CHARGING CABLE FOR CHARGING AN ELECTRIC VEHICLE, AND ELECTRIC VEHICLE SUPPLY EQUIPMENT WITH A CHARGING CABLE

Abstract

The disclosure relates to a charging cable for charging an electric vehicle, wherein the charging cable includes a coolant supply tube extending in a longitudinal direction and configured for transporting a coolant through the charging cable, an earth extending in a longitudinal direction substantially parallel to the coolant supply tube and configured for serving as ground, a plurality of power wires extending in the longitudinal direction and configured for conducting positive and/or negative direct current, and an outer layer extending in the longitudinal direction and surrounding the coolant supply tube, the earth and the plurality of power wires, wherein each of the plurality of power wires includes a power conductor and a power wire insulation surrounding the power conductor, wherein multiple spacers are provided between the power conductor and the power wire insulation such that a coolant channel is defined between the power conductor and the power wire insulation.

Claims

1. A charging cable for charging an electric vehicle, wherein the charging cable comprises: a coolant supply tube extending in a longitudinal direction and configured for transporting a coolant through the charging cable; an earth extending in a longitudinal direction substantially parallel to the coolant supply tube and configured for serving as ground; a plurality of power wires extending in the longitudinal direction and configured for conducting positive and/or negative direct current; and an outer mantle extending in the longitudinal direction and surrounding the coolant supply tube, the earth and the plurality of power wires, wherein each of the plurality of power wires comprises a power conductor and a power wire insulation surrounding the power conductor, wherein multiple spacers are provided between the power conductor and the power wire insulation such that a coolant channel is defined between the power conductor and the power wire insulation.

2. The charging cable according to claim 1, wherein the multiple spacers comprise beads that are arranged between the power conductor and the power wire insulation, wherein the beads are provided parallel to the power conductor or are spiraling around the power conductor.

3. The charging cable according to claim 1, wherein the power wire insulation has an inner surface, and wherein the spacers comprise protrusions that are provided at the inner surface of the power wire insulation.

4. The charging cable according to claim 3, wherein the protrusions are triangular protrusions, each having a base and an apex, wherein the base is facing towards the inner surface of the power wire insulation, and the apex is facing towards the power conductor.

5. The charging cable according to claim 1, wherein a coolant is provided within the coolant channel and/or the coolant supply tube.

6. The charging cable according to claim 5, wherein the coolant is an ultrapure water/glycol mixture.

7. The charging cable according to claim 1, wherein the power conductors of each of the power wires is substantially wedge-shaped.

8. The charging cable according to claim 1, wherein the power conductor of each of the power wires has a diameter of about 8 mm, wherein the power wire insulation has an inner diameter of about 12 mm, wherein the power wire insulation has an outer diameter of about 15 mm, wherein the power wire insulation has a wall thickness of about 1.5 mm, wherein the charging cable has a length of about 5.5 m, wherein the power conductor of each of the power wires has a cross-section of about 50 mm.sup.2, and/or wherein the coolant supply tube has a diameter of about 10 mm.

9. The charging cable according to claim 1, wherein the earth is provided around the coolant supply tube.

10. The charging cable according to claim 1, wherein the coolant supply tube is arranged in the middle of the charging cable.

11. The charging cable according to claim 1, wherein the power conductor of each of the power wires is manufactured from a material selected from a group comprising aluminum and copper.

12. The charging cable according to claim 1, wherein the charging cable is rated for 1000 A.

13. A electric vehicle supply equipment, EVSE, for charging an electric vehicle, comprising a charging cable according to claim 1, a charging connector configured for being connected to the electric vehicle, and a cooling unit, wherein the charging cable is provided between the cooling unit and the charging connector, the cooling unit is configured for transporting coolant towards the charging connector through the coolant supply tube, and the charging connector is configured for returning the coolant towards the cooling unit through the coolant channel of each power wire.

