Lightweight overhead line for high altitude

Abstract

The application discloses a light overhead line for high altitude, which comprises a conductor made of high-conductivity aluminum alloy, and the cross section of the conductor is low-speed airfoil shape. The application breaks the inherent traditional thinking, optimizes the material of the conductor to reduce the self weight, and innovatively optimizes the cross section of the conventional conductor from a circle to a low-speed airfoil shape. In combination with the existing high-conductivity aluminum alloy material, when the conductor is used overhead, the Bernoulli effect is utilized to generate lift to offset part of the self weight of the overhead line, so that the safety of the line is enhanced. Meanwhile, the cross section structure of the low-speed airfoil shape increases the surface area of the conductor, which is more conducive to heat dissipation of the conductor, so that the current-carrying capacity of the line is increased, and the power loss of the long-distance power transmission line is reduced.

Description

Technical Field

[0001] This invention relates to the field of wire and cable technology, and in particular to a lightweight overhead line for high-altitude applications. Background Technology

[0002] Overhead lines mainly refer to exposed overhead lines, erected above the ground. Insulators secure the transmission conductors to towers standing upright on the ground to transmit electrical energy. They are relatively easy to install and maintain, and have lower costs. Typically, the power conductors used in overhead lines have no insulating material covering their metal conductors; these are "bare wires," directly exposed to the air. This results in high heat dissipation efficiency, allowing for high current transmission. Furthermore, the lack of insulation and sheathing reduces the load on the towers and lowers the cost of the supporting structure. Bare wires also make it easy to observe broken strands, oxidation, and corrosion, facilitating inspection and maintenance. Overhead lines rely on air as the insulating medium and insulators to isolate the live conductors from the towers, achieving electrical insulation. Sufficient phase-to-phase and phase-to-ground distances must be maintained during installation to ensure safety.

[0003] Therefore, the weight of the overhead line itself plays a crucial role in the safety of the line and the theoretical design of the tower. The current mainstream approach is based on conductors with circular cross-sections. By optimizing the material of the conductor, the weight can be reduced, for example, by using aluminum alloy with high conductivity. However, due to limitations in material development, it is difficult to find a better optimization scheme to reduce the weight of overhead lines. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a lightweight overhead line for high-altitude use. The cross-section of the line is optimized into a low-speed airfoil. When used overhead, the Bernoulli effect is used to generate lift to offset part of the overhead line's own weight, thereby enhancing the safety of the line.

[0005] The technical solution to achieve the objective of this invention is:

[0006] A lightweight overhead power line for high-altitude use includes a conductor made of a highly conductive aluminum alloy, the conductor having a low-speed airfoil cross-section.

[0007] Furthermore, the conductor includes a first conductor unit, a second conductor unit, and a locking part. The first conductor unit and the second conductor unit extend along the axial direction of the conductor and are fixed by the locking part along the cross-sectional length direction of the conductor.

[0008] Furthermore, the locking part is provided in at least two sets, distributed along the thickness direction of the conductor cross section and close to the outer surface of the conductor.

[0009] Further, the first wire unit and the second wire unit are provided with a clamping groove on any one of the bonding surfaces, and a clamping buckle matched with the clamping groove is arranged on the other bonding surface, and the clamping groove and the clamping buckle form the locking part.

[0010] Further, the center of the conductor is provided with a reinforcing core.

[0011] Further, the reinforcing core is a carbon fiber core.

[0012] Further, the carbon fiber core has an elongated structure extending along the length direction of the cross section of the conductor.

[0013] Further, the carbon fiber core is wrapped with a protective layer made of nylon.

[0014] Further, a monitoring optical fiber is implanted in the carbon fiber core.

[0015] By adopting the above technical scheme, the present application has the following beneficial effects:

[0016] (1) The present application breaks the traditional thinking and optimizes the material of the conductor to reduce the self weight, innovatively optimizes the cross section of the conventional conductor from a circular shape to a low-speed airfoil shape, combines the existing high-conductivity aluminum alloy material, and realizes the use of the conductor in the air, utilizes the Bernoulli effect to generate lift to offset part of the self weight of the overhead line, thereby enhancing the safety of the line; at the same time, the cross section structure of the low-speed airfoil shape increases the surface area of the conductor, which is more conducive to heat dissipation of the conductor, thereby increasing the carrying capacity of the line and reducing the power loss of the long-distance power transmission line.

[0017] (2) The present application innovatively adopts a two-half structure design for the conductor, and assembles the whole through the locking part, solves the problem that the low-speed airfoil cross section conductor cannot be produced by the traditional method of twisting multiple circular conductors, and realizes the large cross section conductor.

