WO2011012150A1

WO2011012150A1 - Conductor and cable

Info

Publication number: WO2011012150A1
Application number: PCT/EP2009/005700
Authority: WO
Inventors: Ivanka ATANASOVA-HÖHLEIN; Vladyslav Mezhvynskiy; Ronald Schmid; Andreas Steiner
Original assignee: Siemens Aktiengesellschaft
Priority date: 2009-07-29
Filing date: 2009-07-29
Publication date: 2011-02-03

Abstract

The invention relates, inter alia, to an electrically conductive conductor (10). The invention provides for the conductor to have, in at least one conductor section, nanoparticles (420, 510) that are conductive or increase the conductivity of the conductor, wherein the density of the nanoparticles decreases at least in sections towards the conductor edge.

Description

Description Conductor and cable The invention relates to an electrically conductive conductor.

Such conductors are used for example in the field of electrical energy transmission technology and can be contained for example in cables.

The invention has for its object to provide a conductor having better electrical properties than previous conductors.

This object is achieved according to the invention by a conductor having the features according to claim 1. Advantageous embodiments of the conductor according to the invention are specified in sub-claims.

Thereafter, it is provided that the conductor m has conductive particles or nanoparticles which increase the conductivity of the conductor at least one conductor section, the density of the nanoparticles dropping at least in sections towards the conductor edge.

An essential advantage of the conductor according to the invention is the fact that a very favorable conductivity distribution within the conductor can be achieved by the nanoparticle distribution provided according to the invention, that is to say by the drop in density to the conductor edge. Thus, inside the conductor, a greater conductivity than outside can be achieved, whereby the skin effect is reduced in the case of operation of the conductor with alternating current. The current density of the Ladder is thus - compared to conventional ladders - inside larger and the current distribution with it - viewed in the middle over the conductor cross-section - uniform. The skine effect typical current concentration at the conductor edge is thus avoided, or at least significantly reduced.

A further significant advantage of the conductor according to the invention is the improved heat distribution in the conductor cross-section, since the heat generation due to the higher nanoparticle density in the interior and concomitantly by the lower electrical resistance in the interior - compared to the edge region, at which a heat removal is easier - reduced becomes. A third significant advantage of the conductor according to the invention is the fact that in this case the mechanical strength of the conductor is markedly increased by the nanoparticles present therein. The inventive conductor is therefore mechanically significantly stronger and more resilient than comparable conductors of prior art design without nanoparticles with the same dimensions and weight. Due to the increased mechanical strength and load capacity can be achieved with the inventive conductor thus significantly larger span widths between masts and support elements, as is possible with previous conductors. The use of the inventive conductor in electrical energy transmission systems thus leads to lower installation costs.

As already mentioned, the density of the nanoparticles in the interior, ie for example in the middle of the conductor, is preferably greater than at the edge of the conductor.

According to a particularly preferred embodiment of the conductor is provided that the conductor is an electrically conductive Conductor core having a predetermined first concentration of nanodisks and that the conductor has at least one electrically conductive layer surrounding the conductor core, whose electrical conductivity and its concentration of nanoparticles are smaller than those of the conductor core.

Alternatively, it can be provided that the density of the nanoparticles steadily decreases in at least one section of the conductor towards the conductor edge or has a step-shaped course.

Preferably, the concentration in the interior of the conductor is at least locally, for example centrally, at least twice as large as at the conductor edge.

By way of example, the conductor can be rotationally symmetrical and have a rotationally symmetrical nanoparticle concentration profile which radially drops off in at least one profile section towards the conductor edge. Alternatively, the core may consist of a foil.

Preferably, at least the conductor core consists of a metal-containing, in particular copper-containing, material, particularly preferably of a metal-containing material with nanoparticles contained therein.

The conductor edge may, for example, have a surface into which nanoparticles have been introduced or incorporated thermally and / or physically from the outside.

Most preferably, the nanoparticles are elongated. It is considered advantageous if, in the majority of the nanoparticles, the longitudinal direction of the nanoparticles is aligned parallel to the conductor longitudinal direction, in order to reduce the conductivity of the conductor to increase in the longitudinal direction. By elongated nanotubes are meant nanoparticles whose length is greater than their diameter. Elongated nanoparticles are, for example, nanotubes, nanotubes or nanorods. The nanoparticles can be single-walled, double-walled or multi-walled. The nanoparticles may, for example, be carbon nanotubes or carbon nanoneedles or boron nitride nanoparticles. The invention also relates to a cable with a conductor as described above. The conductor is preferably covered with an insulating material.

