Flame-retardant anti-bite power cable for photovoltaic power station
By employing a multi-layer structure and a combination of a self-healing functional layer and an anti-bite armor layer in the cables used in photovoltaic power plants, the problems of insufficient flame retardancy and lack of anti-bite performance are solved, achieving highly efficient flame retardancy and anti-bite effects for the cables, and providing self-healing and early warning functions.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG LANTIAN CABLES MFG
- Filing Date
- 2026-04-29
- Publication Date
- 2026-05-29
AI Technical Summary
Existing photovoltaic power station cables have insufficient flame retardant properties, are easily combustible and produce dense smoke and toxic gases, and lack anti-bite performance, which cannot effectively prevent the spread of fire. Single metal armor is heavy, has poor flexibility, and the chemical repellency effect has a short duration and lacks a biting warning function.
The structure is designed from the inside out, including a conductor, an insulation layer, a self-healing functional layer, a buffer water-blocking layer, an inner lining layer, an anti-bite armor layer, a high-strength oxygen-barrier binding layer, a flame-retardant protective layer, and an outer sheath layer. By combining the self-healing functional layer and the anti-bite armor layer with irritant repellent capsules and multiple layers of flame-retardant materials, multiple fire barriers and physical and chemical repellency mechanisms are formed.
It achieves excellent flame retardant effect and anti-bite performance of the cable. The self-healing functional layer can actively heal micro-cracks, the anti-bite armor layer provides immediate stimulation and repulsion, and the multi-layer structure forms a four-fold fire barrier. The cable combustion test reaches B1 level and has a biting warning function.
Smart Images
Figure CN122117552A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a power cable, and more particularly to a flame-retardant and bite-resistant power cable for photovoltaic power plants. Background Technology
[0002] With the rapid popularization of photovoltaic power generation technology, a large number of photovoltaic power stations are being built in forests, wastelands, rooftops, and areas where agriculture and photovoltaics complement each other. In these environments, rodents such as rats and ants are frequently active, and the outer sheath of ordinary cables is difficult to protect against their continuous gnawing. Once the insulation layer is damaged, it can easily lead to leakage, short circuits, or even fires, seriously threatening the safe operation of the power station and the stability of the power grid.
[0003] Existing anti-bite cables have the following shortcomings: First, their flame-retardant performance is insufficient. Most cables use a single flame-retardant material, which easily produces a large amount of dense smoke and toxic gases when burning, failing to effectively prevent the spread of fire. Once a fire occurs, it will cause serious equipment damage and economic losses. Second, their anti-bite performance is inadequate. Existing anti-bite cables mostly use a single metal armor or a single chemical repellency method. Single metal armor has the problems of being heavy, having poor flexibility, and being easily bitten and damaged in some areas. The repellency effect of single chemical repellency methods is short-lasting, and the repellent is easily lost after long-term outdoor use, failing to achieve long-term anti-bite protection. Furthermore, they lack a biting warning function, making it impossible to detect potential damage in a timely manner. Therefore, existing technologies suffer from poor flame retardant and anti-bite effects. Summary of the Invention
[0004] The purpose of this invention is to provide a flame-retardant and anti-bite power cable for photovoltaic power plants. This invention effectively improves both flame-retardant and anti-bite properties.
[0005] The technical solution of this invention: A flame-retardant and bite-resistant power cable for photovoltaic power stations, comprising, from the inside out, a conductor, an insulation layer, a self-healing functional layer, a buffer water-blocking layer, an inner lining layer, a bite-resistant armor layer, a high-strength oxygen-barrier binding layer, a flame-retardant protective layer, and an outer sheath layer; the self-healing functional layer includes a matrix material, which is filled with repair agent microcapsules and catalyst microcapsules; the bite-resistant armor layer is filled with an irritant-repellent capsule coating.
[0006] In the aforementioned flame-retardant and bite-resistant photovoltaic power cable, the matrix material is ethylene-vinyl acetate copolymer, with an addition amount of 90-110 parts by weight; the amount of repair agent microcapsules is 10-15 parts by weight, and the amount of catalyst microcapsules is 2-5 parts by weight.
