High-conductivity steel-cored aluminum stranded conductor overhead insulated power cable

Abstract

The utility model relates to the technical field of wires and cables, in particular to a high-conductivity steel-cored aluminum stranded conductor overhead insulated power cable, which comprises a conductor, a conductor shielding layer and an insulating layer which are distributed from inside to outside, and is characterized in that the conductor comprises a steel core structure and a plurality of metal wire bundles stranded outside the steel core structure; the plurality of metal wire bundles are attached to each other in the cross section of the cable to form an annular structure. According to the utility model, the conductor adopts the steel strand as the core, and the aluminum alloy wires and the thin copper wires are twisted on the outer layer of the core by the metal wire bundle wrapped by the copper strip to form the conductor with the circular cross section, so that the conductor structure can improve the conductivity of the lead, and the lead is enabled to be light while the lead is maintained; moreover, the combination of the aluminum alloy wires and the fine copper wires enables the conductor to have higher conductivity, and compared with a compressed molded line aluminum alloy conductor, the conductor structure has higher tensile strength and wind pressure resistance, and also has better bending resistance and vibration resistance.

Description

Technical Field

[0001] This utility model relates to the field of wire and cable technology, and more specifically to a high conductivity steel-cored aluminum stranded overhead insulated power cable. Background Technology

[0002] Overhead aluminum conductors are mainly used in power system transmission lines, especially medium and low voltage transmission lines. They are erected on poles or supports to form overhead transmission lines, transmitting electrical energy from power plants or substations to users. With the rapid development of the power industry and the widespread application of new energy sources, the performance and quality requirements for overhead aluminum conductors are constantly increasing.

[0003] The conductor of a steel-cored aluminum stranded overhead cable mainly consists of a steel core and aluminum strands. The steel core, located in the center, provides the cable with mechanical strength and tensile strength; the aluminum strands are stranded around the steel core and serve as the main conductive part. To protect the conductor and prevent current leakage, a layer of insulation is usually wrapped around the conductor in steel-cored aluminum stranded overhead cables. This insulation layer is typically made of cross-linked polyethylene (XLPE) or other high-performance insulating materials, possessing excellent electrical properties and weather resistance.

[0004] Currently, there are generally three methods to improve the conductivity of conductors. The first is to use aluminum alloy wire with higher conductivity, such as the L3 type round aluminum conductor with a conductivity of 62.5% IACS. The second is to use irregularly shaped stranded wires. The third is to use thinner aluminum stranded wires to increase the current carrying area. However, the first method has a limited upper limit on conductivity, the second method increases the stiffness and hardness of the cable, making installation and laying difficult, and the third method reduces tensile strength and may even cause wire breakage. Therefore, how to improve the conductivity of aluminum stranded overhead cables is an urgent problem to be solved. Utility Model Content

[0005] In view of the technical problems existing in the existing overhead insulated cables, the first aspect of this utility model proposes a high conductivity steel core aluminum stranded overhead insulated power cable, which includes a conductor, a conductor shielding layer and an insulation layer distributed from the inside to the outside. The conductor includes a steel core structure and multiple metal wire bundles stranded on the outside of the steel core structure. The multiple metal wire bundles are attached to each other in the cross-section of the cable to form a ring structure.

[0006] Each bundle of metal wires includes multiple aluminum alloy wires and fine copper wires disposed in the gaps between the aluminum alloy wires. The aluminum alloy wires and the fine copper wires are wrapped together by copper strips to form a bundle of metal wires with a predetermined cross-sectional shape.

[0007] As an optional implementation, the steel core structure includes 7 steel wires, the steel wires and aluminum alloy wires having the same diameter, and the 7 steel wires are twisted together in a regular 1+6 twisted structure.

[0008] As an optional implementation, the copper strip is wrapped to the left with an overlap rate of 15% to 30%.

[0009] As an optional implementation, the thickness of the copper strip is less than or equal to 0.2 mm.

[0010] As an optional implementation, the plurality of metal wire bundles are divided into two types, namely a first metal wire bundle and a second metal wire bundle, wherein the cross-sectional shape of the first metal wire bundle is fan-shaped and the cross-sectional shape of the second metal wire bundle is elliptical.

[0011] As an optional implementation, the first metal wire bundle has three layers of aluminum alloy wires arranged from the inside out. The first layer includes one aluminum alloy wire, the second layer includes two aluminum alloy wires, and the third layer includes three aluminum alloy wires.

[0012] The second metal wire bundle has three layers of aluminum alloy wires arranged from the inside out, and each layer includes one aluminum alloy wire.

[0013] The fine copper wire is filled in the gap between the aluminum alloy wire and the copper strip.