[0018] (3) The present application sets the locking part near the outer surface of the conductor, and at least two groups are arranged along the thickness direction of the conductor, thereby ensuring the stability of the overall structure of the assembled conductor.

[0019] (4) The present application realizes the fixed assembly of the first wire unit and the second wire unit by the clamping buckle and the clamping groove, has a simple structure, is convenient to assemble, cannot be separated after assembly, and ensures the safety of the line.

[0020] (5) The present application adds a carbon fiber core as a reinforcing core in the conductor, improves the overall tensile strength, and at the same time, reduces the self weight of the conductor as much as possible, and at the same time, sets the cross section as an elongated type, thereby considering the cross section size of the reinforcing core, the installation difficulty and the distribution position in the conductor, and realizing the optimal tensile effect.

[0021] (6) The present invention adds a protective layer of nylon material to the surface of the carbon fiber core, which has strong wear resistance and the nylon surface is smooth, which is conducive to the installation of the split conductor and avoids scratching the surface of the carbon fiber core and causing breakage.

[0022] (7) By adding a monitoring optical fiber inside the carbon fiber core, when the carbon fiber core breaks, the monitoring optical fiber will inevitably break, thereby monitoring the internal state of the carbon fiber core at all times, ensuring the safe and stable operation of the line, and improving the safety of use. Attached Figure Description

[0023] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0024] Figure 1 This is a schematic diagram of the structure of the present invention.

[0025] The labels in the attached diagram are:

[0026] First conductor unit 1, second conductor unit 2, slot 3, buckle 4, reinforcing core 5, protective layer 6, optical fiber 7. Detailed Implementation

[0027] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0028] Example 1, such as Figure 1 The lightweight overhead power line shown includes a conductor made of highly conductive aluminum alloy with a low-speed airfoil cross-section. By optimizing the conductor's structure, the weight is reduced. Breaking with traditional thinking, the conventional conductor cross-section is innovatively optimized from a circle to a low-speed airfoil. Combined with existing high-conductivity aluminum alloy materials, when the conductor is used overhead, the Bernoulli effect is used to generate lift to offset part of the overhead line's own weight, thereby enhancing the line's safety. At the same time, the low-speed airfoil cross-section structure increases the conductor's surface area, which is more conducive to heat dissipation, thereby increasing the line's current carrying capacity and reducing power loss in long-distance transmission lines.

[0029] Specifically, the low-speed airfoil refers to the wing profile shape with excellent aerodynamic performance under low-speed flight conditions. Common low-speed airfoils include NACA four-digit airfoils, NACA five-digit airfoils, NACA laminar airfoils, etc. The present embodiment adopts a NACA four-digit airfoil, which has a round blunt leading edge to help maintain airflow attachment at high angles of attack. The trailing edge is sharp, allowing the airflow on the upper and lower surfaces to smoothly converge. The straight line connecting the leading edge and the trailing edge, i.e., the chord length, is 50-150 mm. The maximum thickness is 8-16% of the chord length, and the maximum camber is 1-4%. The maximum camber refers to the maximum curvature of the camber line relative to the chord line. The camber line is a curve connecting the midpoints of the upper and lower surfaces of the airfoil at each chordwise position. The upper surface is convex upward, creating a low-pressure area and providing primary lift. The lower surface is relatively flat and slightly curved downward. For conductors with small nominal cross-sectional areas (e.g., 100 mm² to 240 mm²), the thickness-to-chord ratio of the airfoil is preferably designed to be 14-16%, and the maximum camber is preferably 2.5-3%. For conductors with medium nominal cross-sectional areas (e.g., 300 mm² to 630 mm²), the thickness-to-chord ratio of the airfoil is preferably designed to be 12-14%, and the maximum camber is preferably 2-2.5%. For conductors with large nominal cross-sectional areas (e.g., 800 mm² to 2000 mm²), the thickness-to-chord ratio of the airfoil is preferably designed to be 8-12%, and the maximum camber is preferably 1-2%. By designing the appropriate low-speed airfoil shape for conductors of different cross-sectional areas, optimal results can be achieved.

