Heat dissipation arrangement for a charging station, a corresponding charging cable and a control unit

Abstract

The invention relates to a cooling arrangement (1) for a charging station (2) comprising a charging station housing (21) and a charging cable (3), wherein the charging station housing has a fluid outlet (23) and a fluid inlet (24) and wherein the charging cable (3) comprises a cooling circuit which is fluidically connected to the fluid outlet (23) and the fluid inlet (24), characterized in that the charging station housing (21) is at least partially double-walled, the fluid inlet (24) opens into an inlet opening (51) of the double-walled section (5), the double-walled section (5) is thermally coupled to and / or bounded by an outer surface of the charging station housing (21) and an outlet opening (52) of the double-walled section (5) opens into the fluid outlet (23) of the charging station housing (21). Furthermore, a charging cable (3) and a control unit (6) for a heat dissipation arrangement according to the invention are described.

Description

[0001] The invention is based on a charging station for an electrical energy storage device of a motor vehicle, which can be connected to the energy storage device by means of a charging cable. The charging station has a cooling device with at least one cooling line connectable to the motor vehicle for supplying a coolant to the energy storage device. Such a charging station is known from DE 10 2010 007 975 B4. Similar arrangements, in particular with different configurations of the charging cable, are described in DE 10 2016 206 266 A1, DE 20 2015 009 531 U1, DE 10 2015 112 347 A1, DE 10 2017 115 241 A1, and DE 10 2016 224 106 A1. DE 10 2021 006 489 A1 also describes the use of supercooled boiling of the coolant when charging motor vehicles. Further relevant arrangements are known from DE 10 2009 060 398 A1, DE 10 2021 207 803 A1, DE 10 2019 204 957 A1, WO 99 / 08 354 A1, and EP 2 765 672 B1.

[0002] The charging stations known from the prior art have the disadvantage that they require a separate, active cooling device to cool the heated fluid, which increases the energy demand for cooling the charging cable. Known cooling devices for such charging stations often include at least a pump or compressor, a recooling unit, and other complex components to carry out the thermodynamic process required for cooling. Accordingly, the complexity of the charging station increases, the installation space requirement increases, and the cooling device requires additional energy.

[0003] It is therefore the object of the invention to further develop a charging station of the type described above in such a way that it enables simplified, energy-saving cooling of the coolant.

[0004] This object is achieved by a cooling arrangement having the features of claim 1. The subordinate claim 14 relates to a corresponding charging cable. Advantageous embodiments are the subject of the dependent claims.

[0005] Accordingly, it is provided that a cooling arrangement according to the invention for a charging station comprises a charging station housing and a charging cable, wherein the charging station housing has a fluid outlet and a fluid inlet, and wherein the charging cable comprises a cooling circuit that is fluidically connected to the fluid outlet and the fluid inlet. The charging station housing is characterized in that it is double-walled at least in sections, the fluid inlet opens into an inlet opening of the double-walled section, the double-walled section is thermally coupled to and / or delimited by an outer side of the charging station housing, and an outlet opening of the double-walled section opens into the fluid outlet of the charging station housing.A fluid guided in the heat dissipation arrangement is guided in such a way that it enters the cooling circuit of the charging cable via the fluid outlet, can absorb thermal energy when passing through at least a section of the charging cable and re-enters the charging station housing as a heated fluid via the fluid inlet.

[0006] Because the charging station housing is double-walled at least in sections, and this double-walled section is thermally coupled to and / or delimited by the exterior of the charging station housing, the invention enables the fluid to be cooled via the ambient air temperature. This passive cooling eliminates the need for a separate, active cooling unit or at least reduces its size. After passing through the double-walled section, the cooled fluid then returns to the charging cable's cooling circuit via the fluid outlet to absorb further heat energy.

[0007] The double-sided section can be formed by sheet metal forming, by inserting guide elements, and / or by inserting channels, for example, also through 3D printing processes. Preferably, the material of the double-sided section has good thermal conduction properties, at least toward the outside of the charging station housing, and / or has connecting elements to the outside that enable thermal energy to be dissipated. In particular, the connecting elements can be designed as a rib structure.