[0014] As an optional implementation, the aluminum alloy wire is an L3 type circular aluminum conductor with a conductivity of 62.5% IACS.

[0015] As an optional implementation, the conductor shielding layer includes a semiconductive shielding layer extruded outside the conductor.

[0016] As an optional implementation, the insulating layer includes a cross-linked polyethylene insulating layer extruded outside the conductor shielding layer.

[0017] Compared with the prior art, the advantages of this utility model are:

[0018] The conductor of this invention uses steel strand as the core, with aluminum alloy wire and fine copper wire wrapped in copper strip and twisted together on the outer layer of the core to form a conductor with a circular cross-section. This conductor structure can improve the conductivity of the wire, making the wire lightweight. The combination of aluminum alloy wire and fine copper wire gives the conductor higher conductivity. Compared with compacted aluminum alloy conductors, this conductor structure has higher tensile strength and wind pressure resistance, as well as better bending and vibration resistance. Attached Figure Description

[0019] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings, wherein:

[0020] Figure 1 This is a schematic diagram of the structure of the high conductivity steel-cored aluminum stranded overhead insulated power cable shown in this utility model.

[0021] Figure 2 This is a schematic diagram of the cross-sectional structure of the high conductivity steel-cored aluminum stranded overhead insulated power cable shown in this utility model. Detailed Implementation

[0022] To better understand the technical content of this utility model, specific embodiments are provided below in conjunction with the accompanying drawings.

[0023] Combination Figure 1 As shown, the first aspect of this utility model proposes a high conductivity steel-cored aluminum stranded overhead insulated power cable, including a conductor, a conductor shielding layer 3 and an insulation layer 4 distributed from the inside out. The conductor includes a steel core structure 1 and multiple metal wire bundles 2 stranded on the outside of the steel core structure 1. The multiple metal wire bundles 2 are attached to each other in the cross-section of the cable to form a ring structure.

[0024] Each bundle of metal wires 2 includes multiple aluminum alloy wires 21 and fine copper wires 22 disposed in the gaps of the aluminum alloy wires 21. The aluminum alloy wires 21 and the fine copper wires 22 are wrapped together by copper strip 23 to form a bundle of metal wires 2 with a predetermined cross-sectional shape.

[0025] Thus, aluminum alloy wire 21 and fine copper wire 22 are wrapped with copper strip 23 to form a metal wire bundle. This metal wire bundle can be made into a predetermined shape. Under the same diameter, it is beneficial to splice the conductors to form a structure with a larger current carrying area. At the same time, the tensile strength of the fine copper wire is better than that of the aluminum alloy wire. When the overhead cable is erected and swings under the action of temperature difference and airflow, the integrity of the conductor can be guaranteed and no wire breakage will occur.

[0026] In addition, the combination of aluminum alloy wire and copper wire can further improve the conductivity of the wire, so that the wire can have higher conductivity while maintaining its lightweight nature.

[0027] Optionally, the steel core structure 1 includes 7 steel wires, the steel wires and aluminum alloy wires 21 have the same diameter, and the 7 steel wires are twisted together in a regular 1+6 twisted structure.

[0028] Thus, the use of steel-core stranded wire significantly enhances the conductor's tensile strength and wind pressure resistance, enabling it to maintain stable transmission performance even under harsh weather conditions. Furthermore, the outer layer's multi-bundle irregularly shaped aluminum stranded wire structure also increases the conductor's overall mechanical strength, improving its resistance to bending and vibration.

[0029] In optional embodiments, such as Figure 2As shown, the multiple metal wire bundles 2 are divided into two types: a first metal wire bundle 201 and a second metal wire bundle 202. The first metal wire bundle 201 has a fan-shaped cross-section, and the second metal wire bundle 202 has an elliptical cross-section. In this way, these two types of metal wire bundles 2 can be spliced ​​together on the outside of the steel core structure 1 to form a tight ring conductor structure.

[0030] Furthermore, the copper strip 23 is wrapped to the left with an overlap rate of 15% to 30%. The thickness of the copper strip 23 is less than or equal to 0.2 mm. In this way, the aluminum alloy wire and fine copper wire are constrained by the thin copper strip, forming a bundle of multiple wires. These bundles are then twisted together. This twisting structure reduces the gaps between conductors, lowers contact resistance, and reduces current loss during transmission, thereby improving conductivity. The wrapping of the copper strip not only provides additional shielding but also increases the conductive area of ​​the wire to a certain extent, further improving conductivity.

[0031] In an optional embodiment, the first metal wire bundle 201 is provided with three layers of aluminum alloy wires 21 arranged from the inside out. The first layer includes one aluminum alloy wire 21, the second layer includes two aluminum alloy wires 21, and the third layer includes three aluminum alloy wires 21.

