Shielding type fireproof flame-retardant solar photovoltaic cable

Abstract

The invention discloses a shielding type fireproof flame-retardant solar photovoltaic cable, and belongs to the field of cables. The cable comprises a conductor, an insulating layer wrapping the outer layer of the conductor, a shielding layer wrapping the outer layer of the insulating layer and a sheath layer wrapping the outer layer of the shielding layer, and the sheath layer comprises crosslinked polyethylene, a fireproof flame retardant, polyether-ether-ketone and 2, 6-di-tert-butyl-4-methylphenol; the shielding layer is of a double-layer structure, and the inner layer and the outer layer are formed by weaving copper wires and tin wires. And the insulating layer comprises crosslinked polyethylene, tricresyl phosphate and zinc oxide. The fireproof flame retardant is added into the sheath layer, so that the fireproof flame retardant performance of the photovoltaic cable can be improved, the fireproof flame retardant performance of the sheath layer can be improved through lignin and triethyl phosphate, and when the photovoltaic cable is in a high-temperature environment, aluminum trihydrate and ammonium bicarbonate are decomposed to generate moisture, so that the flame retardant performance of the photovoltaic cable is improved. Therefore, the surface temperature of the photovoltaic cable is reduced, the combustion of the photovoltaic cable is inhibited, and the generation of smoke is inhibited.

Description

Technical Field

[0001] The invention relates to a cable, in particular to a shielded fireproof and flame-retardant solar photovoltaic cable. Background Art

[0002] Photovoltaic cable is a cable specially used for power transmission in the DC side circuit of solar photovoltaic power station system. When facing extreme conditions such as high temperature and fire, the fire retardant performance and electromagnetic shielding effect of traditional photovoltaic cables often cannot meet the actual needs. Although there are some photovoltaic cable products claiming to have fire retardant functions on the market, these products still have some problems in practical applications. On the one hand, the fire retardant layer of these products is usually composed of a single fireproof material, such as a ceramic silicone fire-resistant layer. Although these materials can improve the fire resistance of the cable to a certain extent, the fireproof effect is not ideal. On the other hand, in terms of electromagnetic shielding, traditional photovoltaic cables usually lack an effective shielding layer. Therefore, in an environment with strong electromagnetic interference, induced current is prone to occur, which affects the normal operation of photovoltaic equipment, and even seriously causes damage to photovoltaic equipment. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a shielded fire-retardant solar photovoltaic cable.

[0004] Technical solution: A shielded fire-retardant solar photovoltaic cable, including a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer, the sheath layer including cross-linked polyethylene, fire retardant, polyetheretherketone, 2,6-di-tert-butyl-4-methylphenol; the shielding layer is a double-layer structure, and the inner and outer layers are woven from copper wire and tin wire; the insulating layer includes cross-linked polyethylene, tricresyl phosphate, and zinc oxide.

[0005] Preferably, the sheath layer specifically comprises the following components in percentage by weight: 70-80% cross-linked polyethylene, 8-13% fire retardant, 6-9% polyetheretherketone, and 4-7% 2,6-di-tert-butyl-4-methylphenol.

[0006] Preferably, the insulating layer specifically comprises the following components in percentage by weight: 70-80% cross-linked polyethylene, 10-15% tricresyl phosphate, and 5-8% zinc oxide.

[0007] Preferably, the fire retardant comprises triethyl phosphate, lignin, aluminum trihydrate, ammonium bicarbonate, and magnesium; and the preparation method thereof is: (1) dissolving lignin in ethanol and performing homogenization to form a lignin solution; (2) adding triethyl phosphate to the lignin solution, and then adding dibenzoyl peroxide to the solution, and stirring at 500-800 rpm at 35-45°C for 15-20 minutes; (3) adding aluminum trihydrate, ammonium bicarbonate and magnesium to the solution in step (2), and stirring at 200-300 rpm for 5-10 minutes; (4) Finally, the product obtained in step (3) is filtered to obtain a filter residue and a filtrate, and then the filter residue is dried at 50-70° C., and then crushed and sieved to obtain a fire retardant.

