resistance.

[0049] According to a specific embodiment of the present invention, the sheath layer 13 is located on the periphery of the insulating layer 12, and mainly plays the role of protection and insulation. Its composition includes polyethylene, a second fluorocarbon polymer, EPDM rubber, methyl vinyl silicone rubber, fluorosilicone rubber, a modifier, a compatibilizer and a promoter.

[0050] The weight parts of polyethylene, the second fluorocarbon polymer, EPDM rubber, methyl vinyl silicone rubber, fluorosilicone rubber, modifier, compatibilizer and accelerator are not particularly limited, and those skilled in the art can select according to actual needs. As some specific examples, the sheath layer includes 60-90 weight parts of polyethylene, 4-15 weight parts of the second fluorocarbon polymer, 3-10 weight parts of EPDM rubber, 3-10 weight parts of methyl vinyl silicone rubber, 5-15 weight parts of fluorosilicone rubber, 1-3 weight parts of modifier, 1-4 weight parts of compatibilizer, and 0.1-1 weight parts of accelerator. For example, the weight parts of polyethylene are 60, 65, 70, 75, 80, 85, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 510, 520, 530, 540, 550 , 90, etc.; the weight fractions of the second fluorocarbon polymer are 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, etc.; for example, the weight fractions of EPDM rubber are 3, 4, 5, 6, 7, 8, 9, 10, etc.; the weight fractions of methyl vinyl silicone rubber are 3, 4, 5, 6, 7, 8, 9, 10, etc.; the weight fractions of fluorosilicone rubber are 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, etc.; the weight fractions of modifiers are 1, 1.5, 2, 2.5, 3, etc.; the weight fractions of compatibilizers are 1, 1.5, 2, 2.5, 3, 3.5, 4, etc.; the weight fractions of accelerators are 0.1, 0.5, 1, etc.

[0051] Specifically, polyethylene has a high insulation resistance, so that the sheath layer has good insulation performance. The type of polyethylene is not particularly limited, for example, low-density polyethylene (LDPE), high-density polyethylene (HDPE), etc. can be selected, preferably high-density polyethylene, and its weight average molecular weight is generally 40,000-300,000.

[0052] Specifically, the second fluorocarbon polymer can improve the low temperature resistance of the insulation layer, improve its flexibility at low temperatures, and further improve the insulation performance of the sheath layer. The type of the second fluorocarbon polymer is not particularly limited. As some specific examples, the second fluorocarbon polymer includes but is not limited to polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), preferably polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer and tetrafluoroethylene-hexafluoropropylene copolymer.

[0053] The polytetrafluoroethylene can improve the low temperature resistance of the sheath layer, improve its flexibility at low temperatures, and further improve the insulation performance of the sheath layer. The weight percentage of the polytetrafluoroethylene is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, the sheath layer includes 3-9 weight percentages of polytetrafluoroethylene, for example, the weight percentages of the polytetrafluoroethylene are 3, 4, 5, 6, 7, 8, 9, etc.

[0054] The tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer can improve the creep resistance and compression strength of the jacket layer at low temperatures. The weight percentage of the tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, the jacket layer includes 0.5-3 weight percentages of the tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, for example, the weight percentages of the tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer are 0.5, 1, 1.5, 2, 2.5, 3, etc.

[0055] The tetrafluoroethylene-hexafluoropropylene copolymer can improve the tensile strength of the jacket layer at low temperatures and the stability at ultra-low temperatures (-200°C). The weight fraction of the tetrafluoroethylene-hexafluoropropylene copolymer is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, the jacket layer includes 0.5-3 weight fractions of the tetrafluoroethylene-hexafluoropropylene copolymer, for example, the weight fractions of the tetrafluoroethylene-hexafluoropropylene copolymer are 0.5, 1, 1.5, 2, 2.5, 3, etc.

[0056] According to a specific embodiment of the present invention, EPDM rubber, methyl vinyl silicone rubber, and fluorosilicone rubber can effectively improve the low-temperature performance of the sheath layer.

[0057] Specifically, the type of fluorosilicone rubber is not particularly limited, and those skilled in the art may select it according to actual needs. As some specific examples, fluorosilicone rubber includes but is not limited to γ-trifluoropropylmethylpolysiloxane.