[0008] A charging station is defined here as a charging station with a power source, which can be installed, in particular, as a standalone unit in publicly accessible locations. Such a charging station is particularly suitable for charging energy storage devices, such as those used in electric or hybrid vehicles.

[0009] A fluid is understood here to be a coolant suitable for absorbing heat released during the charging process, particularly in the charging cable. The fluid can be either gaseous or liquid; in particular, it can be a liquid-vapor mixture when absorbing the released heat. The fluid preferably has dielectric properties.

[0010] The double-walled section is preferably designed in a meandering pattern. This allows the invention to achieve the largest possible contact area between the fluid and the outer wall, or the residence time of the fluid in the double-walled section is increased, allowing more thermal energy to be transferred between the fluid and the ambient air. Meandering here means that the double-walled section has multiple turns. These turns are preferably aligned parallel to an outer side of the charging station housing, so that the thermal coupling with the outer side and / or the boundary by the outer side takes place over the largest possible area of ​​the double-sided section.

[0011] The double-walled section preferably has structures on its inside that enlarge the surface area of ​​the section. This can improve heat transfer because the contact area between the fluid and the environment is increased. The structures preferably influence the flow of the fluid, for example, by promoting recirculation or turbulence, so that a residence time is further increased and / or convective heat transfer between the fluid and the wall of the double-walled section is increased. Possible structures include, for example, depressions in the double-sided section, which can protrude into the section like bulges and / or protrude from the section like dents.

[0012] Preferably, the double-walled section is arranged on the rear exterior side of the charging station housing. This allows the invention to ensure that the front side, which typically houses operating elements, is not affected by the fluid cooling during use. In particular, this prevents excessive heating due to the cooling of the fluid at the front, which could potentially lead to injuries to users.

[0013] Preferably, the inlet opening of the double-walled section is arranged a vertical distance above the outlet opening. This allows the fluid to flow through the double-walled section from top to bottom, creating a self-flow due to gravity and a decrease in density as a result of cooling, thus reducing the need for pumping.

[0014] The charging station housing preferably has an air inlet that is open to the surroundings of the charging station and opens into an air duct that is thermally coupled to and / or delimits an inner side of the double-walled section. The invention thus enables the double-walled section to have, at least in some regions, two contact sides for heat transfer, i.e., to have the largest possible contact area with the surroundings. This advantageously cools the fluid. The inner side is understood to be the wall of the double-walled section that faces the interior of the charging station, i.e., faces away from the surroundings of the charging station.

[0015] Preferably, the air inlet is located on the underside of the charging station housing and flows past the double-walled section from bottom to top. Since the fluid flows through the double-walled section from top to bottom, the air in the upper area is warmer, resulting in a natural airflow due to the density differences.

[0016] The air duct preferably has a ventilation unit. The invention thus enables a continuous air flow through the air duct, which can improve heat dissipation. Furthermore, the ventilation unit allows for the air flow direction to be specified, so that the air flows horizontally through the charging station housing, for example. Depending on the design requirements, greater flexibility can be achieved. The ventilation unit can be arranged in the air duct, but also upstream or downstream of the air duct.

[0017] The air duct preferably has a cooling module. This allows for further increased cooling performance. Especially at high ambient temperatures, a defined cooling performance can be achieved. A heat exchanger can be used as the cooling module, in particular.

[0018] Preferably, at least one fluid guide element extends between and adjacent to an inner and outer side of the double-walled section, over which the fluid guided through the double-walled section is guided in a meandering pattern. The invention thus enables a relatively simple design for guiding the fluid in a meandering pattern through the double-walled section.