[0008] Preferably, in step (2), triethyl phosphate: lignin solution: dibenzoyl peroxide (W / W / W) = (3-5): (1-2): (2-3); in step (3), aluminum trihydrate: ammonium bicarbonate: magnesium (W / W / W) = (2-4): (1-3): (1-3).

[0009] Preferably, in step (4), the crushed filter residue is sieved through a 50-100 mesh sieve to obtain a fire retardant.

[0010] Preferably, the preparation method of the tin wire in the shielding layer is: melting the metallic tin to form a tin melt, then adding neodymium magnetic powder in a weight ratio of 1:0.5-0.8 to the tin melt, homogenizing, cooling to form a tin solid, and then obtaining the required tin wire after a wire drawing operation.

[0011] Preferably, the method for making the shielding layer is as follows: first, copper wire and tin wire are twisted together in a 1:1 ratio in a clockwise direction to form a copper-tin twisted pair wire one, and then the copper-tin twisted pair wire one is spirally woven clockwise along the axis of the conductor on the outside of the conductor to form a shielding inner layer; then, copper wire and tin wire are twisted together in a 1:1 ratio in a counterclockwise direction to form a copper-tin twisted pair wire two, and then the copper-tin twisted pair wire two is spirally woven counterclockwise along the axis of the conductor on the outside of the shielding inner layer to form a shielding outer layer, and finally a shielding layer can be formed on the outer layer of the conductor.

[0012] Beneficial effects: (1) The present invention adds a fire retardant to the sheath layer to improve the fire retardant performance of the photovoltaic cable. The fire retardant performance of the sheath layer can be improved by lignin and triethyl phosphate. When the photovoltaic cable is in a high temperature environment, aluminum trihydrate and ammonium bicarbonate decompose to produce moisture, thereby reducing the surface temperature of the photovoltaic cable, inhibiting the combustion of the photovoltaic cable, and inhibiting the generation of smoke. In addition, the ammonia and carbon dioxide produced by the decomposition of ammonium bicarbonate will reduce the concentration of oxygen in the surrounding air, thereby further preventing the combustion of the photovoltaic cable. At the same time, the generated carbon dioxide will react with magnesium to generate magnesium oxide and carbon. The generated magnesium oxide and carbon will fill the defects such as cracks and cavities on the surface of the sheath caused by high temperature, thereby improving the compactness of the sheath and further preventing the combustion of the photovoltaic cable.

[0013] (2) The present invention adds a shielding layer between the insulating layer and the sheath layer. The double-layer shielding layer made by special weaving methods of copper wire and tin wire treated with neodymium magnetic powder can better prevent the occurrence of electromagnetic interference, thereby enabling the photovoltaic cable to work in a stable environment and avoiding the situation in which induced current is easily generated in the photovoltaic cable in an environment with strong electromagnetic interference, thereby affecting the normal operation of the photovoltaic equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the cable of the present invention. DETAILED DESCRIPTION

[0015] In order to make the technical solution of the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] Example 1 A shielded fire-retardant solar photovoltaic cable comprises a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer. Figure 1 shown.

[0017] The sheath layer includes the following components in percentage by weight: 70% of cross-linked polyethylene, 8% of fire retardant, 6% of polyetheretherketone, and 4% of 2,6-di-tert-butyl-4-methylphenol.

[0018] The fire retardant comprises triethyl phosphate, lignin, aluminum trihydrate, ammonium bicarbonate and magnesium; and the preparation method thereof is as follows: (1) dissolving lignin in ethanol and performing homogenization to form a lignin solution; (2) Add triethyl phosphate to the lignin solution, and then add dibenzoyl peroxide to the solution, triethyl phosphate: lignin solution: dibenzoyl peroxide (W / W / W) = 3:1:2, and stir at 35°C and 500 rpm for 15 min; (3) Add aluminum trihydrate, ammonium bicarbonate and magnesium to the solution in step (2), with aluminum trihydrate: ammonium bicarbonate: magnesium (W / W / W) = 2:1:1, and stir at 200 rpm for 5 min; (4) Finally, the product obtained in step (3) is filtered to obtain a filter residue and a filtrate, and the filter residue is then dried at 50° C., crushed, and passed through a 50-mesh sieve to obtain a fire retardant.