[0007] In the aforementioned flame-retardant and bite-resistant photovoltaic power cable, the repair agent microcapsules use urea-formaldehyde resin as the wall material and dicyclopentadiene monomer as the core material, with a microcapsule particle size of 5-20 μm; the catalyst microcapsules use urea-formaldehyde resin as the wall material and Grubb catalyst as the core material, with a microcapsule particle size of 5-20 μm.
[0008] In the aforementioned flame-retardant and bite-resistant power cable for photovoltaic power stations, the insulation layer is made of polyolefin insulation material; the buffer water-blocking layer is made of non-woven fabric with super absorbent resin powder adhering to it; and the inner lining layer is made of ceramicized silicone rubber composite tape.
[0009] In the aforementioned flame-retardant and bite-resistant power cable for photovoltaic power stations, the bite-resistant armor layer comprises a spirally wound aluminum alloy strip, the surface of which is provided with an array of diamond-shaped microgrooves, and the diamond-shaped microgrooves are filled with an irritant-repellent capsule coating; the capsules in the irritant-repellent capsule coating use β-cyclodextrin as the wall material, and the core material is filled with capsaicin and denatamine, the mass ratio of capsaicin to denatamine is 1:0.3-0.5.
[0010] In the aforementioned flame-retardant and bite-resistant photovoltaic power cable, the high-strength oxygen-barrier binding layer is glass fiber reinforced polyester tape.
[0011] In the aforementioned flame-retardant and bite-resistant photovoltaic power cable, the flame-retardant protective layer is composed of a flame-retardant coating, which contains the following components in parts by weight: ethylene-vinyl acetate copolymer, 40-60 parts; linear low-density polyethylene, 15-25 parts; ammonium polyphosphate, 20-30 parts; pentaerythritol, 8-15 parts; melamine, 5-10 parts; nano-montmorillonite, 3-8 parts; compatibilizer, 5-10 parts; antioxidant, 1-2 parts.
[0012] In the aforementioned flame-retardant and bite-resistant photovoltaic power cable, a set of ring-shaped triangular cross-section support ribs are formed on the outer surface of the flame-retardant protective layer.
[0013] In the aforementioned flame-retardant and bite-resistant power cable for photovoltaic power stations, the outer sheath is made of halogen-free, low-smoke, flame-retardant polyolefin sheath material, which contains 2%-5% by mass of reversible thermochromic microcapsules.
[0014] Compared with existing technologies, this invention comprises, from the inside out, a conductor, an insulation layer, a self-healing functional layer, a buffer water-blocking layer, an inner lining layer, an anti-bite armor layer, a high-strength oxygen-barrier binding layer, a flame-retardant protective layer, and an outer sheath layer. These layers work together to give the power cable excellent flame-retardant and anti-bite properties. Specifically, 1) The anti-bite armor layer of this application consists of an aluminum alloy strip with an array of diamond-shaped microgrooves and an irritant-repellent capsule coating on its surface. While achieving weight reduction, it also has the dual functions of physical barrier and chemical repellency. The aluminum alloy provides high-strength mechanical protection, and the surface microgroove array utilizes the principle of mechanical mismatch to prevent rodents from "biting or exerting force"; the sustained-release microcapsules, a combination of capsaicin and denatamine, are precisely released under the action of biting force, triggering both immediate stimulation and memory aversion as a dual repellency.
[0015] 2) The self-healing functional layer and the anti-bite armor layer form a complete damage management closed loop; even if individual rodents and ants overcome the repellent stimulation and bypass the mechanical mismatch of the microgrooves, successfully leave tentative bite marks on the surface of the armor layer and cause micro-cracks in the insulation layer, the self-healing layer can still actively heal the cracks before they extend to the conductor, transforming "post-fault repair" into "self-healing maintenance".
[0016] 3) The inner lining layer works in conjunction with the flame-retardant protective layer. The ceramicized silicone rubber of the inner lining forms a shell for heat insulation when exposed to fire, the flame-retardant protective layer expands into carbon to isolate oxygen, and the insulation / sheath layer is halogen-free, flame-retardant, and low-smoke. Combined with the high-strength oxygen-barrier binding layer to seal the gaps in the armor, a four-fold fire barrier of "ceramic shell - expanded carbon layer - flame-retardant polyolefin - oxygen-barrier binding" is formed. The cable bundle combustion test can reach B1 level.
