High-weather-resistance photovoltaic cable

Abstract

The invention relates to the technical field of photovoltaic cables, and provides a high-weather-resistance photovoltaic cable which is composed of three layers including a conductor, an insulating layer and a sheath layer from inside to outside in sequence. The sheath layer is prepared from the following raw materials in parts by weight: 40 to 60 parts of ethylene-vinyl acetate copolymer, 8 to 15 parts of hydroxyl-terminated polybutadiene rubber, 5 to 10 parts of plasticizer, 0.5 to 1.5 parts of antioxidant, 0.5 to 1 part of light stabilizer, 10 to 15 parts of filler, 8 to 12 parts of flame retardant and 0.5 to 1.5 parts of cross-linking agent; the mass ratio of the ethylene-vinyl acetate copolymer to the hydroxyl-terminated polybutadiene rubber is (1: 6)-(6: 1). According to the technical scheme, the problem of low weather resistance of the photovoltaic cable in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic cables, and in particular to a highly weather-resistant photovoltaic cable. Background Art

[0002] Photovoltaic cable is a special cable used to connect photovoltaic modules and inverters in solar photovoltaic power generation systems, and to transmit electricity between inverters and power grids. Photovoltaic cables usually need to operate for a long time in harsh outdoor environmental conditions, facing the test of high temperature, low temperature, ultraviolet radiation, humidity, wind and sand, etc. If photovoltaic cables do not have high weather resistance, they will cause serious harm. On the one hand, the insulation performance of the cable will drop rapidly, which may cause safety accidents such as leakage and short circuit, affecting the normal operation of the photovoltaic system. On the other hand, the service life of the cable will be greatly shortened. Frequent replacement of cables not only increases costs, but also affects the power generation efficiency of the photovoltaic system. Therefore, the development of a highly weather-resistant photovoltaic cable is of great significance to improving the stability and reliability of photovoltaic power generation systems, extending the service life of cables, and reducing system maintenance costs. Summary of the invention

[0003] The present invention provides a highly weather-resistant photovoltaic cable, which solves the problem of low weather resistance of photovoltaic cables in related technologies.

[0004] The technical scheme of the present invention is as follows: The present invention provides a high weather resistance photovoltaic cable, which consists of three layers, from the inside to the outside, which are a conductor, an insulating layer and a sheath layer, and the sheath layer comprises the following raw materials in parts by weight: 40-60 parts of ethylene-vinyl acetate copolymer, 8-15 parts of terminal hydroxyl polybutadiene rubber, 5-10 parts of plasticizer, 0.5-1.5 parts of antioxidant, 0.5-1 parts of light stabilizer, 10-15 parts of filler, 8-12 parts of flame retardant, and 0.5-1.5 parts of cross-linking agent; The mass ratio of the ethylene-vinyl acetate copolymer to the hydroxyl-terminated polybutadiene rubber is 1:6 to 6:1.

[0005] As a further technical solution, the conductor is made of copper.

[0006] As a further technical solution, the insulating layer is a cross-linked polyethylene insulating layer.

[0007] As a further technical solution, the mass ratio of the ethylene-vinyl acetate copolymer to the hydroxyl-terminated polybutadiene rubber is 5-6:1.

[0008] As a further technical solution, the Vicat softening temperature of the ethylene-vinyl acetate copolymer is 76-88.3°C.

[0009] The present invention limits the Vicat softening temperature of ethylene-vinyl acetate copolymer, and optimizes the optimal Vicat softening temperature to be 80° C., thereby ensuring that the photovoltaic cable can maintain good structural stability under high and low temperature environments and improving the weather resistance of the photovoltaic cable.

[0010] As a further technical solution, the plasticizer includes one or more of dioctyl phthalate, dioctyl terephthalate, and dioctyl sebacate.

[0011] As a further technical solution, the antioxidant includes one or more of antioxidant 1010 , antioxidant 1076 , and antioxidant 626 .

[0012] As a further technical solution, the light stabilizer includes one or more of Tinuvin 770, Chimassorb 944, and Hostavin N30.

[0013] As a further technical solution, the filler is modified talcum powder, the modifier of the modified talcum powder is polybutyl acrylate, and the mass ratio of the polybutyl acrylate to the talcum powder is 3-4:20.

