A moisture-proof cable

Abstract

The present invention relates to the field of power transmission technology, and in particular to a moisture-proof cable comprising, from the inside out, a conductive core, a gradient buffer layer, a dynamic sealing layer, a flexible support layer, and a self-healing sheath. The cable comprises: a conductive core; a gradient buffer layer; a dynamic sealing layer comprising a split sealing structure consisting of an outer annular sealing lip and an inner annular static sealing band; the outer annular sealing lip comprises a polytetrafluoroethylene fiber reinforcement layer embedded in a silicone rubber matrix and coated with a humidity-responsive graphene coating; a flexible support layer comprising a spirally wound nickel-titanium alloy strip with bionic fish scales welded to its surface; and a self-healing sheath comprising an outer molded hexagonal honeycomb structure, containing type A microcapsules containing hydroxyl-terminated polysiloxane and a platinum catalyst, and type B microcapsules containing a modified epoxy resin. The cable exhibits excellent corrosion resistance, moisture resistance, and self-healing capabilities in humid environments, while maintaining good performance even when subjected to external physical impact.

Description

Technical Field

[0001] The present invention relates to the technical field of power transmission, and in particular to a moisture-proof cable. Background Art

[0002] In modern power transmission systems, cables are the core carriers of energy and information, and their reliability is directly related to industrial production and people's livelihood security. However, in complex and changeable humid environments, the protection system of traditional cables faces severe challenges. For example, in cross-sea power supply projects in coastal areas, salt spray erosion and high humidity environments accelerate the hydrolysis and aging of cable insulation, resulting in frequent partial discharge. Fault analysis of a large port power supply system showed that insulation breakdown accidents caused by cable moisture accounted for 42% of the total faults, resulting in losses of more than 10 million yuan per single power outage.

[0003] Existing moisture-proofing technologies often use single-layer water-blocking structures, such as corrugated aluminum sheaths or superabsorbent resin tapes. However, these structures are susceptible to failure under dynamic stress and temperature fluctuations. For example, in a subway tunnel power supply system, microgaps created by thermal expansion and contraction at cable joints resulted in an average annual water seepage rate of 3.2 L / km. However, the mechanical stability of water-blocking powder after expansion in water was insufficient, preventing it from forming a long-term seal. Summary of the Invention

[0004] In order to solve the technical problem that low-voltage cables cannot operate stably for a long time under complex working conditions such as frequent bending, twisting, stretching and pressure in dynamic scenarios, the present invention provides a moisture-proof cable.

[0005] The technical solutions provided by the embodiments of the present invention are as follows:

[0006] A moisture-proof cable comprises, from the inside out, a conductive core, a gradient buffer layer, a dynamic sealing layer, a flexible support layer, and a self-repairing sheath, wherein:

[0007] The conductive core is composed of multiple strands of tinned copper wires, the surface of the copper wires is electroplated with a tin-nickel alloy layer, and the outer surface of the conductive core is covered with a cross-linked polyethylene insulation layer, and the outer surface of the insulation layer is pressed with a spiral groove structure;

[0008] The gradient buffer layer includes, from the inside to the outside, a fluororubber microsphere honeycomb layer, a polyurethane elastomer V-groove layer, and a polytetrafluoroethylene fiber woven mesh layer;

[0009] The dynamic sealing layer consists of a split sealing structure consisting of an outer ring sealing lip and an inner ring static sealing belt. The outer ring sealing lip adopts a silicone rubber matrix with a polytetrafluoroethylene fiber reinforcement layer embedded in it, and the surface is coated with a humidity-responsive graphene coating. The static sealing belt is made of fluororubber.

[0010] The flexible support layer is formed by spirally winding a nickel-titanium alloy strip, and the surface of the nickel-titanium alloy strip is welded with bionic fish scales;

[0011] The self-repairing sheath has a molded hexagonal honeycomb structure on the outer layer, and two-component microcapsules are evenly distributed inside the sheath. In the two-component microcapsules, type A microcapsules contain terminal hydroxyl polysiloxane and platinum catalyst, and type B microcapsules contain modified epoxy resin.

[0012] Preferably, the outer annular sealing lip of the dynamic sealing layer includes a main sealing lip and an auxiliary sealing lip, the root of the main sealing lip is provided with a wavy pleated structure, the auxiliary sealing lip forms an angle of 20°-40° with the main sealing lip, and the surface is provided with a nano-scale hydrophobic texture;

[0013] The humidity-responsive graphene coating is composited with graphene oxide and polydopamine in a weight ratio of 3:1, and has a volume expansion rate of greater than or equal to 15% when the relative humidity is greater than or equal to 85%;

[0014] The static sealing belt is embedded with carbon nanotube bundles, the diameter of the carbon nanotube bundles is 4-6 nm, the length is 50-80 μm, and the volume accounts for 3%-5%.

[0015] Preferably, the bionic fish scales of the flexible support layer have a single scale size of 1.8-2.2 mm×3.8-4.2 mm, and the surface of the scale is coated with an epoxy resin-polyphenylene sulfide composite coating;

[0016] The gaps between adjacent scales are filled with liquid gallium-indium-tin alloy, which has a melting point range of -25°C to -15°C and a surface tension coefficient of 0.4-0.6N / m;

[0017] The surface of the nickel-titanium alloy strip is etched with a stress groove with a depth of 0.04-0.06 mm and a groove width of 0.08-0.12 mm.

[0018] Preferably, the polyurethane elastomer V-groove layer matrix material of the gradient buffer layer is thermoplastic polyurethane with a Shore hardness of 45-55HA, a tensile strength of ≥35MPa, and an elongation at break of ≥500%.

[0019] Silica nanoparticles with a diameter of 50-100 nm are set at the bottom of the groove, with a filling rate of 5%-8%;

[0020] Carbon nanotube bundles are embedded inside the elastomer, with a diameter of 4-6nm, a length of 50-80μm, and a volume share of 3%-5%.