[0017] In summary, the present invention can effectively improve the flame retardant effect and the anti-bite effect through the cooperation between the above structures. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a structural view of the anti-bite armor layer.
[0019] The labels in the attached diagram are: 1-conductor, 2-insulation layer, 3-self-healing functional layer, 4-buffered water-blocking layer, 5-inner lining layer, 6-anti-bite armor layer, 7-high-strength oxygen-barrier binding layer, 8-flame-retardant protective layer, 9-outer sheath layer, 61-aluminum alloy strip, 62-diamond microgroove, 63-irritant repellent capsule coating. Detailed Implementation
[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.
[0021] Example. A flame-retardant and bite-resistant power cable for a photovoltaic power station, comprising as follows: Figure 1As shown, the structure, from the inside out, comprises a conductor 1, an insulating layer 2, a self-healing functional layer 3, a buffer water-blocking layer 4, an inner lining layer 5, an anti-bite armor layer 6, a high-strength oxygen-barrier binding layer 7, a flame-retardant protective layer 8, and an outer sheath layer 9. The self-healing functional layer includes a matrix material filled with repair agent microcapsules and catalyst microcapsules. The anti-bite armor layer 6 is filled with an irritant-repellent capsule coating.
[0022] The conductor is a tin-plated copper conductor, composed of multiple strands of fine tin-plated copper wire twisted together, with the twist ratio controlled at 10-14 times. This structure ensures excellent conductivity and flexibility, adapting to the bending installation requirements of the confined spaces in photovoltaic power plants.
[0023] The high-strength oxygen-barrier binding layer is made of glass fiber reinforced polyester tape.
[0024] The matrix material is ethylene-vinyl acetate copolymer, and the addition amount is 90-110 parts by weight; the addition amount of repair agent microcapsules is 10-15 parts by weight, and the addition amount of catalyst microcapsules is 2-5 parts by weight.
[0025] The repair agent microcapsules use urea-formaldehyde resin as the wall material and dicyclopentadiene monomer as the core material, with a microcapsule particle size of 5-20 μm; the catalyst microcapsules use urea-formaldehyde resin as the wall material and Grubb catalyst as the core material, with a microcapsule particle size of 5-20 μm.
[0026] Preferably, the self-healing functional layer material is prepared from the following components in parts by weight: 100 parts EVA (VA content 22%), 12 parts repair agent microcapsules (urea-formaldehyde resin coated with dicyclopentadiene, particle size 10 μm), 3 parts catalyst microcapsules (urea-formaldehyde resin coated with Grubb catalyst solid dispersion, particle size 10 μm), and 4 parts liquid paraffin. After being blended and granulated using a twin-screw extruder, the components are simultaneously extruded with the insulating layer through a co-extrusion die.
[0027] The insulation layer 2 is a polyolefin insulation material; the buffer water-blocking layer 4 is made of non-woven fabric with super absorbent resin powder adhering to it; the inner lining layer 5 is made of ceramicized silicone rubber composite tape.
[0028] like Figure 2 As shown, the anti-bite armor layer 6 includes a spirally wound aluminum alloy strip 61. The surface of the aluminum alloy strip 61 is provided with an array of diamond-shaped microgrooves 62. The diamond-shaped microgrooves 62 are filled with an irritant-repellent capsule coating 63. The capsules in the irritant-repellent capsule coating have β-cyclodextrin as the wall material and the core material is filled with capsaicin and denatamine. The mass ratio of capsaicin to denatamine is 1:0.3-0.5.
[0029] Preferably, the grooves have a depth of 50 μm, a spacing of 150 μm, and an edge angle of 75°. The microgrooves are filled with a sustained-release microcapsule coating of capsaicin and denaphalonamine, with a coating thickness of 35 μm. The mass ratio of capsaicin to denaphalonamine in the core material is 1:0.4. The microcapsules are prepared using β-cyclodextrin as the wall material via a saturated aqueous solution method.
