High-performance large-short-circuit-current-capacity OPGW optical cable

Abstract

The utility model discloses a high-performance large-short-circuit-current-capacity OPGW optical cable which comprises a central strand, an optical fiber unit, an aluminum alloy wire II, a second stranded wire layer and a third stranded wire layer. The four aluminum alloy wires II and the two optical fiber units are concentrically stranded on the outer surface of the central strand at equal intervals, and the two optical fiber units and the four aluminum alloy wires II are symmetrically arranged on the cross section of the first stranded wire layer in the circumferential direction of the first stranded wire layer to form the first stranded wire layer; the second stranded wire layer is coaxially stranded on the outer surface of the first stranded wire layer, the third stranded wire layer is coaxially stranded on the outer surface of the second stranded wire layer, and the second stranded wire layer and the third stranded wire layer adopt a layer-stranded symmetrical irregular stranding design with small inside and large outside, so that the electrical performance and the lightning stroke resistance performance are ensured. According to the utility model, an irregular stranding design with small inside and large outside is adopted, so that the electrical performance and the lightning stroke resistance are ensured, higher instantaneous short-circuit current can be borne, and the safety and the stability are improved.

Description

Technical Field

[0001] The utility model relates to the field of communication technologies, and particularly relates to a high-performance OPGW optical cable with a large short-circuit current capacity. Background Art

[0002] With the continuous growth of power demand, the transmission capacity of the power system is also increasing continuously. The safety and stability of the power grid are crucial for the normal operation of the power system, especially in high-voltage power grids (such as transmission lines with voltage levels of 500 kV, 220 kV, etc.). These high-voltage power grids have higher requirements for the short-circuit current capacity of optical cables to ensure that the optical cables can withstand the impact of large currents without damage during short-circuit faults. The application of OPGW optical cables with a large short-circuit current capacity can improve the fault tolerance of the power grid and reduce the risk of power grid damage and power outages caused by short-circuit faults.

[0003] When the outer diameter of the OPGW remains unchanged, the space for improving the short-circuit current capacity of the OPGW with a multi-layer high-conductivity aluminum-clad steel wire stranding type or an aluminum tube cable core stranding type is limited. Especially when the short-circuit current capacity requirement of the line exceeds 650 kA²s, the above two structures cannot meet the requirements.

[0004] Currently, the main method for improving the short-circuit current capacity is to enlarge the structure, that is, to adopt the design concept of multi-layer single-wire stranding. However, when the cross-sectional area or diameter of the OPGW optical cable increases, the load on the line towers increases, and the line towers need to be re-reinforced or redesigned, resulting in a significant increase in the construction cost of the line.

[0005] Chinese Patent with application number 201620242757.6 discloses "a high-strength lightweight optical fiber composite overhead ground wire", which achieves the purpose of increasing the short-circuit capacity, but still cannot meet the short-circuit capacity technical index of 650 kA²s and above.

[0006] Chinese Patent with application number 201520196359.0 discloses "a large cross-section optical fiber composite overhead ground wire", but it is a full-steel type design, and the overall weight is relatively large, which increases the load-bearing burden on the towers and may require the towers to have higher structural strength and stability, and is not suitable for the transformation of old lines.

[0007] Therefore, the above problems need to be solved urgently. Summary of the Invention

[0008] The technical problem to be solved by the utility model is to provide a high-performance OPGW optical cable with a large short-circuit current capacity. On the basis of not increasing the outer diameter of the OPGW optical cable and the line construction cost, the OPGW structure is optimized, and a non-regular stranding design with a small inner part and a large outer part is adopted, which not only ensures the electrical performance and lightning resistance performance, but also can withstand a higher instantaneous short-circuit current, reduces the fault risk caused by short circuits, and thus improves the safety and stability of the power system.