[0021] Preferably, the hexagonal honeycomb structure of the self-repairing sheath is filled with a silicone rubber composite material containing 0.5%-1.5% graphene, and the specific surface area of ​​the graphene is ≥500m 2 / g;

[0022] The microcapsule wall material is polyurethane-urea-formaldehyde resin copolymer with a wall thickness of 2-5μm;

[0023] The outer surface of the sheath is coated with a polytetrafluoroethylene wear-resistant layer.

[0024] Preferably, a semi-conductive shielding layer is provided between the insulating layer of the conductive core and the gradient buffer layer, wherein the material thereof is a composite of ethylene-vinyl acetate copolymer and carbon black, wherein the carbon black content is 25%-35% and the volume resistivity is 10 3 -10 4 Ω·cm;

[0025] The outer surface of the semi-conductive shielding layer is pressed with a diamond grid structure with a depth of 0.05-0.1mm and a grid side length of 2-3mm. The grid is filled with a silicone rubber composite material containing 1%-3% carbon nanotubes.

[0026] Preferably, the carbon black of the semi-conductive shielding layer is conductive carbon black with a particle size of 20-50 nm and a specific surface area of ​​≥800 m 2 / g;

[0027] Silicon dioxide reinforcement particles with a diameter of 0.1-0.2 mm are arranged at the corners of the diamond grid structure, and the surface of the particles is treated with a silane coupling agent.

[0028] Preferably, a stress monitoring layer is provided outside the flexible supporting layer, and the stress monitoring layer includes:

[0029] Polyurethane-based elastomer substrate, Shore hardness of 40-50HA;

[0030] Embed a fiber Bragg grating sensor array in the substrate, with a fiber diameter of 0.15-0.25 mm and a grating spacing of 50-100 mm;

[0031] Distributed strain detection module, sampling frequency ≥ 100 Hz, strain resolution ≤ 1 με.

[0032] Preferably, the optical fiber surface of the fiber Bragg grating sensor array is coated with a polytetrafluoroethylene protective layer;

[0033] 3%-5% of titanium dioxide nanoparticles with a particle size of 20-50nm are added to the polyurethane-based elastomer matrix.

[0034] Preferably, the hexagonal honeycomb structure of the self-repairing sheath is embedded with a micro piezoelectric energy harvester, which includes a lead zirconate titanate piezoelectric ceramic sheet, a flexible electrode layer, and an energy storage unit:

[0035] The lead zirconate titanate piezoelectric ceramic sheet is located at the geometric center of the hexagonal honeycomb structure, with its upper and lower surfaces directly contacting the flexible electrode layer to form a double-sided electrode structure. The lead zirconate titanate piezoelectric ceramic sheet has a size of 1.0-1.5mm×1.0-1.5mm×0.05-0.1mm.

[0036] The flexible electrode layer is composed of a silver nanowire / graphene composite conductive film with a square resistance of ≤10Ω / □;

[0037] The energy storage unit includes solid-state supercapacitors, which are integrated in the form of thin films at the six vertices of the honeycomb unit. Each vertex is equipped with a capacitor, which is connected to the central electrode layer through a conductive path to form a parallel energy storage network with a capacity of 0.5-1.0mF / cm 2 .

[0038] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0039] 1. This invention achieves excellent moisture resistance and mechanical reliability through a multi-layer composite structure. The conductive core is constructed from multiple strands of tin-nickel alloy copper wire. The surface plating layer has been proven to withstand 500 hours of corrosion resistance in a salt spray test. The spiral groove design improves thermal conductivity by 20%. The cross-linked polyethylene (XLPE) insulation layer achieves a breakdown field strength of 30 kV / mm through its cross-linked structure. The spiral grooves are pressed to reduce the dielectric constant to 2.3, suppressing partial discharge.

[0040] 2. The gradient buffer layer of the present invention includes a triple collaborative design: the fluororubber microsphere honeycomb layer absorbs vibration energy through a porosity of 60-70%, the polyurethane V-groove layer is embedded with silica nanoparticles to reduce the wear rate by 50%, and the polytetrafluoroethylene braided mesh prevents interlayer adhesion with a friction coefficient of ≤0.1. The dynamic sealing layer innovatively adopts a main and auxiliary double lip structure. The 0.1-0.2mm wave folds of the main sealing lip and the 20°-40° angle of the auxiliary sealing lip form a pressure gradient. The graphene oxide / polydopamine composite coating produces a 15% volume expansion when the humidity is ≥85% to achieve self-repair. The static sealing tape is embedded with 4-6nm carbon nanotube bundles to form a 10 3 Ω·cm conductive network, with electromagnetic shielding function.

[0041] 3. The flexible support layer of the present invention is spirally wound with nickel-titanium alloy, combined with a bionic fish scale structure, and liquid gallium-indium-tin alloy fills the gap to achieve a gap of ≤1×10 -6 Pa·m 3 / s leakage rate. The self-healing sheath is filled with graphene silicone rubber through a hexagonal honeycomb structure with a compressive strength of ≥50MPa. The two-component microcapsule completes 90% repair within 30 seconds under a critical stress of 1-3MPa. The piezoelectric energy harvesting system uses a combination of lead zirconate titanate ceramic (500pC / N piezoelectric constant) and silver nanowire electrodes to achieve 10μW / cm 3 Energy density. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 A schematic cross-sectional view of a moisture-proof cable provided by an embodiment of the present invention;

[0044] Figure 2 A schematic diagram of a bionic fish scale of a moisture-proof cable provided by an embodiment of the present invention;

[0045] Figure 3 A schematic diagram of a self-repairing sheath of a moisture-proof cable provided by an embodiment of the present invention.