[0030] The flame-retardant protective layer is composed of a flame-retardant coating of an intumescent halogen-free flame-retardant polyolefin material, which contains the following components in parts by weight: ethylene-vinyl acetate copolymer (EVA, VA content 28%), 40-60 parts; linear low-density polyethylene, 15-25 parts; ammonium polyphosphate, 20-30 parts; pentaerythritol, 8-15 parts; melamine, 5-10 parts; nano-montmorillonite, 3-8 parts; compatibilizer, 5-10 parts; antioxidant, 1-2 parts.
[0031] As a preferred embodiment, the specific formulation of the flame-retardant protective layer is (by weight): 50 parts EVA (VA content 28%), 20 parts LLDPE, 25 parts APP, 12 parts PER, 8 parts MEL, 5 parts nano-montmorillonite, 8 parts maleic anhydride-grafted EVA compatibilizer, and 1.5 parts antioxidant 1010. All components are mixed in an internal mixer, granulated by twin-screw extrusion, and then coated onto the outer layer of the binding layer using an extruder.
[0032] When exposed to fire, this material catalyzes the carbonization of pentaerythritol using ammonium polyphosphate and foams melamine, forming an expanded porous char layer with significant heat and oxygen insulation effects. Nano-montmorillonite is dispersed in the matrix in a layered structure, extending the escape path of combustible gases and further enhancing flame retardancy.
[0033] The outer surface of the flame-retardant protective layer 8 has a set of annularly distributed triangular cross-section support ribs. These ribs are formed through co-extrusion molding, creating a triangular cross-section support rib on the outer surface of the inner flame-retardant protective layer, which is then covered by the outer sheath layer, forming an annular array of air cavities. This significantly reduces the heat transfer rate from external high temperatures to the cable's interior; the air cavity structure reduces the overall cable density, lessening the load on the support structure; and the support ribs provide radial compressive stiffness, preventing the outer sheath from collapsing and deforming during wind-induced vibrations.
[0034] The outer sheath is made of halogen-free, low-smoke, flame-retardant polyolefin sheath material, which contains 2%-5% by mass of reversible thermochromic microcapsules.
[0035] As a preferred option, the outer sheath layer is made of 125℃ irradiated crosslinked halogen-free low-smoke flame-retardant polyolefin sheath material (commercially available model HFFR-125UV), with the addition of 0.5% ultraviolet absorber UV-326, 0.3% light stabilizer 770, and 3% reversible thermochromic microcapsules (color change threshold 75℃, crystal violet lactone-bisphenol A-tetradecyl alcohol system, wall material melamine resin).
[0036] The insulation layer is a halogen-free, low-smoke, flame-retardant polyolefin insulation material that is irradiated at 125°C. The polymer molecular chains are formed into a three-dimensional network structure through an electron beam irradiation crosslinking process.
[0037] The self-healing functional layer is located between the insulating layer and the buffer water-blocking layer. This functional layer consists of a matrix material, repair agent microcapsules, and catalyst microcapsules. The matrix material is ethylene-vinyl acetate copolymer (EVA), wherein the vinyl acetate (VA) content is 18%-25%. This matrix material has excellent compatibility with the insulating layer material, ensuring strong interfacial bonding.
[0038] The repair agent microcapsules use urea-formaldehyde resin as the wall material and dicyclopentadiene monomer as the core material. The microcapsule particle size is 5-20 μm, and the addition amount is 10-15 parts by weight.
[0039] The catalyst microcapsules use urea-formaldehyde resin as the wall material and Grubbs catalyst as the core material. The microcapsule particle size is 5-20 μm, and the addition amount is 2-5 parts by weight.
[0040] Preferably, the amount of repair agent microcapsules added is 15 parts, and the amount of catalyst microcapsules added is 5 parts.
[0041] When microcracks develop in the insulation layer due to external force and propagate to the self-healing layer, stress concentration at the crack tip causes the microcapsules to rupture. After releasing the repair agent and catalyst from the microcapsules, they come into contact and mix at the crack surface. Dicyclopentadiene undergoes a ring-opening metathesis polymerization reaction under the action of Grubb catalyst, forming a cross-linked polydicyclopentadiene solid within 10-30 minutes at room temperature, which fills and bonds the crack.