[0009] To solve the above technical problems, the present utility model adopts the following technical solutions: A high-performance OPGW optical cable with a large short-circuit current capacity of the present utility model is characterized in that it includes a central strand, an optical fiber unit, an aluminum alloy wire II, a second stranded layer, and a third stranded layer; four aluminum alloy wires II and two optical fiber units are concentrically stranded at equal intervals on the outer surface of the central strand, and the two optical fiber units and the four aluminum alloy wires II are symmetrically arranged along the circumferential direction of the cross-section of the first stranded layer and form the first stranded layer; the second stranded layer is concentrically stranded on the outer surface of the first stranded layer, and the third stranded layer is concentrically stranded on the outer surface of the second stranded layer. The second stranded layer and the third stranded layer adopt an internal-small-external-large layer-stranded symmetric non-regular stranding design, thereby ensuring electrical performance and lightning resistance performance.

[0010] Preferably, the central strand is made of aluminum alloy wire I, and its outer diameter is 3.7 mm.

[0011] Preferably, each optical fiber unit includes an optical fiber, an optical fiber sleeve, and optical fiber ointment; an optical fiber is sleeved in each optical fiber sleeve, and optical fiber ointment is evenly filled in the whole circumference between each optical fiber sleeve and the corresponding optical fiber.

[0012] Preferably, each optical fiber sleeve is made of a stainless steel tube, and its outer diameter is 3.5 mm.

[0013] Preferably, the number of cores of each optical fiber is not less than 144 cores.

[0014] Preferably, the second stranded layer is composed of several aluminum alloy wires III stranded concentrically at equal intervals, and the outer diameter of each aluminum alloy wire III is 2.5 mm.

[0015] Preferably, the third stranded layer is composed of four aluminum alloy wires IV and several aluminum-clad steel wires stranded concentrically at equal intervals, and the four aluminum alloy wires IV and the several aluminum-clad steel wires are symmetrically arranged along the circumferential direction of the cross-section of the first stranded layer; the outer diameter of each aluminum alloy wire IV and each aluminum-clad steel wire is 3.2 mm, and the model of each aluminum-clad steel wire can be selected as 14% IACS, 20.3% IACS, or 27% IACS according to the actual line design requirements.

[0016] Preferably, the aluminum alloy wire I, the four aluminum alloy wires II, each aluminum alloy wire III, and the four aluminum alloy wires IV all adopt a closely arranged high-density aluminum alloy wire, and their models are selected as LHA1 type or LHA2 type.

[0017] The beneficial effects of the present utility model:

[0018] (1)On the basis of not increasing the outer diameter of the OPGW optical cable and the line construction cost, the present utility model optimizes the OPGW structure and adopts a non-regular stranding design with a smaller inner diameter and a larger outer diameter, which not only ensures the electrical performance and lightning resistance performance, but also can withstand a higher instantaneous short-circuit current, reduces the fault risk caused by short circuits, and thus improves the safety and stability of the power system;

[0019] (2)The present utility model adopts a closely arranged high-density aluminum alloy wire design. Due to its high strength and high toughness, it can achieve a larger current-carrying cross-sectional area while ensuring the mechanical strength of the OPGW optical cable, thereby increasing the short-circuit current capacity;

[0020] (3)In the third stranding layer of the present utility model, part of the aluminum alloy wire Ⅳ is stranded with the aluminum-clad steel wire, which not only optimizes the electrical performance of the OPGW optical cable, but also helps to achieve overall lightweighting, enabling the OPGW optical cable to reduce unnecessary material use while maintaining sufficient strength and stability, thereby reducing the overall weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a schematic structural diagram of a high-performance OPGW optical cable with a large short-circuit current capacity of the present utility model.

[0023] Figure 2 For Figure 1 the schematic structural diagram of the optical fiber unit in

[0024] Among them, 1 - central strand; 2 - aluminum alloy wire Ⅱ; 3 - optical fiber unit; 31 - optical fiber; 32 - optical fiber sleeve; 33 - optical fiber ointment; 4 - aluminum alloy wire Ⅲ; 5 - aluminum alloy wire Ⅳ; 6 - aluminum-clad steel wire. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The technical solutions of the present utility model will be clearly and completely described below through specific embodiments.