[0046] [reference numerals]

[0047] 1-conductive core, 11-insulating layer, 2-gradient buffer layer, 3-dynamic sealing layer, 31-outer annular sealing lip, 311-main sealing lip, 312-auxiliary sealing lip, 32-inner annular static sealing belt, 4-flexible support layer, 41-bionic fish scale, 5-self-repairing sheath, 51-two-component microcapsule.

[0048] As shown in the figure, in order to clearly implement the structure of the embodiment of the present invention, specific structures and devices are marked in the figure, but this is only for illustrative purposes and is not intended to limit the present invention to the specific structure, device and environment. According to specific needs, ordinary technicians in this field can adjust or modify these devices and environments. DETAILED DESCRIPTION

[0049] The technical solutions of the present invention are described below with reference to the accompanying drawings. It is also noted that, to provide a more detailed description, the following embodiments are best and preferred embodiments, and those skilled in the art may employ alternative implementations for certain known technologies. Furthermore, the accompanying drawings are intended only to provide a more detailed description of the embodiments and are not intended to limit the present invention.

[0050] It should be noted that references in the specification to "one embodiment," "an embodiment," "an exemplary embodiment," "some embodiments," etc. indicate that the described embodiments may include specific features, structures, or characteristics, but not every embodiment necessarily includes such specific features, structures, or characteristics. In addition, when specific features, structures, or characteristics are described in conjunction with an embodiment, it is within the knowledge of persons skilled in the relevant art to implement such features, structures, or characteristics in conjunction with other embodiments (whether or not explicitly described).

[0051] In general, terms can be understood, at least in part, from their use in context. For example, depending at least in part on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending at least in part on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0052] It will be understood that the meanings of “on,” “over,” and “above” in the present invention should be interpreted in the broadest manner, so that “on” means not only “directly on” something but also includes the meaning of being “on” something with intervening features or layers, and “on” or “above” means not only “on” or “above” something but also includes the meaning of being “on” or “above” something with no intervening features or layers.

[0053] Additionally, spatially relative terms such as "below," "beneath," "lower," "above," and "upper" may be used herein for descriptive convenience to describe the relationship of one element or feature to another element or features, as illustrated in the accompanying drawings. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially relative descriptors used herein should be similarly interpreted accordingly.

[0054] like Figures 1 to 3 As shown, embodiments of the present invention provide a moisture-proof cable whose design incorporates multiple advanced materials and technologies to enhance the cable's resistance to moisture and mechanical damage, as well as its self-healing capabilities. The connections and design at each level play a significant role in protecting the cable's performance and extending its service life.

[0055] First, the conductive core is constructed from multiple strands of tinned copper wire, coated with a 5-8μm tin-nickel alloy layer. This design effectively prevents oxidation of the copper wire in humid environments, avoiding increased contact resistance and ensuring excellent electrical conductivity. The twisting pitch is designed to be 10-15 times the conductor diameter, which provides the cable with greater mechanical flexibility and tensile strength. The outer cross-linked polyethylene insulation layer features a spiral groove structure, further optimizing the cable's resistance to external forces, reducing cable failures due to partial discharge, and enhancing electrical safety.

[0056] On this basis, the gradient buffer layer design provides multiple layers of protection through a progressive approach. The innermost layer is a fluororubber microsphere honeycomb layer. The honeycomb pore size and microsphere diameter are designed to effectively absorb external mechanical vibrations, preventing damage to the cable caused by external forces. The outer layer, a polyurethane elastomer V-groove layer and a PTFE fiber braided mesh layer, work together to provide strong wear resistance and tensile strength, ensuring the cable's durability in harsh environments. The PTFE fiber braided mesh further enhances tensile strength and tolerance to external friction.

[0057] The sealing structure, consisting of a dynamic sealing layer and a static sealing strip, effectively prevents moisture penetration in humid environments. The sealing lip is constructed from a silicone rubber matrix embedded with a polytetrafluoroethylene fiber reinforcement layer and coated with a humidity-responsive graphene coating, creating a multi-layer waterproof protection. The humidity-responsive graphene coating expands in response to high humidity, actively filling microcracks and preventing moisture intrusion, significantly improving the cable's moisture resistance.

[0058] The flexible support layer is constructed from a spirally wound nickel-titanium alloy ribbon, with a bionic fish-scale pattern on the surface. The scales overlap by 25%-35%, effectively slowing crack propagation and increasing the cable's tensile strength. The shape memory effect of nickel-titanium alloy ensures the cable returns to its original shape despite environmental changes, enhancing its durability.

[0059] The self-healing sheath utilizes a hexagonal honeycomb structure, which allows for rapid recovery from external damage, preventing further damage. The uniform distribution of the honeycombs and the embedded microcapsules allow the cable to automatically repair itself after damage. In particular, if the microcapsules rupture, the resulting polysiloxane and epoxy resin quickly fill the cracks, preventing moisture penetration and further damage to the cable's insulation.

[0060] By combining materials and structures at various levels, this moisture-proof cable provides comprehensive protection, enhancing its resistance to moisture, corrosion, abrasion, and mechanical shock. It also enhances its long-term reliability through self-healing technology. This design enables the cable to operate stably in extreme environments, extending its service life and reducing maintenance costs, thus possessing significant market value and application prospects.

[0061] In one possible embodiment, by optimizing the structures of the dynamic sealing layer, the humidity-responsive graphene coating, and the static sealing tape, the protection performance of the cable in a humid environment is further enhanced, thereby improving the overall reliability of the cable.