[0030] Due to the need for a large flatness ratio in the cross-section of the low-speed airfoil, the traditional round aluminum wire twisting structure is completely unsuitable. Therefore, the present embodiment innovatively designs the conductor in a two-piece structure. Specifically, the conductor includes a first wire unit 1, a second wire unit 2, and a locking portion. The first wire unit 1 and the second wire unit 2 both extend along the axial direction of the conductor and are fixed along the cross-sectional length direction of the conductor by the locking portion. The locking portion is provided with two groups of locking portions distributed along the thickness direction of the conductor and close to the outer surface of the conductor. The mating surfaces of the first wire unit 1 and the second wire unit 2 are provided with a clamping groove 3, and the other mating surface is provided with a clamping buckle 4 corresponding to the clamping groove 3. The two groups of clamping buckles 4 are respectively clamped into the corresponding clamping grooves 3, forming two groups of locking portions, which is simple in structure. First, a mold corresponding to the shape of the two-piece airfoil conductor is used to extrude the corresponding wire units. Then, the wire units are assembled by clamping, which is convenient to assemble and cannot be disassembled after assembly, ensuring the safety of the line.

[0031] In order to improve the tensile strength of the conductor, the embodiment is provided with a reinforcing core 5 in the center of the conductor. In order to balance the tensile strength and the weight of the conductor, the embodiment preferably uses a carbon fiber core as the reinforcing core 5, which has a large breaking force and a light weight. Limited by the cross-sectional shape of the conductor, the traditional circular cross-sectional reinforcing core cannot be used. The cross-section of the carbon fiber core is designed into an elongated rectangular structure extending along the length direction of the cross-section of the conductor, so as to balance the cross-sectional size of the reinforcing core 5, the installation difficulty and the distribution position in the conductor, and achieve the optimal tensile effect.

[0032] Although the carbon fiber material belongs to a high tensile material, the split type conductor is easy to scratch the surface of the carbon fiber during assembly, causing the fracture of the carbon fiber. Therefore, the embodiment extrudes a layer of nylon material on the surface of the carbon fiber core to form a protective layer 6. The nylon has a strong wear resistance and a smooth surface, which is beneficial to the assembly of the split type conductor.

[0033] In order to prevent the internal damage of the carbon fiber core during processing, transportation, assembly and operation, and thus cause the fracture and cause the safety hazard of the overhead line, the embodiment implants an optical fiber 7 in the carbon fiber core. The fracture of the carbon fiber core will inevitably cause the fracture of the optical fiber 7, so as to monitor the internal state of the carbon fiber at any time and ensure the safe and stable operation of the line.

[0034] The cable of the embodiment is subjected to wind tunnel lift test, and the results are shown in Table 1.

[0035] Table 1

[0036] The application breaks the inherent traditional thinking, optimizes the material of the conductor to reduce the weight, innovatively optimizes the cross-section of the conventional conductor from a circular shape to a low-speed wing shape, combines the existing high-conductive aluminum alloy material, realizes the use of the overhead conductor, uses the Bernoulli effect to generate lift to offset part of the self-gravity of the overhead line, and thus enhances the safety of the line. At the same time, the cross-sectional structure of the low-speed wing type increases the surface area of the conductor, which is more conducive to the heat dissipation of the conductor, thereby increasing the carrying capacity of the line and reducing the power loss of the long-distance power transmission line.

[0037] The above-described specific embodiments further illustrate the purpose, technical solutions and advantages of the application. It should be understood that the above-described specific embodiments are only examples of the application and are not used to limit the application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the application should be included in the protection scope of the application.

Claims

1. A lightweight overhead power line for high-altitude applications, characterized in that: The conductor is made of a high-conductivity aluminum alloy. The cross-section of the conductor is a low-speed airfoil with a chord length of 50-150 mm, a maximum thickness of 8-16% of the chord length, and a maximum curvature of 1-4%. The conductor includes a first conductor unit, a second conductor unit, and a locking part. The first and second conductor units extend along the axial direction of the conductor and are fixed by the locking part along the cross-sectional length of the conductor. The mating surfaces of the first and second conductor units are symmetrically provided with grooves to form a rectangular groove with a slender cross-section. The rectangular groove is filled with a reinforcing core.

2. The lightweight overhead power line for high-altitude use according to claim 1, characterized in that: The locking part is provided in at least two sets, distributed along the thickness direction of the conductor cross section and close to the outer surface of the conductor.

3. A lightweight overhead power line for high-altitude use according to claim 2, characterized in that: A slot is provided on either the first wire unit or the second wire unit, and a buckle adapted to the slot is provided on the other contact surface. The slot and the buckle form the locking part.

4. A lightweight overhead power line for high-altitude use according to claim 1, characterized in that: The reinforcing core is a carbon fiber core.

5. A lightweight overhead power line for high-altitude use according to claim 4, characterized in that: The carbon fiber core is wrapped with a protective layer made of nylon.

6. A lightweight overhead power line for high-altitude use according to claim 5, characterized in that: The carbon fiber core is embedded with a monitoring optical fiber.

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