[0026] A high-performance OPGW optical cable with a large short-circuit current capacity of the present utility model includes a central strand 1, an optical fiber unit 3, an aluminum alloy wire Ⅱ 2, a second stranding layer and a third stranding layer; the specific structure is as Figure 1 、 Figure 2As shown, the central strand 1 is made of aluminum alloy wire I with an outer diameter of 3.7 mm; four aluminum alloy wires II 2 and two optical fiber units 3 are concentrically stranded at equal intervals on the outer surface of the central strand 1, and the two optical fiber units 3 and the four aluminum alloy wires II 2 are symmetrically arranged along the circumferential direction of the cross-section of the first stranded layer, forming the first stranded layer.

[0027] Each optical fiber unit 3 of the present utility model includes an optical fiber 31, an optical fiber sleeve 32 and optical fiber ointment 33; as Figure 1 、 Figure 2 shown, an optical fiber 31 is sleeved in each optical fiber sleeve 32, and optical fiber ointment 33 is uniformly filled in the whole circumference between each optical fiber sleeve 32 and the corresponding optical fiber 31; wherein, each optical fiber sleeve 32 is made of a stainless steel tube with an outer diameter of 3.5 mm; the number of cores of each optical fiber 31 is not less than 144 cores. By setting the optical fiber ointment 33, the present utility model can reduce the damage to the optical fiber 31 caused by moisture intrusion or friction on the optical fiber 31, ensuring the mechanical properties of the optical fiber 31; at the same time, by setting the optical fiber sleeve 32, the optical fiber 31 can be further protected, extending its service life.

[0028] The second stranded layer of the present utility model is concentrically stranded on the outer surface of the first stranded layer, and the third stranded layer is concentrically stranded on the outer surface of the second stranded layer. The second stranded layer and the third stranded layer adopt an inner-small and outer-large layer-stranded symmetric non-regular stranding design, thereby ensuring electrical performance and lightning resistance; as Figure 1 、 Figure 2 shown, the second stranded layer is composed of several aluminum alloy wires III 4 stranded concentrically at equal intervals, and the outer diameter of each aluminum alloy wire III 4 is 2.5 mm.

[0029] As Figure 1 、 Figure 2 shown, the third stranded layer is composed of four aluminum alloy wires IV 5 and several aluminum clad steel wires 6 stranded concentrically at equal intervals, and the four aluminum alloy wires IV 5 and the several aluminum clad steel wires 6 are symmetrically arranged along the circumferential direction of the cross-section of the first stranded layer; the outer diameter of each aluminum alloy wire IV 5 and each aluminum clad steel wire 6 is 3.2 mm, and the type of each aluminum clad steel wire 6 can be selected as 14% IACS, 20.3% IACS or 27% IACS according to the actual line design requirements.

[0030] As Figure 1 、 Figure 2 shown, the aluminum alloy wire I, the four aluminum alloy wires II 2, each aluminum alloy wire III 4 and the four aluminum alloy wires IV 5 all adopt closely arranged high-density aluminum alloy wires, and their types are selected as LHA1 type or LHA2 type.

[0031] The utility model adopts a non-regular stranding design with a smaller inner part and a larger outer part, which ensures the electrical performance and lightning resistance performance. Specifically: 1) As a composite overhead ground wire, OPGW needs to have good electrical performance; the stranding design with a smaller inner part and a larger outer part not only ensures the mechanical performance of the optical cable but also retains its original electrical characteristics, such as good electrical conductivity and corrosion resistance. This enables OPGW to effectively play the role of lightning protection in the transmission line; 2) The larger outer third stranding layer can improve the lightning resistance level of the line. When lightning strikes the transmission line, it can guide the lightning current to quickly discharge into the ground through the ground wire, protecting the safety of the transmission line and communication equipment.