[0062] First, the outer annular sealing lip of the dynamic sealing layer forms a more reliable waterproof sealing structure through the cooperation of the main sealing lip and the auxiliary sealing lip. The lip angle of the main sealing lip is 45°-60°. This design enables the sealing lip to form a closer contact when it comes into contact with external substances, preventing moisture from entering the cable. The wavy pleated structure at the root (pleat depth 0.1-0.2mm) can produce slight deformation when subjected to force, enhancing the sealing effect, and restore its shape after multiple friction or pressure changes, ensuring long-term sealing. The auxiliary sealing lip forms an angle of 20°-40° with the main sealing lip, further increasing the contact pressure of the sealing layer and enhancing the ability to resist external water seepage. In addition, the nano-scale hydrophobic texture set on the surface of the auxiliary sealing lip can effectively reduce the adhesion of water droplets and reduce the penetration of water, ensuring a more reliable sealing effect of the cable in a humid environment.

[0063] The humidity-responsive graphene coating, a composite of graphene oxide and polydopamine, has a thickness of 5-10 μm and automatically responds to humidity changes. When relative humidity reaches 85% or above, the coating expands by 15% or more. This expansion not only enhances the graphene coating's sealing capabilities but also effectively prevents further moisture penetration, improving the cable's stability in high-humidity environments. The composite structure of graphene oxide and polydopamine gives the coating excellent humidity sensing capabilities while also enhancing its mechanical strength and durability, ensuring long-term resistance to failure due to changes in external humidity conditions.

[0064] The carbon nanotube bundles embedded in the static sealing tape enhance its strength and durability through their unique nanostructure. The carbon nanotube bundles have a diameter of 4-6 nm, a length of 50-80 μm, and account for 3%-5% of the tape's volume. The addition of these carbon nanotubes not only enhances the tape's mechanical strength but also improves its sealing properties and electrical conductivity through the nano-effect, making the tape more stable over long-term use and reducing aging and damage caused by temperature and humidity fluctuations.

[0065] This multi-layered design achieves excellent moisture-proof, waterproof, and aging-resistant properties. The dual-seal design of the dynamic sealing layer, the intelligent expansion properties of the humidity-responsive graphene coating, and the reinforcement of carbon nanotubes within the static sealing tape enable the cable to maintain excellent electrical performance and mechanical stability even in extremely humid environments, significantly improving its service life and reliability.

[0066] In one possible implementation, this embodiment optimizes the structure, material selection, and surface treatment of the flexible support layer to improve the mechanical strength, flexibility, and fatigue resistance of the cable, and enhance the reliability of the cable in complex environments.

[0067] First, the flexible support layer adopts a bionic fish scale pattern, with individual scales measuring 1.8-2.2mm x 3.8-4.2mm. This structure not only provides excellent self-locking properties but also evenly distributes stress under external forces, preventing localized damage to the cable. The scales are coated with an epoxy resin-polyphenylene sulfide composite coating with a thickness of 20-30μm, which enhances both wear resistance and chemical corrosion resistance. The epoxy resin and polyphenylene sulfide composite material provides strong physical strength and thermal stability, ensuring that the support layer will not deform, age, or break even after prolonged use.

[0068] Furthermore, the liquid gallium-indium-tin alloy filling the gaps between adjacent scales has a melting point range of -25°C to -15°C and a surface tension coefficient of 0.4-0.6N / m. This alloy filling not only effectively alleviates friction between adjacent scales under external forces, but also, through its low melting point and moderate surface tension, ensures adaptive adjustment when the temperature changes, further enhancing the toughness and impact resistance of the flexible support layer. Furthermore, the design of liquid alloy filling between scales helps avoid mechanical damage caused by local overloads, allowing the cable to maintain elasticity over a wide range and adapt to changing working environments.

[0069] In addition, the stress grooves etched on the surface of the nickel-titanium alloy strip have a depth of 0.04-0.06mm and a groove width of 0.08-0.12mm. The function of the etched grooves is to reduce stress concentration on the surface of the material and slow down the occurrence of metal fatigue. This design can effectively prevent the nickel-titanium alloy from brittle fracture under external forces and enhance the long-term stability of the support layer. Nickel-titanium alloy has a strong shape memory effect and high elasticity, which enables the flexible support layer to return to its original shape after being subjected to force, avoiding permanent deformation of the cable, especially in an environment with large temperature fluctuations, it can still maintain excellent mechanical properties.

[0070] By combining a bionic fish scale structure with high-performance materials such as liquid gallium-indium-tin alloy and nickel-titanium alloy, the flexible support layer of this moisture-proof cable possesses exceptional flexibility, fatigue resistance, and impact resistance. This design effectively enhances the cable's durability and adaptability, enabling it to withstand significant mechanical stress, temperature fluctuations, and long-term wear and tear in complex environments, significantly extending its service life and safety.

[0071] In one possible embodiment, the gradient buffer layer's base material is thermoplastic polyurethane (TPU), with a Shore A hardness of 45-55HA, a tensile strength ≥35 MPa, and an elongation at break ≥500%. This material exhibits excellent elasticity and tensile strength, effectively absorbing and mitigating external impact or tensile stress, preventing the cable from rupturing or deforming under stress. The choice of thermoplastic polyurethane ensures the gradient buffer layer maintains excellent flexibility during long-term use and maintains stable performance under varying temperatures.

[0072] Furthermore, the design of the V-shaped groove layer enables the buffer layer to better disperse external forces. Silica nanoparticles with a diameter of 50-100nm are embedded at the bottom of the groove, with a filling rate of 5%-8%. The addition of silica nanoparticles can increase the hardness and wear resistance of the buffer layer, while improving its bonding with other layers and enhancing the material's resistance to compression and friction. Due to the microscopic size of the nanoparticles, they can improve the mechanical properties of the material at the microscopic level and enhance the overall stability of the buffer layer. In addition, the excellent thermal stability and weather resistance of silica can effectively resist chemical corrosion and high temperature in the external environment, further improving the durability of the cable.

