EP3958280A1 - Coaxial cable - Google Patents

Abstract

The invention relates to a coaxial cable (1) for the transmission of electrical current in a high-voltage system of a motor vehicle
- an inner conductor (2);
- an outer conductor (4);
- An inner insulation layer (3) arranged between the inner conductor (2) and the outer conductor (4);
- and an insulating cable sheath (7);
wherein the outer conductor (4) is designed to be able to transmit essentially the same electrical power as the inner conductor (2).

In order to enable simplified contacting of the outer conductor (4), the invention provides that the individual wires of the outer conductor (4), seen in a cross-sectional area of the coaxial cable (1) normal to a cable axis (9) of the coaxial cable (1), are divided into at least three sector bundles (5), the sector bundles (5) being dimensioned in such a way that the inner conductor (2) is positioned eccentrically to the cable axis (9) in the cross-sectional area, and the inner conductor (2) and the sector bundles (5) of the outer conductor (4 ) are twisted together.

Description

• einen eine Mehrzahl an Einzeldrähten umfassenden Innenleiter;
• einen eine Mehrzahl an Einzeldrähten umfassenden Außenleiter;
• eine zwischen Innenleiter und Außenleiter angeordnete innere Isolationsschicht;
• sowie einen isolierenden Kabelmantel;

wobei der Außenleiter ausgebildet ist, um zwischen 50% und 150% einer vom Innenleiter übertragbaren elektrischen Leistung übertragen zu können, sowie die Verwendung eines solchen Kabels in einem Hochvoltsystem eines Kraftfahrzeuges mit einem elektrischen Antrieb.The invention relates to a coaxial cable for the transmission of electrical current in a high-voltage system of a motor vehicle

• an inner conductor comprising a plurality of strands;
• an outer conductor comprising a plurality of strands;
• an inner insulating layer arranged between the inner conductor and the outer conductor;
• and an insulating cable jacket;

wherein the outer conductor is designed to be able to transmit between 50% and 150% of an electrical power that can be transmitted by the inner conductor, and the use of such a cable in a high-voltage system of a motor vehicle with an electric drive.

In vehicle technology, high-voltage systems, also referred to as high-voltage or HV for short, are systems which are operated with alternating voltages of over 30 V to 1 kV or with direct voltages of over 60 V to 1.5 kV. Such high-voltage systems are found in particular in vehicles with an electric drive, such as electric vehicles, hybrid vehicles or vehicles with fuel cells.

Coaxial cables are generally understood to mean cables with cable structures in which an inner conductor and at least one outer conductor surrounding the inner conductor in cross section on the outside are provided, with an inner insulating layer electrically insulating the inner conductor from the outer conductor. Furthermore, cables generally also comprise an insulating cable jacket, which preferably represents the outermost layer of the cable, which cable jacket isolates the interior of the cable from the environment and is usually made of a plastic or an elastomer.

STATE OF THE ART

Usually, in high-voltage systems, cables are used for the electrical connection of the electrical components, which cables have two cable cores running parallel to one another. Each cable core has a corresponding first insulation layer, also known as core insulation, with the electrical conductor routed in the core insulation usually being in the form of a stranded wire. The two cable cores are surrounded by an insulating cable sheath, the cable sheath being made of a dielectric material, usually a cross-linked plastic or an elastomer. The cable jacket usually forms the outer insulation layer of the cable. Electrically conductive materials are suitable as the material of the electrical conductor, in particular of the inner conductor, in particular metals such as copper or aluminum or alloys containing these metals.

For example, from the DE 10 2014 010 346 B3 also a direct current line designed as a coaxial cable for a high-voltage vehicle electrical system of a motor vehicle is known, the wire cores of one line arrangement being arranged in a ring shape around the wire cores of the other line arrangement in cross section.

A disadvantage of the cables according to the prior art is that contacting the outer conductor can only be achieved with great effort if the outer conductor is detached from the inner conductor. Furthermore, there are disadvantages, especially with large nominal cross sections, in the dissipation of heat generated in the inner conductor during operation and with regard to the ease with which the cable can be laid.

