Intelligent high-voltage cable

Abstract

The utility model discloses an intelligent high-voltage cable, which comprises a temperature measurement optical fiber unit, a conductor layer, a conductor shielding layer, a polypropylene insulating layer, an insulation shielding layer, a semi-conductive buffer layer, an aluminum sheath, a high-density polyethylene sheath, an outer sheath and a semi-conductive layer from inside to outside in sequence, a plurality of functional optical fiber units and pressure-resistant metal wires are symmetrically arranged in the semi-conductive buffer layer; and a plurality of temperature measurement optical fiber units are arranged between the high-density polyethylene sheath and the outer sheath. The outer sheath with the structure has high insulation performance, high flame-retardant performance, environmental protection performance and the like, so that the high-voltage cable has higher performance. And meanwhile, the plurality of temperature measurement optical fiber units are spirally arranged between the two layers of sheaths and are used for monitoring the operation condition of the sheaths, and when the shielding metal sheath and the non-metal sheath are heated due to the conditions of mechanical external force, corrosion, partial discharge and the like, the temperature measurement optical fibers can transmit the monitoring condition to an intelligent platform, so that the reliability of the cable is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage cables for power transmission, in particular to an intelligent high-voltage cable. Background Art

[0002] With the development of society, people's demand for electricity is increasing, the electricity load is getting higher and higher, and the safety requirements of power supply are becoming more and more important. As the main nerve of power transmission and transformation in the power system, high-voltage cables play a vital role. As urban power supply lines are becoming more and more dense and the laying environment is becoming more and more complex, high-voltage cables will inevitably generate a lot of heat when powered on. The complex environment and heat dissipation problems cause the temperature of high-voltage cables to remain at a high temperature for a long time, which accelerates the aging of the cables. In particular, when the local temperature exceeds the safe temperature, it is easy to cause safety accidents. The existing high-voltage cables are only traditional power transmission cables, and the operation of the cables cannot be monitored. Most of them can no longer meet the safety requirements in actual use. For this reason, an intelligent high-voltage cable was invented.

[0003] Conventional high-voltage cables only transmit electrical energy. Discharge and breakdown failures caused by mechanical external forces, environmental corrosion, body defects, etc. cannot be monitored, and they do not have self-monitoring capabilities. The present invention sets a number of functional optical fiber units inside the high-voltage cable to monitor the real-time status of each layer of the cable structure when the cable is running, and develops an intelligent monitoring system. The functional optical fiber transmits the monitoring data to the intelligent system in real time. The system will process the data, display the cable operation status, and alarm in case of emergency failures, which greatly ensures the safety of the cable operation.

[0004] At present, the conductors of high-voltage power cables are mostly twisted and compressed circular or split structures. The conductor materials are copper, aluminum or aluminum alloy. The circular compressed twisted structure is to twist and compress several single wires into conductors. The split conductor is to reduce the skin effect. Several single wires are made into strands, and then the strands are assembled together. Corrugated insulating paper tapes are arranged between the strands to increase the surface area of ​​the conductor. However, the above two structures only have the ability to transmit electrical energy and cannot monitor the operation of the conductor.

[0005] Conventional high-voltage cable insulation mostly uses chemically cross-linked polyethylene (XLPE) materials. During the cross-linking process, byproducts such as acetophenone, α-methyl-styrene, and methane will be produced. If not removed in time, the life of the cable body will be affected. At the same time, the cross-linked polyethylene material cannot be recycled and reused, and its subsequent treatment is a problem, which will bring huge challenges to the environment.

[0006] During the operation of conventional high-voltage cables, due to overload, external force damage, environmental factors and other factors, the cables may have local abnormalities, but it is difficult to find them during operation and it is impossible to determine the abnormal location;

[0007] The outer sheath of conventional high-voltage cables is made of flame-retardant polyvinyl chloride (PVC) or flame-retardant polyethylene (PE). Polyvinyl chloride contains Cl elements, which will release toxic gases such as Hcl when burned, produce a lot of smoke and dust, and cause harm to personal safety. A large amount of flame retardant is added to the flame-retardant polyethylene material, which greatly reduces the volume resistivity of the polymer material and the insulation performance of the outer sheath. In particular, when the cable is laid in water or a humid environment for a long time, the insulation resistance of the outer sheath will drop sharply, which will cause cable failure in severe cases. Utility Model Content

[0008] The purpose of the utility model is to provide an intelligent high-voltage cable to solve the above technical problems existing in the use of conventional high-voltage cables.