[0073] In addition, the carbon nanotube bundles (4-6nm in diameter, 50-80μm in length, and 3%-5% by volume) embedded within the elastomer further enhance the mechanical properties of the gradient buffer layer. Carbon nanotubes possess very high strength and elastic modulus, significantly improving the buffer layer's resistance to compression, tension, and fatigue, while also increasing its electrical and thermal conductivity. When the cable is subjected to external forces, the carbon nanotube bundles effectively disperse the stress, preventing damage or aging due to frequent bending or stretching during use.

[0074] This design optimizes the performance of the gradient buffer layer by combining a composite material of thermoplastic polyurethane, silica nanoparticles, and carbon nanotube bundles, extending the cable's service life and reliability in various complex environments. The buffer layer effectively absorbs and disperses external forces, resisting environmental influences and maintaining long-term stability for the cable, enabling it to maintain excellent mechanical properties and moisture resistance in a volatile operating environment.

[0075] In one possible embodiment, the design of its self-healing sheath significantly improves the durability, damage resistance and long-term stability of the cable by combining a hexagonal honeycomb structure, graphene reinforcement materials, microcapsule repair technology and a wear-resistant outer coating, especially with extremely high reliability in complex environments.

[0076] First, the hexagonal honeycomb structure as the core structure of the sheath not only provides good mechanical strength and compressive resistance, but also effectively disperses the pressure applied by the outside world. This honeycomb structure design gives the sheath a high structural stability, ensuring that other layers inside the cable are not affected when impacted or bent by external forces, thus avoiding electrical failure of the cable due to external damage. At the same time, the silicone rubber composite material containing 0.5%-1.5% graphene filled in the honeycomb further enhances the flexibility and wear resistance of the sheath. The specific surface area of ​​​​graphene is ≥500m 2 / g, which means it has a larger surface area and stronger thermal conductivity, which can effectively improve the thermal conductivity and electrical properties of the sheath material, while enhancing the mechanical strength of the silicone rubber composite material, so that the sheath remains stable and flexible under high temperature or extreme environments.

[0077] Secondly, the application of microcapsule repair technology gives the cable self-healing capabilities. The microcapsule wall material is made of a polyurethane-urea-formaldehyde resin copolymer, which has a high burst strength (≥5MPa) and temperature resistance. When subjected to external mechanical damage, the microcapsules rupture and release repair material, automatically filling minor cracks or damage on the sheath surface. This repair function can extend the cable's service life and prevent serious damage caused by the expansion of small cracks. This self-healing mechanism allows the cable to quickly recover its structure in the face of external damage, reducing maintenance costs and enhancing the cable's long-term stability.

[0078] Finally, the outer surface of the sheath is coated with a 10-20μm thick polytetrafluoroethylene (PTFE) wear-resistant layer with a surface friction coefficient of ≤0.15. PTFE has an extremely low friction coefficient and excellent wear resistance, effectively reducing wear and tear on the cable surface from contact with external objects, preventing damage caused by friction while also improving the cable's resistance to contamination. Furthermore, the PTFE wear-resistant layer exhibits excellent chemical stability, protecting against acid and alkali corrosion and oil contamination, ensuring the cable's long-term use in humid and harsh environments.

[0079] Combining a hexagonal honeycomb structure, graphene-enhanced silicone rubber composites, microcapsule self-healing technology, and a polytetrafluoroethylene wear-resistant layer, this moisture-proof cable offers significant advantages, particularly in terms of improved damage resistance, repairability, and abrasion resistance. These features enable the cable to maintain excellent performance and stability despite long-term use, external friction, temperature fluctuations, chemical corrosion, and physical damage, significantly extending its service life and reliability.

[0080] In one possible implementation, the addition of a semiconductive shielding layer enhances the cable's electromagnetic shielding performance and further improves its stability and anti-interference capabilities in complex environments. Specifically, the semiconductive shielding layer is composed of a composite material of ethylene-vinyl acetate copolymer and carbon black. Its diamond-shaped grid structure and embedded carbon nanotubes effectively suppress electromagnetic interference, enhancing the cable's overall performance.

[0081] First, the selection of ethylene-vinyl acetate copolymer and carbon black composite material makes the semi-conductive shielding layer have appropriate conductive properties. The carbon black content is 25%-35%, and its volume resistivity is 10 3 -10 4 A resistivity within this range of 100 Ω·cm ensures the shielding layer has good conductivity, effectively absorbing and shielding external electromagnetic waves, while not affecting the current signal within the cable, thereby achieving electromagnetic interference (EMI) shielding. By properly controlling the proportion of carbon black, the cable's electrical performance can be optimized, ensuring stable signal transmission and interference resistance.

[0082] In addition, the outer surface of the semi-conductive shield is pressed with a diamond-shaped grid structure (grid side length 2-3mm, pressed depth 0.05-0.1mm), further enhancing the shield's mechanical strength and improving its surface heat dissipation. This grid structure effectively increases the shield's surface area, improving its contact area with the external environment and thus enhancing its electromagnetic shielding effectiveness. This structural design also effectively disperses external impact forces, reducing damage to the cable and protecting the internal structure from physical damage.

[0083] Finally, the mesh is filled with a silicone rubber composite containing 1%-3% carbon nanotubes, further enhancing electromagnetic shielding while also improving the material's flexibility and fatigue resistance. The incorporation of carbon nanotubes increases the composite's mechanical strength and electrical conductivity, making the shield not only more electrically efficient but also more resistant to abrasion and weathering. The inherent flexibility of silicone rubber imparts a degree of elasticity to the shield, allowing it to adapt to the bending and stretching of the cable during installation and use, preventing cracks or damage caused by external stresses.

