Weather-resistant and crack-resistant aluminum alloy power cable

Abstract

The invention, which relates to the technical field of the power cable, provides a weather-resistant and crack-resistant aluminum alloy power cable comprising an alloy conductor layer, a shielding layer, an insulating layer and a protective layer. The alloy conductor layer comprises an inner conductive core and a plurality of outer conductive cores, the outer conductive cores are spirally wound and attached to the outer wall of the inner conductive core, the shielding layer is arranged on the outer sides of the outer conductive cores, the hardness of the inner conductive cores is lower than that of the outer conductive cores, the conductivity coefficient of the inner conductive cores is higher than that of the outer conductive cores, and the outer conductive cores are made of aluminum alloy; the insulating layer comprises an inner insulating layer and an outer insulating layer, an elastic reinforcing layer is arranged between the inner insulating layer and the outer insulating layer, the protective layer is arranged on the outer side of the outer insulating layer, and a buffer connecting layer is arranged between the inner insulating layer and the shielding layer. The cable has high conductivity, meanwhile, the anti-cracking and anti-corrosion capability of the surface of the conductor is remarkably improved, and the connection tightness between cable structures is ensured.

Description

Technical Field

[0001] This invention relates to the field of power cable technology, and in particular to a weather-resistant and crack-resistant aluminum alloy power cable. Background Technology

[0002] As the core carrier of electrical energy transmission, the reliability of power cables directly affects the safe and stable operation of the power grid and the quality of power supply. With the rapid advancement of the State Grid construction, especially the upgrading of urban distribution networks, the grid connection of new energy power generation (such as photovoltaic and wind farms), and the construction of power facilities in harsh environments such as coastal areas, high-altitude cold regions, and high-humidity areas, higher requirements are placed on the environmental adaptability and long-term service life of power cables. Aluminum alloy conductor cables, due to their advantages such as light weight, relatively low cost, and convenient installation, have been increasingly widely used in the field of power transmission, especially in medium and low voltage distribution networks, becoming an important alternative to traditional copper cables. However, traditional aluminum alloy cables suffer from the following structural defects: First, the problem of stress concentration in homogeneous conductors is prominent. When conventional aluminum alloy stranded conductors of equal hardness undergo bending vibration, surface stress cannot be effectively dispersed inwards, leading to preferential initiation of fatigue cracks in the conductive core. Under the penetration of salt spray / industrial corrosive media, this further induces intergranular stress corrosion cracking, causing sudden core breakage accidents. Second, thermal expansion mismatch is severe. The difference in linear expansion coefficients between the conductor and insulation layer generates interfacial shear stress under diurnal temperature cycle, accelerating the peeling of the insulation layer from the conductor. Furthermore, the existing cable's buffer connection structure is simple and cannot effectively absorb mechanical vibration energy, leading to relative displacement between the shielding layer and the insulation layer, affecting signal transmission stability. Simultaneously, the insulation layer's bending resistance is insufficient, easily generating microcracks under repeated bending conditions, ultimately leading to insulation failure. These defects severely restrict the long-term reliable operation of aluminum alloy cables in complex environments. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of this invention is to provide a weather-resistant and crack-resistant aluminum alloy power cable that can solve the technical problems of stress concentration and thermal expansion mismatch in the homogeneous conductor of aluminum alloy power cables in the prior art.

[0004] This invention provides a weather-resistant and crack-resistant aluminum alloy power cable, comprising: an alloy conductor layer, a shielding layer, an insulation layer, and a protective layer; The alloy conductor layer includes an inner conductive core and multiple outer conductive cores. The outer conductive cores are spirally wound and attached to the outer wall of the inner conductive core. The shielding layer is disposed on the outside of the outer conductive core. The hardness of the inner conductive core is lower than that of the outer conductive core, and the conductivity of the inner conductive core is higher than that of the outer conductive core. The outer conductive core is made of aluminum alloy. The insulating layer includes an inner insulating layer and an outer insulating layer, with an elastic reinforcing layer between the inner insulating layer and the outer insulating layer. The protective layer is disposed outside the outer insulating layer, and a buffer connection layer is disposed between the inner insulating layer and the shielding layer. The buffer connection layer includes outer fasteners uniformly disposed on the outer surface of the shielding layer and inner fasteners uniformly disposed inside the inner insulation layer. Meanwhile, an inner filling layer tightly fills the space between the shielding layer and the inner insulation layer, and the outer fasteners and inner fasteners are embedded together inside the inner filling layer.