[0009] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0010] The utility model provides an intelligent high-voltage cable, which comprises, from the inside to the outside, a temperature measuring optical fiber unit I, a conductor layer, a conductor shielding layer, a polypropylene insulation layer, an insulation shielding layer, a semi-conductive buffer layer, an aluminum sheath, a high-density polyethylene sheath, an outer sheath, and a semi-conductive layer;

[0011] The conductor layer includes a plurality of split conductors arranged in the conductor shielding layer, and the temperature measuring optical fiber unit is arranged at the center formed by the plurality of split conductors;

[0012] A plurality of functional optical fiber units and compression-resistant metal wires are symmetrically arranged in the semiconductive buffer layer;

[0013] A plurality of temperature measuring optical fiber units II are arranged between the high-density polyethylene sheath and the outer sheath.

[0014] Furthermore, the temperature measuring optical fiber unit I includes a copper tube, an optical fiber arranged in the copper tube, and an extruded semi-conductive elastomer sheath arranged outside the copper tube.

[0015] Furthermore, the functional optical fiber unit includes a stainless steel tube and a functional optical fiber arranged in the stainless steel tube.

[0016] Furthermore, the compression-resistant metal wires are symmetrically arranged on both sides of the functional optical fiber unit.

[0017] Furthermore, the temperature measuring optical fiber unit II includes an elastomeric protective layer, a tensile copper wire arranged in the elastomeric protective layer, and a temperature measuring optical fiber; wherein the tensile copper wire is symmetrically installed on both sides of the temperature measuring optical fiber.

[0018] Furthermore, the compression-resistant metal wire includes compression-resistant copper wire or aluminum wire.

[0019] Furthermore, the aluminum sheath comprises a smooth or corrugated aluminum sheath.

[0020] Furthermore, the outer sheath comprises a halogen-free, low-smoke, flame-retardant polyolefin outer sheath.

[0021] Compared with the prior art, the beneficial technical effects of the utility model are:

[0022] The present invention adds a temperature measuring optical fiber inside the conductor and connects the optical fiber to an external intelligent monitoring platform. The optical fiber can sense the temperature changes inside the conductor and transmit the data to the intelligent monitoring platform in real time to ensure the safe and stable operation of the cable.

[0023] The present invention adopts blended modified polypropylene (PP) insulation material, whose temperature resistance level and mechanical performance index are higher than cross-linked polyethylene, greatly improving the reliability of the cable. It does not need cross-linking, greatly reduces energy consumption, and does not produce any by-products. At the same time, it can be recycled and reused, which is very environmentally friendly.

[0024] The present invention evenly places 4 functional optical fiber units along the circumferential direction between two layers of semi-conductive buffer belts, and places 2 round copper wires or aluminum wires on both sides of each optical fiber unit, the diameter of the copper wires or aluminum wires is larger than the diameter of the functional optical fiber unit, so as to protect the optical fiber unit from damage during manufacturing, transportation, laying, etc. The functional optical fiber unit can sense the changes in physical quantities such as temperature, pressure, and stress of the cable body, and transmit the monitored data to the intelligent monitoring platform in real time through the Raman scattering effect. The intelligent platform realizes the monitoring of cable operation, abnormal alarm and fault location through software processing, and ensures the stability of cable operation.

[0025] The outer sheath of the present invention adopts a double-layer structure, that is, the inner layer is high-density polyethylene, which has an ultra-high volume resistivity of 1×1014Ω·m, and at the same time, it is not easy to absorb water, ensuring the insulation performance. The outer layer adopts extruded halogen-free low-smoke flame-retardant polyolefin sheath material, which has high flame retardant performance, does not produce harmful gases when burning, has a small amount of smoke, and can meet the flame retardant A-level test requirements.