OBJECT OF THE INVENTION

It is therefore an object of the invention to overcome the disadvantages of the prior art and to propose a coaxial cable which enables simplified contacting of the Outer conductor allows. Furthermore, the properties required for laying the coaxial cable should also be improved and preferably improved heat dissipation from the inner conductor should be achieved. A further object of the invention consists in proposing such a cable structure which can be produced inexpensively and economically.

PRESENTATION OF THE INVENTION

This object is achieved in a coaxial cable according to the invention of the type mentioned at the outset in that the individual wires of the outer conductor, seen in a cross-sectional area of the coaxial cable normal to a cable axis of the coaxial cable, are divided into at least three, preferably at least four, sector bundles, with the sector bundles being dimensioned in this way are that the inner conductor is positioned eccentrically to the cable axis in the cross-sectional area and the inner conductor and the sector bundles of the outer conductor are stranded together.

While in conventional coaxial cables the inner conductor and the ring-shaped outer conductor are arranged coaxially, i.e. the cable axis forms the axis of symmetry of the inner conductor and outer conductor, in the coaxial cable according to the invention the inner conductor is arranged eccentrically to the cable axis, which runs through a center point of the cross section. This eccentric arrangement of the inner conductor is achieved by dividing the individual wires of the outer conductor into at least three separate sector bundles, which are dimensioned such that a conductor axis of the inner conductor arranged inside the sector bundle is offset relative to the cable axis. Such a dimensioning according to the invention can be achieved, for example, by varying the number of individual wires and/or the number of layers of the individual wires in the radial direction and/or the diameter of the individual wires of the sector bundles. These are preferably of different sizes for at least three sector bundles. If several layers of individual wires are provided in a sector bundle, the number of individual wires per layer can also vary. Depending on the relative position of a sector bundle in relation to the cross section and the total number of sector bundles, different sector bundles can also be constructed in the same way.

It goes without saying that the individual wires of the inner conductor and/or the outer conductor can also be in the form of stranded wires. For example, the sector bundles can consist of strands, which in turn each comprise a plurality of individual wires.

In other words, the sector bundles are designed in such a way that they take up different proportions of the cross-sectional area of the outer conductor. For example, a sector bundle running in the area of the smallest distance between the inner conductor and cable sheath can take up the smallest proportion of the cross-sectional area in terms of area, while a sector bundle running in the area of the greatest distance between the inner conductor and cable jacket can take up the largest proportion of the cross-sectional area in terms of area.

Preferably, an outer surface of the inner insulation layer of the inner conductor is in contact with the inner surfaces of the sector bundles, that is to say with the surfaces of the sector bundles that are on the inside in the radial direction. Correspondingly, the design of the inner surfaces of the sector bundles can be used to dimension the sector bundles for producing the eccentricity.

A coaxial cable with an eccentric inner conductor is particularly easy to produce if the insulated inner conductor is stranded with the sector bundles. In other words, the sector bundles are wound around the insulated inner conductor using a stranding machine and/or corresponding components of a stranding system, with the stranding also moving the center of the eccentric inner conductor in relation to the cable axis on a helical path. In other words, the position of the inner conductor changes relative to the cable axis as viewed in cross-section cutting plane to cutting plane. A further embodiment variant of the invention therefore provides that the inner conductor and the sector bundles of the outer conductor are stranded together.

Due to the eccentric course of the inner conductor, a particularly simple detachment of the outer conductor can be achieved in an end area of the coaxial cable freed from the cable sheath, since the outer conductor can be divided in the area of that sector bundle which runs in the area of a maximum eccentric deflection of the inner conductor and thus the lowest resistance having. The detached outer conductor can then be bundled, for example, in a stranded connection section.

In addition, due to the eccentricity of the inner conductor, easier heat dissipation from the inner conductor can be ensured.

Finally, the direction-dependent bending resistance can be reduced by the eccentric course of the inner conductor and the use of sector bundles as the outer conductor, so that easier laying can be achieved.

Another positive effect of the coaxial cable is that additional electromagnetic shielding is not absolutely necessary, especially if one of the conductors is designed as a positive conductor and the other conductor as a negative conductor of a DC HV system.