[0084] The semi-conductive shielding layer, through rational material selection and structural design, offers multiple benefits in moisture-resistant cables. It not only effectively shields electromagnetic interference and improves signal transmission quality, but also enhances the cable's mechanical strength and resistance to external damage, ensuring stability and durability over long-term use. This design enables the cable to maintain excellent performance in high-interference, high-temperature, or harsh environments, ensuring long-term reliable operation of equipment.

[0085] In one possible implementation, the design of its semiconductive shield further optimizes the cable's electrical performance and mechanical strength. By using a specific type of conductive carbon black and adding silica reinforcement particles at the corners of the mesh structure, the cable's electromagnetic shielding effectiveness, mechanical durability, and resistance to external impact are significantly improved.

[0086] First, the selection of conductive carbon black is crucial to improving the electrical performance of the semi-conductive shielding layer. 2 / g of conductive carbon black significantly improves its conductivity and shielding properties. Due to its small particle size and large specific surface area, the conductive carbon black forms a more uniform conductive network within the semi-conductive shielding layer, enhancing its conductivity and providing the cable with improved electromagnetic interference (EMI) shielding. This carbon black effectively blocks external electromagnetic waves while maintaining stable signal transmission within the cable, protecting the signal from external electromagnetic interference. This advantage is particularly evident during high-frequency signal transmission.

[0087] Secondly, the design of silica reinforcing particles at the corners of the diamond-shaped grid structure further enhances the mechanical strength and wear resistance of the shielding layer. The corners are the parts of the grid structure that are most susceptible to stress concentration and external damage. Therefore, by adding silica reinforcing particles with a diameter of 0.1-0.2mm at the corners, external forces can be effectively dispersed to avoid rupture or damage caused by excessive local stress. In addition, the surface of the silica particles is treated with a silane coupling agent to form a stronger interfacial bonding force between the particles and the surrounding composite material, thereby improving the bonding strength and durability of the reinforcing particles to the shielding layer matrix. This surface treatment can improve the dispersion of the particles and make them evenly distributed in the composite material, thereby optimizing the mechanical properties and aging resistance of the cable.

[0088] Through this design, the moisture-proof cable not only performs better in electrical shielding effect, but also can better resist external mechanical impact, friction and chemical corrosion during actual use, ensuring that the cable can maintain long-term stable operation in high temperature, high humidity or other extreme environments.

[0089] This design enhances the electromagnetic shielding effectiveness of the semi-conductive shielding layer by optimizing the selection and particle size control of the conductive carbon black. Furthermore, by adding silica reinforcement particles to the corners of the mesh structure and treating it with a silane coupling agent, the cable's mechanical strength and damage resistance are enhanced. These innovative measures not only improve the cable's overall performance but also significantly extend its service life and stability, particularly in high-interference environments and extreme physical conditions.

[0090] In one possible implementation, a stress monitoring layer is added to the outside of the flexible support layer, providing significant intelligent monitoring capabilities. By integrating a fiber Bragg grating sensor array with a distributed strain detection module, this design enables real-time monitoring of stress changes during cable operation, providing dynamic monitoring of the cable's operating status and improving its reliability and safety in harsh environments.

[0091] First, the choice of a polyurethane-based elastomer substrate ensures excellent elasticity and durability in the stress monitoring layer. Polyurethane-based elastomers offer excellent resistance to wear, weathering, and aging. Their Shore A hardness range of 40-50 HA ensures flexibility while effectively absorbing and dissipating external mechanical stress. This substrate not only protects the fiber Bragg grating sensor from external physical damage but also provides sufficient mechanical support to ensure its proper operation.

[0092] Secondly, an array of fiber grating (FBG) sensors embedded in the substrate is the core component of the stress monitoring layer. FBG sensors measure strain with high precision by sensing wavelength changes caused by tiny deformations in the optical fiber. These optical fibers have a diameter of 0.15-0.25mm, adapting to cable bending and deformation, ensuring the sensor remains stable even when the cable is subjected to external forces. The grating spacing is 50-100mm, enabling strain monitoring over long distances and providing sufficient spatial resolution to detect localized strain changes within the cable.

[0093] Finally, the addition of a distributed strain detection module makes the entire monitoring system even more intelligent. This module boasts high-precision detection capabilities with a sampling frequency of ≥100Hz and a strain resolution of ≤1με. It monitors cable strain in real time, particularly under high loads, frequent bending, or stretching, and promptly detects any abnormal strain changes. This real-time monitoring of cable stress provides early warnings of potential cable damage or excessive strain, preventing potential safety hazards in advance. This reduces the risk of cable failure and extends the cable's service life.

[0094] The stress monitoring layer integrates fiber grating sensors and strain detection modules within the cable. This not only provides real-time monitoring of cable strain during use, but also provides early warning to prevent damage from excessive stress. This design enhances cable safety and reliability and is particularly suitable for cables exposed to long-term operation and complex environments, such as submarine cables and long-distance power transmission lines. This intelligent monitoring technology makes cable fault detection and maintenance more efficient, effectively reducing maintenance costs and improving equipment operational efficiency.

[0095] In one possible implementation, the fiber Bragg grating sensor's protection, substrate performance, and temperature compensation accuracy are further optimized. These innovative designs significantly enhance the cable's overall performance, particularly in terms of high-precision stress monitoring and environmental adaptability.

[0096] First, the optical fibers of the FBG sensor array are coated with a protective layer of polytetrafluoroethylene (PTFE) (0.5-1.0 μm thick). This design enhances the durability and environmental resistance of the FBG sensor. PTFE is a highly corrosion-resistant and heat-resistant material with excellent insulating properties. When applied to the optical fiber, it effectively protects it from moisture, chemicals, oxides, and other corrosive substances. This protective layer not only extends the life of the fiber but also ensures the stable operation of the FBG in harsh environments, enabling the cable to provide accurate strain data even under more complex operating conditions.

