WO2020094004A1

WO2020094004A1 - Low-voltage wind energy cable

Info

Publication number: WO2020094004A1
Application number: PCT/CN2019/115706
Authority: WO
Inventors: 马振清; 曹西伟; 宋文娜; 万育萍
Original assignee: 江苏亨通电力电缆有限公司
Priority date: 2018-11-06
Filing date: 2019-11-05
Publication date: 2020-05-14
Also published as: CN209374105U

Abstract

A low-voltage wind energy cable (100), which relates to the technical field of cables. The low-voltage wind energy cable (100) comprises a conductor (10), an isolation band (20), an insulation layer (30), and an outer sheath (40). The isolation band (20) wraps the exterior of the conductor (10). The insulation layer (30) wraps the exterior of the isolation band (20), and the material of the insulation layer (30) is ethylene propylene rubber. The outer sheath (40) wraps the exterior of the insulation layer (30). The cable (100) having said structural design has a broad range of applications and has comprehensive advantages such as power transmission and high mechanical strength. Moreover, the cable (100) does not require the addition of new production equipment to achieve the production of the low-voltage wind energy cable (100), which saves production costs. The cable has excellent flexibility and does not easily break during use; in addition, the insulation layer (30) of the low-voltage wind energy cable (100) uses an ethylene propylene rubber material having better flame retardant performance and tensile strength, and the outer sheath (40) uses chlorinated polyethylene rubber having better flame retardant performance, oil resistance, and low temperature resistance such that the finished product of the low-voltage wind energy cable (100) may pass the FT4 flame test under UL 1685.

Description

Low-voltage wind energy cable

This application requires the priority of the utility model patent application with the application number 201821816645.2 submitted to the State Intellectual Property Office of China on November 6, 2018. The content of the priority text is expressly incorporated by reference into this application.

Technical field

This application relates to the technical field of cables, in particular, to a low-voltage wind energy cable.

Background technique

At present, wind power generation has become the generation method of new energy with the technology maturity, the highest scale development conditions and the best commercial development prospects. The scale of the global wind power industry has attracted attention. As a supporting product for wind power-wind power cables It is becoming a new cable product with huge market potential, and the US cable market is currently the world's largest regional market. The requirements of the American standard wire and cable are almost the top requirements of products in the global wire and cable industry, Europe, North America and the world. Other countries and regions within the scope of the wind power cable mostly use the US UL standard. In these countries and regions, the industry access system usually implements the US UL certification, which greatly raises the technical access threshold.

The flame retardant properties of the insulation materials and outer sheath materials commonly used in domestic conventional American standard torsion-type low-voltage wind energy rubber sheathed flexible cables can only pass the flame retardant CT test specified in UL 1685; and the tensile strength of the insulation materials used Low strength (4.2Mpa) and poor flame retardant performance; outer sheath oil resistance index (100 ℃, 24h, tensile strength and elongation rate of change ± 40%) is low; flame retardant, high mechanical properties , Cold resistance and oil resistance are not satisfied at the same time.

Application content

The purpose of this application is to provide a low-voltage wind energy cable to improve the problem of poor flame retardancy and softness of existing low-voltage wind energy cables.

This application is implemented as follows:

Based on the above purpose, the present application provides a low-voltage wind energy cable, including a conductor, an isolation tape, an insulation layer and an outer sheath, the isolation tape is wrapped around the outside of the conductor, and the insulation layer is wrapped around the outside of the isolation tape The material of the insulating layer is ethylene-propylene rubber, and the outer sheath is wrapped outside the insulating layer.

In the above technical solution, the cable insulation layer material is ethylene-propylene rubber. This ethylene-propylene rubber insulation material not only enables the cable product to pass the flame retardant FT4 test in UL1685, but also the flame-retardant high-strength ethylene-propylene insulation rubber material has a tensile strength exceeding Double the ordinary ethylene-propylene rubber insulation material, the flame retardant performance and electrical safety performance of the low-voltage wind energy cable are improved, and the cable with this structural design has a wide range of applications, with comprehensive advantages such as power transmission and high mechanical strength, and the cable Production can be produced only through the factory's existing production equipment.