[0032] The beneficial effects of the utility model are as follows:

[0033] (1) On the basis of not increasing the outer diameter of the OPGW optical cable and the line construction cost, the utility model optimizes the OPGW structure and adopts a non-regular stranding design with a smaller inner part and a larger outer part. It not only ensures the electrical performance and lightning resistance performance but also can withstand a higher instantaneous short-circuit current, reducing the fault risk caused by short circuits, thereby improving the safety and stability of the power system;

[0034] (2) The utility model adopts a close-packed high-density aluminum alloy wire design. Due to its high strength and high toughness, it can achieve a larger current-carrying cross-sectional area while ensuring the mechanical strength of the OPGW optical cable, thereby increasing the short-circuit current capacity;

[0035] (3) The third stranding layer of the utility model is stranded with part of aluminum alloy wire Ⅳ5 and aluminum-clad steel wire 6, which not only optimizes the electrical performance of the OPGW optical cable but also helps to achieve overall light weight. While maintaining sufficient strength and stability, the OPGW optical cable reduces unnecessary material use, thereby reducing the overall weight.

[0036] The above-described embodiments are only described as the preferred embodiments of the utility model, and do not limit the concept and scope of the utility model. Without departing from the design concept of the utility model, various variations and improvements made by ordinary engineering and technical personnel in the field to the technical solution of the utility model should fall within the protection scope of the utility model. The technical content claimed by the utility model has been fully recorded in the technical requirements.

Claims

1. A high-performance OPGW optical cable with a large short-circuit current capacity, characterized in that: It includes a central strand, an optical fiber unit, aluminum alloy wire II, a second stranded layer, and a third stranded layer; four aluminum alloy wires II and two optical fiber units are concentrically stranded at equal intervals on the outer surface of the central strand, and the two optical fiber units and the four aluminum alloy wires II are symmetrically arranged along the circumference on the cross-section of the first stranded layer, and form the first stranded layer; the second stranded layer is concentrically stranded on the outer surface of the first stranded layer, and the third stranded layer is concentrically stranded on the outer surface of the second stranded layer. The second stranded layer and the third stranded layer adopt an inner-small and outer-large layer-stranded symmetric non-regular stranding design, thereby ensuring electrical performance and lightning resistance performance.

2. The high-performance OPGW optical cable with a large short-circuit current capacity according to claim 1, characterized in that: The central strand is made of aluminum alloy wire I, and its outer diameter is 3.7 mm.

3. A high-performance OPGW optical cable with a large short-circuit current capacity according to claim 1, characterized in that: Each optical fiber unit includes an optical fiber, an optical fiber sleeve, and optical fiber ointment; an optical fiber is sleeved in each optical fiber sleeve, and optical fiber ointment is uniformly filled in the whole circumference between each optical fiber sleeve and the corresponding optical fiber.

4. A high-performance OPGW optical cable with a large short-circuit current capacity according to claim 3, characterized in that: Each optical fiber sleeve is made of a stainless steel tube, and its outer diameter is 3.5 mm.

5. A high-performance OPGW optical cable with a large short-circuit current capacity according to claim 3, characterized in that: The core number of each optical fiber should be not less than 144 cores.

6. A high-performance OPGW optical cable with a large short-circuit current capacity according to claim 2, characterized in that: The second stranded layer is composed of several aluminum alloy wires III stranded concentrically at equal intervals, and the outer diameter of each aluminum alloy wire III is 2.5 mm.

7. A high-performance OPGW optical cable with a large short-circuit current capacity according to claim 6, characterized in that: The third stranded layer is composed of four aluminum alloy wires IV stranded concentrically at equal intervals and several aluminum clad steel wires, and the four aluminum alloy wires IV and the several aluminum clad steel wires are symmetrically arranged along the circumference on the cross-section of the first stranded layer; the outer diameter of each aluminum alloy wire IV and each aluminum clad steel wire is 3.2 mm, and the type of each aluminum clad steel wire can be selected as 14% IACS, 20.3% IACS or 27% IACS according to the actual line design requirements.

8. A high-performance OPGW optical cable with a large short-circuit current capacity according to claim 7, characterized in that: The aluminum alloy wire I, the four aluminum alloy wires II, each aluminum alloy wire III, and the four aluminum alloy wires IV all adopt closely arranged high-density aluminum alloy wires, and their types are selected as LHA1 type or LHA2 type.

Images