A further embodiment of the coaxial cable according to the invention provides that the number and/or the diameter of the individual wires of any sector bundle is different from the number and/or the diameters of the individual wires of a sector bundle adjoining any sector bundle. In principle, it is also conceivable that the number of layers of the individual wires is different, with it, in particular for the purposes of Manufacturing has proven to be advantageous when the number of layers is the same. The eccentricity of the inner conductor can be adjusted particularly easily due to the different number of individual wires and/or the different diameters of the individual wires in adjacent sector bundles. For example, a sector bundle running in the area of the smallest distance between the inner conductor and the cable sheath can comprise a larger number of individual wires with smaller diameters than the radially adjoining sector bundle.

Provision is particularly preferably made for the number of individual wires and the diameter of the individual wires of the sector bundles to be selected as a function of the position of the respective sector bundle relative to the eccentricity of the inner conductor.

Advantageously, the number of sector bundles is even, preferably four, six, eight or ten, with more sector bundles also being possible, depending on the diameter of the coaxial cable. This enables a simpler geometric design of the cross-section of the coaxial cable. The stranding of the inner conductor and sector bundle can also be accomplished more easily if the number of sector bundles is even. A further embodiment variant of the invention therefore provides that the number of sector bundles is even and the individual wires of the outer conductor are divided into at least four, preferably at least six or at least eight, sector bundles. A preferred embodiment of the invention provides that exactly four sector bundles are provided.

In a further embodiment variant of the invention, for simple and reliable production of the eccentricity, it is provided that the sector bundles are designed as pairs of sector bundles that lie opposite one another within the cross-sectional area and correspond to one another, with a nominal cross-section of any pair of sector bundles between 25% and 175%, preferably between 50 and 150%, in particular between 75% and 125% of an average nominal cross-section of all pairs of sector bundles. The nominal cross-section of a sector bundle is understood to be the sum of the cross-sectional areas of the individual wires of the sector bundle, while the nominal cross-section of the pair of sector bundles corresponds to the sum of the nominal cross-sections of the two sector bundles. The average nominal cross section of all pairs of sector bundles can be calculated as the arithmetic, geometric or harmonic mean of the nominal cross sections of all pairs of sector bundles.

Regardless of the preferred size ratios of the sector bundle pairs to one another, it is advantageous if the sector bundles are divided into mutually complementary sector bundle pairs in order to be able to set the eccentricity of the inner conductor by dimensioning opposite sector bundles of a sector bundle pair.

While the design of the inner surfaces of the sector bundles is decisive for the eccentric positioning of the inner conductor within the outer conductor, the outer surfaces of the sector bundles are decisive for the outer shape of the outer conductor. In order to bring the enveloping surface of the outer conductor as close as possible to a cylinder, which is advantageous or necessary, for example, for extruding the cable sheath, the sector bundles are dimensioned in a further embodiment such that an enveloping surface of the outer conductor essentially corresponds to a cylinder with a circular cross-sectional area. Analogous to the dimensioning of the sector bundles for the eccentric positioning of the inner conductor, this dimensioning can be achieved by varying the number of individual wires per sector bundle and/or the number of layers of the individual wires in the radial direction per sector bundle and/or the diameter of the individual wires of a sector bundle . The previously mentioned cylindrical shape of the enveloping surface is preferably achieved by appropriate dimensioning of the sector bundles in combination with the stranding.

In order to ensure greater flexibility and bendability of the coaxial cable both with small nominal cross sections and with large nominal cross sections, another variant provides that the individual wires of the sector bundles are arranged in one or more layers depending on a nominal cross section of the outer conductor. For example, the sector bundles are designed in one layer for small nominal cross sections and in multiple layers for larger nominal cross sections.

A further embodiment variant of the invention provides that a cable foil or a metal foil or a composite foil is arranged between the outer conductor and the cable sheath. While a metal foil, for example an aluminum foil, and/or a composite foil can also improve the electromagnetic shielding properties of the coaxial cable, a cable foil, in particular made of plastic, can contribute to easier production and/or removal of the cable jacket on or from the outer conductor.

A high degree of optical coverage of the outer conductor is advantageous in particular for the electromagnetic shielding properties of the outer conductor and possibly for the most precise possible approximation of the cylindrical enveloping surface. A further embodiment variant of the coaxial cable according to the invention therefore provides that the degree of coverage of the outer conductor is greater than 90%, preferably greater than 95%.