[0019] The shielding layer has a double-layer structure. The copper wire and the tin wire are first twisted in a clockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire one, and then the copper-tin twisted pair wire one is spirally woven clockwise along the axis of the conductor on the outside of the conductor to form a shielding inner layer; then the copper wire and the tin wire are twisted in a counterclockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire two, and then the copper-tin twisted pair wire two is spirally woven counterclockwise along the axis of the conductor on the outside of the shielding inner layer to form a shielding outer layer, and finally a shielding layer can be formed on the outer layer of the conductor.

[0020] Among them, the preparation method of tin wire is: melt the metal tin to form a tin melt, then add neodymium magnetic powder with a weight ratio of 1:0.5 into the tin melt, after homogenization, cool to form a tin solid, and then after wire drawing operation, obtain the required tin wire.

[0021] The insulating layer includes the following components by weight: 70% cross-linked polyethylene, 10% tricresyl phosphate, and 5% zinc oxide.

[0022] Example 2 A shielded fire-retardant solar photovoltaic cable comprises a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer. Figure 1 shown.

[0023] The sheath layer comprises the following components in percentage by weight: 75% of cross-linked polyethylene, 10% of fire retardant, 7% of polyetheretherketone, and 6% of 2,6-di-tert-butyl-4-methylphenol.

[0024] The fire retardant comprises triethyl phosphate, lignin, aluminum trihydrate, ammonium bicarbonate and magnesium; and the preparation method thereof is as follows: (1) dissolving lignin in ethanol and performing homogenization to form a lignin solution; (2) Add triethyl phosphate to the lignin solution, and then add dibenzoyl peroxide to the solution, triethyl phosphate: lignin solution: dibenzoyl peroxide (W / W / W) = 4:1:3, and stir at 40°C and 650 rpm for 17 min; (3) Add aluminum trihydrate, ammonium bicarbonate and magnesium to the solution in step (2), with the ratio of aluminum trihydrate: ammonium bicarbonate: magnesium (W / W / W) = 3:2:1, and stir at 300 rpm for 8 min; (4) Finally, the product obtained in step (3) is filtered to obtain a filter residue and a filtrate, and the filter residue is then dried at 60° C., crushed, and passed through an 80-mesh sieve to obtain a fire retardant.

[0025] The shielding layer has a double-layer structure. The copper wire and the tin wire are first twisted in a clockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire one, and then the copper-tin twisted pair wire one is spirally woven clockwise along the axis of the conductor on the outside of the conductor to form a shielding inner layer; then the copper wire and the tin wire are twisted in a counterclockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire two, and then the copper-tin twisted pair wire two is spirally woven counterclockwise along the axis of the conductor on the outside of the shielding inner layer to form a shielding outer layer, and finally a shielding layer can be formed on the outer layer of the conductor.

[0026] Among them, the preparation method of tin wire is: melt the metal tin to form a tin melt, then add neodymium magnetic powder with a weight ratio of 1:0.7 into the tin melt, after homogenization, cool to form a tin solid, and then after wire drawing operation, obtain the required tin wire.

[0027] The insulating layer includes the following components by weight: 75% cross-linked polyethylene, 13% tricresyl phosphate, and 7% zinc oxide.

[0028] Example 3 A shielded fire-retardant solar photovoltaic cable comprises a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer. Figure 1 shown.

[0029] The sheath layer comprises the following components by weight percentage: 80% of cross-linked polyethylene, 13% of fire retardant, 9% of polyetheretherketone, and 7% of 2,6-di-tert-butyl-4-methylphenol.

[0030] The fire retardant comprises triethyl phosphate, lignin, aluminum trihydrate, ammonium bicarbonate and magnesium; and the preparation method thereof is as follows: (1) dissolving lignin in ethanol and performing homogenization to form a lignin solution; (2) Add triethyl phosphate to the lignin solution, and then add dibenzoyl peroxide to the solution, triethyl phosphate: lignin solution: dibenzoyl peroxide (W / W / W) = 5:2:3, and stir at 45 °C and 800 rpm for 20 min; (3) Add aluminum trihydrate, ammonium bicarbonate and magnesium to the solution in step (2), with aluminum trihydrate: ammonium bicarbonate: magnesium (W / W / W) = 4:3:3, and stir at 300 rpm for 10 min; (4) Finally, the product obtained in step (3) is filtered to obtain a filter residue and a filtrate, and the filter residue is then dried at 70° C., crushed, and passed through a 100-mesh sieve to obtain a fire retardant.