[0005] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: (1) In the embodiments of the present invention, the alloy conductor layer is divided into an inner conductive core and multiple outer conductive cores. The inner conductive core is a flexible alloy with high energy absorption effect, and the outer conductive core is a high-strength hard core with crack resistance. This structure not only ensures conductivity, but also significantly improves the crack resistance and corrosion resistance of the conductor surface.

[0006] (2) In the embodiments of the present invention, the designed buffer connection layer has the effect of mechanical anchoring to suppress interlayer displacement, thereby avoiding the phenomenon of accelerated peeling of the insulation layer and the conductor due to the difference in the linear expansion coefficients of the conductor and the insulation layer under the interfacial shear stress generated by the day and night temperature difference cycle. Attached Figure Description

[0007] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0008] Figure 1 This is a schematic diagram of the structure of a weather-resistant and crack-resistant aluminum alloy power cable provided in an embodiment of the present invention.

[0009] Figure 2 This is a schematic diagram of the disassembled structure of the fastening sleeve and the outer conductive core in a weather-resistant and crack-resistant aluminum alloy power cable provided by an embodiment of the present invention.

[0010] Figure 3 This is a schematic diagram of the split structure of the buffer connection layer of a weather-resistant and crack-resistant aluminum alloy power cable provided in an embodiment of the present invention.

[0011] Figure 4 This is a cross-sectional view of the buffer connection layer of a weather-resistant and crack-resistant aluminum alloy power cable provided in an embodiment of the present invention.

[0012] Figure 5 This is a cross-sectional view of the elastic reinforcing layer of a weather-resistant and crack-resistant aluminum alloy power cable provided in an embodiment of the present invention.

[0013] Figure 6 This is a structural diagram showing the distribution of elastic node reinforcements in a weather-resistant and crack-resistant aluminum alloy power cable according to an embodiment of the present invention.

[0014] Figure 7 This is a schematic diagram of the outer filling layer structure of a weather-resistant and crack-resistant aluminum alloy power cable provided in an embodiment of the present invention.

[0015] Figure 8 This is a schematic diagram of an elastic node reinforcement structure for a weather-resistant and crack-resistant aluminum alloy power cable provided in an embodiment of the present invention.

[0016] Figure 9 This is a schematic diagram of the connection structure between the outer fastener and the reinforcing rib of a weather-resistant and crack-resistant aluminum alloy power cable provided in an embodiment of the present invention.

[0017] Explanation of reference numerals in the attached drawings: 1-Inner conductive core; 2-Outer conductive core; 3-Fastening sleeve; 4-Elastic reinforcing member; 5-Outer filling layer; 6-Outer insulation layer; 7-Reinforcing strip; 8-Weather-resistant sheath layer; 9-Barrier layer; 10-Adhesive layer; 11-Inner insulation layer; 12-Inner filling layer; 13-Shielding layer; 14-Outer fastener; 15-Outer ring; 16-Inner fastener; 17-Fastening groove; 18-Reinforcing rib; 19-Elastic connecting post; 20-Inner ring. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0019] Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts disclosed in this invention.

[0020] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention.

[0021] Reference manual attached Figures 1 to 9 The present invention provides a weather-resistant and crack-resistant aluminum alloy power cable, comprising: an alloy conductor layer, a shielding layer 13, an insulation layer, and a protective layer.