In the area of high-voltage systems, a particularly high temperature resistance of the cables used is advantageous. In order to achieve the application-specific temperature resistance, a further embodiment provides that the cable jacket and/or the inner insulation layer is made from a thermoplastic and/or cross-linked plastic or an elastomer or from a silicone. Silicone is understood to mean silicone-containing plastics, in particular from the group of poly(organo)siloxanes.

In order to ensure that the two conductors, i.e. inner conductor and outer conductor, of the coaxial cable can be connected to the same power source at one end and to the same current collector at the other end, one embodiment of the invention provides that the outer conductor is designed in such a way that it is the same can transmit electrical power like the inner conductor.

In connection with the electrical power to be transmitted by the inner conductor, it should be noted that charging stations for vehicles with an electric drive, such as electric cars, require an electrical power of up to 350 kW, which when connecting the vehicle with an electric drive to the charging station in the High-voltage system of the vehicle must be transmitted. Of course, it is also conceivable that smaller electrical powers are also transmitted during operation or the charging process, or that the high-voltage system as a whole is designed for larger or smaller maximum powers.

The power transmission from the inner conductor and outer conductor can be matched to one another in a particularly simple manner by design measures, in particular if the conductors are made of the same materials, if a nominal cross section of the helical conductor is between 75% and 125%, preferably between 90% and 110%, in particular 100% of a nominal cross section of the inner conductor. The nominal cross section of the inner conductor is advantageously between 3 mm ² and 95 mm ² , in particular between 6 mm ² and 60 mm ² .

In order to be able to connect the outer conductor to a current source and/or a current collector and/or a connecting element in a simple manner, as mentioned at the beginning, a further embodiment variant provides that when the coaxial cable is in contact, in an end region of the Coaxial cable the outer conductor is detached from the inner conductor and the detached individual wires of the outer conductor in the form of a stranded Connecting section are bundled. In a simple process step, the detached individual wires of the outer conductor can be bundled as a stranded wire in a connecting section. The stranded connection section can then be connected to an electrical connection like a conventional conductor, which enables the coaxial cable according to the invention to be used easily in conventional high-voltage systems. Of course, it is also conceivable that a corresponding contacting device is provided as an alternative, by means of which the coaxial cable can be contacted without first detaching the outer conductor.

The eccentric course of the inner conductor enables the outer conductor to be detached from the inner conductor in a particularly simple manner, since the locally smaller thickness of the outer conductor can be utilized. A further embodiment variant of the invention therefore provides that the outer conductor is divided in the contact state in order to produce the stranded connection section in the area of a maximum eccentric deflection of the inner conductor. As a result, the effort required for the deformation and detachment is particularly low.

As mentioned at the outset, the coaxial cable according to the invention is intended for use in a high-voltage system of a motor vehicle. Motor vehicles in which high-voltage systems are present are characterized by an electric drive, which is designed either as an alternative to an internal combustion engine in a hybrid vehicle or as the sole drive in an electric vehicle. Due to the improved flexibility compared to alternative design variants and the improved properties of the coaxial cable according to the invention, such a coaxial cable is particularly well suited for use in a high-voltage system of a motor vehicle with an electric drive.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be explained in more detail using exemplary embodiments. The drawings are exemplary and are intended to explain the idea of the invention, but in no way restrict or even conclusively reproduce it.

Fig. 1

eine axonometrische Ansicht eines ersten Ausführungsbeispiels eines abschnittsweise freigelegten Koaxialkabels;

Fig. 2

eine Seitenansicht des Koaxialkabels nach Fig. 1;

Fig. 3

einen vergrößerten Querschnitt des Koaxialkabels nach Fig. 1;

Fig. 4

eine axonometrische Ansicht eines zweiten Ausführungsbeispiels eines abschnittsweise freigelegten Koaxialkabels;

Fig. 5

einen vergrößerten Querschnitt des Koaxialkabels nach Fig. 4;

Fig. 6

eine schematische Darstellung eines Koaxialkabels in einem Kontaktzustand.

