An adaptive temperature control type electric wire cable based on a phase change material and a manufacturing method thereof

Abstract

The application relates to a self-adaptive temperature control type electric wire cable based on a phase change material and a manufacturing method thereof, and belongs to the technical field of electric wire cables. A technical scheme: phase change temperature control insulation layers, phase change temperature control buffer layers and outer sheaths are dispersed with phase change material microcapsules and heat conduction reinforcing fillers; the phase change material microcapsules comprise wall materials and core materials, the core materials are phase change materials, and the wall materials are high polymer materials; when the cable temperature rises, the phase change material absorbs heat and changes phase, and stores heat energy in the form of latent heat; when the cable temperature decreases, the phase change material releases heat and changes in a reverse phase, and releases the stored heat energy. The application can automatically adjust the temperature during operation, absorbs and stores excessive heat when the temperature is high, releases the stored heat when the temperature is low, realizes active control of the cable temperature and efficient utilization of heat energy, can buffer temperature fluctuation, reduces the influence of temperature change on the cable performance, and improves the adaptability and operation reliability of the cable in an extreme temperature environment.

Description

TECHNICAL FIELD

[0001] The present application relates to a self-adaptive temperature control type electric wire cable based on phase change material and its manufacturing method, in particular, a self-adaptive temperature control cable capable of automatically adjusting temperature, storing and reusing heat energy during operation, belonging to the technical field of electric wire cable. BACKGROUND

[0002] As an important carrier for power transmission and signal transmission, electric wire cable plays an indispensable role in modern industry, construction, transportation and daily life. With the continuous progress of science and technology and the continuous expansion of application fields, the performance requirements of electric wire cable are increasingly improved, especially in terms of thermal management, temperature stability and operation reliability. The traditional electric wire cable structure is usually composed of conductor, insulation layer, shielding layer and sheath, etc. This structure design can meet the basic electrical performance requirements under normal use conditions, but in actual application process, the cable often faces various complex thermal environments and temperature change challenges. In the aspect of cable heat dissipation and temperature control technology, the existing technology mainly includes porous heat dissipation type cable structure, which sets up pipe material for heat dissipation at the center of the cable, and extrudes and packs fan-shaped heat dissipation rubber body outside the cable unit, and sets up heat dissipation holes in the rubber body, so as to facilitate the dissipation of heat generated by the cable during use, preventing the cable from overheating and damage. In addition, there are cables using inorganic nano flame-retardant composite polyolefin as outer sheath layer material, and cables using low smoke and halogen-free flame-retardant material structure. However, these technical solutions mainly focus on passive heat dissipation and flame-retardant performance of the cable, lacking active temperature control and heat energy storage capacity.

[0003] The electric wire cable in the prior art has the following main shortcomings: Firstly, it lacks active temperature control capability. When the cable generates heat during operation, the traditional cable can only dissipate heat to the surrounding environment through passive methods such as heat conduction, heat convection and heat radiation. This passive heat dissipation method has limited effect in high ambient temperature or poor heat dissipation conditions, which can easily lead to high cable temperature, accelerate the aging of insulation materials, reduce the service life of the cable, and even cause safety accidents. The existing technology cannot actively adjust and control the temperature of the cable, and cannot maintain the stability of the cable temperature under different environmental conditions; Secondly, the electric wire cable in the prior art cannot store and reuse heat energy. The heat generated by the cable during operation is usually considered as useless energy and directly dissipated to the environment, which not only causes energy waste, but also requires additional heating equipment in heating occasions (such as cable start-up in cold environments), increasing the complexity and energy consumption of the system. The existing technology lacks effective heat energy storage and release mechanism, cannot realize the time and space transfer and reuse of heat energy, and cannot meet the requirements of energy saving and green development; Furthermore, the performance of existing wires and cables is unstable in environments with large temperature fluctuations. The electrical properties (such as resistance, insulation resistance, and dielectric constant) and mechanical properties (such as tensile strength and bending performance) of cables are all affected by temperature. When the ambient or operating temperature fluctuates drastically, the cable's performance also fluctuates, affecting the stability and reliability of power transmission. Current technologies lack effective temperature buffering mechanisms, failing to reduce the impact of temperature fluctuations on cable performance and making it difficult to meet the requirements of high-precision power and signal transmission. Finally, existing wires and cables have poor adaptability to extreme temperature environments. At high temperatures, the cable insulation material is prone to softening and aging, leading to a decline in insulation performance; at low temperatures, the insulation material is prone to becoming brittle and cracking, resulting in a decrease in mechanical properties. Furthermore, existing technologies lack effective temperature regulation mechanisms, making it impossible to protect cables in extreme temperature environments and limiting their application in special situations (such as polar regions, deserts, and high-temperature industrial environments).