[0026] The outer sheath of this structure has high insulation performance, high flame retardancy and environmental protection, which makes the high-voltage cable have higher performance. At the same time, 4 temperature measurement optical fiber units are spirally set between the two layers of sheath to monitor the operation of the sheath. When the shielded metal sheath and non-metallic sheath heat up due to mechanical external force, corrosion, partial discharge, etc., the temperature measurement optical fiber will transmit the monitoring situation to the intelligent platform, which greatly improves the reliability of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The utility model will be further described below in conjunction with the accompanying drawings.

[0028] Figure 1It is a schematic diagram of the internal main structure of the cable of the present application along the radial direction of the outer layer;

[0029] Figure 2 It is a schematic diagram of the internal main structure of the split conductor internal temperature measurement optical fiber unit;

[0030] Figure 3 It is a schematic diagram of the internal main structure of the functional optical fiber unit in the semi-conductive buffer layer;

[0031] Figure 4 It is a schematic diagram of the internal main structure of the temperature measuring optical fiber unit between the inner and outer sheaths;

[0032] Figure 5 yes Figure 1 Schematic diagram of the structure of the conductor shielding layer.

[0033] Explanation of the reference numerals in the accompanying drawings: 1. Temperature measuring optical fiber unit; 1-1. Optical fiber; 1-2: Copper tube; 1-3: Extruded semi-conductive elastomer sheath; 2. Divided conductor; 3. Conductor shielding layer; 4. Polypropylene insulation layer; 5. Insulation shielding layer; 6. Functional optical fiber unit; 6-1. Functional optical fiber; 6-2: Stainless steel tube; 7. Compression-resistant metal wire; 8. Semi-conductive buffer layer; 9. Aluminum sheath; 10. High-density polyethylene sheath; 11. Temperature measuring optical fiber unit; 11-1. Temperature measuring optical fiber; 11-2: Tensile-resistant copper wire; 11-3: Elastomer protective layer; 12. Outer sheath; 13. Semi-conductive layer. DETAILED DESCRIPTION

[0034] This embodiment discloses an intelligent high-voltage cable, which includes, from inside to outside, a temperature measuring optical fiber unit Ⅰ1, a conductor layer, a conductor shielding layer 3, a polypropylene insulation layer 4, an insulation shielding layer 5, a semi-conductive buffer layer 8, an aluminum sheath 9, a high-density polyethylene sheath 10, an outer sheath 12, and a semi-conductive layer 13;

[0035] like Figure 5 As shown, the conductor layer includes a plurality of split conductors 2 installed in the conductor shielding layer 3, wherein the split conductors 2 are petal-shaped structures; the temperature measuring optical fiber unit Ⅰ1 is installed at the center formed by the plurality of split conductors 2;

[0036] like Figure 1 As shown, in this embodiment, a plurality of functional optical fiber units 6 and compression-resistant metal wires 7 are symmetrically installed in the semi-conductive buffer layer 8;

[0037] A plurality of temperature measuring optical fiber units II 11 are installed between the high-density polyethylene sheath 10 and the outer sheath 12 .

[0038] In this embodiment, the temperature measuring optical fiber unit Ⅰ1 includes a copper tube 1-2, an optical fiber 1-1 installed in the copper tube 1-2, and an extruded semi-conductive elastomer sheath 1-3 installed outside the copper tube 1-2.

[0039] In this embodiment, Figure 3 As shown, the functional optical fiber unit 6 includes a stainless steel tube 6-2 and a functional optical fiber 6-1 installed in the stainless steel tube 6-2.

[0040] In this embodiment, Figure 1 As shown, the compression-resistant metal wire 7 is symmetrically installed on both sides of the functional optical fiber unit 6.

[0041] In this embodiment, Figure 2 As shown, the temperature measuring optical fiber unit II11 includes an elastomeric protective layer 11-3, a tensile copper wire 11-2 installed in the elastomeric protective layer 11-3, and a temperature measuring optical fiber 11-1; wherein the tensile copper wire 11-2 is symmetrically installed on both sides of the temperature measuring optical fiber 11-1.

[0042] In this embodiment, the compression-resistant metal wire 7 includes compression-resistant copper wire or aluminum wire; the aluminum sheath 9 includes a smooth or corrugated aluminum sheath; and the outer sheath 12 includes a halogen-free, low-smoke, flame-retardant polyolefin outer sheath.