[0014] In the present invention, polybutyl acrylate is used as a modifier of talcum powder to enhance the interaction between talcum powder and ethylene-vinyl acetate copolymer and hydroxyl-terminated polybutadiene rubber, thereby improving the weather resistance of the photovoltaic cable.

[0015] As a further technical solution, the preparation method of the modified talc powder comprises the following steps: dissolving the modifier in a solvent, adding the pretreated talc powder, heating and high-speed stirring to obtain the modified talc powder, and performing reduced pressure distillation after the reaction is completed.

[0016] As a further technical solution, at least one of the following technical features is also included: The flame retardant includes one or more of aluminum hydroxide, magnesium hydroxide, and antimony trioxide; The cross-linking agent includes one or more of dicumyl peroxide, benzoyl peroxide, and di-tert-butyl peroxide.

[0017] The present invention also provides a method for preparing a highly weather-resistant photovoltaic cable, comprising the following steps: S1, mixing the raw materials of the sheath layer uniformly, and extruding to obtain a sheath layer; S2. Wrap the insulation layer and the sheath layer around the conductor in sequence to obtain a cable.

[0018] As a further technical solution, the extrusion temperature is 150-180°C.

[0019] The working principle and beneficial effects of the present invention are: In the present invention, ethylene-vinyl acetate copolymer and terminal hydroxyl polybutadiene rubber are used as raw materials at the same time. By limiting the mass ratio of the two, the synergistic effect of the two is brought into play, and the force between the two is adjusted to maintain the physical structure stability inside the material, thereby improving the weather resistance of the photovoltaic cable. DETAILED DESCRIPTION

[0020] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] In the following examples and comparative examples: Hydroxyl-terminated polybutadiene rubber: model number is 69102-90-5, manufacturer is Tianyuan Aerospace Materials (Yingkou) Technology Co., Ltd.; Polybutyl acrylate: density is 1.087 g / mL, the manufacturer is Hubei Wonder Chemical Co., Ltd.; The insulation material is cross-linked polyethylene; The conductor material is copper.

[0022] Example 1 S1. Weigh 40 parts of ethylene-vinyl acetate copolymer, 10 parts of hydroxyl-terminated polybutadiene rubber, 5 parts of dioctyl phthalate, 0.5 parts of antioxidant 1010, 0.5 parts of light stabilizer Tinuvin 770, 10 parts of talc, 8 parts of aluminum hydroxide, and 0.5 parts of dicumyl peroxide, mix them evenly, and extrude them at 150° C. to obtain a sheath layer; wherein the Vicat softening temperature of the ethylene-vinyl acetate copolymer is 68° C. (model FL 00018, VA content 17.5wt%, manufacturer ExxonMobil Chemical Co., Ltd.); S2. Wrap the insulation layer and the sheath layer around the conductor in sequence to obtain a highly weather-resistant photovoltaic cable.

[0023] Example 2 S1. Weigh 50 parts of ethylene-vinyl acetate copolymer, 12.5 parts of hydroxyl-terminated polybutadiene rubber, 8 parts of dioctyl terephthalate, 1 part of antioxidant 1076, 0.8 parts of light stabilizer Chimassorb 944, 12 parts of talc, 10 parts of magnesium hydroxide, and 1 part of benzoyl peroxide, mix them evenly, and extrude them at 165° C. to obtain a sheath layer; wherein the Vicat softening temperature of the ethylene-vinyl acetate copolymer is 68° C. (model FL 00018, VA content 17.5wt%, manufacturer ExxonMobil Chemical Co., Ltd.); S2. Wrap the insulation layer and the sheath layer around the conductor in sequence to obtain a highly weather-resistant photovoltaic cable.

[0024] Example 3 S1. Weigh 60 parts of ethylene-vinyl acetate copolymer, 15 parts of hydroxyl-terminated polybutadiene rubber, 10 parts of dioctyl sebacate, 1.5 parts of antioxidant 626, 1 part of light stabilizer Hostavin N30, 15 parts of talc, 12 parts of antimony trioxide, and 1.5 parts of di-tert-butyl peroxide, mix them evenly, and extrude them at 180° C. to obtain a sheath layer; wherein the Vicat softening temperature of the ethylene-vinyl acetate copolymer is 68° C. (model FL 00018, VA content 17.5wt%, manufacturer ExxonMobil Chemical Co., Ltd.); S2. Wrap the insulation layer and the sheath layer around the conductor in sequence to obtain a highly weather-resistant photovoltaic cable.