[0004] Therefore, there is an urgent need to develop a type of wire and cable with active temperature control capabilities, the ability to store and reuse thermal energy, the ability to buffer temperature fluctuations, and the ability to adapt to extreme temperature environments, in order to improve the temperature stability, operational reliability, and service life of the cable. Summary of the Invention

[0005] This invention proposes an adaptive temperature-controlled wire and cable based on phase change material and its manufacturing method. It can automatically adjust the temperature during operation, absorb and store excess heat at high temperatures, and release the stored heat at low temperatures, thereby achieving active temperature control and efficient utilization of thermal energy. At the same time, it can buffer temperature fluctuations, reduce the impact of temperature changes on cable performance, improve the adaptability and operational reliability of the cable in extreme temperature environments, and solve the above-mentioned technical problems existing in the prior art.

[0006] The technical solution of this invention is: An adaptive temperature-controlled wire and cable based on phase change material (PCM) comprises, from the inside out, a conductor, a PCM temperature-controlled insulation layer, a shielding layer, a PCM temperature-controlled buffer layer, and an outer sheath. PCM microcapsules and thermally conductive reinforcing fillers are dispersed within the PCM insulation layer, the PCM temperature-controlled buffer layer, and the outer sheath. Each PCM microcapsule comprises a wall material and a core material, wherein the core material is a PCM material and the wall material is a polymer material. When the cable temperature rises, the PCM material absorbs heat and undergoes a phase change, storing the heat energy as latent heat. When the cable temperature decreases, the PCM material releases heat and undergoes a reverse phase change, releasing the stored heat energy.

[0007] The core material of the phase change material microcapsule comprises one or more of n-alkanes, paraffin wax, fatty acids, and polyethylene glycol, and the wall material comprises one or more of melamine resin, polyurethane, and urea-formaldehyde resin.

[0008] The conductor is made of copper or aluminum, and the shielding layer is made of copper strip, aluminum strip, or woven copper mesh.

[0009] A method for manufacturing an adaptive temperature-controlled wire and cable based on phase change material (PCM) comprises, from the inside out, a conductor, a PCM temperature-controlled insulation layer, a shielding layer, a PCM temperature-controlled buffer layer, and an outer sheath. PCM microcapsules and thermally conductive reinforcing fillers are dispersed in the PCM insulation layer, the PCM temperature-controlled buffer layer, and the outer sheath. Each PCM microcapsule comprises a wall material and a core material, wherein the core material is a PCM and the wall material is a polymer material. The PCM microcapsules have a particle size of 10-100 micrometers, and their mass fraction in the PCM insulation layer is 5%-20%, in the PCM buffer layer is 5%-25%, and in the outer sheath is 0%-15%. The thermally conductive reinforcing filler has a mass fraction of 1%-10% in the PCM insulation layer and 1%-8% in the PCM buffer layer.

[0010] The thermally conductive reinforcing filler comprises one or more of expanded graphite, graphene, carbon nanotubes, carbon fibers, and metal powder.

[0011] The phase change temperature control insulation layer uses cross-linked polyethylene, ethylene propylene rubber or silicone rubber as the base material, the phase change temperature control buffer layer uses silicone rubber, thermoplastic elastomer or polyurethane as the base material, and the outer sheath uses polyvinyl chloride, polyethylene or thermoplastic polyurethane as the base material.

[0012] The phase change temperature control insulating layer and the phase change temperature control buffer layer contain microcapsules of various phase change materials with different phase change temperatures, forming a multi-level phase change temperature control structure. The phase change temperature range of the phase change material microcapsules with different phase change temperatures is 20℃-80℃.

[0013] The phase change material microcapsules are prepared by in-situ polymerization, interfacial polymerization or complex condensation.

[0014] The thickness of the phase change temperature control insulation layer is 1.5-5.0 mm, the thickness of the phase change temperature control buffer layer is 0.5-3.0 mm, and the thickness of the outer sheath is 1.0-4.0 mm.

[0015] The cable has an operating temperature range of -40℃ to 125℃.

[0016] A method for manufacturing an adaptive temperature-controlled wire and cable based on phase change materials includes at least two methods; The first specific step: ① Preparation of phase change material microcapsules; Microcapsules coated with n-octadecane by melamine resin were prepared by in-situ polymerization. Melamine resin prepolymer was mixed with n-octadecane and water-in-oil emulsion was formed under high-speed shear emulsification. The pH and temperature were adjusted to polymerize melamine resin on the surface of n-octadecane droplets to form a dense capsule wall. After filtration, washing and drying, phase change microcapsules with a particle size of 10-100 micrometers were obtained. ②Prepare phase change temperature control insulation layer and phase change temperature control buffer layer materials; mix phase change material microcapsules, thermally conductive reinforcing fillers and matrix materials (XLPE or silicone rubber) evenly in an internal mixer, and control the mixing temperature to be lower than the phase change temperature of the phase change material to avoid premature phase change of the phase change material; ③ Cable manufacturing: The three-layer co-extrusion technology is used to simultaneously extrude the conductor, phase change temperature-controlled insulation layer and shielding layer, then wrap or extrude the phase change temperature-controlled buffer layer, and finally extrude the outer sheath. The extrusion temperature and cooling rate are controlled to ensure that the phase change material microcapsules will not rupture or leak during the extrusion process.

