CN216817871U

CN216817871U - Environment-friendly aluminum alloy variable frequency cable for subway

Info

Publication number: CN216817871U
Application number: CN202220615523.7U
Authority: CN
Inventors: 黄勇昌; 樊聪; 王怡晴; 胡高耸; 田间; 李红彬; 杨志辉; 赵静
Original assignee: HENAN LESHAN CABLE CO LTD
Current assignee: HENAN LESHAN CABLE CO LTD
Priority date: 2022-03-21
Filing date: 2022-03-21
Publication date: 2022-06-24
Anticipated expiration: 2032-03-21

Abstract

The utility model discloses an environment-friendly aluminum alloy variable frequency cable for subways, which relates to the field of cables and comprises an outer sheath, N main wire cable cores and N ground wire cable cores, wherein the N main wire cable cores are arranged in the outer sheath in a surrounding manner along the axis of an inner hole of the outer sheath, the N ground wire cable cores are arranged in an outer ring of the N main wire cable cores in a surrounding manner, the outer sheath comprises a low-voltage halogen-free wrapping tape layer, and an inner sheath layer formed by low-smoke halogen-free polyolefin sheath materials is wrapped outside the low-voltage halogen-free wrapping tape layer. The protective device has good protection effect on the variable frequency electric appliance, and reduces the electromagnetic radiation in the whole system.

Description

Environment-friendly aluminum alloy variable frequency cable for subway

Technical Field

The utility model belongs to the field of cables, and particularly relates to an environment-friendly aluminum alloy variable frequency cable for subways.

Background

In recent years, variable frequency speed regulating motors have been developed greatly at home and abroad, the annual growth rate is slightly over 10%, and the annual growth rate of direct current transmission is 3-4%. The variable frequency motor has the advantages of less equipment investment cost, simple structure, small volume, low cost, energy conservation, large speed regulation range, constant power and constant rotating speed, convenient use, large capacity and the like.

Therefore, it is widely used in industries such as metallurgy, mine, railway, and the like, and recently, it is also widely used in household appliances. The variable frequency speed regulation technology relates to a variable frequency motor, a variable frequency power supply and a connecting cable, the length of the cable is not very long, the section of the cable is not very large, and the insulation performance belongs to the category of power cables, because the actual working frequency is 30-300 Hz, the cable is often referred to as the variable frequency cable for short, and currently, crosslinked polyethylene is often selected as an insulation material.

Roughly thirty years ago, a cable research institute develops and produces an intermediate frequency cable, which can be called a precursor of the existing variable frequency cable, the working frequency of the cable is 100-400 Hz, equipment for providing power is an intermediate frequency generator set driven by a direct current motor, the rotating speed of the direct current motor is changed to adjust the output frequency of a generator, the waveform of intermediate frequency voltage can maintain a sine wave with a regular shape, the design idea of the cable is to reduce line impedance and skin effect, the coaxial cable is adopted and the diameter of an inner conductor is enlarged, and the application effect of the cable in the metallurgical industry is very good.

The existing variable frequency power supply is frequency-modulated by a silicon controlled element, and the waveform characteristic is changed to a large extent, so that new problems are brought to a motor and a cable, and a certain optimization space is provided in the aspects of anti-interference performance and electromagnetic shielding performance.

Therefore, we propose an environment-friendly aluminum alloy variable frequency cable for subways to solve the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model provides an environment-friendly aluminum alloy variable frequency cable for subways, which aims to solve the problems that the existing variable frequency power supply is subjected to frequency modulation through a silicon controlled element, the waveform characteristic is changed to a large extent, a new problem is brought to a motor and a cable, and the problem that the cable has certain optimized space in anti-interference performance and electromagnetic shielding performance is solved.

The technical scheme adopted by the utility model for solving the technical problems is as follows: an environment-friendly aluminum alloy variable frequency cable for subways comprises an outer sheath, N main wire cable cores and N ground wire cable cores, wherein the N main wire cable cores are arranged in the outer sheath in a surrounding mode along the axis of an inner hole of the outer sheath, and the N ground wire cable cores are arranged in an outer ring of the N main wire cable cores in a surrounding mode.

The outer sheath comprises a low-voltage halogen-free wrapping tape layer, an inner sheath layer formed by low-smoke halogen-free polyolefin sheath materials wraps the low-voltage halogen-free wrapping tape layer, an armor layer wraps the inner sheath layer, and an outer sheath layer formed by the low-smoke halogen-free polyolefin sheath materials wraps the armor layer.

And a halogen-free low-smoke filling rope is filled among the low-voltage halogen-free belting layer, the ground wire cable core and the main wire cable core to form a filling layer.

