Optoelectrical composite medium voltage cable for urban subway

Abstract

The application relates to a photoelectric composite medium-voltage cable for urban subway, which comprises a conductor, an insulation layer, a metal wire shielding layer and an outer sheath, the insulation layer is wrapped at the outer peripheral wall of the conductor, the metal wire shielding layer is wrapped at the outer peripheral wall of the insulation layer, the outer sheath is wrapped at the outer peripheral wall of the metal wire shielding layer, the metal wire shielding layer comprises a copper wire sparse winding layer and a copper belt layer, the copper wire sparse winding layer is arranged outside the insulation layer, the copper belt layer is arranged outside the copper wire sparse winding layer, and a light unit is arranged at the copper wire sparse winding layer; the insulation layer wraps the conductor, the metal wire shielding layer formed by the copper wire sparse winding layer and the copper belt layer shields external electromagnetic interference, the light unit is arranged at the copper wire sparse winding layer, the cable has power transmission and optical signal transmission functions, and the application has the effects of reasonably utilizing the cable space, compact structure and convenient subsequent maintenance operation.

Description

Technical Field

[0001] This application relates to the field of cables, and more particularly to a medium-voltage cable for urban subway systems that is a combination of optoelectronic and thermal composite. Background Technology

[0002] Medium-voltage cables for urban subways are core power transmission and distribution components of subway power supply systems, mainly used for power transmission from main substations to traction / power substations. Their design must meet stringent requirements such as high electrical performance, flame retardancy and fire resistance, moisture and corrosion resistance, and interference resistance.

[0003] Existing medium-voltage cables used in urban subways typically consist of a copper conductor, an insulation layer, a metal shielding layer, an armor layer, and an outer sheath. They have advantages such as good electrical performance, good weather resistance, good corrosion resistance, and long service life.

[0004] In the future construction and development of urban subways, with the increasing requirements for power transmission and signal transmission, it is necessary to lay signal cables separately. The outer diameter of the double-line separated cable combination is too large, which occupies a lot of space and is not conducive to construction and renovation operations as well as subsequent maintenance operations. Utility Model Content

[0005] To address the problem that laying separate signal cables is inconvenient for construction, renovation, and subsequent maintenance, this application provides a photoelectric composite medium-voltage cable for urban subways.

[0006] This application provides a photoelectric composite medium-voltage cable for urban subways, which adopts the following technical solution:

[0007] A medium-voltage optical-electric composite cable for urban subways includes a conductor, an insulation layer, a metal wire shielding layer, and an outer sheath. The insulation layer wraps around the outer peripheral wall of the conductor, the metal wire shielding layer wraps around the outer peripheral wall of the insulation layer, and the outer sheath wraps around the outer peripheral wall of the metal wire shielding layer. The metal wire shielding layer includes a copper wire unwound layer and a copper strip layer. The copper wire unwound layer is disposed outside the insulation layer, and the copper strip layer is disposed outside the copper wire unwound layer. An optical unit is disposed at the copper wire unwound layer.

[0008] By adopting the above technical solution, the insulation layer wraps the conductor, the metal wire shielding layer composed of the copper wire unwound layer and the copper strip layer shields against external electromagnetic interference, and the optical unit is set at the copper wire unwound layer. The cable has the functions of power transmission and optical signal transmission, makes reasonable use of cable space, has a compact structure, and facilitates subsequent maintenance operations.

[0009] Optionally, the conductor is wrapped with a conductor shielding layer, and the insulation layer includes a cross-linked polyethylene insulation layer and an insulation shielding layer. The cross-linked polyethylene insulation layer is wrapped around the outer peripheral wall of the conductor shielding layer, and the insulation shielding layer is wrapped around the outer peripheral wall of the cross-linked polyethylene insulation layer.

[0010] By adopting the above technical solution, wrapping the conductor shielding layer on the outside of the conductor can uniformly generate the electric field on the conductor surface. The cross-linked polyethylene insulation layer has good electrical and mechanical properties, which can effectively improve the insulation performance of the cable. The insulation shielding layer can uniformly generate the electric field on the surface of the insulation layer and enhance the operational stability of the cable.

[0011] Optionally, the insulating shielding layer is wrapped with a semiconductor water-blocking tape, the copper wire loose winding layer is wrapped around the outer peripheral wall of the semiconductor water-blocking tape, and the copper tape layer is wrapped with an insulating water-blocking tape.