[0031] The shielding layer has a double-layer structure. The copper wire and the tin wire are first twisted in a clockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire one, and then the copper-tin twisted pair wire one is spirally woven clockwise along the axis of the conductor on the outside of the conductor to form a shielding inner layer; then the copper wire and the tin wire are twisted in a counterclockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire two, and then the copper-tin twisted pair wire two is spirally woven counterclockwise along the axis of the conductor on the outside of the shielding inner layer to form a shielding outer layer, and finally a shielding layer can be formed on the outer layer of the conductor.

[0032] Among them, the preparation method of tin wire is: melt the metal tin to form a tin melt, then add neodymium magnetic powder with a weight ratio of 1:0.8 into the tin melt, after homogenization, cool to form a tin solid, and then after wire drawing operation, obtain the required tin wire.

[0033] The insulating layer includes the following components by weight: 80% cross-linked polyethylene, 15% tricresyl phosphate, and 8% zinc oxide.

[0034] Comparative Example 1 A shielded fireproof and flame-retardant solar photovoltaic cable comprises a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer.

[0035] The sheath layer comprises the following components in weight percentage: 80% of cross-linked polyethylene, 9% of polyetheretherketone, and 7% of 2,6-di-tert-butyl-4-methylphenol.

[0036] The shielding layer has a double-layer structure. The copper wire and the tin wire are first twisted in a clockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire one, and then the copper-tin twisted pair wire one is spirally woven clockwise along the axis of the conductor on the outside of the conductor to form a shielding inner layer; then the copper wire and the tin wire are twisted in a counterclockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire two, and then the copper-tin twisted pair wire two is spirally woven counterclockwise along the axis of the conductor on the outside of the shielding inner layer to form a shielding outer layer, and finally a shielding layer can be formed on the outer layer of the conductor.

[0037] Among them, the preparation method of tin wire is: melt the metal tin to form a tin melt, then add neodymium magnetic powder with a weight ratio of 1:0.8 into the tin melt, after homogenization, cool to form a tin solid, and then after wire drawing operation, obtain the required tin wire.

[0038] The insulating layer includes the following components by weight: 80% cross-linked polyethylene, 15% tricresyl phosphate, and 8% zinc oxide.

[0039] Comparative Example 2 A shielded fireproof and flame-retardant solar photovoltaic cable comprises a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer.

[0040] The sheath layer comprises the following components by weight percentage: 80% of cross-linked polyethylene, 13% of fire retardant, 9% of polyetheretherketone, and 7% of 2,6-di-tert-butyl-4-methylphenol.

[0041] Wherein, the fire retardant comprises triethyl phosphate and lignin; and the preparation method thereof is as follows: (1) dissolving lignin in ethanol and performing homogenization to form a lignin solution; (2) Add triethyl phosphate to the lignin solution, and then add dibenzoyl peroxide to the solution, triethyl phosphate: lignin solution: dibenzoyl peroxide (W / W / W) = 5:2:3, and stir at 45 °C and 800 rpm for 20 min; (3) Finally, the product obtained in step (2) is filtered to obtain a filter residue and a filtrate, and the filter residue is then dried at 70° C., crushed, and passed through a 100-mesh sieve to obtain a fire retardant.

[0042] The shielding layer has a double-layer structure. The copper wire and the tin wire are first twisted in a clockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire one, and then the copper-tin twisted pair wire one is spirally woven clockwise along the axis of the conductor on the outside of the conductor to form a shielding inner layer; then the copper wire and the tin wire are twisted in a counterclockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire two, and then the copper-tin twisted pair wire two is spirally woven counterclockwise along the axis of the conductor on the outside of the shielding inner layer to form a shielding outer layer, and finally a shielding layer can be formed on the outer layer of the conductor.