[0022] The alloy conductor layer includes an inner conductive core 1 and multiple outer conductive cores 2. The outer conductive cores 2 are spirally wound and attached to the outer wall of the inner conductive core 1. The shielding layer 13 is disposed on the outside of the outer conductive core 2. The hardness of the inner conductive core 1 is lower than that of the outer conductive core 2, and the conductivity of the inner conductive core 1 is higher than that of the outer conductive core 2. The outer conductive core 2 is made of aluminum alloy.

[0023] The insulation layer includes an inner insulation layer 11 and an outer insulation layer 6. An elastic reinforcing layer is provided between the inner insulation layer 11 and the outer insulation layer 6. A protective layer is provided outside the outer insulation layer 6. At the same time, a buffer connection layer is provided between the inner insulation layer 11 and the shielding layer 13.

[0024] The buffer connection layer includes outer fasteners 14 uniformly disposed on the outer surface of the shielding layer 13 and inner fasteners 16 uniformly disposed inside the inner insulation layer 11. The outer fasteners 14 and inner fasteners 16 are staggered. At the same time, the shielding layer 13 and the inner insulation layer 11 are tightly filled with an inner filling layer 12. The outer fasteners 14 and inner fasteners 16 are embedded in the inner filling layer 12. Reinforcing ribs 18 are embedded in both the outer fasteners 14 and the inner fasteners 16. The two ends of the reinforcing ribs 18 extend into the adjacent shielding layer 13 or inner insulation layer 11. The reinforcing ribs 18 can increase the connection strength of the fasteners.

[0025] The inner conductive core 1 of the alloy conductor layer refers to a conductor with low hardness located at the center of the cable. It can be made of pure aluminum or high-purity aluminum alloy, and its high conductivity reduces the overall resistance of the cable. The outer conductive core 2 refers to an aluminum alloy wire spirally wound around the outer periphery of the inner conductive core 1. It can be made of aluminum alloy with added magnesium and silicon elements, and its higher hardness improves bending resistance. The shielding layer 13 is a conductive layer covering the outer side of the outer conductive core 2. It can be formed by wrapping with copper tape or aluminum-plastic composite tape and is used to suppress electromagnetic interference. The inner insulation layer 11 and the outer insulation layer 6 refer to polymer material layers covering the outer side of the shielding layer 13 and the outer side of the elastic reinforcing layer, respectively. They can be made of cross-linked polyethylene or silicone rubber and provide electrical insulation protection. The elastic reinforcing layer is a buffer structure set between the inner and outer insulation layers to absorb mechanical deformation. The buffer connection layer uses a snap-fit ​​component consisting of an outer fastener 14 and an inner fastener 16, which are mechanically interlocked by the adhesive effect of the inner filling layer 12.

[0026] Specifically, the inner conductive core 1 serves as the conductive core of the cable, and its high conductivity reduces power transmission loss. The outer conductive core 2 is tightly wound in a spiral manner around the surface of the inner conductive core, forming a mechanical support structure. When the cable bends, the geometric characteristics of the spiral winding disperse stress. The shielding layer 13 tightly covers the outer conductive core 2, suppressing corona discharge on the conductor surface and external electromagnetic interference. The elastic reinforcing layer between the inner insulation layer 11 and the outer insulation layer 6 absorbs the difference in thermal expansion between the inner and outer layer materials through elastic deformation when the temperature changes, preventing the insulation layer from cracking. In the buffer connection layer between the shielding layer 13 and the inner insulation layer 11, the outer fastener 14 and the inner fastener 16 form a three-dimensional interlocking structure under the bonding action of the inner filling layer 12, effectively resisting interlayer shear force. The inner filling layer 12 is made of silicone material with an elastic modulus between that of the shielding layer 13 and the insulation layer, uniformly transferring stress and compensating for manufacturing tolerances.