[0012] By adopting the above technical solution, the semiconductor water-blocking tape wrapped around the outside of the insulating shield layer can play a certain role in blocking water. At the same time, the semiconductor water-blocking tape fills the space between the insulating shield layer and the copper tape layer, providing space for the copper wire loose winding layer to be loosely wrapped. The insulating water-blocking tape wrapped around the outside of the copper tape layer can further prevent moisture from penetrating into the cable and improve the cable's moisture resistance and electrical performance stability.

[0013] Optionally, the copper wire unwinding layer is formed by multiple sets of copper wires unwinding on the semiconductor water-blocking tape, the optical unit is wound on the semiconductor water-blocking tape, and the copper tape layer is a reverse-bundled copper tape, the reverse-bundled copper tape being in the opposite direction to the unwinding of the copper wires.

[0014] By adopting the above technical solution, multiple sets of copper wires are loosely wound to form a copper wire loose layer, which increases the flexibility and bending resistance of the cable; the optical unit is wound on the semiconductor water-blocking tape, which facilitates the orderly installation of the optical unit; the copper tape layer adopts reverse-bundled copper tape and is opposite to the copper wire loose winding direction, which enhances the overall stability and shielding performance of the cable.

[0015] Optionally, the optical unit includes an optical fiber and a stainless steel tube. The stainless steel tube is spirally wound on the semiconductor water-blocking tape. The stainless steel tube and the copper wire are wound in the same direction. The optical fiber passes through the stainless steel tube. The area enclosed by the optical fiber and the stainless steel tube is filled with filler grease.

[0016] By adopting the above technical solution, the optical fiber is run through a stainless steel tube, and a filling grease is placed in the area enclosed by the optical fiber and the stainless steel tube. The stainless steel tube protects the optical fiber from external mechanical stress and environmental factors, and the filling grease further enhances the protection and buffering effect on the optical fiber, thereby improving the stability and reliability of the optical unit's transmission performance.

[0017] Optionally, the insulating water-blocking tape is wrapped with a first high flame-retardant tape, the first high flame-retardant tape is wrapped with a metal shielding layer, and the metal shielding layer is wrapped with a second high flame-retardant tape.

[0018] By adopting the above technical solution, the outer side of the insulating water-blocking tape is wrapped with a first high flame-retardant tape, a metal shielding layer, and a second high flame-retardant tape. The first and second high flame-retardant tapes improve the flame-retardant performance of the cable, and the metal shielding layer provides further shielding.

[0019] Optionally, the metal shielding layer includes an aluminum-plastic composite strip and a brass strip, with the aluminum-plastic composite strip wrapped around the first high flame-retardant strip and the brass strip wrapped around the outer peripheral wall of the aluminum-plastic composite strip.

[0020] By adopting the above technical solution, the aluminum-plastic composite tape is wrapped around the first high flame-retardant tape, and the brass tape is wrapped around the aluminum-plastic composite tape to form a metal shielding layer, which improves the shielding performance and protection capability of the cable, reduces the probability of external electromagnetic interference affecting the cable signal transmission and power transmission, and ensures the normal and stable operation of the cable.

[0021] Optionally, a halogen-free, low-oxygen barrier layer is provided between the aluminum-plastic composite strip and the brass strip.

[0022] By adopting the above technical solution, a halogen-free low oxygen barrier layer is set between the aluminum-plastic composite tape and the brass tape, which plays a good role in oxygen barrier and improves the safety of cable use.

[0023] Optionally, the conductor is a second type of circular compressed copper conductor.

[0024] By adopting the above technical solution and using a second type of circular compressed copper conductor as the conductor of the cable, the conductivity and mechanical properties of the cable are improved, reducing power loss during power transmission and ensuring power transmission efficiency and stability.

[0025] Optionally, the outer sheath is a halogen-free, low-smoke outer sheath.

[0026] By adopting the above technical solutions, the use of halogen-free low-smoke outer sheaths can reduce the emission of smoke and toxic and harmful gases generated during cable combustion, thereby improving the environmental safety of the subway.