14. The electric vehicle supply equipment according to claim 13, wherein the coolant is an ultrapure water/glycol mixture.

15. A method for liquid-cooling a charging cable for charging an electric vehicle, wherein the charging cable comprises: a coolant supply tube extending in a longitudinal direction and configured for transporting a coolant through the charging cable; an earth extending in a longitudinal direction substantially parallel to the coolant supply tube and configured for serving as ground; a plurality of power wires extending in the longitudinal direction and configured for conducting positive and/or negative direct current; and an outer mantle extending in the longitudinal direction and surrounding the coolant supply tube, the earth and the plurality of power wires, wherein each of the plurality of power wires comprises a power conductor and a power wire insulation surrounding the power conductor, wherein multiple spacers are provided between the power conductor and the power wire insulation such that a coolant channel is defined between the power conductor and the power wire insulation, wherein the method comprises: transporting coolant through a coolant supply channel and the coolant channel of each of the plurality of power wires.

16. The charging cable according to claim 3, wherein the power wire insulation and the spacers are manufactured integrally.

17. The charging cable according to claim 12, wherein the charging cable is rated for 2000 A.

18. The charging cable according to claim 12, wherein the charging cable is rated for 3000 A.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The disclosure will be elucidated on the basis of an exemplary embodiment shown in the attached drawings, in which:

[0030] FIG. 1 shows a sectional view of a power wire of a charging cable according to an embodiment of the disclosure;

[0031] FIG. 2 shows a sectional view of a power wire of a charging cable according to an alternative embodiment of the disclosure;

[0032] FIG. 3 shows a sectional view of a charging cable with the power wire of FIG. 2 according to an embodiment of the disclosure; and

[0033] FIG. 4 shows a schematic view of an electric vehicle supply equipment according to an embodiment of the disclosure.

DETAILED DESCRIPTION

[0034] A charging cable 1 according to the disclosure is provided with a plurality of power wires 2. Such a charging cable 1 may be used for transferring a direct current, DC, from a charge post, to which the charging cable 1 is connected at one end thereof, to a charging connector, which is provided at the charging cable 1 at another end thereof. A sectional view of a power wire 2 of a charging cable 1 according to an embodiment of the disclosure is shown in FIG. 1. The power wire 2 includes a power conductor 3 for conducting a negative DC or a positive DC through the power wire 2. The power conductor 3 is manufactured from copper and has a diameter of about 8 mm, which results in a cross-section of about 50 mm.sup.2.

[0035] A power wire insulation 4 is provided around the power conductor 3, such that the power wire insulation 4 surrounds the power conductor 3 in order to prevent the power conductor 3 from coming into contact with another not shown power conductor of an adjacent power wire 2. The power wire insulation 4 is manufactured from an electrically insulating material. As shown in FIG. 1, the power wire insulation 4 has a substantially cylindrical shape and has an inner diameter D1 of about 12 mm and an outer diameter D2 of about 15 mm. The wall thickness of the power wire insulation 4, therefore, is about 1.5 mm. Since the inner diameter D1 of the power wire insulation 5 is larger than the diameter of the power wire 3, a coolant space 5, also called coolant channel, is defined between the power conductor 3 and the power wire insulation 4. A coolant, such as ultrapure water/glycol may flow and/or be forced through the coolant space 5 in order to cool the power conductor 3.

[0036] As shown in FIG. 1, three spacers 6 are arranged within the coolant space 5, which spacers are evenly distributed around the power conductor 3. The spacers 6 are provided for centering the power conductor 3 within the power wire insulation 4. Each of the spacers 6 includes a bead 7 that runs substantially parallel to the power conductor 3 or, optionally, is spiraling around the power conductor 3. There is no need for the beads 7 to spiral around the power conductor 3, as long as the beads 7 stay in place.