[0058] According to a specific embodiment of the present invention, the compatibilizer can improve the compatibility of each component material, and at the same time increase the hydrophobicity of the jacket layer, and maintain good insulation and mechanical properties in a low-temperature ice and snow environment. The type of compatibilizer is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, the compatibilizer includes but is not limited to (3-aminopropyl) trimethoxysilane.

[0059] According to a specific embodiment of the present invention, the modifier can modify the compatibilizer to further improve the compatibility of each component material. The type of modifier is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, the modifier includes but is not limited to silanol, specifically but not limited to tris(trimethylsilyl)silanol, triethylsilanol, triisopropylsilanol, and methylsilanetriol.

[0060] According to a specific embodiment of the present invention, the accelerator can improve the mechanical properties of EPDM rubber, methyl vinyl silicone rubber, and fluorosilicone rubber. The type of accelerator is also not particularly limited. Those skilled in the art can choose according to actual needs. As some specific examples, the accelerator includes but is not limited to dibenzothiazole disulfide.

[0061] According to a specific embodiment of the present invention, the sheath layer 13 further comprises at least one of an antioxidant and a light stabilizer, thereby improving the chemical stability and aging resistance of the sheath material.

[0062] Specifically, the types of antioxidants include, but are not limited to, antioxidant 168, antioxidant 1035, antioxidant 1010, and antioxidant 1076. The weight fraction of the antioxidant in the sheath layer is not particularly limited, and those skilled in the art can select it according to actual needs. As some specific examples, the weight fraction of the antioxidant in the sheath layer is 0.1-0.6 parts, such as 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, etc.

[0063] Specifically, the light stabilizer includes, but is not limited to, antioxidant 622, antioxidant 770, antioxidant 292, and antioxidant 1130. The weight fraction of the light stabilizer in the sheath layer is not particularly limited, and those skilled in the art may select it according to actual needs. As some specific examples, the weight fraction of the light stabilizer in the sheath layer is 0.1-1 part, such as 0.1 part, 0.2 part, 0.3 part, 0.4 part, 0.5 part, 0.6 part, 0.7 part, 0.8 part, 0.9 part, 1 part, etc.

[0064] According to an embodiment of the present invention, a second aspect of the present invention provides a method for preparing the photovoltaic cable described in the first aspect. The preparation method comprises sequentially coating an insulating layer and a sheath layer on the surface of a central conductor.

[0065] According to a specific embodiment of the present invention, the insulating layer and the sheath layer can be prepared separately, first forming the insulating layer on the periphery of the central conductor, and then forming the sheath layer. For example:

[0066] (1) Mixing the cross-linked polyolefin and the first fluorocarbon polymer according to the above formula, stirring until the mixture is uniform, the stirring speed may be 400-700 rpm, extruding, granulating, and cooling at 170-210° C. to obtain an insulating material;

[0067] (2) adding polyethylene, a second fluorocarbon polymer, ethylene propylene diene rubber, methyl vinyl silicone rubber, fluorosilicone rubber, a modifier, a compatibilizer and an accelerator into a mixer according to the above formula, setting the speed to 600-800 rpm, stirring until the mixture is uniform, extruding, granulating and cooling at 190-250° C. to obtain a sheath material;

[0068] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and forming to obtain an insulating layer cable;

[0069] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0070] (5) Using an electron accelerator to irradiate and cross-link the obtained cable, the irradiation dose is 5-25 Mrad, thereby obtaining the photovoltaic cable of the present invention.

[0071] The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0072] Example 1

[0073] A method for preparing a photovoltaic cable comprises the following steps:

[0074] (1) 50 parts of cross-linked polyethylene, 2 parts of polytetrafluoroethylene, and 0.5 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer were stirred at 700 rpm until uniformly mixed, and then extruded, granulated, and cooled at 210° C. to obtain an insulating material;