[0027] Multiple outer conductive cores 2 are fitted with a fastening sleeve 3 on their outer sides. The inner wall of the fastening sleeve 3 is provided with a fastening groove 17 that matches the outer conductive cores 2. The fastening sleeve 3 can be made of metal or polymer material through extrusion molding process. It is used to constrain the radial displacement of the outer conductive cores 2 and prevent relative sliding between the conductive cores during bending vibration.

[0028] Among them, the fastening groove 17 is a groove structure distributed circumferentially along the inner wall of the fastening sleeve 3. Specifically, it can be formed by mold processing into a continuous or intermittent groove that is consistent with the cross-sectional shape of the outer conductive core 2. It is used to embed the outer conductive core 2 and form a tight contact with its surface to avoid uneven stress distribution due to the gap of the contact surface.

[0029] The outer surface of the fastening sleeve 3 is provided with a groove structure, and the shielding layer 13 is tightly attached to the outer surface of the fastening sleeve 3.

[0030] When the shielding layer 13 is applied to the surface of the grooved sleeve 3, the uneven contour formed by the groove structure forces the shielding material to fill the grooved areas during the forming process, creating a mechanical interlock. When the cable is subjected to bending or vibration loads, the multi-point anchoring effect generated by the groove structure can disperse shear stress and prevent relative slippage between the shielding layer and the conductor layer. Under temperature cycling conditions, the additional contact area provided by the groove structure can compensate for dimensional changes caused by differences in the thermal expansion coefficients of the materials, maintaining the stability of the interfacial bonding.

[0031] The elastic reinforcing layer includes an outer filling layer 5 filled between the inner insulation layer 11 and the outer insulation layer 6. Multiple elastic reinforcing members 4 are equidistantly embedded inside the outer filling layer 5. The elastic reinforcing members 4 are sleeved on the outside of the inner insulation layer 11. Several elastic node reinforcing members are equidistantly arranged between the inner insulation layer 11 and the outer insulation layer 6. The elastic node reinforcing member includes an outer ring member 15 embedded inside the outer insulation layer 6. An inner ring member 20 is embedded in the inner insulation layer 11 at the corresponding position of the outer ring member 15. Several elastic connecting posts 19 are uniformly connected between the outer ring member 15 and the inner ring member 20. The elastic connecting posts 19 are embedded inside the outer filling layer 5. The elastic reinforcing members 4 are arranged between adjacent elastic node reinforcing members and are spring-shaped.

[0032] The outer filler layer 5 forms a uniform stress buffer interface by continuously wrapping the inner insulation layer 11. Elastic reinforcing members 4 are embedded within the outer filler layer 5 at equal intervals, forming a stiffness gradient distributed along the cable axis. When the cable is subjected to bending or temperature changes, the elastic deformation of the outer filler layer 5 absorbs the displacement difference between the conductor and the insulation layer. The elastic reinforcing members 4 provide support to the outer filler layer 5 through their own deformation, preventing excessive local stress concentration. The design of the elastic reinforcing members 4, fitted outside the inner insulation layer 11, not only constrains the radial expansion of the inner insulation layer 11 but also counteracts the compressive load applied by the outer insulation layer 6 through elastic restoring force, thereby maintaining the overall stability of the insulation layer structure.

[0033] The outer ring 15 is a ring-shaped support structure that forms a mechanical anchor with the outer insulation layer 6. It can be made of metal or polymer composite material and is combined with the outer insulation layer 6 through a pre-embedded molding process to disperse interfacial shear stress. The inner ring 20 is a ring structure that forms an embedded connection with the inner insulation layer 11. It can be made of the same or different material as the outer ring and is fixed inside the inner insulation layer 11 through injection molding or press fitting. It is used to provide docking support with the elastic connecting post 19. The elastic connecting post 19 is a columnar elastic element that connects the outer ring 15 and the inner ring 20. It can be made of rubber or silicone material and is integrally molded with the outer ring 15 and the inner ring 20 through a molding process to absorb deformation caused by thermal expansion difference and maintain interlayer bonding force.