The insulating material may for example consist of a coating layer, a polymer and / or paper or at least one of the materials mentioned at least have.

The invention also relates to a method for producing a conductor. According to the invention, provision is made for nanoparticles to be arranged in the conductor in such a way that the density of the nanoparticles drops at least in sections toward the edge of the conductor. With regard to the advantages of the method according to the invention, reference is made to the above statements in connection with the inventive conductor, since the advantages of the inventive conductor essentially correspond to those of the method according to the invention.

According to a preferred embodiment of the method, it is provided that an electrically conductive conductor core is produced with a predetermined first concentration of nanoparticles and at least one electrically conductive layer around the Core core is produced, wherein the layer has a lower electrical conductivity and concentration of nanoparticles than the conductor core. Nanoparticles, for example, can be introduced or incorporated into the surface of the conductor thermally and / or physically from the outside.

Also, the conductor can be wrapped with an insulating material.

The invention will be explained in more detail with reference to exemplary embodiments; 1 shows in cross section a first exemplary embodiment of a conductor according to the invention, which can be used in an electrical cable,

FIG. 2 shows in cross-section a second exemplary embodiment of a conductor according to the invention with a multi-stage nanoparticle distribution,

FIG. 3 shows in cross-section a third exemplary embodiment of a conductor according to the invention with a continuous distribution of the nanoparticles, with the nanoparticle density dropping towards the conductor edge,

FIG. 4 shows in cross-section a fourth exemplary embodiment of a conductor according to the invention with a nanoparticle-free conductor core which is formed by a carrier foil,

5 shows in cross section a fifth exemplary embodiment of a conductor according to the invention with a nanoparticle containing conductor core, which is formed by a carrier foil,

FIG. 6 a cross-section of an exemplary embodiment of a cable according to the invention with a conductor which is provided on the edge side with an insulation layer,

FIG. 7 shows an exemplary embodiment of a method for producing a nanoparticle-containing surface on a conductor,

Figure 8 shows a second exemplary embodiment of a method for producing a nanoparticulate surface and

Figure 9 in cross section a further exemplary embodiment of a conductor according to the invention.

For the sake of clarity, the same reference numbers are always used in the figures for identical or comparable components.

In the figure 1, an electrically conductive conductor 10 is shown in cross section, in the middle of which an electrically conductive conductor core 20 is located. The conductor core extends in a radius range between r = 0 and r = rl.

The electrically conductive conductor core 20 is surrounded by an electrically conductive layer 30, which extends in the radial direction in a range between r = rl and r = r2. The electrical conductor core 20 and the electrically conductive layer 30 are preferably rotationally symmetrical Both the electrically conductive conductor core 20 and the electrically conductive layer 30 are equipped with nanoparticles whose density depends on the radius. Thus, it can be seen in FIG. 1 that the density N (r) of the nanoparticles depends on the radial distance r from the conductor center.

The conductor core 20 has a nanoparticle density NI, which may be, for example, 10% or more. The nanoparticle density in the electroconductive layer 30 is smaller than the concentration Nl and has a concentration value N2 of, for example, only 5 percent or less.

The concentration distribution N (r) or the concentration profile N (r) is discontinuous in the exemplary embodiment according to FIG. 1, since there is a density jump at the position r = rl.

FIG. 1 also shows the electrical conductivity σ (r) of the conductor 10. It can be seen that a conductivity jump occurs in the region of the radius r = rl. For example, the electrical conductivity σ (r) in the conductor core 20 has a conductivity value σ 1 which exceeds the electrical conductivity value σ 2 in the conductive layer 30. At the location r = r1, in addition to the nanoparticle density jump already mentioned, a conductivity jump occurs as well. The conductivity distribution in the conductor 10 is accordingly also unsteady. The conductivity profile σ (r) in the conductor 10 corresponds to the

Course forth the concentration distribution of the nanoparticles, since the nanoparticles contribute significantly to the electrical conductivity of the conductor 10: So the conductivity is in the conductor As a rule, this is greatest where the highest nanoparticle density occurs, and the conductivity is lower where the nanoparticle concentration is smaller. The nanoparticles are preferably nanotubes or nanotubes, particularly preferably carbon nanotubes, the longitudinal direction of which - at least predominantly - is oriented parallel to the conductor longitudinal direction. Due to the described alignment parallel to the conductor longitudinal direction, a particularly high electrical conductivity is achieved by the nanoparticles.