[0043] Among them, the preparation method of tin wire is: melt the metal tin to form a tin melt, then add neodymium magnetic powder with a weight ratio of 1:0.8 into the tin melt, after homogenization, cool to form a tin solid, and then after wire drawing operation, obtain the required tin wire.

[0044] The insulating layer includes the following components by weight: 80% cross-linked polyethylene, 15% tricresyl phosphate, and 8% zinc oxide.

[0045] Comparative Example 3 A shielded fireproof and flame-retardant solar photovoltaic cable comprises a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer.

[0046] The sheath layer includes the following components by weight: 80% of cross-linked polyethylene, 13% of silicon dioxide, 9% of polyetheretherketone, and 7% of 2,6-di-tert-butyl-4-methylphenol.

[0047] The shielding layer has a double-layer structure. The copper wire and the tin wire are first twisted in a clockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire one, and then the copper-tin twisted pair wire one is spirally woven clockwise along the axis of the conductor on the outside of the conductor to form a shielding inner layer; then the copper wire and the tin wire are twisted in a counterclockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire two, and then the copper-tin twisted pair wire two is spirally woven counterclockwise along the axis of the conductor on the outside of the shielding inner layer to form a shielding outer layer, and finally a shielding layer can be formed on the outer layer of the conductor.

[0048] Among them, the preparation method of tin wire is: melt the metal tin to form a tin melt, then add neodymium magnetic powder with a weight ratio of 1:0.8 into the tin melt, after homogenization, cool to form a tin solid, and then after wire drawing operation, obtain the required tin wire.

[0049] The insulating layer includes the following components by weight: 80% cross-linked polyethylene, 15% tricresyl phosphate, and 8% zinc oxide.

[0050] Comparative Example 4 A shielded fireproof and flame-retardant solar photovoltaic cable comprises a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer.

[0051] The sheath layer comprises the following components by weight percentage: 80% of cross-linked polyethylene, 13% of fire retardant, 9% of polyetheretherketone, and 7% of 2,6-di-tert-butyl-4-methylphenol.

[0052] The fire retardant comprises triethyl phosphate, lignin, aluminum trihydrate, ammonium bicarbonate and magnesium; and the preparation method thereof is as follows: (1) dissolving lignin in ethanol and performing homogenization to form a lignin solution; (2) Add triethyl phosphate to the lignin solution, and then add dibenzoyl peroxide to the solution, triethyl phosphate: lignin solution: dibenzoyl peroxide (W / W / W) = 5:2:3, and stir at 45 °C and 800 rpm for 20 min; (3) Add aluminum trihydrate, ammonium bicarbonate and magnesium to the solution in step (2), with aluminum trihydrate: ammonium bicarbonate: magnesium (W / W / W) = 4:3:3, and stir at 300 rpm for 10 min; (4) Finally, the product obtained in step (3) is filtered to obtain a filter residue and a filtrate, and the filter residue is then dried at 70° C., crushed, and passed through a 100-mesh sieve to obtain a fire retardant.

[0053] The shielding layer is formed by copper wires being cross-woven on the outside of the conductor along the axis of the conductor.

[0054] Among them, the preparation method of tin wire is: melt the metal tin to form a tin melt, then add neodymium magnetic powder with a weight ratio of 1:0.8 into the tin melt, after homogenization, cool to form a tin solid, and then after wire drawing operation, obtain the required tin wire.

[0055] The insulating layer includes the following components by weight: 80% cross-linked polyethylene, 15% tricresyl phosphate, and 8% zinc oxide.

[0056] Photovoltaic cable performance testing: The photovoltaic cables obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were subjected to GB / T 19666 standard, and the self-extinguishing time of each photovoltaic cable was recorded after the flame was removed under the condition of flame (200° C.) burning for a specified time (15 min).

[0057] The photovoltaic cables obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were subjected to GB / T 17651 standard, and the smoke generated by burning each photovoltaic cable was projected with light when burning at 200° C., and the light transmittance of the smoke generated by burning each photovoltaic cable was recorded.

[0058] The photovoltaic cables obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were subjected to a shielding performance test according to the GJB 6190-2008 standard, thereby obtaining the shielding effectiveness of each photovoltaic cable.

[0059] The test results are shown in the following table.

