Electric line arrangement

Abstract

An electric line arrangement, in particular a charging cable for a motor vehicle, having at least one electrically conductive lead which can be placed in electrical contact at its ends in order to transmit electrical energy, an insulation layer which surrounds the lead circumferentially, and a coolant duct in which a cooling fluid for cooling the lead is conducted, wherein the insulation layer is spaced apart from the lead, and the coolant duct is formed between the insulation layer and the lead in such a way that the cooling fluid flows directly around the lead.

Claims

1. A charging cable for a motor vehicle, comprising: at least one electrically conductive lead which can be placed in electrical contact at its ends in order to transmit electrical energy, an insulation layer which surrounds the lead circumferentially, a first coolant duct In which a cooling fluid for cooling the lead can be conducted, wherein the insulation layer is spaced apart from the lead, and the first coolant duct is formed between the insulation layer and the lead in such a way that the cooling fluid flows directly around the lead, a sheathed layer which surrounds the insulation layer circumferentially, wherein the sheathed layer is spaced apart from the insulation layer, a second coolant duct formed between the sheathed layer and the insulation layer, and a plug-type connector, at an axial end of the charging cable, in electrical contact with the at least one electrically conductive lead, and wherein the plug-type connector connects the first coolant duct to the second coolant duct.

2. The charging cable as claimed in claim 1, wherein a cavity, which forms the first coolant duct, is formed between the insulation layer and the lead.

3. The charging cable as claimed in claim 1, wherein the first coolant duct forms a coolant forward flow line, and the second coolant duct forms a coolant return flow line.

4. The charging cable as claimed in claim 1, wherein the plug-type connector has an opening which is connected to the first coolant duct in order to discharge the cooling fluid from the electric line arrangement.

5. The charging cable as claimed in claim 1, wherein the plug-type connector is configured to be connected to a coolant arrangement in order to feed the cooling fluid to the first coolant duct.

6. The charging cable as claimed in claim 1, wherein the electric line arrangement has a pressure sensor which is arranged in the second coolant duct in order to detect a pressure drop in the second coolant duct.

7. The charging cable as claimed in claim 6, wherein a second pressure sensor is arranged in the first coolant duct in order to determine a position of damage to the first coolant duct.

8. The charging cable of claim 1, further comprising a second plug-type connector in order to connect the electric charging cable to the motor vehicle or to a charging station.

9. The charging cable of claim 1, wherein the insulation layer is a solid tube.

10. A charging cable for a motor vehicle, comprising: at least one electrically conductive lead which can he placed in electrical contact at its ends in order to transmit electrical energy, an insulation layer which surrounds the lead circumferentially, a first coolant duct in which a cooling fluid for cooling the lead, can be conducted, wherein the insulation layer is spaced apart from the lead, and the first coolant duct is formed between the insulation layer and the lead in such a way that the cooling fluid flows directly around the lead, and a plug-type connector, at an axial end of the charging cable, in electrical contact with the at least one electrically conductive lead, wherein the plug-type connector is configured to be connected to a coolant arrangement in order to feed the cooling fluid to the first coolant duct.

11. A charging cable for a motor vehicle, comprising: two electrically conductive leads, each electrically conductive lead having axial ends lying opposite one another and each axial end being connected to an electric connection in order to place the respective electrically conductive lead in electrical contact at the axial ends to a charging station and the motor vehicle and, in order to transmit electrical energy to an electric energy store of the motor vehicle, wherein the two electrically conductive leads form different poles of the charging cable, a first insulation layer which surrounds a first lead of the two electrically conductive leads circumferentially and is spaced apart from the first lead, a second insulation layer which surrounds a second lead, of the two electrically conductive leads circumferentially and is spaced apart from the second lead, a first coolant duct in which a cooling fluid for cooling the first lead of the two electrically conductive leads can be conducted, wherein the first coolant duct is formed between the first insulation layer and the first lead such that the cooling fluid flows directly around the first lead, a second coolant duct in which a cooling fluid for cooling the second lead of the two electrically conductive leads can be conducted, wherein the second coolant duct is formed between the second insulation layer and the second lead such that the cooling fluid flows directly around the second lead, and a circulating cooling system for the two electrically conductive leads which can be supplied with cooling medium from the charging station.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) Exemplary embodiments of the invention are illustrated in the drawing and will be explained in more detail in the following description, in which:

(2) FIG. 1 shows a schematic illustration of an electric line arrangement which, as a charging cable, connects an electrically driven motor vehicle electrically to a charging station;

(3) FIG. 2 shows a schematic cross-sectional view of a first embodiment of the electric line arrangement with a coolant duct;

(4) FIG. 3 shows a schematic cross-sectional view of a second embodiment of the electric line arrangement with two coolant ducts; and

(5) FIG. 4 shows a schematic view of a longitudinal section of the electric line arrangement according to a second embodiment from FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION

(6) In FIG. 1, an electric line arrangement is illustrated schematically and is denoted generally by 10. The electric line arrangement 10 forms a charging cable for a motor vehicle 12 and connects the motor vehicle 12 to a charging station 14 in order to charge an electric energy store of the motor vehicle 12 correspondingly at the charging station 14.

(7) The electric line arrangement 10 generally has an electrically conductive lead 16 which is connected at each of its axial ends lying opposite one another to an electric connection 18, 20 or a plug 18, 20 or plug-type connector 18, 20, in order to connect the electrically conductive lead 16 electrically to the charge station 14 or the motor vehicle 12 and correspondingly to transmit electrical energy to the electric energy store of the motor vehicle 12. The electric line arrangement 10 also has an insulation layer 22 which surrounds the electrically conductive lead 16 circumferentially and correspondingly insulates it electrically from the surroundings. The insulation layer 22 is spaced apart from the electrically conductive lead 16, with the result that a cavity is formed between the electrically conductive lead 16 and the insulation layer 22. The cavity forms a coolant duct 24 in which a cooling fluid for cooling the electrically conductive lead 16 is or can be conducted. The electrically conductive lead 16 does not have any electrically insulating cladding, with the result that the cooling fluid in the coolant duct 24 directly flows around the electrically conductive lead 16 or directly touches the current-conducting conductors of the lead 16 and correspondingly a directly convective transfer of heat is formed between the cooling fluid and the electric lead 16.

(8) As a result of the fact that the cooling fluid is formed in the cavity between the insulation layer 22 and the electrically conductive lead 16, the technical expenditure on making available the coolant duct 24 can be considerably reduced and at the same time the discharging of the waste heat of the electrically conductive lead 16 can be considerably improved.

(9) The electrically conductive lead 16 is connected at each of its axial ends to the respective electric connection 18, 20 or to the plug-type connector 18, 20 in order to connect the electric line arrangement 10 correspondingly to the charging station 14 and to the motor vehicle 12.

(10) The cooling fluid, which in one preferred embodiment is formed by ambient air in a cooled or uncooled state, is preferably made available to the cooling duct 24 by the charging station 14 and can be discharged at the plug 20 through an opening or can be fed back to the charging station 14 via a second coolant duct (not illustrated here), as is explained in more detail below.

(11) A schematic sectional view of the electric line arrangement 10 according to a first embodiment is illustrated in FIG. 2.

(12) The electric line arrangement 10 has the lead 16 which is formed from a multiplicity of electrically conductive conductors, preferably metal or copper conductors. The insulation layer 22 surrounds the lead 16 circumferentially and is spaced apart from the lead 16, with the result that a cavity 26 is formed in the radial direction between the lead 16 and the insulation layer 22. The cooling medium 28 which flows around the lead 16 and in this way forms a convective transfer of heat between the lead 16 and the cooling medium 28 is conducted in the cavity 26. The lead 16 is not insulated with respect to the cooling medium, with the result that the cooling medium 28 flows directly around the metallic conductors or the copper conductors. As a result, particularly good transfer of heat can be formed between the lead 16 and the cooling medium 28, with the result that effective cooling of the lead 16 is possible.