[0017] Working Principle: During cable operation, the conductor generates heat due to the current flowing through it, which is transferred to the phase change temperature-controlled insulation layer via thermal conduction. When the temperature of the phase change insulation layer rises above the phase change temperature of the phase change material, the phase change material begins to absorb heat and undergoes a solid-liquid phase change, storing the heat energy as latent heat and inhibiting further temperature increases. When the cable load decreases or the ambient temperature drops, the temperature of the phase change insulation layer falls below the phase change temperature of the phase change material. The phase change material then releases the stored heat and undergoes a liquid-solid phase change, providing heating for the phase change insulation layer and preventing it from becoming too cold. Through this phase change energy storage and heat release mechanism, active regulation and buffering of cable temperature are achieved, reducing the impact of temperature fluctuations on cable performance and improving the cable's operational reliability and service life.

[0018] The second specific step: ①Preparation of phase change material microcapsules with multiple phase change temperatures; Phase change material microcapsules with different phase change temperatures were prepared by in-situ polymerization. By selecting n-alkanes with different carbon chain lengths (such as n-eicosane, n-tetracosane, and n-octacosane) as core materials, microcapsules with different phase change temperatures were obtained. ②Preparation of phase change temperature-controlled insulation layer and phase change temperature-controlled buffer layer materials; mixing microcapsules of phase change materials with different phase change temperatures, and mixing them evenly with thermally conductive reinforcing fillers and matrix materials (XLPE or TPE) in an internal mixer, controlling the mixing temperature to be lower than the minimum phase change temperature (20℃) to avoid premature phase change of the phase change materials; ③ Cable manufacturing: The three-layer co-extrusion technology is used to simultaneously extrude the conductor, phase change temperature-controlled insulation layer and shielding layer, then the phase change temperature-controlled buffer layer is extruded, and finally the outer sheath is extruded, controlling the extrusion temperature and cooling rate.

[0019] Working Principle: During cable operation, the heat generated by the conductor is transferred to the phase change temperature-controlled insulation layer through heat conduction. When the temperature of the phase change temperature-controlled insulation layer rises, phase change materials with different phase change temperatures undergo phase changes successively, absorbing and storing heat to suppress further temperature increases. When the temperature of the phase change temperature-controlled insulation layer decreases, phase change materials with different phase change temperatures release the stored heat, providing heating for the insulation layer and preventing it from becoming too cold. Through this multi-stage phase change energy storage and heat release mechanism, a wide range of cable temperature regulation and buffering is achieved, significantly improving the cable's adaptability and operational reliability in environments with large temperature variations.

[0020] Technical Advantages: The multi-stage phase change temperature design expands the cable's temperature control range and capability. When the cable temperature is low (e.g., 20-30℃), the low-temperature phase change microcapsules undergo phase change first, absorbing or releasing heat. As the cable temperature continues to rise or fall, the medium- and high-temperature phase change microcapsules undergo phase change successively, forming a continuous temperature control range, enabling wide-range temperature regulation and buffering of the cable. This multi-stage phase change temperature design significantly improves the cable's temperature control capability and temperature adaptability, making it suitable for applications with large temperature variations. Furthermore, by adding high thermal conductivity fillers such as graphene nanosheets and carbon nanotubes, a highly efficient thermally conductive network can be constructed within the cable material, improving the heat transfer efficiency of the phase change material, shortening its response time, and enabling it to respond to temperature changes more quickly, thus improving the dynamic performance of the temperature control system.

[0021] The key technical point of this invention is: Selection and design of phase change materials: Suitable phase change materials need to be selected based on the cable's operating temperature range, temperature control requirements, and application environment. This includes optimizing parameters such as phase change temperature, latent heat of phase change, thermal conductivity, and cycle stability. n-Alkane-based phase change materials, with their suitable phase change temperature, high latent heat of phase change, good chemical stability, and cycle stability, are the preferred materials for this invention.

[0022] Preparation and encapsulation of phase change material microcapsules: Suitable encapsulation materials and processes are required to encapsulate liquid or solid phase change materials within tiny capsules, preventing leakage during melting while maintaining the phase change properties and cycle stability of the material. In-situ polymerization is a commonly used microcapsule preparation method, capable of producing phase change microcapsules with uniform particle size, dense walls, and high encapsulation efficiency.

[0023] Dispersion and composite of phase change material microcapsules in cable materials: It is necessary to ensure that the phase change material microcapsules are uniformly dispersed in the matrix material to avoid agglomeration. Simultaneously, it is necessary to optimize the addition ratio of phase change material microcapsules to balance temperature control performance, insulation performance, mechanical properties, and processing performance. Uniform dispersion of phase change material microcapsules can be achieved by optimizing the mixing process and adding dispersants.