[0027] In summary, this application includes at least one of the following beneficial technical effects:

[0028] 1. An optical unit is installed at the copper wire unwound layer, realizing the integration of power transmission and signal transmission, avoiding the problem of excessive outer diameter of the double-wire separated cable combination, which is beneficial to construction and renovation work as well as subsequent maintenance work;

[0029] 2. Semiconductor water-blocking tape and insulating water-blocking tape serve as moisture-proof, meeting the moisture-proof requirements of cables;

[0030] 3. Halogen-free, low-smoke outer sheath with flame-retardant properties, meeting the requirements for flame-retardant and fire-resistant cables. Attached Figure Description

[0031] Figure 1 This is a cross-sectional view of the cable of this application.

[0032] Figure 2 This is an enlarged cross-sectional view of part A of this application.

[0033] Figure 3 This is an enlarged cross-sectional view of Part B of this application.

[0034] Those skilled in the art will understand that the elements in the accompanying drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the size and position of some elements in the drawings may be enlarged relative to other elements to aid in understanding the embodiments of the invention.

[0035] Reference numerals: 1. Conductor; 11. Conductor shielding layer; 2. Insulation layer; 21. Cross-linked polyethylene insulation layer; 22. Insulation shielding layer; 3. Metal wire shielding layer; 31. Copper wire loose winding layer; 32. Copper tape layer; 33. Insulating water-blocking tape; 4. Outer sheath; 5. Optical unit; 51. Optical fiber; 52. Stainless steel tube; 53. Filler grease; 6. Semiconductor water-blocking tape; 7. First high flame retardant tape; 8. Metal shielding layer; 81. Aluminum-plastic composite tape; 82. Brass tape; 83. Halogen-free low oxygen barrier layer; 9. Second high flame retardant tape. Detailed Implementation

[0036] The present application will be further described in detail below with reference to the accompanying drawings.

[0037] This application discloses a photoelectric composite medium-voltage cable for urban subway systems, referring to... Figure 1 The cable comprises a conductor 1, an insulation layer 2, a metal wire shielding layer 3, and an outer sheath 4. The insulation layer 2 wraps around the outer wall of the conductor 1, the metal wire shielding layer 3 wraps around the outer wall of the insulation layer 2, and the outer sheath 4 wraps around the outer wall of the metal wire shielding layer 3. This layered structure ensures a tight fit between the cable layers, providing protection and shielding. The metal wire shielding layer 3 includes a copper wire loose layer 31 and a copper tape layer 32. The copper wire loose layer 31 is located outside the insulation layer 2, and the copper tape layer 32 is located outside the copper wire loose layer 31, shielding against external electromagnetic interference. An optical unit 5 is installed at the copper wire loose layer 31, enabling the cable to transmit both power and optical signals. The efficient use of cable space results in a compact structure, facilitating subsequent maintenance.

[0038] Reference Figure 1 Conductor 1 adopts the second type of circular compressed copper conductor 1. The conductor 1 is circular in shape and has undergone compression treatment. The current distribution of conductor 1 is more uniform. The compression treatment increases the density of conductor 1, improves the conductivity and mechanical properties of the cable, and enables the cable to reduce power loss during power transmission, ensuring power transmission efficiency and stability.

[0039] Reference Figure 1The conductor 1 is wrapped with a conductor shielding layer 11, which can uniformly distribute the electric field on the surface of the conductor 1, reduce the phenomenon of electric field concentration, and thus improve the electrical performance stability of the cable.

[0040] Reference Figure 1 The insulation layer 2 includes a cross-linked polyethylene insulation layer 21 and an insulating shielding layer 22. The cross-linked polyethylene insulation layer 21 wraps around the outer peripheral wall of the conductor shielding layer 11, possessing excellent electrical and mechanical properties. Using cross-linked polyethylene material, its molecular chains form a three-dimensional network structure, significantly improving its heat resistance, aging resistance, and insulation performance, effectively enhancing the cable's insulation performance. The insulating shielding layer 22 wraps around the outer peripheral wall of the cross-linked polyethylene insulation layer 21, uniformly distributing the electric field on the surface of the insulation layer 2 and enhancing the cable's operational stability.

[0041] Reference Figure 1 and Figure 2 The outer side of the insulating shielding layer 22 is wrapped with a semiconductor water-blocking tape 6. The semiconductor water-blocking tape 6 can play a certain role in blocking water and preventing moisture from entering the cable. On the other hand, it fills the space between the insulating shielding layer 22 and the copper tape layer 32, providing a space for the copper wire loose winding layer 31 to be loosely wrapped.