The diameter of the ground wire cable core is smaller than that of the main wire cable core, the ground wire cable core and the main wire cable core are of the same structure and respectively comprise a conductor, an insulating layer formed by crosslinked polyethylene insulating materials wraps the conductor, and an insulating shielding layer formed by wrapping a soft copper strip wraps the insulating layer.

As a preferred technical scheme of the utility model, the thickness of the soft copper strip is 0.1 mm.

As a preferable technical scheme of the utility model, the armor layer is formed by buckling an aluminum alloy strip S-shaped interlocking armor and rings.

As a preferable technical scheme of the utility model, the conductor is formed by twisting aluminum alloy wires.

As a preferred technical scheme of the utility model, the number of the main wire cable cores and the ground wire cable cores is three.

As a preferred technical scheme of the utility model, a heat insulation baffle table is arranged at a gap between the ground wire cable core and the two main wire cable cores, and heat dissipation holes are formed in the heat insulation baffle table.

Compared with the prior art, the utility model has the beneficial effects that:

1. according to the utility model, the three main wire cable cores and the three ground wire cable cores are symmetrically cabled, and the symmetrical cable structure has better electromagnetic compatibility due to the interchangeability of the conducting wires, plays a certain role in inhibiting electromagnetic interference, can counteract odd frequencies in higher harmonics, improves the anti-interference performance of the special cable for the variable frequency motor, enables the cable to have stronger voltage impact resistance, can bear pulse voltage during high-speed frequent frequency conversion, plays a good protection role on a variable frequency electric appliance, and reduces the electromagnetic radiation in the whole system.

2. The aluminum alloy cable is adopted to replace the copper cable, so that the weight of the cable can be reduced, the installation cost can be reduced, the abrasion of equipment and the cable can be reduced, and the installation work is easier.

3. According to the utility model, the armor layer is arranged, the interlocking armor adopted by the armor layer has good impact resistance, and the flexibility and bending performance of the cable are good, so that the requirement of 7 times of bending radius can be met; and the aluminum alloy interlocking armor replaces steel tape armor, so that the weight of the cable is greatly reduced.

4. According to the utility model, the thermal insulation blocking platform is arranged, so that the direct contact between the main wire cable core and the ground wire cable core is avoided, the heat transfer between the main wire cable core and the ground wire cable core is avoided, and the heat dissipation effect of the cable is improved.

Drawings

Fig. 1 is a schematic perspective view of the present invention.

In the figure: the cable comprises a conductor 1, an insulating layer 2, an insulating shielding layer 3, a filling layer 4, a low-voltage halogen-free belting layer 5, an inner protection layer 6, an armor layer 7, an outer protection layer 8, a heat insulation blocking platform 9 and heat dissipation holes 10.

Detailed Description

The utility model is further illustrated with reference to the following figures and examples.

Referring to fig. 1, the present invention provides a technical solution of an environment-friendly aluminum alloy variable frequency cable for subways:

the first embodiment is as follows:

according to the figure 1, the cable comprises an outer sheath, three main wire cable cores and three ground wire cable cores, wherein the three main wire cable cores are arranged in the outer sheath in a surrounding mode along the axis of an inner hole of the outer sheath, the three ground wire cable cores are arranged in an outer ring of the three main wire cable cores in a surrounding mode, the three main wire cable cores and the three ground wire cable cores are symmetrically cabled, and the symmetrical cable structure has better electromagnetic compatibility due to the interchangeability of wires, plays a certain role in inhibiting electromagnetic interference, can offset odd-order frequency in higher-order harmonics, improves the anti-interference performance of a special cable for a variable frequency motor, enables the cable to have stronger voltage impact resistance, can bear pulse voltage during high-speed and frequent frequency conversion, plays a good role in protecting a variable frequency electrical appliance, and reduces electromagnetic radiation in the whole system.

The outer sheath comprises a low-voltage halogen-free wrapping tape layer 5, an inner sheath layer 6 formed by low-smoke halogen-free polyolefin sheath materials wraps the low-voltage halogen-free wrapping tape layer 5, an armor layer 7 wraps the inner sheath layer 6, the armor layer 7 is formed by aluminum alloy tapes in an S-shaped interlocking armor mode, and the rings are buckled with one another, through the arrangement of the armor layer 7, the armor layer 7 has good impact resistance by adopting interlocking armor, and the flexibility and the bending performance of the cable are good and can meet the requirement of 7 times of bending radius; the aluminum alloy interlocking armor replaces steel tape armor, the weight of the cable is greatly reduced, and an outer protective layer 8 formed by low-smoke halogen-free polyolefin sheathing material wraps the armor layer 7.

And a halogen-free low-smoke filling rope is filled among the low-voltage halogen-free belting layer 5, the ground wire cable core and the main wire cable core to form a filling layer 4.

