RU145334U1 - ELECTRIC POWER CABLE - Google Patents

Abstract

A design of a power electric cable with plastic insulation and residential grounding, used for the transmission and distribution of electrical energy in stationary electrical installations, is proposed. In order to increase operational characteristics and reduce the price, the cable grounding conductor is made of a single layer of aluminum or its alloy wires, including copper coated, modified with rare or rare earth metals, or alkaline or alkaline earth metals, or semiconductor materials, or mixtures thereof, including from superplastic aluminum alloys with an ultrafine-grained or nanocrystalline structure, for example, from a thermocorrosion-resistant aluminum alloy of the TAS-18 brand modified with circus nium and yttrium, arranged in a spiral over the belt insulation and fastened with tape or a pile of electrically conductive material. The new cable is high-tech and has enhanced quality and reliability.

Description

The utility model relates to cable technology, namely, to the designs of power electrical cables with plastic insulation and residential grounding, used for transmission and distribution of electrical energy in stationary electrical installations.

In power electric cables, a grounding conductor is used to connect non-energized metal parts of electrical installations with a protective earth circuit.

The closest to the utility model in its parameters is a power cable with plastic insulation in accordance with GOST Ρ 53769-2010, commissioning year 2010, Russia, (prototype), containing copper or aluminum insulated conductive conductors, including main conductors and zero or without conductors, and insulated grounding conductor, twisted into a core, filling the gaps between the cores with a tow of non-hygroscopic fibrous or polymeric materials or without it, belt insulation over the core in the form of an extrudable inner sheath or polymer winding tapes, a screen made of copper tapes or copper wires on top of or without belt insulation, a pillow on top of the screen from an extruded shell or wrapped with polymer tapes or without it, armor made of galvanized steel tapes or steel galvanized wires or wires of aluminum or aluminum alloy or without it, the separation layer on top of the armor of the extrudable shell or winding with or without polymer tapes and the outer shell of polymeric materials, including low combustibility, or low fire risk, or not won a halogen.

The disadvantages of the prototype include:

- increased weight of the cable with copper conductor grounding;

- increased cost of cable with copper conductor grounding;

- reduced reliability of the cable with aluminum core grounding.

All these disadvantages of the prototype significantly reduce operational

- characteristics and scope of power cables with plastic insulation.

The technical task of the utility model is the development of a power electric cable that is not inferior to the prototype in basic characteristics, and at the same time more reliable and economical. The technical result is achieved by the fact that the grounding conductor is made of a single layer of aluminum or its alloy wires, including copper coated, modified with rare or rare-earth metals from the group: zirconium, scandium, yttrium, cerium, lanthanum, vanadium, hafnium, or alkaline or alkaline earth metals from the group: lithium, beryllium, magnesium, calcium, strontium, or semiconductor materials from the group: boron, tellurium, selenium, germanium, silicon, or mixtures thereof, including from superplastic alloys of aluminum with ultrafine-grained th or nanocrystalline structure, located in a spiral over the belt insulation and fastened with tape or a pile of electrically conductive material.

A common feature of the prototype and the proposed technical solution is the presence of insulated conductive conductors, including main conductors and a neutral conductor with or without it, and ground conductors made of copper or aluminum, filling the gaps between the conductors or without it, waist insulation of conductive conductors, a copper shield or without him, pillows on top of the screen or without it, armor or without it, the separation layer on top of the armor or without him and the outer shell.

At the same time, the proposed cable differs from the known one using a grounding conductor made of a single layer of aluminum or its alloy wires, including copper coated, modified with rare or rare-earth metals from the group: zirconium, scandium, yttrium, cerium, lanthanum, vanadium, hafnium , or alkaline or alkaline earth metals from the group: lithium, beryllium, magnesium, calcium, strontium, or semiconductor materials from the group: boron, tellurium, selenium, germanium, silicon, or mixtures thereof, including superplastic alloys aluminum alloys with an ultrafine-grained or nanocrystalline structure, arranged in a spiral over the belt insulation and fastened with tape or a pile of electrically conductive material.

A single-layer grounding conductor made of wires arranged in a spiral over the belt insulation simultaneously plays the role of a screen, protecting the cable from the effects of electric and electromagnetic fields, reducing the influence of the electric field of the cable on adjacent cables in the bundle and increasing the electrical strength of the insulation of conductive cores. At the same time, there is no need to make a copper screen, which leads to a decrease in the mass and cost of the cable. A tape or web of electrically conductive material provides electrical contact between the wires of the ground conductor over the entire surface of the cable. The tape or web also fixes the wires of the grounding conductor at a certain distance from each other and prevents the displacement and overlap of the wires when a separating layer and a plastic sheath are applied to the cable. This significantly improves the manufacturability of cable manufacturing and increases the efficiency of the grounding conductor.