[0042] Reference Figure 1 and Figure 2 The copper wire loose winding layer 31 is formed by multiple sets of copper wires loosely wound on the semiconductor water-blocking strip 6. The loose winding of the copper wires on the semiconductor water-blocking strip 6 increases the flexibility and bending resistance of the cable. The optical unit 5 is wound on the semiconductor water-blocking strip 6. There are two optical units 5, which are relatively distributed on both sides of the conductor 1.

[0043] Reference Figure 1 and Figure 2 The optical unit 5 includes an optical fiber 51 and a stainless steel tube 52. The stainless steel tube 52 is spirally wound on a semiconductor water-blocking tape 6, and the winding direction of the stainless steel tube 52 is the same as that of the copper wire. The optical fiber 51 passes through the stainless steel tube 52, and the area enclosed by the optical fiber 51 and the stainless steel tube 52 is filled with filler grease 53. The stainless steel tube 52 protects the optical fiber 51 from external mechanical stress and environmental factors, and the filler grease 53 further enhances the protection and buffering effect on the optical fiber 51, thereby improving the stability and reliability of the transmission performance of the optical unit 5.

[0044] Reference Figure 1 and Figure 2 The copper tape layer 32 is disposed outside the copper wire unwound layer 31. The copper tape layer 32 is a reverse-bundled copper tape, which is in the opposite direction to the copper wire unwound layer, enhancing the overall stability and shielding performance of the cable. The copper tape layer 32 can further block external electromagnetic interference and protect the conductor 1 and optical unit 5 inside the cable to ensure normal operation.

[0045] Reference Figure 1 and Figure 2 The copper tape layer 32 is wrapped with an insulating water-blocking tape 33 to further prevent moisture from penetrating the inside of the cable and improve the cable's moisture resistance and electrical performance stability.

[0046] Reference Figure 1 and Figure 2 The outer side of the insulating water-blocking tape 33 is wrapped with a first high flame-retardant tape 7, which is usually made of flame-retardant fiber material, improving the flame-retardant performance of the cable, reducing the spread of flame, and protecting the internal structure of the cable.

[0047] Reference Figure 1 and Figure 3 The first high flame-retardant strip 7 is wrapped with a metal shielding layer 8. The metal shielding layer 8 includes an aluminum-plastic composite strip 81 and a brass strip 82. The aluminum-plastic composite strip 81 is wrapped around the first high flame-retardant strip 7, and the brass strip 82 is wrapped around the outer perimeter of the aluminum-plastic composite strip 81. The aluminum-plastic composite strip 81 has good shielding and moisture-proof performance, while the brass strip 82 has high conductivity and corrosion resistance. The metal shielding layer 8 formed by the two improves the shielding performance and protection capability of the cable, reduces the probability of external electromagnetic interference affecting the cable signal transmission and power transmission, and ensures the normal and stable operation of the cable.

[0048] Reference Figure 1 and Figure 3 A halogen-free low oxygen barrier layer 83 is provided between the aluminum-plastic composite strip 81 and the brass strip 82. The halogen-free low oxygen barrier layer 83 is generally made of some inorganic materials and plays a good role in oxygen isolation. When the cable catches fire, it can reduce the oxygen supply, reduce the intensity of combustion, and improve the safety of cable use.

[0049] Reference Figure 1 and Figure 3 The outer side of the brass strip 82 is wrapped with a second high flame retardant strip 9. The second high flame retardant strip 9 works in conjunction with the first high flame retardant strip 7 to improve the flame retardant performance of the cable and further enhance the cable's safety in the event of a fire.

[0050] Reference Figure 1 and Figure 3 The outer sheath 4 is a halogen-free, low-smoke outer sheath 4. The halogen-free, low-smoke outer sheath 4 produces less smoke and toxic gases during combustion, improving the safety of the subway environment. The outer sheath 4 also has a certain degree of wear resistance and corrosion resistance, protecting the internal structure of the cable from the influence of the external environment.