The diameter of the ground wire cable core is smaller than that of the main wire cable core, the ground wire cable core and the main wire cable core are of the same structure and comprise conductors 1, the conductors 1 are formed by drawing aluminum alloy wires through an aluminum alloy large wire drawing machine by using an aluminum alloy rod with the diameter of 9.5mm, and then stranding the aluminum alloy wires by using a stranding machine, the actual weight of aluminum alloy is about one third of that of copper under the same volume, so that the weight of the aluminum alloy cable is about half of that of the copper cable under the same current-carrying capacity, the aluminum alloy cable is used for replacing the copper cable, the weight of the cable can be reduced, the installation cost is reduced, the abrasion of equipment and the cable is reduced, the installation work is easier, the conductors 1 are wrapped with an insulating layer 2 formed by crosslinked polyethylene insulating material, the insulating layer 2 is wrapped with an insulating shielding layer 3 formed by wrapping a soft copper strip, and the thickness of the soft copper strip is 0.1 mm.

Example two:

on the basis of the first embodiment, as shown in fig. 1, a thermal insulation baffle 9 is disposed at a gap between the ground wire cable core and the two main wire cable cores, a heat dissipation hole 10 is formed in the thermal insulation baffle 9, and by disposing the thermal insulation baffle 9, the main wire cable core and the ground wire cable core are prevented from being in direct contact with each other, heat transfer between the main wire cable core and the ground wire cable core is avoided, and the heat dissipation effect of the cable is improved.

Example three:

on the basis of the first embodiment, the aluminum alloy wire for the aluminum alloy conductor comprises: the density is 2.710kg/dm³(ii) a Coefficient of linear expansion of 23.0X10^-6(1/. degree. C.); the DC resistivity at 20 ℃ is less than or equal to 0.028264 omega mm²M (more than or equal to 61.0% IACS); mechanical properties of the aluminum alloy wire: tensile strength: 98-159 MPa; the elongation is more than or equal to 10 percent.

Mechanical properties of the aluminum alloy strip: the tensile strength is 60-100N/mm 2, and the elongation at break is more than or equal to 23%.

Low-smoke halogen-free polyolefin sheathThe material performance index is as follows: density: less than or equal to 1.55g/cm³(ii) a Mechanical properties before aging: tensile strength is more than or equal to 10.0N/mm²The elongation at break is more than or equal to 160 percent; the oxygen index is more than or equal to 32 percent; acidity of combustion gas: the pH value is more than or equal to 4.3, and the conductivity is less than or equal to 10 mu s/mm; smoke density: the flame is less than or equal to 350 percent and the flameless is less than or equal to 100 percent; the content of acidic Hcl and HBr in the combustion release gas is less than or equal to 0.5 percent; the dielectric strength is more than or equal to 18.0 MV/m; volume resistivity at 20 deg.C is not less than 1.0 × 10¹⁰Ω·m。

Claims

1. The utility model provides an aluminum alloy variable frequency cable is used to environment-friendly subway, includes oversheath, a N thread cable core and a N ground wire cable core, and a N thread cable core encircles along oversheath hole axle center and sets up in the oversheath, and a N ground wire cable core encircles the outer loop that sets up at a N thread cable core, its characterized in that: the outer sheath comprises a low-voltage halogen-free wrapping tape layer, an inner protection layer formed by low-smoke halogen-free polyolefin sheath materials wraps the low-voltage halogen-free wrapping tape layer, an armor layer wraps the inner protection layer, and an outer protection layer formed by low-smoke halogen-free polyolefin sheath materials wraps the armor layer;

a halogen-free low-smoke filling rope is filled among the low-voltage halogen-free belting layer, the ground wire cable core and the main wire cable core to form a filling layer;

2. The environment-friendly aluminum alloy variable frequency cable for subways according to claim 1, which is characterized in that: the thickness of the soft copper strip is 0.1 mm.

3. The environment-friendly aluminum alloy variable frequency cable for subways according to claim 1, which is characterized in that: the armor layer is formed by mutually buckling S-shaped interlocking armor of aluminum alloy belts and rings.

4. The environment-friendly aluminum alloy variable frequency cable for subways according to claim 1, which is characterized in that: the conductor is formed by twisting aluminum alloy wires.

5. The environment-friendly aluminum alloy variable frequency cable for subways according to any one of claims 1 to 4, wherein: the number of the main wire cable cores and the number of the ground wire cable cores are three.

6. The environment-friendly aluminum alloy variable frequency cable for subways according to claim 5, wherein: and a heat insulation blocking platform is arranged at the gap between the ground wire cable core and the two main wire cable cores, and heat dissipation holes are formed in the heat insulation blocking platform.