Further, the conductor includes a plurality of strands, the strands are twisted to form the conductor, and each strand of the strand includes a plurality of copper wires, the plurality of copper wires are stranded to form each strand Tow.

In the above technical solution, the conductor includes a multi-strand tow, the tow includes a plurality of copper wires, and the tow is formed by twisting a plurality of copper wires. Choosing the copper wire as the basic unit of the conductor not only makes the knife body have good wire performance , Can also ensure the flexibility of the conductor.

Further, the plurality of copper wires are twisted along a first circumferential direction to form the tow, the multiple strands are twisted along a second circumferential direction to form the conductor, and the first circumferential direction is connected to the first The two circumferential directions are opposite.

In the above technical solution, the conductor includes multiple strands, and the conductor is formed by stranding multiple strands, the strand includes multiple copper wires, and the strand is formed by stranding multiple copper wires. The selection of wires can make the low-voltage wind energy cable have better flexibility.

Further, the tow includes a first copper wire layer, a second copper wire layer, and a third copper wire layer arranged in order from inside to outside, and the outer diameter of the copper wire in the second copper wire layer is less than The outer diameter of the copper wire in the second copper wire layer and the outer diameter of the copper wire in the third copper wire layer.

In the above technical solution, the second copper wire layer can fill a part of the gap between the third copper wire layer and the first copper wire layer, making the tow structure more compact and reducing the possibility of partial discharge.

Further, the ratio of the outer diameter of the copper wire to the pitch length of the tow is 1: 8.

In the above technical solution, limiting the ratio of the outer diameter of the copper wire to the pitch length of the tow to 1: 8 can make the tow not only have better flexibility, but also ensure a compact structure of the tow.

Further, the ratio of the outer diameter of the tow to the pitch length of the conductor is 1: 8.

In the above technical solution, limiting the ratio of the outer diameter of the tow to the pitch length of the conductor to 1: 8 enables the conductor to have better flexibility and also ensure a compact structure of the conductor.

Further, the diameter of the copper wire is 0.45 mm to 0.55 mm.

In the above technical solution, the flexibility of the conductor is ensured by limiting the diameter of the copper wire to a relatively small range.

Further, the diameter of the conductor is 1.5mm-37.4mm.

In the above technical solution, the diameter of the limited conductor is within a reasonable range, while ensuring the flexibility and power transmission performance of the cable, the number of copper wires per tow can be reasonably adjusted.

Further, the outer sheath material is chlorinated polyethylene rubber.

In this embodiment, the chlorinated polyethylene rubber material selected for the outer sheath has better flame retardancy, oil resistance, low temperature resistance and ultraviolet resistance than ordinary chlorinated polyethylene rubber materials.

Further, the insulating layer and the outer sheath are coated on the outside of the conductor by double-layer co-extrusion.

In this embodiment, the double-layer simultaneous sequential extrusion method can avoid problems such as contamination and damage to the inner insulating surface when the two extrusions are separated, and the two adjacent layers of insulation are closely combined to improve Cable quality.

The beneficial effects of this application include:

This application provides a low-voltage wind energy cable, including conductor, isolation tape, insulation layer and outer sheath; the cable insulation layer material is ethylene-propylene rubber, this ethylene-propylene rubber insulation material can not only make the finished cable pass UL1685 flame retardant FT4 test , And the tensile strength of this flame-retardant high-strength ethylene-propylene insulation rubber material is more than twice that of ordinary ethylene-propylene rubber insulation materials, so that the flame retardant performance and electrical safety performance of the low-voltage wind energy cable are improved, and the cable of this structural design is suitable for It has a wide range, has comprehensive advantages such as power transmission and high mechanical strength, and the cable can realize the production of the low-voltage wind energy cable without adding new production equipment, saving the production cost.