[0025] Example 4 Compared with Example 3, the difference of Example 4 is that the added amount of the hydroxyl-terminated polybutadiene rubber is 12 parts.

[0026] Example 5 Compared with Example 3, the difference in Example 5 is that the added amount of the hydroxyl-terminated polybutadiene rubber is 10 parts.

[0027] Example 6 Compared with Example 3, the difference of Example 6 is that the added amount of the hydroxyl-terminated polybutadiene rubber is 8 parts.

[0028] Example 7 Compared with Example 5, Example 7 is different in that the Vicat softening temperature of ethylene-vinyl acetate copolymer is 76° C. (model FL 00014, VA content 14 wt %, manufacturer ExxonMobil Chemical Co., Ltd.).

[0029] Example 8 Compared with Example 5, Example 8 is different in that the Vicat softening temperature of ethylene-vinyl acetate copolymer is 80° C. (model: Low EVA-00111, VA content: 7.5 wt %, manufacturer: ExxonMobil Chemical Co., Ltd.).

[0030] Example 9 Compared with Example 5, Example 9 is different in that the Vicat softening temperature of ethylene-vinyl acetate copolymer is 88.3° C. (model LD 302.20, VA content 3.5 wt %, manufacturer ExxonMobil Chemical Co., Ltd.).

[0031] Example 10 Compared with Example 5, Example 10 is different in that the Vicat softening temperature of ethylene-vinyl acetate copolymer is 90° C. (model LD 144.50, VA content 2 wt %, manufacturer ExxonMobil Chemical Co., Ltd.).

[0032] Embodiment 11 Preparation of modified talc: dissolve 2 parts of polybutyl acrylate in 100 parts of toluene, pass the talc through a 325 mesh sieve, and dry at 120°C for 3 hours to obtain pretreated talc. Disperse the pretreated talc in the toluene solution of polybutyl acrylate, heat to 80°C, stir at 2000r / min for 2 hours, and remove the solvent by reduced pressure distillation at 70°C and 8kPa to obtain modified talc.

[0033] Compared with Example 8, the difference of Example 11 is that the talc powder is replaced with an equal amount of modified talc powder obtained by the above preparation method.

[0034] Example 12 Compared with Example 11, the difference in Example 12 is that the amount of polybutyl acrylate added is 3 parts.

[0035] Embodiment 13 Compared with Example 11, the difference in Example 13 is that the amount of polybutyl acrylate added is 4 parts.

[0036] Embodiment 14 Compared with Example 11, the difference in Example 14 is that the added amount of polybutyl acrylate is 5 parts.

[0037] Comparative Example 1 Compared with Example 3, the difference in Comparative Example 1 is that the ethylene-vinyl acetate copolymer is replaced by an equal amount of hydroxyl-terminated polybutadiene rubber.

[0038] Comparative Example 2 Compared with Example 3, the difference in Comparative Example 2 is that the hydroxyl-terminated polybutadiene rubber is replaced by an equal amount of ethylene-vinyl acetate copolymer.

[0039] The high weather resistance photovoltaic cable sheath layers prepared in Examples 1 to 14 and Comparative Examples 1 to 2 were tested according to the following method: 1. Weather resistance: Test the weather resistance of the sample according to the test method specified in GB / T 3511-2018 Weather resistance of vulcanized rubber or thermoplastic rubber.

[0040] 2. Low-temperature elongation at break: After placing the cable in a -40℃ environment for 16 hours, test the elongation at break of the sample in accordance with the test method for elongation at break specified in GB / T 2951.11-2008 "General test methods for insulation and sheath materials of electric and optical cables Part 11: General test methods for thickness and dimensional measurement - Mechanical properties test".

[0041] 3. Change rate of elongation in moisture and heat resistance: After placing the cable sheath layer in an environment with a temperature of 90°C and a humidity of 85% for 1000 hours, the moisture and heat resistance elongation of the sample is tested according to the test method specified in GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber". Change rate of elongation in moisture and heat resistance = elongation in moisture and heat resistance - original elongation.