[0034] Specifically, when the cable undergoes axial expansion or bending deformation due to temperature changes, the outer ring 15 and inner ring 20 form a multi-level buffer node through the tensile or compressive action of the elastic connecting posts 19. The elastic connecting posts 19 are evenly distributed at the interlayer interface, allowing thermal stress to be dispersed and transmitted circumferentially, preventing localized stress concentration that could lead to insulation peeling. The outer filling layer 5 further restricts excessive deformation of the elastic connecting posts 19, ensuring the stability of the interlayer structure under dynamic loads.

[0035] The protective layer includes a weather-resistant sheath layer 8, a barrier layer 9, and an adhesive layer 10. The barrier layer 9 is tightly fitted onto the outside of the outer insulation layer 6 through the adhesive layer 10, while the weather-resistant sheath layer 8 is tightly fitted onto the outside of the barrier layer 9.

[0036] Among them, the weather-resistant sheath layer 8 is a protective structure wrapped around the outermost layer of the cable to resist ultraviolet rays, temperature changes and mechanical wear. Specifically, it can be achieved by using cross-linked polyethylene or polyvinyl chloride composite materials. Its high weather resistance can slow down the aging of materials caused by long-term exposure to the outdoor environment.

[0037] The barrier layer 9 is a penetration-proof structure, which can be achieved by using aluminum-plastic composite tape or galvanized steel tape laminate. Its dense structure can prevent moisture, salt spray and chemical corrosive media from penetrating into the cable.

[0038] The adhesive layer 10 is an intermediate layer used to bond the barrier layer 9 to the outer insulation layer 6. Specifically, it can be achieved by using ethylene-vinyl acetate copolymer hot melt adhesive or polyurethane adhesive. Its flexible properties can buffer the interlayer stress caused by temperature changes.

[0039] The barrier layer 9 is continuously wrapped with the outer insulation layer 6 through the adhesive layer 10. After curing, the adhesive layer 10 generates a uniform interfacial bonding force, ensuring a gapless fit between the barrier layer 9 and the outer insulation layer 6. The weather-resistant sheath layer 8 is applied to the surface of the barrier layer 9 through an extrusion molding process, forming a complete outer protection system. When the cable is subjected to external environmental corrosion, the barrier layer 9 effectively isolates corrosive media, the adhesive layer 10 absorbs the shear stress caused by the difference in thermal expansion between the conductor and the insulation layer through elastic deformation, and the weather-resistant sheath layer 8 maintains the integrity of the outer structure through its UV resistance and tear resistance.

[0040] Multiple reinforcing strips 7 are integrally formed on the outer surface of the weather-resistant sheath layer 8, and the reinforcing strips 7 are arranged in a spiral pattern. Multiple spiral reinforcing strips 7 are simultaneously formed on the outer surface of the weather-resistant sheath layer through a co-extrusion process. When the cable is subjected to external mechanical loads, the spirally distributed reinforcing strips 7 can evenly distribute local stress along the spiral direction to the entire weather-resistant sheath layer 8, preventing stress concentration that could lead to cracking of the weather-resistant sheath layer 8. When the cable undergoes axial expansion and contraction due to temperature changes, the geometry of the spiral reinforcing strips 7 allows the weather-resistant sheath layer 8 to undergo coordinated deformation in the axial and radial directions, thereby reducing the risk of interlayer delamination due to differences in thermal expansion. This effectively suppresses cracking of the weather-resistant sheath layer 8 caused by mechanical or thermal stress in harsh environments, enhancing the long-term service reliability of the cable under severe conditions such as high salt spray and extreme temperature cycling in coastal areas, while also avoiding the risk of insulation corrosion due to damage to the weather-resistant sheath layer 8.

[0041] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the preferred embodiments, while those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the protection scope of the present invention.