FIG. 2 shows a second exemplary embodiment of an electrical conductor 10. In contrast to the exemplary embodiment according to FIG. 1, in the conductor according to FIG. 2 the conductor core 20 is enveloped by a plurality of electrically conductive layers 30, 31 and 32.

The three layers 30, 31 and 32 differ with regard to the concentration of nanoparticles and, concomitantly, in the respective electrical conductivity of the nanoparticles

Layer. Thus, it can be seen in FIG. 2 that the density of the nanoparticles in the conductor core 20 assumes the greatest value. For larger radii r, ie toward the conductor edge of the conductor 10, the concentration of the nanoparticles decreases in stages or in steps. This shows in Figure 2, the concentration profile or the concentration distribution, which is represented by the reference numeral N (r) over the radius r.

In addition, FIG. 2 shows the conductivity profile σ (r) in the electrical conductor 10. It can be seen that, due to the described distribution of the nanoparticles, in particular due to the drop in the nanoparticle density. te to the conductor edge, the electrical conductivity decreases to the conductor edge. Accordingly, the profile of the electrical conductivity is also step-shaped and falls off in a stepped manner towards the edge of the conductor.

FIG. 3 shows a third exemplary embodiment of an electrical conductor 10. In contrast to the two exemplary embodiments according to FIGS. 1 and 2, in this conductor the concentration profile or the concentration distribution N (r) of the nanoparticles is continuous and decreases steadily from the conductor center (r = 0) to the conductor edge (r = rl). The density of the nanoparticles has the value Nl in the center of the conductor and the value N2 at the conductor edge of the conductor. Particularly preferred is:

Nl> 2 * N2

FIG. 4 shows a fourth exemplary embodiment of a conductor 10. In this conductor, the electrically conductive conductor core 20 is formed by a carrier foil 100. A carrier foil 100 is understood to mean a carrier whose thickness d is much smaller than its width b (d <b / 10). The carrier foil consists for example of copper without nanoparticles.

The carrier film 100 is in an electrically conductive

Embedded layer 30, which is applied for example by means of an electrolysis or electroplated on the carrier sheet 100. The conductive layer 30 is provided with nanoparticles to achieve a given conductivity profile in the conductor 10.

The distribution of the nanoparticles along the y-direction is also shown in FIG. One recognizes that the Density of the nanoparticles in the conductive layer 30 drops towards the edge. Accordingly, the electrical conductivity in the interior of the conductive layer 30 is greater than at the outer edge of the conductive layer 30. The distribution of the nanoparticles along the x-direction is corresponding.

FIG. 5 shows a fifth exemplary embodiment of a conductor 10. In this conductor, the electrically conductive conductor core 20 is formed by a carrier foil 200, which is embedded in an electrically conductive layer 30.

Both the carrier foil 200 and the conductive layer 30 are provided with nanoparticles in order to achieve a predetermined conductivity profile in the conductor 10. The distribution of the nanoparticles along the y-direction is also shown in FIG. It can be seen that the density of the nanoparticles in the conductive layer 30 drops towards the edge. Accordingly, the electrical conductivity in the interior of the conductive layer 30 is greater than at the outer edge of the conductive layer 30. In the carrier film, the density of the nanoparticles and thus the conductivity is greatest. The distribution of the nanoparticles along the x direction is corresponding. FIG. 6 shows an exemplary embodiment of a cable 300. The cable 300 has an electrically conductive conductor 10, which is equipped with an electrically conductive conductor core 20 and an electrically conductive layer 30. The conductor 10 can, for example, correspond to the conductor of FIG. 1 or, alternatively, be formed by a conductor 10 whose conductor core has no nanoparticles. The nanoparticle-containing layer 30 of the conductor 10 is preferably applied galvanically. An insulating layer 310 is arranged around the electrical conductor 10, which insulates the electrical conductor 10 towards the outside. The insulation layer can consist, for example, of an insulation material such as lacquer, polymer and / or paper. The insulating layer 110 may therefore also be, for example, a lacquer layer.