[0042] The self-healing polymerization reaction rate increases with increasing temperature (the reaction rate increases by about 1.5-2 times for every 10°C increase in temperature), achieving positive feedback adaptive adjustment of risk level and repair capability.
[0043] The buffer water-blocking layer is made of a composite tape of non-woven fabric and superabsorbent resin powder. This layer not only buffers mechanical stress, but the superabsorbent resin also expands rapidly upon contact with water to form a gel, blocking the longitudinal penetration of water. Sodium polyacrylate is preferably used as the superabsorbent resin.
[0044] The inner lining layer is made of ceramicized silicone rubber composite tape wrapped around a silicone rubber matrix with ceramicized fillers such as glass powder and mica powder. The ceramicized silicone rubber composite tape is made of silicone rubber matrix with added ceramicized fillers such as glass powder and mica powder. The elongation at break at room temperature is ≥300%. When burned in a flame above 650℃, it can quickly ceramicize to form a dense and hard shell, which can play the role of heat insulation, fireproofing and supporting the armor layer. After being burned at 650℃ for 30 minutes, the flexural strength is ≥15MPa.
[0045] The anti-bite armor layer is made of an aluminum alloy strip spirally wound around its surface. The surface of the aluminum alloy strip is rolled with an array of diamond-shaped microgrooves, with a groove depth of 30-80 μm, a spacing of 100-200 μm, and an edge angle of 60°-90°. This microgroove structure is adapted to rodents, whose incisor cusps have a radius of curvature of approximately 50-100 μm, comparable to the size of the microgrooves. When a bite force is applied along a specific direction, the tooth cusp embeds into the groove and is held in place by the edges on both sides, preventing effective shearing. When the tooth bites perpendicular to the groove direction, the tooth cusp slips and becomes unstable on the smooth edge surface, preventing the bite force from being concentrated. Irritant-repellent microcapsules are filled in the recesses of the diamond-shaped microgrooves to prevent them from being directly scraped off during cable dragging and laying. The rhomboid microgrooves are filled with an irritant-repelling microcapsule coating composed of capsaicin and denaphalonamine. The microcapsules use β-cyclodextrin as the wall material, and the mass ratio of capsaicin to denaphalonamine in the core material is 1:(0.3-0.5).
[0046] When a rodent first bites the cable, the irritant repellent microcapsules rupture, and capsaicin causes instantaneous burning pain in the oral mucosa (immediate repellency); benzodiazepine produces a strong bitter residue, and the rodent forms a taste aversion memory to the cable. Even if the capsaicin odor subsequently weakens due to volatilization, the rodent will still refuse to bite it again due to the bitter memory.
[0047] The high-strength oxygen-barrier binding layer is made of glass fiber reinforced polyester tape, which is wrapped around the outside of the anti-bite armor layer using gap wrapping or overlapping wrapping methods. This prevents the anti-bite armor layer, composed of aluminum alloy tape, from loosening during long-term bending and vibration, ensuring the integrity of the armor structure. Simultaneously, due to the high temperature resistance of the glass fiber reinforced polyester tape, it does not melt or drip when exposed to fire. In the early stages of combustion, it tightly wraps the gaps in the armor layer, preventing external oxygen from entering the cable and supporting the shell-forming reaction of the ceramicized inner lining. It also prevents the leakage of internal pyrolysis combustible gases, significantly improving the cable's vertical self-extinguishing capability.
[0048] The outer sheath layer is a halogen-free, low-smoke, flame-retardant polyolefin sheath material irradiated at 125°C. The sheath material contains ultraviolet absorbers and light stabilizers, which can effectively improve its resistance to ultraviolet aging.
[0049] Furthermore, the outer sheath layer contains 2%-5% by mass of reversible thermochromic microcapsules, with a color-changing temperature threshold set at 75±5℃. The thermochromic microcapsules use crystal violet lactone as the color-developing agent, bisphenol A as the color-developing agent, tetradecyl alcohol as the solvent, and melamine resin as the wall material.