[0024] Construction of thermally conductive enhanced networks: By adding high thermal conductivity fillers (such as graphene, carbon nanotubes, carbon fibers, metal powders, etc.), a continuous thermally conductive network is constructed in the cable material to improve the heat transfer efficiency of the phase change material and shorten its response time. The type, amount, and dispersion method of the thermally conductive filler have a significant impact on the formation of the thermally conductive network.

[0025] Optimized cable structure design requires careful consideration of the thickness of each material layer, the distribution of phase change material microcapsules, and the layout of the heat-conducting network to achieve an optimal balance between temperature control performance, electrical performance, mechanical performance, and cost. A multi-layered temperature control structure can achieve more efficient temperature control.

[0026] This invention has broad application prospects: In the field of power transmission: power cables that can be used in urban power distribution networks, industrial park power supply systems, data center power supply systems, etc., to improve the temperature stability and operational reliability of the cables.

[0027] In the field of new energy vehicles: it can be used in high-voltage cables for new energy vehicles, charging pile cables, etc., to improve the adaptability and safety of cables in environments with large temperature variations.

[0028] In the field of new energy power generation: it can be used in photovoltaic power generation system cables, wind power generation system cables, etc., to improve the service life of cables in harsh outdoor environments.

[0029] Special environment applications: Cables can be used in extreme environments such as polar regions, deserts, and high-temperature industrial environments, expanding the application range of cables.

[0030] Other applications: It can also be used in rail transportation, shipbuilding, aerospace and other applications where high temperature stability of cables is required.

[0031] This invention enables active regulation of cable temperature and efficient storage and reuse of thermal energy, significantly improving the temperature stability, operational reliability and service life of the cable. It is particularly suitable for applications with high requirements for temperature stability, such as medium and low voltage power transmission, high voltage cables for new energy vehicles, and charging pile cables.

[0032] The positive effects of this invention: First, it achieves active regulation and control of cable temperature. By adding phase change material microcapsules to the cable material, utilizing the latent heat storage characteristics of phase change materials, when the cable temperature rises, the phase change material absorbs and stores heat, inhibiting further temperature increases; when the cable temperature drops, the phase change material releases the stored heat to heat the cable and prevent it from becoming too cold. This active temperature control mechanism can significantly reduce the fluctuation range of cable temperature, improve cable temperature stability, and provide a more stable and reliable working environment for power and signal transmission.

[0033] Secondly, it achieves efficient storage and reuse of thermal energy. Through the phase change process of phase change materials, excess heat generated by the cable during operation is stored as latent heat and released when needed (such as during cable startup or heating in low-temperature environments). This realizes the spatiotemporal transfer and reuse of thermal energy, improving energy efficiency and reducing energy consumption. This thermal energy storage and reuse mechanism not only reduces energy waste but can also replace traditional heating equipment in certain situations, simplifying system structure and reducing system costs.

[0034] Third, it improves the cable's adaptability and operational reliability in extreme temperature environments. Through the temperature control and buffering effect of the phase change material, the cable can absorb excess heat in high-temperature environments, preventing the insulation material from softening and aging; and in low-temperature environments, it can release stored heat, preventing the insulation material from becoming brittle and cracking. This temperature adaptability allows the cable to operate stably over a wider temperature range, expanding its application scenarios, especially in extreme environments such as polar regions, deserts, and high-temperature industrial environments.

[0035] Fourth, it extends the service life of the cable. Through the temperature control and buffering effect of the phase change material, the amplitude of cable temperature fluctuations and the frequency of extreme temperatures are reduced. This reduces the thermal stress impact of temperature changes on insulation, conductor, and sheath materials, slows down the aging rate of the materials, and thus extends the service life of the cable, reducing the frequency of cable replacement and maintenance costs.

[0036] Fifth, it offers significant economic and social benefits. Although the manufacturing cost of cables using the technical solution of this invention will increase, the substantial improvements in cable temperature control, operational reliability, and service life, coupled with significantly reduced maintenance costs and energy consumption, result in excellent economic benefits from a total life-cycle cost perspective. Furthermore, the reduced cable failure rate and improved energy efficiency reduce energy waste and environmental pollution, thus providing substantial social benefits. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the working principle of the present invention; In the diagram: 1. Conductor; 2. Phase change temperature control insulation layer; 3. Shielding layer; 4. Phase change temperature control buffer layer; 5. Outer sheath. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0039] An adaptive temperature-controlled wire and cable based on phase change material comprises, from the inside out, a conductor 1, a phase change temperature-controlled insulation layer 2, a shielding layer 3, a phase change temperature-controlled buffer layer 4, and an outer sheath 5. Phase change material microcapsules and thermally conductive reinforcing fillers are dispersed in the phase change temperature-controlled insulation layer 2, the phase change temperature-controlled buffer layer 4, and the outer sheath 5. Each phase change material microcapsule includes a wall material and a core material, where the core material is a phase change material and the wall material is a polymer material. When the cable temperature rises, the phase change material absorbs heat and undergoes a phase change, storing the heat energy as latent heat. When the cable temperature decreases, the phase change material releases heat and undergoes a reverse phase change, releasing the stored heat energy.