Reference will now be made, by way of example, to illustrate briefly how a nanoparticle-containing conductor surface can be produced. Thus, in FIG. 7, a strand-shaped conductor 400 can be seen, on the surface 410 of which nanoparticles 420 are introduced or introduced. Such deposition or incorporation may be effected thermally, for example using suitable composites, and / or physically. The conductor 400 correspondingly coated with the nanoparticles 420 is shown by the reference numeral 430 in the figure. The metal lattice structure of the conductor preferably remains unchanged in the nanoparticle coating. FIG. 8 visualizes, by way of example, how a flat or foil-like conductor (foil conductor) 500 can be provided with nanoparticles in order to form a nanoparticle-containing surface. The nanoparticles are identified by the reference numeral 510 in FIG. If the nanoparticles 510, which are present, for example, in powder form prior to processing, are introduced thermally, for example using suitable composites, and / or physically into the surface 520 of the conductor 500, the result is an electrical conductor 530 with a nanoparticle-containing surface. The metal lattice structure of the conductor preferably remains unchanged in the nanoparticle coating.

FIG. 9 shows a further exemplary embodiment of an electrical conductor 10. Unlike the export According to FIG. 2, in the conductor according to FIG. 9 the conductor core 20 is nanoparticle-free. The conductor core 20 preferably consists of a conductive material such as copper, as can be seen in FIG. 9 on the basis of the relatively high conductivity in the core, or alternatively of a non-metal, for example of a non-conductor or semiconductor material.

Otherwise, the statements on FIG. 2 apply correspondingly in terms of content.

reference numeral

10 conductors

20 conductor core

30,31,32 layer

100 carrier film

200 carrier foil

300 cables

310 insulation layer

400 conductors

410 surface

420 nanoparticles

430 coated conductor

500 conductors

510 nanoparticles

520 surface

530 conductor d thickness

b width

N (r) density

r radius

σ (r) electrical conductivity

Claims

claims

1. electrically conductive conductor (10),

d a d u r c h e c e n c i n e s that

the conductor has conductive nanoparticles (420, 510) in at least one conductor section or increases the conductivity of the conductor,

wherein the density of the nanoparticles drops towards the edge of the guide at least in sections.

2. Head according to one of the preceding claims,

d a d u r c h e c e n c i n e s that

the density of nanoparticles inside the conductor is greater than at the edge of the conductor.

3. Head according to one of the preceding claims,

characterized,

that the conductor has an electrically conductive conductor core (20) with a predetermined concentration of nanoparticles, and

the conductor has at least one electrically conductive layer (30) surrounding the conductor core, whose electrical conductivity and its concentration of nanoparticles are smaller than those of the conductor core.

4. Head according to one of the preceding claims,

d a d u r c h e c e n c i n e s that

the concentration inside the conductor is at least locally at least twice as large as at the conductor edge.

5. Ladder according to one of the preceding claims,

d a d u r c h e c e n c i n e s that

at least the conductor core consists of a metal-containing, in particular copper-containing, material.

6. A conductor according to one of the preceding claims, characterized in that

the conductor core consists of a foil.

7. Ladder according to one of the preceding claims,

d a d u r c h e c e n c i n e s that

the conductor edge has a surface into which nanoparticles have been introduced or incorporated thermally and / or physically from the outside.

8. Ladder according to one of the preceding claims,

d a d u r c h e c e n c i n e s that

the nanoparticles are nanotubes or nanotubes.

9. cable (300) having a conductor (10) according to any one of the preceding claims.

10. Cable according to claim 9,

d a d u r c h e c e n c i n e s that

the conductor is covered with an insulating material.

11. Cable according to claim 10,

d a d u r c h e c e n c i n e s that

the insulating material consists of a lacquer layer, a polymer and / or paper or at least one of the said materials at least also has.

12. A method for producing a conductor (10),

d a d u r c h e c e n c i n e s that

Nanoparticles are arranged in the conductor such that the density of the nanoparticles towards the conductor edge drops at least in sections.

13. The method according to claim 12,

d a d u r c h e c e n c i n e s that

an electrically conductive conductor core (20) is produced with a predetermined concentration of nanoparticles, and

at least one electrically conductive layer (30) is produced around the conductor core, wherein the layer has a lower electrical conductivity and concentration of nanoparticles than the conductor core.

14. The method according to claim 12 or 13,

d a d u r c h e c e n c i n e s that

nanoparticles can be introduced or incorporated into the surface of the conductor thermally and / or physically from the outside.

15. The method according to any one of the preceding claims 12-14, d a d u r c h e c e n e z e c h e n e, that

the conductor is wrapped with an insulating material.