BRIEF DESCRIPTION

In order to more clearly explain the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, so they are not It should be regarded as a limitation on the scope. For those of ordinary skill in the art, without paying any creative work, other related drawings can be obtained based on these drawings.

1 is a schematic structural diagram of a low-voltage wind energy cable provided in Example 1 of this application;

2 is a schematic diagram of the structure of the tow shown in FIG. 1;

3 is a schematic structural diagram of a low-voltage energy distribution cable provided in Example 2 of the present application;

4 is a schematic structural view of the tow shown in FIG. 3;

Icon: 100-low-voltage wind energy cable; 10-conductor; 11-tow; 111-first copper conductor layer; 112-second copper conductor layer; 113-third copper conductor layer; 12-copper conductor; 20-isolation tape ; 30- insulating layer; 40- outer sheath; A- first circumferential direction; B- second circumferential direction.

detailed description

To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this application, but not all the embodiments. The components of the embodiments of the present application that are generally described and illustrated in the drawings herein can be arranged and designed in various configurations.

Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other if there is no conflict.

It should be noted that similar reference numerals and letters indicate similar items in the following drawings, therefore, once an item is defined in one drawing, there is no need to further define and explain it in subsequent drawings.

In the description of the embodiments of the present application, it should be noted that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that is conventionally placed when the application product is used, or this The orientation or positional relationship commonly understood by those skilled in the art, or the orientation or positional relationship that is usually placed when the product of this application is used, is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must It has a specific orientation and is constructed and operated in a specific orientation, so it cannot be understood as a limitation to the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

Example 1

FIG. 1 is a low-voltage wind energy cable 100 provided by this embodiment. As shown in FIG. 1, the low-voltage wind energy cable 100 in this embodiment includes a conductor 10, an isolation tape 20, an insulating layer 30, and an outer jacket 40; wherein, the isolation tape 20 is wrapped around the outer side of the conductor 10, and the insulating layer 30 is wrapped Outside the isolation tape 20, the outer sheath 40 covers the outside of the insulating layer 30.

In this embodiment, the conductor 10 uses a soft copper wire 12 with a diameter ranging from 0.45 mm to 0.55 mm as the basic constituent unit. In this embodiment, the outer diameter of the soft copper wire 12 forming the tow 11 is the same, The number of soft copper wires 12 included in the tow 11 is also the same, that is, the outer diameter of each tow 11 is the same.

It should be noted that the conductor 10 is formed by twisting twice, that is, a plurality of soft copper wires 12 are stranded along the first circumferential direction A to form a tow 11, and a plurality of copper wires 12 are stranded to form a tow 11 The process is the first stranding, and FIG. 2 is a schematic structural view of the tow 11 shown in FIG. 1; the multi-strand tow 11 is twisted along the second circumferential direction B to form the conductor 10, and the multi-strand tow 11 is stranded to form the conductor 10 This process is the second twisting. In addition, in this embodiment, the first circumferential direction A is opposite to the second circumferential direction B, that is, the first circumferential direction A is counterclockwise and the second circumferential direction B is forward In the direction of the hour hand, the diameter of the conductor 10 finally formed ranges from 1.5 mm to 37.4 mm. In other specific embodiments, the conductor 10 can also be formed in other ways, and does not affect the flexibility and power transmission performance of the conductor 10, for example, the two twists are in the same circumferential direction, that is, the two twists are in the clockwise direction Or twist it counterclockwise.

To form the conductor 10 by twisting, it is necessary to operate according to a certain pitch diameter ratio. The so-called pitch diameter ratio is any single wire of each layer in the stranded wire, which is spirally wound around a center line according to a certain twisting angle. Twisted, a complete spiral pitch in the direction of the twisted wire axis is the pitch length, where the ratio of the pitch length to the outer diameter of the twisted wire is the pitch diameter ratio, and the size of the pitch diameter ratio is related to the tightness of the twisted wire The degree, the weight of the stranded wire and the size of the resistance of the stranded wire are all specified in the product standard of the wire for the ratio of the pitch diameter.