[0050] When the cable is in normal operation, its surface is dark gray or black. When the temperature of the cable exceeds 75°C due to overload or external fire source, the color of the sheath surface will reversibly turn orange-red, providing photovoltaic power plant operation and maintenance personnel with an early visual warning of cable overload or approaching external fire source.
[0051] Preferably, an adhesive layer is provided between the anti-bite armor layer and the inner lining layer, and a conductive fiber mesh is embedded in the adhesive layer. The adhesive layer uses ethylene-vinyl acetate copolymer (EVA) adhesive; the conductive fiber mesh is electrically connected to an external monitoring terminal, and when the metal armor layer is bitten and damaged, the conductive fiber mesh breaks and triggers an early warning signal.
Claims
1. A flame-retardant and bite-resistant power cable for photovoltaic power stations, characterized in that: The structure consists of, from the inside out, a conductor (1), an insulation layer (2), a self-healing functional layer (3), a buffer water-blocking layer (4), an inner lining layer (5), an anti-bite armor layer (6), a high-strength oxygen-barrier binding layer (7), a flame-retardant protective layer (8), and an outer sheath layer (9). The self-healing functional layer includes a matrix material, which is filled with repair agent microcapsules and catalyst microcapsules. The anti-bite armor layer (6) is filled with an irritant-repellent capsule coating.
2. The flame-retardant and bite-resistant power cable for photovoltaic power stations according to claim 1, characterized in that: The matrix material is ethylene-vinyl acetate copolymer, and the addition amount is 90-110 parts by weight; the addition amount of repair agent microcapsules is 10-15 parts by weight, and the addition amount of catalyst microcapsules is 2-5 parts by weight.
3. The flame-retardant and bite-resistant power cable for photovoltaic power stations according to claim 1, characterized in that: The repair agent microcapsules use urea-formaldehyde resin as the wall material and dicyclopentadiene monomer as the core material, with a microcapsule particle size of 5-20 μm; the catalyst microcapsules use urea-formaldehyde resin as the wall material and Grubb catalyst as the core material, with a microcapsule particle size of 5-20 μm.
4. The flame-retardant and bite-resistant power cable for photovoltaic power stations according to claim 1, characterized in that: The insulation layer (2) is a polyolefin insulation material; the buffer water-blocking layer (4) is made of non-woven fabric with super absorbent resin powder adhering to it; the inner lining layer (5) is made of ceramicized silicone rubber composite tape.
5. The flame-retardant and bite-resistant power cable for photovoltaic power stations according to claim 1, characterized in that: The anti-bite armor layer (6) includes a spirally wound aluminum alloy strip (61), the surface of which is provided with an array of diamond-shaped microgrooves (62), and the diamond-shaped microgrooves (62) are filled with an irritant repellent capsule coating (63); the capsules in the irritant repellent capsule coating use β-cyclodextrin as the wall material, and the core material is filled with capsaicin and denatamine, the mass ratio of capsaicin to denatamine is 1:0.3-0.
5.
6. The flame-retardant and bite-resistant power cable for photovoltaic power stations according to claim 1, characterized in that: The high-strength oxygen-barrier binding layer is made of glass fiber reinforced polyester tape.
7. The flame-retardant and bite-resistant power cable for photovoltaic power stations according to claim 1, characterized in that: The flame-retardant protective layer is composed of a flame-retardant coating, which contains the following components in parts by weight: ethylene-vinyl acetate copolymer, 40-60 parts; linear low-density polyethylene, 15-25 parts; ammonium polyphosphate, 20-30 parts; pentaerythritol, 8-15 parts; melamine, 5-10 parts; nano-montmorillonite, 3-8 parts; compatibilizer, 5-10 parts; antioxidant, 1-2 parts.
8. The flame-retardant and bite-resistant power cable for photovoltaic power stations according to claim 1, characterized in that: The outer surface of the flame-retardant protective layer (8) has a set of ring-shaped triangular cross-section support ribs.
9. A flame-retardant and bite-resistant power cable for photovoltaic power stations according to claim 1, characterized in that: The outer sheath is made of halogen-free, low-smoke, flame-retardant polyolefin sheath material, which contains 2%-5% by mass of reversible thermochromic microcapsules.