In order to increase the heat resistance, corrosion resistance, mechanical strength and flexibility of grounding wires, the authors of the utility model suggest using aluminum or its alloys modified by rare or rare-earth metals, or alkaline or alkaline-earth metals, or semiconductor materials, or mixtures thereof, for the manufacture of grounding wires. including superplastic aluminum alloys with an ultrafine-grained or nanocrystalline structure obtained by the physicomechanical method E.

Small additives (up to 0.5 wt.%) Of rare and rare-earth metals can significantly increase the strength, ductility, heat resistance and corrosion resistance of aluminum and its alloys by grinding grain. For example, the addition of cerium in an amount of 0.5 wt.% Increases the strength, ductility and heat resistance of aluminum almost twice. This reduces corrosion by 10 times and significantly increases the electrical conductivity of aluminum. The addition of 0.3 wt.% Yttrium increases the electrical conductivity of aluminum by 7.5%, and also increases its strength, ductility and heat resistance. The addition of 0.4 wt.% Scandium increases the strength of aluminum by 35%. This increases the ductility, electrical conductivity and heat resistance of aluminum. The addition of zirconium to 0.5 wt.% Allows you to significantly (2-2.5 times) increase the heat resistance and ductility of aluminum and its alloys without reducing electrical conductivity. Small additives (up to 5.0 wt.%) Of alkali or alkaline earth metals from the group: lithium, beryllium, magnesium, calcium, strontium, or semiconductor materials from the group: boron, tellurium, selenium, germanium, silicon, or mixtures thereof can increase the ductility , strength and electrical conductivity of aluminum and its alloys. Superplastic alloys of aluminum with an ultrafine-grained or nanocrystalline structure can be obtained mechanically or physically. The mechanical method is based on the phenomenon of deformation grinding of the grain structure of a metal during intense plastic deformation (IPD). IPD methods: equal channel angular pressing, torsional deformation, screw extrusion, all-round forging. These methods make it possible to obtain aluminum alloys with grain sizes from hundreds to tens of nanometers with a unique set of physicomechanical properties, including high-speed superplasticity, super strength, and superconductivity. The physical method for producing superplastic aluminum alloys with an ultrafine-grained structure is based on casting in a high-frequency electromagnetic field. This method allows to obtain ultra-thin and heavy-duty wire from aluminum alloys of conductive purpose with high electrical conductivity, which does not lose its properties during prolonged use at high temperatures. Aluminum and its alloys modified with rare or rare-earth metals have practically no creep under load. The copper coating of the wires of the ground conductor can increase the reliability of grounding.

For the manufacture of wires and a fastening tape for the grounding conductor of a power electric cable, the authors of the utility model developed a thermocorrosion-resistant aluminum alloy of the TAC-18 brand according to TU 1712-043-50289046-2012, the year of entry 2012, Russia, modified with zirconium and yttrium. This alloy has increased indicators of mechanical strength, ductility, heat resistance, corrosion resistance and electrical conductivity. For the manufacture of insulation of the main and zero conductive cores, PVC plastic compounds or polyolefins, for example cross-linked polyethylene, can be used. To fill the gaps between the insulated conductors, fillers from extrusion, or tape, or fibrous materials, including water-blocking materials, for example, filler cable polypropylene finely filled ZKPm in the form of a bundle of perforated tape, can be used. Extruded polymers, or polymer tapes, or mineral tapes, including low flammability, for example, tapes from a film of polyethylene-propylene electrical insulating low-combustible grade PEP-Etg, can be used as a belt insulation of conductive conductors. The new cable may also additionally contain a shield from electrically conductive extrudable materials, or electrically conductive polymer tapes, or electrically conductive mineral tapes, or electrically conductive water-blocking tapes, including reduced combustibility, for example, a screen made of electrically conductive fiberglass brand TES, between the zone insulation and the residential earth. As a separation layer between the residential ground and the outer shell, a winding made of polymer, or mineral, or water blocking tapes, including electrically conductive ones, including reduced combustibility, for example a glass tape winding, can be used. For the manufacture of the outer shell, polyolefins or PVC compounds, including reduced flammability, can be used. Materials of ZKPm, PEP-Etg and TPP brands are developed and produced at NPK Energia LLC.