In this embodiment, the pitch ratio of the first stranding and the second stranding is 1: 8, that is, in the first stranding, each soft layer in each layer of the tow 11 The copper wires 12 are all twisted around a center line according to a certain twisting angle, and the ratio of the pitch of a completed spiral in the first circumferential direction A to the outer diameter of the tow 11 is 1: 8; In the second twisting, each strand 11 in each layer of the conductor 10 is twisted in a spiral shape around a central strand 11 according to a certain twisting angle, in the second circumferential direction B The ratio of the pitch of a completed spiral to the outer diameter of the conductor 10 is 1: 8. Choosing a smaller diameter soft copper wire 12 as the basic unit of the conductor 10 and forming the conductor 10 by twisting in two different directions not only can ensure the flexibility and power transmission performance of the conductor 10, but also make the conductor 10 more compact in structure . In addition, the pitch ratio of the two strands is 1: 8, so that the surface of the conductor 10 after the stranding does not have dense unevenness, the outer diameter of the tow 11 and the copper wire 12 are different, the two strands The spiral pitch is also different, to a certain extent, the gap between the spiral pitches can be complemented. In this embodiment, the soft copper wire 12 is annealed, the process is simple, and it is easy to implement. In other specific embodiments, the pitch ratio of the two twists can be used to ensure the flexibility and power transmission performance of the cable. The ratio, and the pitch ratio of the two twists may also be different.

The isolation tape 20 covers the outer side of the conductor 10. In this embodiment, the isolation tape 20 is a reinforced nonwoven fabric isolation tape, and the winding thickness is 0.14 mm. In other specific embodiments, the insulation tape 20 may also be other materials, such as FTC phase change fire insulation material insulation tape.

Since the conductor 10 is formed by twisting a plurality of strands 11 and the strand 11 is formed by twisting a plurality of soft copper wires 12, therefore, between each tow 11 and between each soft copper wire 12 Gap, so that the outer surface of the conductor 10 is not smooth, if the insulating layer 30 is directly coated on the outside of the conductor 10, partial discharge is likely to occur when using the low-voltage wind energy cable 100, by covering the conductor 10 with the non-woven isolation tape 20 Outside, the gap between the tows 11 and the soft copper wires 12 can be reduced, making the structure of the conductor 10 more compact and the power transmission performance better, reducing or even avoiding when the low-voltage wind power cable 100 is in use Partial discharge occurs inside the cable, which improves the safety of the low-voltage wind energy cable 100 in use.

The insulating layer 30 covers the outside of the isolation tape 20. In this embodiment, the insulating layer 30 is made of high-strength flame-retardant ethylene-propylene rubber, and the flame-retardant high-strength ethylene-propylene insulating material is obtained by adding reinforcing agents such as clay to the insulation. Insulation tensile strength reaches 12.3Mpa, which is nearly twice that of ordinary ethylene propylene rubber material (4.2Mpa), making the insulation layer 30 reach VW-1 flame retardant level, and high mechanical properties make the electrical safety performance of the low-voltage wind energy cable 100 get Improve; the cable meets the oil resistance of PRI in UL44 (100 ℃, 96h, retention of tensile strength and elongation at break ≥50%), much higher than the oil resistance index of conventional wind energy cables (100 ℃, 24h, tensile) Change rate of strength and elongation at break ± 40%). It not only meets the use requirements of wind turbines, but also has higher flame retardancy and electrical safety. It extends the service life to a certain extent and reduces the maintenance cost in the later stage.