[0042] The test results are shown in the following table: Table 1 Performance test results of high weather resistance photovoltaic cables prepared in Examples 1 to 14 and Comparative Examples 1 to 2

[0043] Compared with Example 3, Comparative Example 1 only adds hydroxyl-terminated polybutadiene rubber, and Comparative Example 2 only adds ethylene-vinyl acetate copolymer. As a result, the weather resistance and low-temperature elongation at break of Example 3 are better than those of Comparative Examples 1 and 2, and the change rate of wet heat elongation resistance is less than that of Comparative Examples 1 and 2, indicating that ethylene-vinyl acetate copolymer and hydroxyl-terminated polybutadiene rubber play a synergistic role and can improve the weather resistance of photovoltaic cables. Compared with Example 3, Examples 4 to 6 add ethylene-vinyl acetate copolymer and hydroxyl-terminated polybutadiene rubber in different mass ratios. As a result, the low-temperature elongation at break of Examples 4 and 5 is better than that of Examples 3 and 6, and the change rate of wet heat elongation resistance is less than that of Examples 3 and 6, indicating that when the mass ratio of ethylene-vinyl acetate copolymer and hydroxyl-terminated polybutadiene rubber is 5 to 6:1, the weather resistance of the obtained photovoltaic cable is better.

[0044] Compared with Example 5, Examples 7 to 10 add ethylene-vinyl acetate copolymers with different Vicat softening temperatures. As a result, the low-temperature elongation at break of Examples 7 to 9 is better than that of Examples 5 and 10, and the change rate of wet and hot elongation resistance is less than that of Examples 5 and 10, indicating that when the Vicat softening temperature of the ethylene-vinyl acetate copolymer is 76 to 88.3°C, and preferably when the Vicat softening temperature is 80°C, the weather resistance of the obtained photovoltaic cable is better.

[0045] Compared with Example 8, Examples 11 to 14 added modified talcum powder, and the low-temperature elongation at break of Examples 11 to 14 was better than that of Example 8, and the change rate of wet heat elongation was less than that of Example 8, indicating that the addition of modified talcum powder can improve the weather resistance of photovoltaic cables. In Examples 11 to 14, modifiers of different masses were added, and the low-temperature elongation at break of Examples 12 and 13 was better than that of Examples 11 and 14, and the change rate of wet heat elongation was less than that of Examples 11 and 14, indicating that when the mass ratio of polybutyl acrylate to talcum powder is 3 to 4:20, the weather resistance of the obtained photovoltaic cable is better.

[0046] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A highly weather-resistant photovoltaic cable, It is characterized in that The invention is composed of three layers, which are, from the inside to the outside, a conductor, an insulating layer and a sheath layer. The sheath layer comprises the following raw materials in parts by weight: 40 to 60 parts of ethylene-vinyl acetate copolymer, 8 to 15 parts of terminal hydroxyl polybutadiene rubber, 5 to 10 parts of plasticizer, 0.5 to 1.5 parts of antioxidant, 0.5 to 1 part of light stabilizer, 10 to 15 parts of talc, 8 to 12 parts of flame retardant and 0.5 to 1.5 parts of cross-linking agent; the mass ratio of the ethylene-vinyl acetate copolymer to the terminal hydroxyl polybutadiene rubber is 1:6 to 6:

1.

2. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that The material of the conductor is copper.

3. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that The insulating layer is a cross-linked polyethylene insulating layer.

4. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that The mass ratio of the ethylene-vinyl acetate copolymer to the hydroxyl-terminated polybutadiene rubber is 5-6:

1.

5. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that The Vicat softening temperature of the ethylene-vinyl acetate copolymer is 76-88.3°C.

6. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that The plasticizer includes one or more of dioctyl phthalate, dioctyl terephthalate, and dioctyl sebacate.

7. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that The antioxidant includes one or more of antioxidant 1010 , antioxidant 1076 , and antioxidant 626 .

8. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that The light stabilizer includes one or more of Tinuvin 770, Chimassorb 944, and Hostavin N30.

9. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that The talcum powder is modified talcum powder, the modifier of the modified talcum powder is polybutyl acrylate, and the mass ratio of the polybutyl acrylate to the talcum powder is 3-4:

20.

10. A highly weather-resistant photovoltaic cable according to claim 1, It is characterized in that Also includes at least one of the following technical features: The flame retardant includes one or more of aluminum hydroxide, magnesium hydroxide, and antimony trioxide; The cross-linking agent includes one or more of dicumyl peroxide, benzoyl peroxide, and di-tert-butyl peroxide.

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