[0040] The core material of the phase change material microcapsule comprises one or more of n-alkanes, paraffin wax, fatty acids, and polyethylene glycol, and the wall material comprises one or more of melamine resin, polyurethane, and urea-formaldehyde resin.

[0041] The conductor is made of copper or aluminum, and the shielding layer is made of copper strip, aluminum strip, or woven copper mesh.

[0042] A method for manufacturing an adaptive temperature-controlled wire and cable based on phase change materials, comprising, from the inside out, a conductor 1, a phase change temperature-controlled insulation layer 2, a shielding layer 3, a phase change temperature-controlled buffer layer 4, and an outer sheath 5; phase change material microcapsules and thermally conductive reinforcing fillers are dispersed in the phase change temperature-controlled insulation layer 2, the phase change temperature-controlled buffer layer 4, and the outer sheath 5; the phase change material microcapsules include a wall material and a core material, wherein the core material is a phase change material and the wall material is a polymer material; the particle size of the phase change material microcapsules is 10-100 micrometers, the mass fraction of the phase change material microcapsules in the phase change temperature-controlled insulation layer is 5%-20%, the mass fraction of the phase change material microcapsules in the phase change temperature-controlled buffer layer is 5%-25%, and the mass fraction of the phase change material microcapsules in the outer sheath is 0%-15%; the mass fraction of the thermally conductive reinforcing filler in the phase change temperature-controlled insulation layer is 1%-10%, and the mass fraction of the thermally conductive reinforcing filler in the phase change temperature-controlled buffer layer is 1%-8%.

[0043] The thermally conductive reinforcing filler comprises one or more of expanded graphite, graphene, carbon nanotubes, carbon fibers, and metal powder.

[0044] The phase change temperature control insulation layer uses cross-linked polyethylene, ethylene propylene rubber or silicone rubber as the base material, the phase change temperature control buffer layer uses silicone rubber, thermoplastic elastomer or polyurethane as the base material, and the outer sheath uses polyvinyl chloride, polyethylene or thermoplastic polyurethane as the base material.

[0045] The phase change temperature control insulating layer and the phase change temperature control buffer layer contain microcapsules of various phase change materials with different phase change temperatures, forming a multi-level phase change temperature control structure. The phase change temperature range of the phase change material microcapsules with different phase change temperatures is 20℃-80℃.

[0046] The phase change material microcapsules are prepared by in-situ polymerization, interfacial polymerization or complex condensation.

[0047] The thickness of the phase change temperature control insulation layer is 1.5-5.0 mm, the thickness of the phase change temperature control buffer layer is 0.5-3.0 mm, and the thickness of the outer sheath is 1.0-4.0 mm.

[0048] The cable has an operating temperature range of -40℃ to 125℃. Example 1

[0049] This embodiment provides an adaptive temperature-controlled wire and cable based on phase change material, which is suitable for medium and low voltage power transmission cables, especially for power cables used in urban power distribution networks, industrial park power supply systems, data center power supply systems, etc. The cables in these applications usually carry large currents, generate a lot of heat, and have high requirements for temperature stability and operational reliability.

[0050] Cable structure: such as Figure 1 As shown, the cable structure in this embodiment, from the inside out, consists of: conductor 1, phase change temperature control insulation layer 2, shielding layer 3, phase change temperature control buffer layer 4, and outer sheath 5.

[0051] Material Configuration: The conductor uses copper conductors with a nominal cross-sectional area of ​​185 square millimeters, made of multiple strands of annealed copper wire, with an operating temperature range of -40℃ to 90℃. The phase change temperature control insulation layer uses cross-linked polyethylene (XLPE) material as the matrix, with a thickness of 3.5 mm. Phase change material microcapsules with a particle size of 10-100 micrometers are uniformly dispersed in the phase change temperature control insulation layer. The wall material of the phase change material microcapsules is melamine resin (melamine-formaldehyde resin), and the core material is n-octadecane (phase change temperature approximately 28℃). The mass fraction of the microcapsules is 15% of the total mass of the insulation layer material. Simultaneously, expanded graphite is dispersed in the phase change temperature control insulation layer as a thermally conductive reinforcing filler, with a mass fraction of 5% of the total mass of the insulation layer material. The shielding layer uses aluminum tape with a thickness of 0.12 mm, overlapped and wrapped, with an overlap rate of not less than 15%. The phase change temperature control buffer layer uses silicone rubber material as the matrix, with a thickness of 1.5 mm. Phase change material microcapsules are uniformly dispersed in the phase change temperature control buffer layer. The phase change material microcapsules have polyurethane wall material and a paraffin mixture (phase change temperature approximately 40°C) core material. The microcapsules comprise 20% of the total mass of the buffer layer material. Simultaneously, carbon fibers are dispersed within the phase change temperature-controlled buffer layer as a thermally conductive reinforcing filler, comprising 3% of the total mass of the buffer layer material. The outer sheath is made of polyvinyl chloride (PVC) material with a thickness of 2.5 mm. Phase change material microcapsules are added to the outer sheath, comprising 10% of the total mass of the sheath material.