[0097] Secondly, 2%-5% titanium dioxide nanoparticles with a particle size of 20-50 nm are added to the polyurethane-based elastomer matrix. This improvement is intended to enhance the mechanical properties and thermal stability of the matrix. The titanium dioxide nanoparticles act as a reinforcement within the polyurethane matrix, not only increasing the matrix's strength, hardness, and abrasion resistance, but also effectively improving the cable's UV and aging resistance. When the cable is subjected to external mechanical stress or environmental changes, the addition of titanium dioxide nanoparticles provides better support and protection, ensuring that the fiber Bragg grating sensor remains unaffected during monitoring, maintaining high reliability.

[0098] Finally, the temperature compensation unit utilizes a platinum resistance temperature sensor, achieving a temperature measurement accuracy of ±0.1°C. Temperature fluctuations can interfere with the fiber Bragg grating sensor's measurements. Therefore, the addition of the temperature compensation unit effectively eliminates the effects of temperature on strain data, ensuring that temperature fluctuations do not distort the monitored data. The platinum resistance temperature sensor, with its high precision and stability, monitors the ambient temperature around the cable in real time and, by combining it with the fiber Bragg grating sensor's data, provides compensation, thereby improving the accuracy and consistency of strain measurements.

[0099] The research team embedded a fiber Bragg grating (FBG) sensor array into a polyurethane-based elastomer matrix. The fiber surface was coated with a polytetrafluoroethylene (PTFE) layer to enhance durability. Titanium dioxide nanoparticles were added to the matrix to enhance its mechanical properties and thermal stability. A temperature compensation unit worked in conjunction with the FBG sensor to improve the accuracy of strain data.

[0100] This design not only enhances mechanical and environmental adaptability, but also accurately monitors strain changes and effectively avoids errors caused by temperature fluctuations. This allows the cable to provide more reliable monitoring data in complex environments, making it suitable for demanding applications such as marine cables and telecommunications, where precision is paramount.

[0101] In one possible implementation, micro-piezoelectric energy harvesters are embedded within the hexagonal honeycomb structure of the self-healing sheath, enabling the cable to self-collect and store energy, thereby enhancing its energy independence and extending its service life. This design provides a continuous power supply solution for the cable, particularly suitable for applications where external power is difficult to access, such as remote monitoring systems, drones, and other automated equipment.

[0102] Lead zirconate titanate piezoelectric ceramic sheets, as the core components of the piezoelectric energy harvester, have dimensions of 1.0-1.5mm×1.0-1.5mm×0.05-0.1mm. This piezoelectric ceramic sheet has excellent piezoelectric properties and can convert mechanical energy into electrical energy when subjected to external forces (such as cable bending, vibration or pressure). Its tiny size allows the piezoelectric ceramic sheet to be easily embedded in the honeycomb structure of the cable, which does not increase the volume of the cable while effectively collecting mechanical energy from the external environment. In this way, the cable can convert environmental energy into electrical power in real time when subjected to vibration or external forces, supporting the normal operation of other electronic components in the cable.

[0103] The flexible electrode layer is composed of a silver nanowire / graphene composite conductive film with a square resistance of ≤10Ω / □, demonstrating excellent conductivity and flexibility. The silver nanowire and graphene composite material effectively reduces the electrode's resistance, improving current transmission efficiency and ensuring that the electrode layer does not deform and fail when the cable is bent or subjected to stress. Furthermore, the flexible electrode layer tightly bonds with the piezoelectric ceramic, bridging the gap between the voltage output generated by the piezoelectric effect and the current collection, ensuring efficient energy conversion and transmission.

[0104] The energy storage unit uses a solid-state supercapacitor with a capacity of 0.5-1.0mF / cm 2 Supercapacitors can quickly store the electrical energy collected from the piezoelectric ceramic and release it when needed. This design allows the cable to store energy in the capacitor when the collected energy is insufficient to directly drive the load, and then supply it to the system when sufficient energy is available, ensuring that the cable can maintain a long-term energy supply.

[0105] The piezoelectric ceramic converts external mechanical energy into electrical energy, which is then transmitted to the energy storage unit (solid-state supercapacitor) via the silver nanowire / graphene composite conductive film, allowing the cable to be self-powered. By embedding the piezoelectric energy harvester in the hexagonal honeycomb structure, not only can the cable's energy self-sufficiency be improved, but the overall structural strength and durability of the cable can also be improved. The hexagonal honeycomb structure design provides additional mechanical support, allowing the energy harvester to continue to operate stably when the cable is under stress, without failing due to the external environment or cable deformation.

[0106] This design can improve the functionality and reliability of the cable and is particularly suitable for complex environments that require long-term, maintenance-free operation, such as smart cities and automated monitoring systems.

[0107] The present invention encompasses any alternatives, modifications, equivalents, and solutions that fall within the spirit and scope of the present invention. While specific details are described in detail in the preferred embodiments to provide a thorough understanding of the present invention, those skilled in the art will be able to fully understand the present invention without these details. Furthermore, to avoid unnecessary confusion regarding the essence of the present invention, well-known methods, processes, procedures, components, and circuits have not been described in detail.