[0051] The implementation principle of a photoelectric composite medium-voltage cable for urban subways in this application embodiment is as follows: The cable is arranged from the inside out as a conductor 1, an insulation layer 2, a metal wire shielding layer 3, and an outer sheath 4. An optical unit 5 is set in the metal wire shielding layer 3. Power transmission is achieved through the conductor 1, and optical signal transmission is achieved through the optical unit 5, achieving the purpose of transmitting power and optical signals in the same cable. The conductor shielding layer 11 on the outside of the conductor 1, the insulation shielding layer 22 in the insulation layer 2, and the metal wire shielding layer 3 work together to improve the electrical performance stability and anti-interference ability of the cable. The water-blocking structures such as the semiconductor water-blocking tape 6 and the insulation water-blocking tape 33 ensure the moisture-proof performance of the cable. The first high flame-retardant tape 7, the second high flame-retardant tape 9, and the halogen-free low-smoke outer sheath 4 improve the flame-retardant performance and safety of the cable.

[0052] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A photoelectric composite medium-voltage cable for urban subway, comprising a conductor (1), an insulation layer (2), a wire shielding layer (3) and an outer sheath (4), the insulation layer (2) being wrapped at the outer peripheral wall of the conductor (1), the wire shielding layer (3) being wrapped at the outer peripheral wall of the insulation layer (2), and the outer sheath (4) being wrapped at the outer peripheral wall of the wire shielding layer (3), characterized in that: The metal wire shielding layer (3) includes a copper wire unwound layer (31) and a copper strip layer (32). The copper wire unwound layer (31) is disposed outside the insulating layer (2), and the copper strip layer (32) is disposed outside the copper wire unwound layer (31). An optical unit (5) is disposed at the copper wire unwound layer (31). ​ 2. The photoelectric composite medium voltage cable for urban subway according to claim 1, characterized in that: The conductor (1) is wrapped with a conductor shielding layer (11) on the outside. The insulation layer (2) includes a cross-linked polyethylene insulation layer (21) and an insulation shielding layer (22). The cross-linked polyethylene insulation layer (21) is wrapped around the outer peripheral wall of the conductor shielding layer (11), and the insulation shielding layer (22) is wrapped around the outer peripheral wall of the cross-linked polyethylene insulation layer (21).

3. The photoelectric composite medium voltage cable for urban subway according to claim 2, characterized in that: The insulating shielding layer (22) is wrapped with a semiconductor water-blocking tape (6) on the outside, the copper wire loose winding layer (31) is wrapped around the outer peripheral wall of the semiconductor water-blocking tape (6), and the copper tape layer (32) is wrapped with an insulating water-blocking tape (33) on the outside.

4. The photoelectric composite medium voltage cable for urban subway according to claim 3, characterized in that: The copper wire loose winding layer (31) is formed by multiple sets of copper wires loosely winding around the semiconductor water-blocking tape (6), the optical unit (5) is wound around the semiconductor water-blocking tape (6), and the copper tape layer (32) is a reverse-tied copper tape, the reverse-tied copper tape being in the opposite direction to the copper wire loose winding.

5. The photoelectric composite medium voltage cable for urban subway according to claim 3, characterized in that: The optical unit (5) includes an optical fiber (51) and a stainless steel tube (52). The stainless steel tube (52) is spirally wound on the semiconductor water-blocking tape (6). The stainless steel tube (52) and the copper wire are wound in the same direction. The optical fiber (51) passes through the stainless steel tube (52). The area enclosed by the optical fiber (51) and the stainless steel tube (52) is filled with filler grease (53).

6. The photoelectric composite medium voltage cable for urban subway according to claim 3, characterized in that: The insulating water-blocking tape (33) is wrapped with a first high flame-retardant tape (7), the first high flame-retardant tape (7) is wrapped with a metal shielding layer (8), and the metal shielding layer (8) is wrapped with a second high flame-retardant tape (9).

7. The photoelectric composite medium voltage cable for urban subway according to claim 6, characterized in that: The metal shielding layer (8) includes an aluminum-plastic composite strip (81) and a brass strip (82). The aluminum-plastic composite strip (81) is wrapped around the first high flame-retardant strip (7), and the brass strip (82) is wrapped around the outer peripheral wall of the aluminum-plastic composite strip.

8. The photoelectric composite medium voltage cable for urban subway according to claim 7, characterized in that: A halogen-free low oxygen barrier layer (83) is provided between the aluminum-plastic composite strip (81) and the brass strip (82).

9. The photoelectric composite medium voltage cable for urban subway according to claim 1, characterized in that: The conductor (1) is a second type of circular compressed copper conductor (1).

10. The photoelectric composite medium voltage cable for urban subway according to claim 1, characterized in that: The outer sheath (4) is a halogen-free low-smoke outer sheath (4).

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