[0052] Preparation method: ① Preparation of phase change material microcapsules. Microcapsules coated with n-octadecane by melamine resin were prepared by in-situ polymerization. Melamine resin prepolymer and n-octadecane were mixed and formed into a water-in-oil emulsion under high-speed shear emulsification conditions. The pH and temperature were adjusted to allow the melamine resin to polymerize on the surface of the n-octadecane droplets to form a dense capsule wall. After filtration, washing and drying, phase change microcapsules with a particle size of 10-100 micrometers were obtained.

[0053] ②Preparation of phase change temperature-controlled insulation and buffer layer materials. Phase change microcapsules, thermally conductive reinforcing fillers, and matrix materials (XLPE or silicone rubber) are mixed evenly in an internal mixer, and the mixing temperature is controlled to be lower than the phase change temperature of the phase change material to prevent the phase change material from undergoing a phase change prematurely.

[0054] ③ Cable manufacturing. A three-layer co-extrusion technology is used to simultaneously extrude the conductor, phase change temperature-controlled insulation layer, and shielding layer. Then, a phase change temperature-controlled buffer layer is wrapped or extruded, and finally, the outer sheath is extruded. The extrusion temperature and cooling rate are controlled to ensure that the phase change material microcapsules do not rupture or leak during the extrusion process.

[0055] Working principle: such as Figure 2 As shown, during cable operation, the conductor generates heat due to the current flowing through it, and this heat is transferred to the phase change temperature-controlled insulation layer via thermal conduction. When the temperature of the phase change temperature-controlled insulation layer rises above the phase change temperature of the phase change material, the phase change material begins to absorb heat and undergoes a solid-liquid phase change, storing the thermal energy as latent heat and inhibiting further temperature increases in the phase change temperature-controlled insulation layer. When the cable load decreases or the ambient temperature drops, and the temperature of the phase change temperature-controlled insulation layer falls below the phase change temperature of the phase change material, the phase change material releases the stored heat and undergoes a liquid-solid phase change, providing heating for the phase change temperature-controlled insulation layer and preventing it from becoming too cold. Through this phase change energy storage and heat release mechanism, active regulation and buffering of cable temperature are achieved, reducing the impact of temperature fluctuations on cable performance and improving the operational reliability and service life of the cable. Example 2

[0056] This embodiment provides an adaptive temperature-controlled wire and cable based on phase change material, which is suitable for cables in new energy fields such as high-voltage cables for new energy vehicles, charging pile cables, and photovoltaic power generation system cables. Cables in these applications typically operate in environments with large temperature variations and have high requirements for temperature adaptability and safety.

[0057] Cable structure: Similar to Embodiment 1, the cable structure in this embodiment consists of the following components from the inside out: conductor 1, phase change temperature control insulation layer 2, shielding layer 3, phase change temperature control buffer layer 4, and outer sheath 5.

[0058] Material Configuration: The conductor uses tin-plated copper conductors with a nominal cross-sectional area of ​​50 square millimeters, composed of multiple strands of tin-plated copper wire, with an operating temperature range of -40℃ to 125℃. The phase change temperature control insulation layer uses cross-linked polyethylene (XLPE) material as the matrix, with a thickness of 2.0 mm, and phase change material microcapsules are uniformly dispersed in the phase change temperature control insulation layer. This embodiment adopts a multi-level phase change temperature design, including low-temperature phase change microcapsules (phase change temperature approximately 25℃, phase change material is n-eicosane, mass fraction 5%), medium-temperature phase change microcapsules (phase change temperature approximately 45℃, phase change material is n-tetracosane, mass fraction 5%), and high-temperature phase change microcapsules (phase change temperature approximately 65℃, phase change material is n-octacosane, mass fraction 5%). Simultaneously, graphene nanosheets are dispersed in the phase change temperature control insulation layer as a thermally conductive reinforcing filler, with the mass fraction of graphene being 2% of the total mass of the insulation layer material. The shielding layer uses a tin-plated copper wire braided layer with a braiding density of not less than 85%. The phase change temperature control buffer layer uses thermoplastic elastomer (TPE) material as the matrix, with a thickness of 1.0 mm. Phase change material microcapsules are uniformly dispersed within the buffer layer, employing a multi-level phase change temperature design, including low-temperature phase change microcapsules (8% by mass), medium-temperature phase change microcapsules (8% by mass), and high-temperature phase change microcapsules (8% by mass). Simultaneously, carbon nanotubes are dispersed within the buffer layer as a thermally conductive reinforcing filler, with the carbon nanotubes accounting for 1% of the total mass of the buffer layer material. The outer sheath uses thermoplastic polyurethane (TPU) material, with a thickness of 1.5 mm. Flame retardants and anti-aging agents are added to the outer sheath to improve the cable's flame retardant and weather resistance properties.