[0032] The second metal wire bundle 202 is provided with three layers of aluminum alloy wires 21 arranged from the inside to the outside, and each layer includes one aluminum alloy wire 21.

[0033] The fine copper wire 22 fills the gap between the aluminum alloy wire 21 and the copper strip 23.

[0034] Compared to stranded aluminum alloy cables, this type of conductor has better flexibility and adaptability, enabling it to cope with various complex terrains and climatic conditions, ensuring the stability and reliability of power transmission.

[0035] In the above embodiments, the aluminum alloy wire 21 is an L3 type circular aluminum conductor with a conductivity of 62.5% IACS.

[0036] Furthermore, the conductor shielding layer 3 includes a semiconducting shielding layer extruded outside the conductor, and the insulation layer 4 includes a cross-linked polyethylene insulation layer extruded outside the conductor shielding layer 3.

[0037] In conjunction with the above embodiments, the conductor of this utility model uses steel stranded wire as the core, and aluminum alloy wire and fine copper wire are twisted together in a metal wire bundle wrapped with copper strip on the outer layer of the core to form a conductor with a circular cross-section. This conductor structure can improve the conductivity of the wire, so that the wire remains lightweight. Moreover, the combination of aluminum alloy wire and fine copper wire makes the conductor have higher conductivity. Compared with compacted aluminum alloy conductors, this conductor structure has higher tensile strength and wind pressure resistance, as well as better bending resistance and vibration resistance.

[0038] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Those skilled in the art to which this invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of this invention shall be determined by the claims.

Claims

1. An overhead insulated power cable of the type comprising a high-conductivity steel-cored aluminium strand, characterized in that, The conductor includes a steel core structure (1) and a plurality of wire bundles (2) twisted outside the steel core structure (1), and the plurality of wire bundles (2) are mutually adhered to form a ring structure in the cross section of the cable. Each wire bundle (2) includes a plurality of aluminum alloy wires (21) and a fine copper wire (22) arranged in the gap of the aluminum alloy wires (21), and the aluminum alloy wires (21) and the fine copper wire (22) are wrapped together by a copper tape (23) to form a wire bundle (2) with a predetermined cross-sectional shape. The wire bundles (2) are divided into two types, namely first wire bundles (201) and second wire bundles (202), the cross-sectional shape of the first wire bundles (201) is fan-shaped, and the cross-sectional shape of the second wire bundles (202) is elliptical.

2. The high conductivity steel-cored aluminium-stripped overhead insulated electric power cable according to claim 1, characterized in that, The steel core structure (1) includes seven steel wires, the diameters of the steel wires and the aluminum alloy wires (21) are the same, and the seven steel wires are twisted according to a regular 1+6 twisting structure.

3. The high conductivity steel-cored aluminium-stripped overhead insulated electric power cable according to claim 1, characterized in that, The copper tape (23) is wrapped leftward according to a lap rate of 15% to 30%.

4. The high conductivity steel-cored aluminum conductor (ACAA) overhead insulated power cable according to claim 1, characterized in that, The thickness of the copper tape (23) is less than or equal to 0.2 mm.

5. The high conductivity steel-cored aluminum conductor (ACAA) overhead insulated power cable according to claim 1, wherein, The first wire bundle (201) is provided with three layers of aluminum alloy wires (21) arranged from inside to outside, the first layer includes one aluminum alloy wire (21), the second layer includes two aluminum alloy wires (21), and the third layer includes three aluminum alloy wires (21). The second wire bundle (202) is provided with three layers of aluminum alloy wires (21) arranged from inside to outside, each layer includes one aluminum alloy wire (21).

6. The high conductivity steel-cored aluminum conductor (ACAA) overhead insulated power cable according to claim 1, wherein, The fine copper wire (22) is filled in the gap between the aluminum alloy wires (21) and the copper tape (23).

7. The high conductivity steel-cored aluminum conductor (ACAA) overhead insulated power cable according to claim 1, characterized in that, The aluminum alloy wire (21) adopts an L3 type circular aluminum conductor with an electrical conductivity of 62.5% IACS.

8. The high conductivity steel-cored aluminum conductor (ACAA) overhead insulated power cable according to claim 1, wherein, The conductor shielding layer (3) includes a semi-conductive shielding layer extruded outside the conductor.

9. The high conductivity steel-cored aluminum conductor (ACAA) overhead insulated power cable according to claim 1, wherein, The insulation layer (4) includes a cross-linked polyethylene insulation layer extruded outside the conductor shielding layer (3).

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