[0060]

[0061] It can be seen that the photovoltaic cable prepared by the present invention has good fire retardant performance, and can avoid violent combustion in a high temperature environment. In addition, the photovoltaic cable prepared by the present invention has good anti-electromagnetic interference performance, and can work normally in an environment with strong electromagnetic interference, avoiding the induction of a large current inside the cable in an environment with strong electromagnetic interference, thereby causing the photovoltaic device to fail to work properly, or even causing damage to the photovoltaic device.

[0062] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A shielded fire-retardant solar photovoltaic cable, comprising a conductor, an insulating layer wrapped around the outer layer of the conductor, a shielding layer wrapped around the outer layer of the insulating layer, and a sheath layer wrapped around the outer layer of the shielding layer, characterized in that: The sheath layer includes cross-linked polyethylene, fire retardant, polyetheretherketone, and 2,6-di-tert-butyl-4-methylphenol; the shielding layer is a double-layer structure, and the inner and outer layers are woven from copper wire and tin wire; the insulating layer includes cross-linked polyethylene, tricresyl phosphate, and zinc oxide.

2. The shielded fire-retardant solar photovoltaic cable according to claim 1, characterized in that: The sheath layer specifically comprises the following components by weight percentage: 70-80% of cross-linked polyethylene, 8-13% of fire retardant, 6-9% of polyetheretherketone, and 4-7% of 2,6-di-tert-butyl-4-methylphenol.

3. The shielded fire-retardant solar photovoltaic cable according to claim 1, characterized in that: The insulating layer specifically comprises the following components in percentage by weight: 70-80% of cross-linked polyethylene, 10-15% of tricresyl phosphate, and 5-8% of zinc oxide.

4. The shielded fire-retardant solar photovoltaic cable according to claim 1, characterized in that: The fire retardant comprises triethyl phosphate, lignin, aluminum trihydrate, ammonium bicarbonate and magnesium; and the preparation method thereof is as follows: (1) dissolving lignin in ethanol and performing homogenization to form a lignin solution; (2) adding triethyl phosphate to the lignin solution, and then adding dibenzoyl peroxide to the solution, and stirring at 500-800 rpm at 35-45°C for 15-20 minutes; (3) adding aluminum trihydrate, ammonium bicarbonate and magnesium to the solution in step (2), and stirring at 200-300 rpm for 5-10 minutes; (4) Finally, the product obtained in step (3) is filtered to obtain a filter residue and a filtrate, and then the filter residue is dried at 50-70° C., and then crushed and sieved to obtain a fire retardant.

5. The shielded fire-retardant solar photovoltaic cable according to claim 4, characterized in that: In step (2), triethyl phosphate: lignin solution: dibenzoyl peroxide (W / W / W) = (3-5): (1-2): (2-3); in step (3), aluminum trihydrate: ammonium bicarbonate: magnesium (W / W / W) = (2-4): (1-3): (1-3).

6. The shielded fire-retardant solar photovoltaic cable according to claim 1, characterized in that: In step (4), the crushed filter residue is sieved through a 50-100 mesh sieve to obtain a fire retardant.

7. The shielded fire-retardant solar photovoltaic cable according to claim 1, characterized in that: The preparation method of the tin wire in the shielding layer is as follows: melt the metal tin to form a tin melt, then add neodymium magnetic powder in a weight ratio of 1:0.5-0.8 to the tin melt, homogenize it, cool it to form a tin solid, and then obtain the required tin wire after wire drawing.

8. The shielded fire-retardant solar photovoltaic cable according to claim 1, characterized in that: The manufacturing method of the shielding layer is as follows: firstly, the copper wire and the tin wire are twisted in a clockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire one, and then the copper-tin twisted pair wire one is spirally woven clockwise along the axis of the conductor on the outside of the conductor to form a shielding inner layer; then, the copper wire and the tin wire are twisted in a counterclockwise direction in a ratio of 1:1 to form a copper-tin twisted pair wire two, and then the copper-tin twisted pair wire two is spirally woven counterclockwise along the axis of the conductor on the outside of the shielding inner layer to form a shielding outer layer, and finally a shielding layer can be formed on the outer layer of the conductor.

Images