In addition, in this embodiment, by increasing the temperature of each area of the ethylene propylene rubber, a filter plate is added to the rubber extruder to increase the pressure of the rubber material in the screw barrel, increase the friction, and plasticize the material to ensure the tightness of the insulation layer 30. And symmetry; secondly, after repeated debugging and verification, the distance of the production die is increased by 1.0mm. On the premise of ensuring that no pour phenomenon occurs during the production process, the pressure during the extrusion of the rubber material is fully increased to make the insulating layer 30 more It is tightly coated on the surface of the conductor 10 to avoid the bulging problem of the cable insulation layer 30. Finally, after repeated adjustment of the vulcanization process, the final process conditions are: steam pressure 17Bar, line speed 9m / min, so that the finished insulation can meet the performance It is required to avoid the phenomenon that the hardness of the rubber material is large, the extrusion temperature is high, and the vulcanization temperature is high. It is easy to cause poor plasticization, the surface is not smooth, and the performance of the sulfur is not qualified, and the package is not tight.

The outer sheath 40 covers the outside of the insulating layer 30. The material of the outer sheath 40 is chlorinated polyethylene rubber. In this embodiment, the positive vulcanization time of chlorinated polyethylene rubber is longer than that of the insulating material. The calculation of the vulcanization process is a key step. In this embodiment, the vulcanization process conditions The steam pressure is 17Bar, the water level is controlled at 30%, and the linear velocity is controlled at 9m / min, which ensures that the outer sheath is fully cured and the surface is smooth and smooth. At the same time, in order to further ensure the quality of the surface of the cable, the outer protection extrusion die was chrome-plated to increase the surface finish of the die and prevent the accumulation of coke in the die opening to cause scratches on the surface of the outer sheath 40. The outer sheath 40 has a smooth surface, no scorch, no blistering phenomenon, and has good flame retardant, oil resistance and low temperature resistance properties.

Among them, the insulating layer 30 and the outer sheath 40 are wrapped around the outer side of the isolation belt 20 by double-layer co-extrusion, and the double-layer simultaneous extrusion method can avoid contamination of the inner-layer insulating surface due to two extrusions separately Problems such as damage and damage occur, so that the two adjacent layers of insulation are closely combined to improve the quality of the cable.

In this embodiment, a low-voltage wind energy cable 100 is provided. The cable of this structural design has a wide range of applications, has comprehensive advantages such as power transmission and high mechanical strength, and the cable can be produced only by the existing production equipment of the factory. In addition, the low-voltage wind energy cable 100 uses a soft copper wire 12 with a small diameter as a basic component unit, and forms a conductor 10 of the low-voltage wind energy cable 100 with a reasonable pitch-to-diameter ratio by twisting in opposite directions twice, so that the low voltage The wind energy cable 100 has a compact structure and good flexibility, so that the cable is not easy to break when twisted, which increases the service life of the cable and reduces operating costs. The insulation layer 30 is made of high-strength ethylene-propylene rubber material. Adding clay and other reinforcing agents to obtain flame-retardant high-strength ethylene-propylene insulation materials makes the tensile strength of the ethylene-propylene rubber material much higher than that of ordinary ethylene-propylene rubber materials, which not only meets the needs of wind turbines, but also is flame-retardant and Higher electrical safety, extend its service life to a certain extent, and reduce the later maintenance cost; the material of outer sheath 40 Chlorinated polyethylene rubber that has been vulcanized for a long time is used. The treated chlorinated polyethylene rubber has better flame retardancy, oil resistance, low temperature resistance and ultraviolet resistance than ordinary chlorinated polyethylene rubber. And in order to further ensure the quality of the cable surface, the outer sheath extrusion die was chrome-plated to increase the finish of the mold surface and prevent the accumulation of coke in the die opening to cause scratches on the outer sheath surface to ensure the smooth surface of the outer sheath. No scorch, no blistering phenomenon, the use of flame retardant high-strength ethylene-propylene rubber material and high flame-retardant chlorinated polyethylene rubber material, so that the finished low-voltage wind power cable 100 can pass the flame retardant FT4 test in UL 1685.