[0108] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A moisture-proof cable, characterized in that: From the inside out, it includes a conductive core, a gradient buffer layer, a dynamic sealing layer, a flexible support layer, and a self-repairing sheath, wherein: The conductive core is composed of multiple strands of tinned copper wires, the surface of the copper wires is electroplated with a tin-nickel alloy layer, and the outer surface of the conductive core is covered with a cross-linked polyethylene insulation layer, and the outer surface of the insulation layer is pressed with a spiral groove structure; The gradient buffer layer includes, from the inside to the outside, a fluororubber microsphere honeycomb layer, a polyurethane elastomer V-groove layer, and a polytetrafluoroethylene fiber woven mesh layer; The dynamic sealing layer consists of a split sealing structure consisting of an outer ring sealing lip and an inner ring static sealing belt. The outer ring sealing lip adopts a silicone rubber matrix with a polytetrafluoroethylene fiber reinforcement layer embedded in it, and the surface is coated with a humidity-responsive graphene coating. The static sealing belt is made of fluororubber. The flexible support layer is formed by spirally winding a nickel-titanium alloy strip, and the surface of the nickel-titanium alloy strip is welded with bionic fish scales; The self-repairing sheath has a molded hexagonal honeycomb structure on the outside and two-component microcapsules are evenly distributed inside the sheath. Type A microcapsules contain hydroxyl-terminated polysiloxane and platinum catalyst, while type B microcapsules contain modified epoxy resin. The outer annular sealing lip of the dynamic sealing layer includes a main sealing lip and an auxiliary sealing lip. The root of the main sealing lip is provided with a wavy pleated structure. The auxiliary sealing lip forms an angle of 20°-40° with the main sealing lip, and the surface is provided with a nano-scale hydrophobic texture. The humidity-responsive graphene coating is composed of graphene oxide and polydopamine in a weight ratio of 3:1, and when the relative humidity is greater than or equal to 85%, the volume expansion rate is greater than or equal to 15%; The static sealing tape is embedded with carbon nanotube bundles, the diameter of the carbon nanotube bundles is 4-6 nm, the length is 50-80 μm, and the volume accounts for 3%-5%; In the bionic fish scales of the flexible support layer, the size of a single scale is 1.8-2.2 mm×3.8-4.2 mm, and the surface of the scale is coated with an epoxy resin-polyphenylene sulfide composite coating; The gaps between adjacent scales are filled with liquid gallium-indium-tin alloy, which has a melting point range of -25°C to -15°C and a surface tension coefficient of 0.4-0.6N / m; The surface of the nickel-titanium alloy strip is etched with a stress groove with a depth of 0.04-0.06 mm and a groove width of 0.08-0.12 mm.

2. A moisture-proof cable according to claim 1, characterized in that: The polyurethane elastomer V-groove layer matrix material of the gradient buffer layer is thermoplastic polyurethane with a Shore hardness of 45-55HA, a tensile strength of ≥35MPa, and an elongation at break of ≥500%; Silica nanoparticles with a diameter of 50-100 nm are set at the bottom of the groove, with a filling rate of 5%-8%; Carbon nanotube bundles are embedded inside the elastomer, with a diameter of 4-6nm, a length of 50-80μm, and a volume share of 3%-5%.

3. A moisture-proof cable according to claim 2, characterized in that: The hexagonal honeycomb structure of the self-repairing sheath is filled with a silicone rubber composite material containing 0.5%-1.5% graphene, and the specific surface area of ​​the graphene is ≥500m² / g; The microcapsule wall material is polyurethane-urea-formaldehyde resin copolymer with a wall thickness of 2-5μm; The outer surface of the sheath is coated with a polytetrafluoroethylene wear-resistant layer.

4. A moisture-proof cable according to any one of claims 1 to 3, characterized in that: A semi-conductive shielding layer is provided between the insulating layer of the conductive core and the gradient buffer layer. The material of the semi-conductive shielding layer is a composite of ethylene-vinyl acetate copolymer and carbon black, with a carbon black content of 25%-35% and a volume resistivity of 10³-10 4 Ω·cm; The outer surface of the semi-conductive shielding layer is pressed with a diamond grid structure with a depth of 0.05-0.1 mm and a grid side length of 2-3 mm. The grid is filled with a silicone rubber composite material containing 1%-3% carbon nanotubes.

5. A moisture-proof cable according to claim 4, characterized in that: The carbon black of the semi-conductive shielding layer is conductive carbon black with a particle size of 20-50 nm and a specific surface area of ​​≥800 m² / g; Silicon dioxide reinforcement particles with a diameter of 0.1-0.2 mm are arranged at the corners of the diamond grid structure, and the surface of the particles is treated with a silane coupling agent.

6. A moisture-proof cable according to any one of claims 5, characterized in that: A stress monitoring layer is provided outside the flexible supporting layer, and the stress monitoring layer includes: Polyurethane-based elastomer substrate, Shore hardness of 40-50HA; Embed a fiber Bragg grating sensor array in the substrate, with a fiber diameter of 0.15-0.25 mm and a grating spacing of 50-100 mm; Distributed strain detection module, sampling frequency ≥ 100 Hz, strain resolution ≤ 1 με.

7. The moisture-proof cable according to claim 6, characterized in that: The optical fiber surface of the fiber grating sensor array is coated with a polytetrafluoroethylene protective layer; 3%-5% titanium dioxide nanoparticles with a particle size of 20-50nm are added to the polyurethane-based elastomer matrix.

8. The moisture-proof cable according to claim 7, characterized in that: The hexagonal honeycomb structure of the self-repairing sheath is embedded with a micro piezoelectric energy harvester, which includes a lead zirconate titanate piezoelectric ceramic sheet, a flexible electrode layer, and an energy storage unit. The lead zirconate titanate piezoelectric ceramic sheet is located at the geometric center of the hexagonal honeycomb structure, with its upper and lower surfaces directly contacting the flexible electrode layer to form a double-sided electrode structure. The lead zirconate titanate piezoelectric ceramic sheet has a size of 1.0-1.5mm×1.0-1.5mm×0.05-0.1mm. The flexible electrode layer is composed of a silver nanowire / graphene composite conductive film with a square resistance of ≤10Ω / □; The energy storage unit includes a solid-state supercapacitor, which is integrated in the form of a thin film at the six vertices of the honeycomb unit. Each vertex is equipped with a capacitor, which is connected to the central electrode layer through a conductive path to form a parallel energy storage network with a capacity of 0.5-1.0mF / cm².

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