Claims

1. A weathering and cracking resistant aluminum alloy power cable characterized by, The alloy conductor layer, the shielding layer (13), the insulation layer and the protective layer are included. The alloy conductor layer includes an inner conductive core (1) and a plurality of outer conductive cores (2), the outer conductive cores (2) are spirally wound and attached to the outer wall of the inner conductive core (1), the shielding layer (13) is arranged outside the outer conductive core (2), the hardness of the inner conductive core (1) is lower than that of the outer conductive core (2), and the conductivity of the inner conductive core (1) is higher than that of the outer conductive core (2), and the outer conductive core (2) is made of aluminum alloy material. The insulation layer includes an inner insulation layer (11) and an outer insulation layer (6), an elastic reinforcing layer is arranged between the inner insulation layer (11) and the outer insulation layer (6), and a buffer connecting layer is arranged between the inner insulation layer (11) and the shielding layer (13). The buffer connecting layer includes outer buckles (14) uniformly arranged on the outer surface of the shielding layer (13) and inner buckles (16) uniformly arranged inside the inner insulation layer (11), and the shielding layer (13) and the inner insulation layer (11) are tightly filled with an inner filling layer (12), and the outer buckles (14) and the inner buckles (16) are jointly embedded in the inner filling layer (12). A plurality of outer conductive cores (2) are jointly sleeved with a fastening sleeve (3) outside, and the inner wall of the fastening sleeve (3) is provided with a fastening groove (17) matched with the outer conductive core (2).

2. The weathering and cracking resistant aluminum alloy power cable of claim 1, wherein, The outer surface of the fastening sleeve (3) is provided with a groove structure, and the shielding layer (13) is tightly attached to the outer surface of the fastening sleeve (3).

3. The weathering and cracking resistant aluminum alloy power cable of claim 2, wherein, The elastic reinforcing layer includes an outer filling layer (5) filled between the inner insulation layer (11) and the outer insulation layer (6), a plurality of elastic reinforcing members (4) are equally embedded in the inner insulation layer (11) outside the outer filling layer (5).

4. The weathering and cracking resistant aluminum alloy power cable of claim 1, wherein, A plurality of elastic node reinforcing members are equally arranged between the inner insulation layer (11) and the outer insulation layer (6), the elastic node reinforcing member includes an outer ring member (15) embedded in the outer insulation layer (6), an inner ring member (20) is embedded in the inner insulation layer (11) at the corresponding position of the outer ring member (15), and a plurality of elastic connecting columns (19) are uniformly connected between the outer ring member (15) and the inner ring member (20), and the elastic connecting column (19) is embedded in the outer filling layer (5).

5. The weathering and cracking resistant aluminum alloy power cable of claim 4, wherein, The elastic reinforcing member (4) is arranged between adjacent elastic node reinforcing members, and the elastic reinforcing member (4) is arranged in a spring shape.

6. The weathering and cracking resistant aluminum alloy power cable of claim 5, wherein, The protective layer includes a weatherproof sheath layer (8), a barrier layer (9) and an adhesive layer (10), the barrier layer (9) is tightly sleeved outside the outer insulation layer (6) through the adhesive layer (10), and the weatherproof sheath layer (8) is tightly sleeved outside the barrier layer (9).

7. The weathering and cracking resistant aluminum alloy power cable of claim 1, wherein, The inner buckles (16) and the outer buckles (14) are embedded with reinforcing ribs (18), and the reinforcing ribs (18) extend to the inside of the adjacent shielding layer (13) or inner insulation layer (11) at both ends.

8. The weathering and cracking resistant aluminum alloy power cable of claim 1, wherein, The outer buckles (14) and the inner buckles (16) are arranged in a staggered manner.

9. The weathering and cracking resistant aluminum alloy power cable of claim 1, wherein, ​ 10. The weathering and cracking resistant aluminum alloy power cable of claim 7, wherein, The outer surface of the weather-resistant sheath layer (8) is integrally formed with a plurality of reinforcing strips (7), and the reinforcing strips (7) are arranged in a spiral shape.

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