[0043] In order to improve the safety, intelligence and environmental protection of high-voltage cables, the present invention applies for an intelligent high-voltage cable, and the technical scheme is as follows; it includes a temperature measuring split conductor, and the split conductor has a built-in temperature measuring optical fiber unit; a three-layer structure of a co-extruded conductor semi-conductive shielding layer, a cross-linked polyethylene insulation layer, and an insulating semi-conductive shielding layer outside the conductor; a semi-conductive buffer layer is wrapped around the insulating core; four functional optical fiber units are spirally placed between the semi-conductive buffer belts; a smooth or corrugated aluminum sheath is on the outside of the buffer layer; an asphalt anti-corrosion layer is coated on the outside of the aluminum sheath; a high-density polyethylene inner sheath and a halogen-free, low-smoke, flame-retardant polyolefin outer sheath are extruded in sequence outside the asphalt anti-corrosion layer, and four temperature measuring optical fiber units are spirally placed between the two sheaths; the outermost layer is coated or extruded with a semi-conductive layer. The present invention is an intelligent high-voltage cable with high safety, high reliability and environmental protection.

[0044] The present invention arranges several functional optical fiber units inside the high-voltage cable, which can monitor the real-time status of each layer structure when the cable is running, and develops a matching intelligent monitoring system. The functional optical fiber transmits the monitoring data to the intelligent system in real time. The system will process the data, display the cable operation status, and alarm in case of emergency failure, which greatly ensures the safety of cable operation.

[0045] A temperature measuring optical fiber is added inside the conductor and connected to an external intelligent monitoring platform. The optical fiber can sense the temperature changes inside the conductor and transmit the data to the intelligent monitoring platform in real time to ensure the safe and stable operation of the cable.

[0046] The insulation material is modified polypropylene (PP), which has higher temperature resistance and mechanical performance than cross-linked polyethylene, greatly improving the reliability of the cable. It does not require cross-linking, greatly reduces energy consumption, does not produce any by-products, can be recycled and reused, and is very environmentally friendly.

[0047] Four functional optical fiber units are evenly placed along the circumferential direction between two layers of semi-conductive buffer belts, and two round copper or aluminum wires are placed on both sides of each optical fiber unit. The diameter of the copper or aluminum wire is larger than that of the functional optical fiber unit to protect the optical fiber unit from damage during manufacturing, transportation, and laying. The functional optical fiber unit can sense changes in physical quantities such as temperature, pressure, and stress of the cable body, and transmit the monitored data to the intelligent monitoring platform in real time through the Raman scattering effect. The intelligent platform can monitor the operation of the cable, alarm abnormalities, and locate faults through software processing to ensure the stability of the cable operation.

[0048] The outer sheath of the present invention adopts a double-layer structure, that is, the inner layer is high-density polyethylene, which has an ultra-high volume resistivity of 1×1014Ω·m. At the same time, it is not easy to absorb water, ensuring the insulation performance. The outer layer adopts extruded halogen-free low-smoke flame-retardant polyolefin sheath material, which has high flame retardant properties. When burned, it does not produce harmful gases, the amount of smoke is small, and it can meet the flame retardant Class A test requirements. The outer sheath of this structure has high insulation performance, high flame retardancy and environmental protection, etc., so that the high-voltage cable has higher performance. At the same time, 4 temperature measuring optical fiber units are spirally arranged between the two layers of sheath to monitor the operation of the sheath. When the shielded metal sheath and non-metallic sheath are heated due to mechanical external force, corrosion, local discharge, etc., the temperature measuring optical fiber will transmit the monitoring situation to the intelligent platform, which greatly improves the reliability of the cable.