[0037] Alternatively, as shown in FIG. 2, the spacers 6 include triangular protrusions 8 extending from the inner surface of the power wire insulation 4 into the coolant space 5 and towards the power conductor 3, thereby contacting the power conductor 3. Each of the triangular protrusions 8 has a basis 9, which is directed towards the inner surface of the power wire insulation 4, and an apex 10, which is directed towards and in contact with the power conductor 3. By directing the apices 10 of the triangular protrusions 8 towards the power conductor 3, a contact surface area of the power conductor 3, which is the part thereof that is not covered by the triangular protrusions 8, is kept as large as possible. The triangular protrusions 8 and the power wire insulation 4 may be manufactured by extruding.

[0038] A charging cable 1, according to an embodiment of the disclosure, with a power wire 2 as shown in FIG. 2 is shown in FIG. 3. The charging cable 1 includes a number of power wires 2, in particular six power wires 2, each configured for conducting positive direct current, DC, or negative DC. The power wires 2 are arranged around a coolant supply tube 11, in particular a water supply tube, such that, for example, alternately one power wire 2 conducts positive DC and another, next power wire 2 conducts negative DC. The coolant supply tube 11 is configured for transporting coolant, such as water through the charging cable 1, and has a surface area of about 300 mm.sup.2.

[0039] The charging cable 1 is further provided with an earth wire 12 running parallel to the coolant supply tube 11. The earth wire 12 is provided for providing a protective earth to the charging cable 1. As shown in FIG. 3, the earth wire 12 includes an earth wire mantle 13 that is woven coaxially over the coolant supply tube 11. The earth wire mantle 13 increases the diameter of the coolant supply tube 11 slightly, such that the power wires 2 fit better around the coolant supply tube 11.

[0040] Furthermore, the charging cable 1 includes an outer mantle 14 provided around the power wires 2, the coolant supply tube 11, and the earth wire 12, in order to shield them from the environment. Although not shown in FIG. 3, the outer mantle 14 includes, from inside to outside, a thin plastic sleeve, an earthed EMC shield, a thin plastic sleeve, a hard plastic spiral to prevent buckling, a thin plastic wrap to prevent sticking of an outer layer to the spiral, and the outer layer.

[0041] The outer diameter of the charging cable 1 is about 5 cm and the weight of the charging cable 1 is in the range of 4.2 kg/m. The charging cable 1 according to the disclosure with a total length of about 5.5 m is well manageable for a user with proper support.

[0042] A schematic view of an electric vehicle supply equipment, EVSE, 20 according to an embodiment of the disclosure, is shown in FIG. 4. The EVSE 20 includes the charging cable 1 and a charging connector 21. The EVSE 20, for example, is connected to a not shown alternating current, AC, grid via a transformer and/or a converter for receiving electrical energy from the AC grid. The received electrical energy is transformed and/or converted into DC suitable for charging an electric vehicle by the EVSE 20. The transformed and/or converted DC is intended for being supplied to a not shown electric vehicle via the charging cable 1, which may have a length of about 5.5 m, wherein the electric vehicle is connected to the EVSE 20 by the charging connector 21. The EVSE 20 charges the electric vehicle with a current equal to or up to 3000 A, when the EVSE 20 charges at a single charging cable 1, or to 500 A, when the EVSE 20 charges at two charging cables 1.

[0043] The EVSE 20 further includes a cooling unit 22 with, for example, a liquid coolant reservoir, in particular an ultrapure water/glycol mixture reservoir, a heat exchanger for cooling the liquid coolant, and a pump for circulating the coolant from the liquid coolant reservoir towards the charging connector 21 via the coolant supply tube 11. The charging connector 21 is configured for returning the coolant towards the cooling unit 22 via the coolant space 5 of each of the power wires 2, such that the coolant flows around the power conductor 3 of each power wire 2 for cooling the power wires 2. The pump, for example, is configured to pump 7 liters of coolant through the coolant supply tube 11 per minute.

[0044] It is to be understood that the above description is included to illustrate the operation of the example embodiments and is not meant to limit the scope of the disclosure. From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the scope of the present disclosure.