[0075] (2) 60 parts of high-density polyethylene, 3 parts of polytetrafluoroethylene, 0.5 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 0.5 parts of tetrafluoroethylene-hexafluoropropylene copolymer, 3 parts of ethylene propylene diene rubber, 3 parts of methyl vinyl silicone rubber, 5 parts of γ-trifluoropropyl methyl polysiloxane, 1 part of methyl silanetriol, 1 part of (3-aminopropyl) trimethoxysilane, 0.1 parts of dibenzothiazole disulfide, 0.1 parts of antioxidant 168, and 0.1 parts of antioxidant 622 are added into a mixer, the speed is set to 800 rpm and stirred until the mixture is uniformly mixed, and then extruded, granulated, and cooled at 250° C. to obtain a sheath material;

[0076] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and molding to obtain an insulating layer cable;

[0077] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0078] (5) Using an electron accelerator, the obtained cable is irradiated and cross-linked, with an irradiation dose of 25 Mrad.

[0079] Example 2

[0080] A method for preparing a photovoltaic cable comprises the following steps:

[0081] (1) 90 parts of cross-linked polyethylene, 8 parts of polytetrafluoroethylene, and 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer were stirred at 700 rpm until uniformly mixed, and then extruded, granulated, and cooled at 210° C. to obtain an insulating material;

[0082] (2) 90 parts of high-density polyethylene, 9 parts of polytetrafluoroethylene, 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 3 parts of tetrafluoroethylene-hexafluoropropylene copolymer, 10 parts of ethylene propylene diene rubber, 10 parts of methyl vinyl silicone rubber, 15 parts of γ-trifluoropropyl methyl polysiloxane, 3 parts of methyl silanetriol, 4 parts of (3-aminopropyl) trimethoxysilane, 1 part of dibenzothiazole disulfide, 0.6 parts of antioxidant 1035, and 1 part of antioxidant 770 are added into a mixer, the speed is set to 800 rpm and stirred until the mixture is uniformly mixed, and then extruded, granulated, and cooled at 250° C. to obtain a sheath material;

[0083] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and molding to obtain an insulating layer cable;

[0084] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0085] (5) Using an electron accelerator, the obtained cable is irradiated and cross-linked, with an irradiation dose of 25 Mrad.

[0086] Comparative Example 1

[0087] A method for preparing a photovoltaic cable comprises the following steps:

[0088] (1) 90 parts of cross-linked polyethylene and 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer were stirred at 700 rpm until they were uniformly mixed, and then extruded, granulated, and cooled at 210° C. to obtain an insulating material;

[0089] (2) 90 parts of high-density polyethylene, 9 parts of polytetrafluoroethylene, 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 3 parts of tetrafluoroethylene-hexafluoropropylene copolymer, 10 parts of ethylene propylene diene rubber, 10 parts of methyl vinyl silicone rubber, 15 parts of γ-trifluoropropyl methyl polysiloxane, 3 parts of methyl silanetriol, 4 parts of (3-aminopropyl) trimethoxysilane, 1 part of dibenzothiazole disulfide, 0.6 parts of antioxidant 1010, and 1 part of antioxidant 292 are added into a mixer, the speed is set to 800 rpm and stirred until the mixture is uniformly mixed, and then extruded, granulated, and cooled at 250° C. to obtain a sheath material;

[0090] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and molding to obtain an insulating layer cable;

[0091] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0092] (5) Using an electron accelerator, the obtained cable is irradiated and cross-linked, with an irradiation dose of 25 Mrad.

[0093] Comparative Example 2

[0094] A method for preparing a photovoltaic cable comprises the following steps:

[0095] (1) 90 parts of cross-linked polyethylene and 8 parts of polytetrafluoroethylene were stirred at 700 rpm until they were uniformly mixed, and then extruded, granulated, and cooled at 210° C. to obtain an insulating material;

[0096] (2) 90 parts of high-density polyethylene, 9 parts of polytetrafluoroethylene, 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 3 parts of tetrafluoroethylene-hexafluoropropylene copolymer, 10 parts of ethylene propylene diene monomer rubber, 10 parts of methyl vinyl silicone rubber, 15 parts of γ-trifluoropropyl methyl polysiloxane, 3 parts of methyl silanetriol, 4 parts of (3-aminopropyl) trimethoxysilane, 1 part of dibenzothiazole disulfide, 0.6 parts of antioxidant 1076, and 1 part of antioxidant 1130 are added into a mixer, the speed is set to 800 rpm and stirred until the mixture is uniformly mixed, and then extruded, granulated, and cooled at 250° C. to obtain a sheath material;

[0097] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and molding to obtain an insulating layer cable;

[0098] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0099] (5) Using an electron accelerator, the obtained cable is irradiated and cross-linked, with an irradiation dose of 25 Mrad.