[0049] Application Examples

[0050] The present invention is an intelligent high voltage cable. Figure 1 , Figure 2 , Figure 3 , Figure 4, including a temperature measuring optical fiber unit Ⅰ1 for monitoring the temperature of the conductor, and a conductor 2 divided outside the optical fiber unit; a three-layer co-extrusion process is adopted outside the conductor, and a conductor shielding layer 3 for uniform electric field, a cross-linked polyethylene insulation layer 4, and an insulation shielding layer 5 are extruded; a semi-conductive buffer tape 8 is wrapped around the insulation shielding layer to buffer the deformation caused by the thermal expansion and contraction of the insulation during the operation of the cable, and to prevent the spread of water after the cable enters the cable; a protective copper wire or aluminum wire 7 and a functional optical fiber unit 6 are arranged in the buffer layer to sense the ratio change of physical quantities such as temperature, pressure, and stress of the cable body, so as to monitor the operation of the cable; a smooth or corrugated aluminum sheath 9 is provided outside the buffer layer, and the corrugated aluminum sheath is in full contact with the semi-conductive buffer tape, which plays the role of metal shielding and armoring, and radial water blocking; its outer layer is extruded with a high-density polyethylene inner sheath layer 10, which has an ultra-high volume resistivity of 1×1014Ω·m, and at the same time, it is extremely difficult to absorb water, thereby ensuring the insulation performance. The outer extruded halogen-free, low-smoke, flame-retardant polyolefin sheath layer 12 has high flame-retardant properties. When burned, it does not produce harmful gases, produces little smoke, and can meet the flame-retardant Class A test requirements. A temperature measuring optical fiber unit is spirally arranged between the polyethylene inner sheath 10 and the halogen-free, low-smoke, flame-retardant polyolefin sheath layer 12 to monitor the operating temperature of the sheath. The outermost layer is a coated or extruded semi-conductive layer 13.

[0051] The above embodiments are only descriptions of the preferred methods of the invention, and are not intended to limit the scope of the invention. Without departing from the design spirit of the invention, various modifications and improvements made to the technical solution of the invention by ordinary technicians in this field should fall within the protection scope of the claims of the invention.

Claims

1. An intelligent high-voltage cable, characterized in that: The device comprises, from the inside to the outside, a temperature measuring optical fiber unit I (1), a conductor layer, a conductor shielding layer (3), a polypropylene insulating layer (4), an insulating shielding layer (5), a semi-conductive buffer layer (8), an aluminum sheath (9), a high-density polyethylene sheath (10), an outer sheath (12), and a semi-conductive layer (13); The conductor layer includes a plurality of split conductors (2) arranged in the conductor shielding layer (3), and the temperature measuring optical fiber unit I (1) is arranged at the center formed by the plurality of split conductors (2); A plurality of functional optical fiber units (6) and compression-resistant metal wires (7) are symmetrically arranged in the semi-conductive buffer layer (8); A plurality of temperature measuring optical fiber units II (11) are arranged between the high-density polyethylene sheath (10) and the outer sheath (12).

2. The intelligent high-voltage cable according to claim 1, characterized in that: The temperature measuring optical fiber unit I (1) comprises a copper tube (1-2), an optical fiber (1-1) arranged in the copper tube (1-2), and an extruded semi-conductive elastomer sheath (1-3) arranged outside the copper tube (1-2).

3. The intelligent high-voltage cable according to claim 1, characterized in that: The functional optical fiber unit (6) comprises a stainless steel tube (6-2) and a functional optical fiber (6-1) arranged in the stainless steel tube (6-2).

4. The intelligent high-voltage cable according to claim 3, characterized in that: The compression-resistant metal wires (7) are symmetrically arranged on both sides of the functional optical fiber unit (6).

5. The intelligent high-voltage cable according to claim 1, characterized in that: The temperature measuring optical fiber unit II (11) comprises an elastomeric protective layer (11-3), a tensile copper wire (11-2) arranged in the elastomeric protective layer (11-3), and a temperature measuring optical fiber (11-1); wherein the tensile copper wire (11-2) is symmetrically installed on both sides of the temperature measuring optical fiber (11-1).

6. The intelligent high-voltage cable according to claim 1, characterized in that: The compression-resistant metal wire (7) comprises compression-resistant copper wire or aluminum wire.

7. The intelligent high-voltage cable according to claim 1, characterized in that: The aluminum sheath (9) comprises a smooth or corrugated aluminum sheath.

8. The intelligent high-voltage cable according to claim 1, characterized in that: The outer sheath (12) comprises a halogen-free, low-smoke, flame-retardant polyolefin outer sheath.

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