The power electric cable according to the utility model (Fig.) Contains the main and zero conductive conductors 1 of copper or aluminum, polymer insulation 2 of the main and zero conductive conductors, filler 3 of the gaps between the conductors, belt insulation 4, screen 5 of conductive non-metallic materials, ground conductor of wires 6 and a fastening tape 7 of a modified aluminum alloy, the separation layer 8 and the outer polymer sheath 9. The electric power cable according to the prototype is made by the following technology. Polymer insulation, for example, cross-linked polyethylene, is applied to copper or aluminum main and zero conductive conductors. The thickness of the insulation depends on the brand of cable. The main and zero insulated conductive wires are twisted together into the core on a twisting machine with a certain twisting pitch. At the same time, a filler made of extrusion, or tape, or fibrous materials, including water blocking materials, for example, filler cable polypropylene finely filled ZKPm in the form of a bundle of perforated tape, is laid in the gaps between the cores. It is possible to manufacture cable without filler. On top of the core of twisted cores, belt insulation is applied from extruded polymers, or polymer tapes, or mineral tapes, including reduced combustibility, for example, one tape with overlap or two tapes with a gap from a film of polyethylene-propylene electrical insulating low-combustible grade PEP-Etg. A shield of electrically conductive extrudable materials, or electrically conductive polymer tapes, or electrically conductive mineral tapes, or electrically conductive water blocking tapes, including reduced flammability, for example, from TES electrically conductive fiberglass tapes, is additionally superimposed on top of the waist insulation. It is possible to manufacture a cable without a screen. A single-layer ground conductor of aluminum or its alloys, including copper coated with rare or rare-earth metals, or alkaline or alkaline-earth metals, or semiconductor materials, or mixtures thereof, including superplastic alloys, is superimposed on top of the screen of electrically conductive non-metallic materials. aluminum with an ultrafine-grained or nanocrystalline structure, for example, of a TAC-18 thermocorrosion-resistant aluminum alloy modified with zirconium and yttrium. The wires of the grounding conductor are laid in a spiral at a certain distance from each other and are fastened with a tape or a pile of electrically conductive material, for example, of a modified aluminum alloy of the TAS-18 brand. On top of the earth conductor, a winding layer is applied by winding from polymer, or mineral, or water blocking tapes, including electrically conductive ones, including reduced combustibility, for example, from glass tape. It is possible to manufacture a cable without a separation layer. An outer casing made of polymeric materials, including low flammability, for example, low flammability PVC compound, is applied by extrusion on top of the separation layer. Advantages of the new cable:

- high dielectric strength;

- high manufacturability and quality;

- increased reliability;

- reduced cost.

Power cables with plastic insulation for voltages up to 6 kV with a single-layer multi-wire conductor grounding made of TAC-18 aluminum alloy modified with zirconium and yttrium, located on top of the belt insulation of the cable, have passed comprehensive tests at cable plants in the Russian Federation with positive results. Production of these cables has been established.

Claims (12)

1. An electric power cable with plastic insulation, containing insulated conductive conductors, including main conductors and a neutral conductor or without it, an earth conductor, filling the gaps between conductors or without it, waist insulation of conductive conductors, a copper shield or without it, a pillow over the screen or without it, armor with or without it, a separation layer on top of the armor or without it and an outer shell, characterized in that the grounding conductor is made of a single layer of aluminum or its alloy wires, including copper-plated, modified of rare or rare earth metals from the group: zirconium, scandium, yttrium, cerium, lanthanum, vanadium, hafnium, or alkaline or alkaline earth metals from the group: lithium, beryllium, magnesium, calcium, strontium, or semiconductor materials from the group: boron, tellurium, selenium, germanium, silicon, or mixtures thereof, including from superplastic aluminum alloys with an ultrafine-grained or nanocrystalline structure, arranged in a spiral over the belt insulation and fastened with tape or scrap from an electrically conductive material. 2. An electric power cable with plastic insulation according to Claim 1, characterized in that the wires and the fastening tape of the grounding conductor are made of a TAC-18 thermocorrosion-resistant aluminum alloy modified with zirconium and yttrium. 3. Electric power cable with plastic insulation according to claim 1, characterized in that the main and zero conductive conductors are insulated with cross-linked polyethylene. 4. An electric power cable with plastic insulation according to claim 1, characterized in that a filler made of extrusion, or tape, or fibrous materials, including water blocking, is used to fill the gaps between the main and zero insulated conductive conductors. 5. An electric power cable with plastic insulation according to claim 1, characterized in that for filling the gaps between the main and zero insulated conductive conductors, a cable filler polypropylene finely filled ZKPm in the form of a bundle of perforated tape is used. 6. An electric power cable with plastic insulation according to claim 1, characterized in that extruded polymers, or polymer tapes, or mineral tapes, including low combustibility, are used as the zone insulation of conductive conductors. 7. An electric power cable with plastic insulation according to claim 1, characterized in that tapes made of a film of polyethylene-propylene electrical insulating slow-burning grade PEP-Etg are used as a zone insulation of conductive conductors. 8. An electric power cable with plastic insulation according to claim 1, characterized in that between the belt insulation and the residential ground there is additionally a screen of electrically conductive extrudable materials, or electrically conductive polymer tapes, or electrically conductive mineral tapes, or electrically conductive water blocking tapes, including low flammability. 9. An electric power cable with plastic insulation according to claim 1, characterized in that between the zone insulation and the residential ground there is additionally a screen made of electrically conductive fiberglass brand TES. 10. An electric power cable with plastic insulation according to claim 1, characterized in that between the residential earth and the outer sheath there is a separation layer of polymer, or mineral, or water blocking tapes, including electrically conductive, including low combustibility. 11. Electric power cable with plastic insulation according to claim 1, characterized in that between the earth ground and the outer sheath there is a separation layer of glass tape. 12. An electric power cable with plastic insulation according to claim 1, characterized in that a low flammability PVC compound is used as the outer sheath.