[0100] Comparative Example 3

[0101] A method for preparing a photovoltaic cable comprises the following steps:

[0102] (1) 90 parts of cross-linked polyethylene, 8 parts of polytetrafluoroethylene, and 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer were stirred at 700 rpm until uniformly mixed, and then extruded, granulated, and cooled at 210° C. to obtain an insulating material;

[0103] (2) 90 parts of high-density polyethylene, 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 3 parts of tetrafluoroethylene-hexafluoropropylene copolymer, 10 parts of ethylene propylene diene monomer rubber, 10 parts of methyl vinyl silicone rubber, 15 parts of γ-trifluoropropyl methyl polysiloxane, 3 parts of methyl silanetriol, 4 parts of (3-aminopropyl) trimethoxysilane, 1 part of dibenzothiazole disulfide, 0.6 parts of antioxidant 1035, and 1 part of antioxidant 770 were added into a mixer, the speed was set to 800 rpm and stirred until the mixture was uniformly mixed, and then extruded, granulated, and cooled at 250° C. to obtain a sheath material;

[0104] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and molding to obtain an insulating layer cable;

[0105] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0106] (5) Using an electron accelerator, the obtained cable is irradiated and cross-linked, with an irradiation dose of 25 Mrad.

[0107] Comparative Example 4

[0108] A method for preparing a photovoltaic cable comprises the following steps:

[0109] (1) 90 parts of cross-linked polyethylene, 8 parts of polytetrafluoroethylene, and 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer were stirred at 700 rpm until uniformly mixed, and then extruded, granulated, and cooled at 210° C. to obtain an insulating material;

[0110] (2) 90 parts of high-density polyethylene, 9 parts of polytetrafluoroethylene, 10 parts of ethylene propylene diene rubber, 10 parts of methyl vinyl silicone rubber, 15 parts of γ-trifluoropropyl methyl polysiloxane, 3 parts of methyl silanetriol, 4 parts of (3-aminopropyl) trimethoxysilane, 1 part of dibenzothiazole disulfide, 0.6 parts of antioxidant 1035, and 1 part of antioxidant 770 were added into a mixer, the speed was set to 800 rpm and stirred until the mixture was uniformly mixed, and then extruded, granulated, and cooled at 250° C. to obtain a sheath material;

[0111] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and molding to obtain an insulating layer cable;

[0112] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0113] (5) Using an electron accelerator, the obtained cable is irradiated and cross-linked, with an irradiation dose of 25 Mrad.

[0114] Comparative Example 5

[0115] A method for preparing a photovoltaic cable comprises the following steps:

[0116] (1) 90 parts of cross-linked polyethylene, 8 parts of polytetrafluoroethylene, and 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer were stirred at 700 rpm until uniformly mixed, and then extruded, granulated, and cooled at 210° C. to obtain an insulating material;

[0117] (2) adding 90 parts of high-density polyethylene, 9 parts of polytetrafluoroethylene, 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 3 parts of tetrafluoroethylene-hexafluoropropylene copolymer, 3 parts of methylsilanetriol, 4 parts of (3-aminopropyl)trimethoxysilane, 1 part of dibenzothiazole disulfide, 0.6 parts of antioxidant 1035, and 1 part of antioxidant 770 into a mixer, setting the speed to 800 rpm and stirring until the mixture is uniformly mixed, and then extruding, granulating, and cooling at 250° C. to obtain a sheath material;

[0118] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and molding to obtain an insulating layer cable;

[0119] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0120] (5) Using an electron accelerator, the obtained cable is irradiated and cross-linked, with an irradiation dose of 25 Mrad.