It shows:

1

an axonometric view of a first embodiment of a partially exposed coaxial cable;

2

a side view of the coaxial cable 1 ;

3

an enlarged cross-section of the coaxial cable 1 ;

4

an axonometric view of a second embodiment of a partially exposed coaxial cable;

figure 5

an enlarged cross-section of the coaxial cable 4 ;

6

a schematic representation of a coaxial cable in a contact state.

WAYS TO CARRY OUT THE INVENTION

the Figures 1 to 3 show the structure of a first embodiment and the Figures 4 to 5 the structure of a first exemplary embodiment of a coaxial cable 1 according to the invention for use in a high-voltage system of a motor vehicle for the transmission of electrical current. As a rule, corresponding coaxial cables 1 are used to connect power sources, for example rechargeable batteries, to current collectors, such as electric drive units, in particular electric motors. The nominal cross-sections of the conductors 2.4 of the cable 1 are chosen accordingly in order to be able to transmit the currents and voltages of the high-voltage system. For the sake of clarity, the individual areas of the coaxial cable are exposed.

In the Figures 1 and 2 it can be seen that the coaxial cable 1 comprises an inner conductor 2 comprising a plurality of individual wires, which is insulated from the outer conductor 4 surrounding it by means of an inner insulation layer 3 . The outer conductor also comprises a number of individual wires which are divided into different sector bundles 5 in order to achieve an eccentric course of the inner conductor 2, as will be described in detail below. The coaxial cable 1 also includes an outer insulating cable jacket 7 made of plastic, which is preferably designed as silicone insulation. In addition, a foil 8, preferably a metal foil, in particular an aluminum foil, is provided between the outer conductor 4 and the cable sheath 7, which improves the properties of the coaxial cable 1, but is not necessary for the basic structure.

The detailed structure of the coaxial cable 1 is now based on the figure 3 discussed. As can be clearly seen, the inner conductor 2 is positioned eccentrically with respect to the cable axis 9 in the illustrated cross section, which is aligned normal to a cable axis 9 of the coaxial cable. In other words, there is an offset between the cable axis 9 and a conductor axis 6 of the inner conductor 2.

This offset of conductor axis 6 and cable axis 9 is achieved in that the sector bundles 5 are dimensioned in such a way that the inner conductor 2 is positioned eccentrically to the cable axis 9 in the cross-sectional area. In detail, the outer conductor 4 in the present exemplary embodiment is divided into four sector bundles 5, namely a first sector bundle 5a, which runs in the area of the greatest distance between the inner conductor 2 and the cable sheath 7, a third sector bundle 5c, which runs in the area of the smallest distance between the inner conductor 2 and Cable sheath 7 runs and a second sector bundle 5b and a fourth sector bundle 5d, which are each arranged to run between the first sector bundle 5a and the third sector bundle 5c.

By appropriately dimensioning the different sector bundles 5, i.e. by selecting the number of individual wires per sector bundle 5 and the diameter of the individual wires per sector bundle 5, the eccentric offset of the inner conductor 2 can be adjusted, with the individual wires of the sector bundle 5 being designed to run in a single layer in the present exemplary embodiment .

In detail, in the present exemplary embodiment, the diameter of the individual wires of the first sector bundle 5a is greater than the diameter of the individual wires of the adjacent second sector bundle 5b or the adjacent fourth sector bundle 5d. Looking at the third sector bundle 5c, the number of individual wires in the adjacent sector bundles 5b, 5d is smaller and the diameter of the individual wires in the adjacent sector bundles 5b, 5d is larger than that of the third sector bundle 5c.

When examining the cross section, it also emerges that the first sector bundle 5a and the third sector bundle 5c or the second sector bundle 5b and the fourth sector bundle 5d each form a pair of sector bundles, since the respective sector bundles 5 relate to each other in cross section with respect to the cable axis 9 on the one hand are opposite and on the other hand complement each other in order to determine the position of the inner conductor 2.

How out figure 3 As can be seen, the design of the surfaces of the sector bundles 5 facing the inner conductor 2 is decisive for the eccentric positioning of the inner conductor 2 . In order to additionally ensure that an enveloping surface of the outer conductor 4 essentially corresponds to a cylinder with a circular cross-sectional area, which is particularly advantageous or necessary for the application of the cable sheath 7, the individual wires of the sector bundles 5 are also dimensioned or designed in such a way that the the outer surfaces of the sector bundles 5 facing the cable sheath 7 have this property.