(13) The cooling medium 28 can be formed from cooled or uncooled ambient air or can be embodied as circulating cooling fluid.

(14) FIG. 3 illustrates an embodiment of the electric line arrangement 10 in a cross section. Identical elements are denoted by identical reference symbols, wherein only the particular features are explained here.

(15) The electric line arrangement 10 has two leads 16, each with an insulation layer 22, said leads 16 being routed in parallel to one another and forming different leads or different poles of the electric line arrangement 10. The insulation layers 22 of the two leads 16 are surrounded circumferentially by a sheathed layer 30 which forms an outer sleeve of the electric line arrangement 10. The sheathed layer 30 is spaced apart from the insulation layers 22 of the leads 16, with the result that a second cavity 32 is formed between the sheathed layer 30 and the insulation layers 22.

(16) In this arrangement, the first cavities 28 between the insulation layers 22 and the respective leads 16 form a forward flow line for the cooling medium 28, and the second cavity 32 forms a return flow line for the cooling medium 28, as illustrated in FIG. 3. The cavities 26 between the insulation layers 22 and the respective leads 16 are both connected to one of the plugs 18, 20 at an axial end, with the result that the cooling medium 28 can be pumped through the cavities 26, 32. As a result, a circulating cooling system for the leads 16 can be implemented, which cooling system can be supplied with cooling medium from one side such as, for example, the charging station 14.

(17) FIG. 4 illustrates a schematic sectional view of the electric line arrangement 10 in a longitudinal section. Identical elements are denoted by identical reference symbols, wherein only the particular features are explained here.

(18) The electric line arrangement 10 has, within the sheathed layer 30, the lead 16 which is surrounded by the insulation layer 22, wherein the cooling medium 28 is conducted as a forward flow line in the cavity 26, and wherein the cooling medium 28 is conducted as a return flow line in the second cavity 32 between the sheathed layer 30 and the insulation layer 22. The electric line arrangement 10 is connected to the plug-type connector 20 in which a forward flow tap 34 is arranged, which tap is connected to the cavity 26 in order to conduct the cooling medium 28 out of the cavity 26 and introduce it into the second cavity 32 between the insulation layer 22 and the sheathed layer 30. As a result, the cavity 26 can be connected as a forward flow line to the second cavity 32 as a return flow line, and the cooling medium 28 can be correspondingly pumped around in the electric line arrangement 10. As a result, cooled cooling medium 28 can flow around the lead or leads 16, and correspondingly absorb the heat and be fed back via the second cavity 32.

(19) In addition, an electric contact 36 for the lead 16 is formed in the plug 20, in order to connect the electric line arrangement 10 electrically to the motor vehicle 12 or the charging station 14.

(20) In one alternative embodiment, the plug 20 can have an opening through which the cooling medium is conducted out of the cavity 26 and correspondingly disposed of. In this context, it is particularly preferred if the cooling medium 28 is formed by ambient air, with the result that the lead 16 is cooled by sucked-in ambient air, and the heated cooling air is correspondingly discharged again into the surroundings through the opening in the plug 20. As a result, cooling is possible with particularly low technical expenditure.

(21) In one preferred embodiment, the charging station 14 has a coolant arrangement which makes available the cooling medium 28 and introduces it into the cavity 26 and, if appropriate, absorbs the fed-back cooling medium again and feeds it back again in a cooled state to the cavity 26. As a result, effective cooling of the leads 16 is possible by pumping around the cooling medium 28.

(22) In one preferred embodiment, a pressure sensor is arranged in each case in the cavity 26 and the cavity 32, in order to measure a pressure in the cooling system, and to detect a leak in the insulation layer 22 or the sheathed layer 30. If a pressure difference is detected between the pressure sensors 36, 38, a leakage can be identified in the insulation layer 22 or the sheathed layer 30, and the location of said leakage can be determined.