[0121] Comparative Example 6

[0122] A method for preparing a photovoltaic cable comprises the following steps:

[0123] (1) 90 parts of cross-linked polyethylene, 8 parts of polytetrafluoroethylene, and 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer were stirred at 700 rpm until uniformly mixed, and then extruded, granulated, and cooled at 210° C. to obtain an insulating material;

[0124] (2) 90 parts of high-density polyethylene, 9 parts of polytetrafluoroethylene, 3 parts of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 3 parts of tetrafluoroethylene-hexafluoropropylene copolymer, 10 parts of ethylene propylene diene monomer rubber, 10 parts of methyl vinyl silicone rubber, 15 parts of γ-trifluoropropyl methyl polysiloxane, 0.6 parts of antioxidant 1035, and 1 part of antioxidant 770 were added into a mixer, the speed was set to 800 rpm and stirred until the mixture was uniformly mixed, and then extruded, granulated, and cooled at 250° C. to obtain a sheath material;

[0125] (3) adding the insulating material into the wire extruder, extruding the conductor through the insulating material, and cooling and molding to obtain an insulating layer cable;

[0126] (4) adding the sheath material to a cable extruder, extruding the insulating layer cable through the extruder, and cooling and molding to obtain a cable;

[0127] (5) Using an electron accelerator, the obtained cable is irradiated and cross-linked, with an irradiation dose of 25 Mrad.

[0128] Test example:

[0129] The photovoltaic cables prepared in the embodiments and comparative examples were subjected to the following tests, specifically:

[0130] 1. Low temperature impact test:

[0131] Refer to IEC 62930, place the sample in a -55℃ environment for 16 hours, impact the cable with 8J energy three times, and check whether the cable appearance is abnormal.

[0132] 2. Winding test:

[0133] Refer to IEC 62930, place the sample in a -55℃ environment for 16 hours, the diameter of the metal mandrel is 4-5 times the outer diameter of the wire, wind it 4 times, and check whether there is any abnormality in the appearance of the cable.

[0134] 3. Low temperature elongation test:

[0135] Referring to IEC 62930, after placing the sample in a -55℃ environment for 16 hours, install the cable sample on the fixture of the tensile testing machine, ensure that both ends of the sample are firmly clamped, and the sample can freely stretch during the stretching process without being disturbed by other objects; set the data recording parameters during the test, such as elongation, etc. Start the tensile testing machine and begin to apply tensile force to the cable sample. During the stretching process, the tensile testing machine automatically records the elongation of the sample and the tensile force it bears. Observe the changes in the sample, such as whether cracks, deformation, etc., and record the relevant data. When the sample breaks during the stretching process, the tensile testing machine automatically stops and records the elongation. Use the formula "elongation = sample length at tensile break / initial length of the sample" to calculate the low-temperature elongation of the cable.

[0136] 4. Tensile strength test:

[0137] Refer to IEC 62930, install the cable sample on the fixture of the tensile testing machine, ensure that both ends of the sample are firmly clamped, and the sample can stretch freely during the stretching process without being disturbed by other objects; set the data recording parameters during the test, such as maximum tension, elongation, etc. Start the tensile testing machine and begin to apply tensile force to the cable sample. During the stretching process, the tensile testing machine automatically records the elongation of the sample and the tensile force it withstands. Observe the changes in the sample, such as whether cracks, deformation, etc., and record relevant data. When the sample breaks during the stretching process, the tensile testing machine automatically stops and records the maximum tensile force value. Use the formula "tensile strength = maximum tension / cross-sectional area of ​​the sample" to calculate the tensile strength of the cable. The result is usually expressed in N / m 2 Or expressed in units such as MPa.

[0138] The results are shown in Table 1.

[0139] Table 1

[0140] Low temperature impact performance Low temperature winding performance Low temperature elongation (%) Tensile strength(MPa) Example 1 No abnormality in appearance No abnormality in appearance 126 14 Example 2 No abnormality in appearance No abnormality in appearance 128 14.2 Comparative Example 1 Slight cracks Slight cracks 116 13 Comparative Example 2 Slight cracks Slight cracks 117 11.2 Comparative Example 3 Slight cracks Slight cracks 112 12.5 Comparative Example 4 Slight cracks Slight cracks 114 11 Comparative Example 5 Severe cracks Severe cracks 101 11.8 Comparative Example 6 Severe cracks Severe cracks 98 9

[0141] The results show that compared with comparative examples 1-6, the photovoltaic cables prepared in examples 1-2 have better low temperature resistance and better flexibility at low temperatures, and can better meet the working performance requirements.