In the present exemplary embodiment, the sector bundles 5 of the outer conductor 4 are stranded with the inner conductor 2. As a result of the stranding process, the position of the inner conductor 2 in cross-section relative to the cable axis 9 also changes from sectional plane to sectional plane. In other words, the eccentric inner conductor 2 runs in the form of a helical surface around the cable axis 9. This "wobbling movement" of the inner conductor 2 is, for example, figure 2 particularly recognizable.

the figures 4 and 5 show a second embodiment of the coaxial cable 1, which has a larger nominal cross-section than the coaxial cable 1 according to the first embodiment. The basic structure of the second exemplary embodiment is analogous to the structure previously described, so that only the differences are discussed.

While the individual wires of the sector bundles 5 of the first exemplary embodiment are arranged in a single layer, the individual wires of the sector bundles 5 of the second exemplary embodiment are arranged in multiple layers, more precisely in two layers. This means that the diameter of the individual wires can be kept smaller in comparison to a single-layer design, in order to increase the flexibility of the coaxial cable 1 .

It goes without saying that more than four sector bundles 5 can also be provided with the same operating principle, for example six or eight or more. Equally, in this case, correspondingly more mutually complementary pairs of sector bundles would also be provided.

In figure 6 an advantageous design of an end region 10 of a coaxial cable 1 is shown in a contact state, which simplifies the connection of the coaxial cable 1 according to the invention to an electrical connection. At least the cable jacket 7 has been removed in the end region 10 of the cable 1, so that the outer conductor 4 is exposed. The fact that the outer conductor 4 is wound helically around the inner conductor 2, that is is stranded, the individual wires of the outer conductor 4 can be detached from the inner conductor 2 in a simple manner. After the individual wires of the outer conductor 4 have been detached, the individual wires of the outer conductor 4 are brought together on one side of the inner conductor 2 and bundled in a stranded connection section 11 .

By bundling the individual wires of the outer conductor 4 in the stranded connection section 11, the end area of the cable 1 corresponds to a cable with two stranded cable connection sections for connection with the inner insulation layers 3 in the end section of the end area 10 and the inner conductor 2 is thus stripped an electrical connection, the stripped end section of the inner conductor 2 representing a first cable connection section and the stranded connection section 11 of the outer conductor 4 representing a second cable connection section.

It is particularly advantageous if, in order to detach the outer conductor 4, that sector bundle 5 that runs in the area of a maximum eccentric deflection of the inner conductor 2 is divided. In the two exemplary embodiments, the outer conductor would therefore be divided in the area of the third sector bundle 5c.

In this way, the coaxial cable 1 can be connected in a simple manner to another electrical component, for example to a power source or to a current collector. This is because in the area of the stranded connection section 11, which represents the end section of the outer conductor 4, the individual wires of the outer conductor 4 are converted into a stranded conductor and bundled, which stranded connection section 11 can then be connected to the electrical component in a conventional manner. Since the inner conductor 2 and the stranded connection section 11 of the helical conductor 4 can thus be connected separately and possibly also differently can be arranged running to one another, there is no longer a significant difference in the contact state to the connection of a conventional two-wire cable due to the provision of the stranded connecting section 11 in the coaxial cable 1 according to the invention. In other words, the coaxial cable 1 according to the invention also has two stranded cable connection sections in the contact state, which essentially correspond to the end section of a conventional two-wire cable.

For the reasons mentioned above, the cable 1 according to the invention is particularly suitable for use in high-voltage systems of motor vehicles with an electric drive, since it is designed in particular for the transmission of current between a current source and a current collector, with the inner conductor 2 being the positive pole of the current source in a direct current system, for example connects to the power consumer while the helical conductor 4 connects the negative pole of the power source to the power consumer, although of course the reverse assignment of the conductors is also conceivable.