Example 2

FIG. 3 is a schematic structural diagram of a low-voltage wind power cable 100 provided by this embodiment. The difference between this embodiment and Embodiment 1 is that the outer diameters of the soft copper wires 12 twisted to form the tow 11 are different.

FIG. 4 is a schematic diagram of the structure of the tow 11 shown in FIG. 3. As shown in FIG. 4, there are soft copper wires 12 with different outer diameters in each tow 11, that is, the tow 11 includes a first copper wire layer 111, a second copper wire layer 112 and a third The copper conductor layer 113, the second copper conductor layer 112 is stranded outside the first copper conductor layer 111, and the third copper conductor layer 113 is stranded outside the second copper conductor layer 112. In this embodiment, the first copper The wire layer 111 is a soft copper wire 12 located in the middle of the tow 11, the second copper wire layer 112 includes a plurality of soft copper wires 12, and the third copper wire layer 113 includes a plurality of soft copper wires 12, wherein the second The outer diameter of the soft copper wire 12 in the copper wire layer 112 is smaller than the outer diameter of the soft copper wire 12 in the first copper wire layer 111 and the outer diameter of the soft copper wire 12 in the third copper wire layer 113. The copper wire 12 with a smaller outer diameter can fill part of the gap in the tow 11 formed by twisting, which makes the tow 11 more compact, reduces the possibility of partial discharge, and improves the power transmission performance of the low-voltage wind energy cable 100 and Safety performance.

In other specific embodiments, the conductor 10 can also be formed by twisting a plurality of strands 11 with different outer diameters. The smaller diameter outer strands 11 can achieve partial gap filling between the strands 11 and can make the conductor 10 structure. It is more compact, reduces the possibility of partial discharge, and improves the power transmission performance and safety performance of the low-voltage wind energy cable 100.

The rest of the structure of the embodiment is the same as that of Embodiment 1, and will not be repeated here.

The above are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of this application shall be included in the scope of protection of this application.

Claims

A low-voltage wind energy cable, characterized in that it includes:

conductor;

Isolation tape, which is wrapped around the outside of the conductor;

An insulating layer, the insulating layer covering the outside of the isolation tape, and the insulating layer material is ethylene-propylene rubber; and

An outer sheath, the outer sheath is wrapped outside the insulating layer;

The conductor includes a plurality of strands, the strands are twisted to form the conductor, and each strand of the strand includes a plurality of copper wires, and the plurality of copper wires are stranded to form each strand of the tow;

The plurality of copper wires are twisted along a first circumferential direction to form the tow, the multiple strands are twisted along a second circumferential direction to form the conductor, and the first circumferential direction and the second circumferential direction in contrast;

The tow includes a first copper wire layer, a second copper wire layer, and a third copper wire layer arranged in order from inside to outside, and the outer diameter of the copper wire in the second copper wire layer is smaller than the first The outer diameter of the copper wire in a copper wire layer and the outer diameter of the copper wire in the third copper wire layer.
The low-voltage wind energy cable according to claim 1, wherein the ratio of the outer diameter of the copper wire to the pitch length of the tow is 1: 8.
The low-voltage wind energy cable according to any one of claims 1-2, wherein the ratio of the outside diameter of the tow to the pitch length of the conductor is 1: 8.
The low-voltage wind energy cable according to claim 1, wherein the diameter of the copper wire is 0.45 mm to 0.55 mm.
The low-voltage wind energy cable according to claim 3, wherein the diameter of the conductor is 1.5 mm to 37.4 mm.
The low-voltage wind energy cable according to claim 1, wherein the outer sheath material is chlorinated polyethylene rubber.
The low-voltage wind energy cable according to claim 1, wherein the insulating layer and the outer sheath are coated on the outside of the conductor by a double-layer co-extrusion method.