[0059] Preparation method: ① Preparation of phase change material microcapsules with multiple phase change temperatures. Using an in-situ polymerization method similar to that in Example 1, phase change material microcapsules with different phase change temperatures were prepared. By selecting n-alkanes with different carbon chain lengths (such as n-eicosane, n-tetracosane, and n-octacosane) as core materials, microcapsules with different phase change temperatures were obtained.

[0060] ②Preparation of phase change temperature-controlled insulation layer and phase change temperature-controlled buffer layer materials. Microcapsules of phase change materials with different phase change temperatures are mixed in a certain proportion, and then mixed evenly with thermally conductive reinforcing fillers and matrix materials (XLPE or TPE) in an internal mixer. The mixing temperature is controlled to be lower than the minimum phase change temperature (about 20°C) to prevent the phase change materials from undergoing phase change prematurely.

[0061] ③ Cable manufacturing. A three-layer co-extrusion technology is used to simultaneously extrude the conductor, phase change temperature-controlled insulation layer, and shielding layer, then the phase change temperature-controlled buffer layer is extruded, and finally the outer sheath is extruded, controlling the extrusion temperature and cooling rate.

[0062] Working Principle: Similar to Example 1, during cable operation, the heat generated by the conductor is transferred to the phase change temperature-controlled insulation layer through heat conduction. When the temperature of the phase change temperature-controlled insulation layer rises, phase change materials with different phase change temperatures undergo phase changes successively, absorbing and storing heat to suppress further temperature increases. When the temperature of the phase change temperature-controlled insulation layer decreases, phase change materials with different phase change temperatures release the stored heat, providing heating for the insulation layer and preventing it from becoming too cold. Through this multi-stage phase change energy storage and heat release mechanism, a wide range of cable temperature regulation and buffering is achieved, significantly improving the cable's adaptability and operational reliability in environments with large temperature variations.

[0063] Technical Advantages: In this embodiment, a multi-stage phase change temperature design is employed to expand the temperature control range and capability of the cable. When the cable temperature is low (e.g., 20-30℃), the low-temperature phase change microcapsules undergo phase change first, absorbing or releasing heat. As the cable temperature continues to rise or fall, the medium- and high-temperature phase change microcapsules undergo phase change successively, forming a continuous temperature control range, achieving wide-range temperature regulation and buffering of the cable. This multi-stage phase change temperature design can significantly improve the cable's temperature control capability and temperature adaptability, making it suitable for applications with large temperature variation ranges. Furthermore, by adding high thermal conductivity fillers such as graphene nanosheets and carbon nanotubes, an efficient thermally conductive network can be constructed in the cable material, improving the heat transfer efficiency of the phase change material, shortening the response time of the phase change material, enabling the phase change material to respond to temperature changes more quickly, and improving the dynamic performance of the temperature control system.

[0064] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An adaptive temperature-controlled wire and cable based on phase change material, characterized in that: From the inside out, it includes a conductor (1), a phase change temperature control insulation layer (2), a shielding layer (3), a phase change temperature control buffer layer (4), and an outer sheath (5); phase change material microcapsules and thermally conductive reinforced fillers are dispersed in the phase change temperature control insulation layer (2), the phase change temperature control buffer layer (4), and the outer sheath (5); the phase change material microcapsules include a wall material and a core material, the core material is a phase change material, and the wall material is a polymer material; When the cable temperature rises, the phase change material absorbs heat and undergoes a phase change, storing the thermal energy in the form of latent heat; when the cable temperature decreases, the phase change material releases heat and undergoes a reverse phase change, releasing the stored thermal energy.

2. The adaptive temperature-controlled wire and cable based on phase change material according to claim 1, characterized in that: The core material of the phase change material microcapsule comprises one or more of n-alkanes, paraffin wax, fatty acids, and polyethylene glycol, and the wall material comprises one or more of melamine resin, polyurethane, and urea-formaldehyde resin.

3. The adaptive temperature-controlled wire and cable based on phase change material according to claim 2, characterized in that: The conductor is made of copper or aluminum, and the shielding layer is made of copper strip, aluminum strip, or woven copper mesh.