REFERENCE LIST

1

coaxial cable

2

inner conductor
2a bundle of inner conductors

3

inner insulation layer

4

outer conductor

5

sector bundle
5a first sector bundle
5b second sector bundle
5c third sector bundle
5d fourth sector bundle

6

conductor axis

7

cable jacket

8th

foil

9

cable axis

10

end section

11

stranded connecting section

Claims (14)

Comprising a coaxial cable (1) for the transmission of electrical current in a high-voltage system of a motor vehicle - An inner conductor (2) comprising a plurality of individual wires; - An outer conductor (4) comprising a plurality of individual wires; - An inner insulation layer (3) arranged between the inner conductor (2) and the outer conductor (4); - and an insulating cable sheath (7); wherein the outer conductor (4) is designed to be able to transmit between 50% and 150%, preferably between 75% and 125%, particularly preferably 100% +/- 5%, of an electrical power that can be transmitted by the inner conductor (2),
characterized in that
the individual wires of the outer conductor (4), seen in a cross-sectional area of the coaxial cable (1) normal to a cable axis (9) of the coaxial cable (1), are divided into at least three sector bundles (5), the sector bundles (5) being dimensioned in such a way, that the inner conductor (2) is positioned eccentrically to the cable axis (9) in the cross-sectional area,
and wherein the inner conductor (2) and the sector bundles (5) of the outer conductor (4) are stranded together. Coaxial cable (1) according to Claim 1, characterized in that the number and/or the diameter of the individual wires of any sector bundle (5, 5a) is different in size to the number and/or the diameter of the individual wires of one connected to any sector bundle (5, 5a) adjacent sector bundle (5,5b,5d). Coaxial cable (1) according to any one of claims 1 to 2, characterized in that the number of sector bundles is straight and the individual wires of the outer conductor are divided into at least four, preferably at least six or at least eight sector bundles. Coaxial cable (1) according to Claim 3, characterized in that the sector bundles (5) are designed as pairs of sector bundles (5a, 5c; 5b, 5d) which lie opposite one another within the cross-sectional area and correspond to one another, with a nominal cross-section of any pair of sector bundles ( 5a, 5c; 5b, 5d) is between 25% and 175%, preferably between 50% and 150%, in particular between 75% and 125%, of an average nominal cross section of all sector bundle pairs (5a, 5c; 5b, 5d). Coaxial cable (1) according to one of Claims 1 to 4, characterized in that the sector bundles (5) are dimensioned in such a way that an enveloping surface of the outer conductor (4) essentially corresponds to a cylinder with a circular cross-sectional area. Coaxial cable (1) according to one of Claims 1 to 5, characterized in that the individual wires of the sector bundles (5) are arranged in one or more layers depending on a nominal cross section of the outer conductor (4). Coaxial cable (1) according to one of Claims 1 to 6, characterized in that a foil (8), preferably a cable foil or a metal foil or a composite foil, is arranged between the outer conductor (4) and the cable sheath (7). Coaxial cable (1) according to one of Claims 1 to 7, characterized in that a degree of coverage of the outer conductor (4) is greater than 90%, preferably greater than 95%. Coaxial cable (1) according to one of Claims 1 to 8, characterized in that the cable jacket (7) and/or the inner insulation layer (3) is made from a thermoplastic and/or crosslinked plastic or an elastomer or from a silicone. Coaxial cable (1) according to one of Claims 1 to 9, characterized in that the outer conductor (4) is designed in such a way that it can transmit the same electrical power as the inner conductor (1). Coaxial cable (1) according to one of Claims 1 to 10, characterized in that a nominal cross section of the outer conductor (4) is between 75% and 125%, preferably between 90% and 110%, in particular 100%, of a nominal cross section of the inner conductor (2). . Coaxial cable (1) according to one of Claims 1 to 11, characterized in that when the coaxial cable (1) is in contact, the outer conductor (4) separates from the inner conductor (2nd ) is detached and the detached individual wires of the outer conductor (4) are bundled in the form of a stranded connecting section (11). Coaxial cable (1) according to Claim 12, characterized in that the outer conductor (4) is divided in the contact state for producing the stranded connection section (11) in the area of a maximum eccentric deflection of the inner conductor (2). Use of a coaxial cable (1) according to one of Claims 1 to 13 in a high-voltage system of a motor vehicle with an electric drive.

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