[0142] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0143] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A photovoltaic cable, characterized in that: The photovoltaic cable comprises: Center conductor; an insulating layer located at the periphery of the central conductor; A sheath layer located outside the insulating layer; Wherein, the material of the insulating layer includes cross-linked polyolefin and a first fluorocarbon polymer; The material of the sheath layer includes polyethylene, a second fluorocarbon polymer, ethylene propylene diene monomer rubber, methyl vinyl silicone rubber, fluorosilicone rubber, a modifier, a compatibilizer and an accelerator.

2. The photovoltaic cable according to claim 1, characterized in that: The cross-linked polyolefin comprises cross-linked polyethylene; Optionally, the first fluorocarbon polymer comprises at least one of polytetrafluoroethylene and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.

3. The photovoltaic cable according to claim 1, characterized in that: The insulating layer comprises 50-90 parts by weight of a cross-linked polyolefin and 2.5-11 parts by weight of a first fluorocarbon polymer; Optionally, the cross-linked polyolefin includes cross-linked polyethylene, and the fluorocarbon polymer includes polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer; The insulating layer comprises 50-90 parts by weight of cross-linked polyethylene, 2-8 parts by weight of polytetrafluoroethylene, and 0.5-3 parts by weight of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.

4. The photovoltaic cable according to claim 1, characterized in that: The sheath layer comprises 60-90 parts by weight of polyethylene, 4-15 parts by weight of a second fluorocarbon polymer, 3-10 parts by weight of ethylene propylene diene rubber, 3-10 parts by weight of methyl vinyl silicone rubber, 5-15 parts by weight of fluorosilicone rubber, 1-3 parts by weight of a modifier, 1-4 parts by weight of a compatibilizer, and 0.1-1 parts by weight of an accelerator; Optionally, the second fluorocarbon polymer includes at least one of polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and tetrafluoroethylene-hexafluoropropylene copolymer; Optionally, the fluorosilicone rubber comprises γ-trifluoropropylmethylpolysiloxane; Optionally, the modifier comprises a silanol; Optionally, the modifier includes at least one of tris(trimethylsilyl)silanol, triethylsilanol, triisopropylsilanol, and methylsilanetriol; Optionally, the compatibilizer includes (3-aminopropyl)trimethoxysilane; Optionally, the accelerator comprises dibenzothiazyl disulfide; Optionally, the sheath layer comprises 60-90 parts by weight of polyethylene, 3-9 parts by weight of polytetrafluoroethylene, 0.5-3 parts by weight of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, 0.5-3 parts by weight of tetrafluoroethylene-hexafluoropropylene copolymer, 3-10 parts by weight of ethylene propylene diene rubber, 3-10 parts by weight of methyl vinyl silicone rubber, 5-15 parts by weight of γ-trifluoropropyl methyl polysiloxane, 1-3 parts by weight of methyl silanetriol, 1-4 parts by weight of (3-aminopropyl) trimethoxysilane, and 0.1-1 parts by weight of dibenzothiazole disulfide.

5. The photovoltaic cable according to claim 1, characterized in that: The sheath layer further comprises at least one of an antioxidant and a light stabilizer.

6. The photovoltaic cable according to claim 5, characterized in that: The weight percentage of the antioxidant in the sheath layer is 0.1-0.6 parts; Optionally, the weight portion of the light stabilizer in the sheath layer is 0.1-1 part.

7. The photovoltaic cable according to any one of claims 1 to 6, characterized in that: The material of the central conductor includes at least one of copper, silver, aluminum and aluminum alloy.

8. A method for preparing the photovoltaic cable according to any one of claims 1 to 7, characterized in that: The method comprises sequentially coating an insulating layer and a sheath layer on the surface of a central conductor.

9. The method according to claim 8, characterized in that After the surface of the central conductor is coated with an insulation layer and a sheath layer in sequence, a radiation cross-linking treatment is performed.

10. The method according to claim 9, characterized in that The radiation dose of the radiation cross-linking treatment is 5-25 Mrad.

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