4. A method for manufacturing an adaptive temperature-controlled wire and cable based on phase change materials, characterized in that: The structure, from the inside out, comprises a conductor (1), a phase change temperature control insulation layer (2), a shielding layer (3), a phase change temperature control buffer layer (4), and an outer sheath (5). Phase change material microcapsules and thermally conductive reinforcing fillers are dispersed within the phase change temperature control insulation layer (2), the phase change temperature control buffer layer (4), and the outer sheath (5). Each phase change material microcapsule includes a wall material and a core material; the core material is a phase change material, and the wall material is a polymer material. The particle size of the phase change material microcapsules is 10-100 micrometers. The mass fraction of the phase change material microcapsules in the phase change temperature control insulation layer is 5%-20%, the mass fraction in the phase change temperature control buffer layer is 5%-25%, and the mass fraction in the outer sheath is 0%-15%. The mass fraction of the thermally conductive reinforcing filler in the phase change temperature control insulation layer is 1%-10%, and the mass fraction in the phase change temperature control buffer layer is 1%-8%.

5. The manufacturing method of an adaptive temperature-controlled wire and cable based on phase change material according to claim 4, characterized in that: The thermally conductive reinforcing filler comprises one or more of expanded graphite, graphene, carbon nanotubes, carbon fibers, and metal powder; the phase change temperature control insulation layer uses cross-linked polyethylene, ethylene propylene rubber, or silicone rubber as the matrix material; the phase change temperature control buffer layer uses silicone rubber, thermoplastic elastomer, or polyurethane as the matrix material; and the outer sheath uses polyvinyl chloride, polyethylene, or thermoplastic polyurethane as the matrix material.

6. The manufacturing method of an adaptive temperature-controlled wire and cable based on phase change material according to claim 4, characterized in that: The phase change temperature control insulating layer and the phase change temperature control buffer layer contain microcapsules of various phase change materials with different phase change temperatures, forming a multi-level phase change temperature control structure. The phase change temperature range of the phase change material microcapsules with different phase change temperatures is 20℃-80℃.

7. The manufacturing method of an adaptive temperature-controlled wire and cable based on phase change material according to claim 4, characterized in that: The phase change material microcapsules are prepared by in-situ polymerization, interfacial polymerization or complex condensation.

8. The manufacturing method of an adaptive temperature-controlled wire and cable based on phase change material according to claim 4, characterized in that: The thickness of the phase change temperature control insulation layer is 1.5-5.0 mm, the thickness of the phase change temperature control buffer layer is 0.5-3.0 mm, and the thickness of the outer sheath is 1.0-4.0 mm.

9. A method for manufacturing an adaptive temperature-controlled wire and cable based on phase change material according to claim 4, characterized in that... Specific steps: ① Preparation of phase change material microcapsules; Microcapsules coated with n-octadecane by melamine resin were prepared by in-situ polymerization. Melamine resin prepolymer was mixed with n-octadecane and water-in-oil emulsion was formed under high-speed shear emulsification. The pH and temperature were adjusted to polymerize melamine resin on the surface of n-octadecane droplets to form a dense capsule wall. After filtration, washing and drying, phase change microcapsules with a particle size of 10-100 micrometers were obtained. ②Prepare phase change temperature control insulation layer and phase change temperature control buffer layer materials; mix phase change material microcapsules, thermally conductive enhanced fillers and matrix materials evenly in an internal mixer, and control the mixing temperature to be lower than the phase change temperature of the phase change material to avoid premature phase change of the phase change material; ③ Cable manufacturing: The three-layer co-extrusion technology is used to simultaneously extrude the conductor, phase change temperature-controlled insulation layer and shielding layer, then wrap or extrude the phase change temperature-controlled buffer layer, and finally extrude the outer sheath. The extrusion temperature and cooling rate are controlled to ensure that the phase change material microcapsules will not rupture or leak during the extrusion process.

10. A method for manufacturing an adaptive temperature-controlled wire and cable based on phase change material according to claim 4, characterized in that: Specific steps: ①Preparation of phase change material microcapsules with multiple phase change temperatures; Phase change material microcapsules with different phase change temperatures were prepared by in-situ polymerization. By selecting n-alkanes with different carbon chain lengths as core materials, microcapsules with different phase change temperatures were obtained. ②Preparation of phase change temperature control insulation layer and phase change temperature control buffer layer materials; mixing microcapsules of phase change materials with different phase change temperatures, and mixing them evenly with thermally conductive reinforcing fillers and matrix materials in an internal mixer, controlling the mixing temperature to be lower than the minimum phase change temperature to avoid premature phase change of the phase change materials; ③ Cable manufacturing: The three-layer co-extrusion technology is used to simultaneously extrude the conductor, phase change temperature-controlled insulation layer and shielding layer, then the phase change temperature-controlled buffer layer is extruded, and finally the outer sheath is extruded, controlling the extrusion temperature and cooling rate.

Images