[0019] Preferably, a plurality of parallel and horizontal fluid guide elements extend between the inner side and the outer side, delimiting the double-walled section between them and extending alternately from opposite end faces of the outer side, each reaching to the opposite end face while maintaining a distance. The invention thus enables the fluid to be guided through the double-walled section across multiple horizontal planes. The fluid flows horizontally over each fluid guide element and is then deflected vertically onto the following horizontal plane. The fluid guide elements can also be made of a thermally conductive material and designed to preferentially dissipate the absorbed heat to the outside, for example by having an insulating core layer.

[0020] For delivering electrical energy to a receiver, the charging cable is preferably connected to the charging station at a first end and to the receiver at a second end. Preferably, the first end to the charging station and / or the second end to the receiver are designed as detachable connections. For example, the charging cable can have a first plug connection at the second end for connecting to a second plug connection of the receiver.

[0021] Receivers of electrical energy are understood here to be, for example, motor vehicles such as electric vehicles or hybrid vehicles. In principle, however, within the meaning of the invention, a receiver can be any device that includes an energy storage device that must be recharged with electrical energy after a period of use.

[0022] Preferably, the heat dissipation arrangement comprises a pump unit, wherein the pump unit guides the fluid from the charging station housing via the fluid outlet into the cooling circuit of the charging cable to the receiver and via the fluid inlet as heated fluid from the cooling circuit of the charging cable back into the charging station housing.

[0023] As a pumping unit, the charging station here comprises a pump, a compressor or another device suitable for circulating the fluid so that the fluid can flow through the cooling circuit of the charging cable to the receiver and back to the charging station as well as through the double-walled section.

[0024] A charging cable according to the invention for a heat dissipation arrangement has a cavity between a conductor and an insulation layer. The cooling circuit of the charging cable is either routed at least partially within the cavity, or the cavity is designed as at least one section of the cooling circuit. The invention thus enables the conductor to be cooled by the fluid that is routed at least partially within the cavity.

[0025] A conductor is defined here as an electrically conductive material suitable for transmitting electrical energy from the charging station to the receiver. The charging cable can also comprise more than one conductor. This is particularly advantageous for achieving high charging power. The conductors are surrounded by an insulating layer.

[0026] Especially at high charging power levels, heat is released in the conductor, necessitating cooling to ensure the charging cable can be used safely and does not sustain damage. Therefore, a cavity is provided between the conductor and the insulation layer, in which the cooling channel is routed at least partially or forms at least a section of the cooling circuit. This arrangement enables direct cooling of the conductor by the fluid, thus preventing or at least reducing overheating of the charging cable, even at high charging power levels.

[0027] Sectionally or as a section is understood to mean that a part of the cooling channel is guided in the cavity or that the cavity directly forms part of the cooling channel. This can be designed, for example, such that a part of the cooling channel, in which the fluid is guided from the charging station housing to the receiver, is guided partially or completely in the cavity. Alternatively or additionally, a part of the cooling channel, in which fluid is returned from the receiver to the charging station housing, can be guided partially or completely in the cavity. Instead of guiding a section of the cooling channel in the cavity, the cavity itself can be designed as part of the cooling channel within the meaning of the invention. In this case, a charging cable according to the invention is not limited to having exactly one cavity between the conductor and the insulation layer.Rather, the charging cable according to the invention can also have several, preferably separate, cavities between the conductor and the insulation layer.

[0028] A control unit for a cooling arrangement is designed and configured to control the cooling arrangement, wherein the control comprises adjusting a pumping power of the pumping unit, adjusting a fan speed of the ventilation unit, and / or actuating a valve means. The invention thus enables the operation of the cooling arrangement to be adjusted by setting a changed flow rate of the fluid, a changed cooling of the fluid, and / or a routing of the fluid to the electrical energy storage device. Preferably, the control unit can access stored information, for example, using look-up tables, and perform the adjustment based on a charging power and / or a charging duration.Alternatively or additionally, the control unit may also contain information from the receiver or receive a signal by closing a contact, so that the control unit can detect whether the valve means is to be actuated in order to supply the electrical energy storage device with fluid.

[0029] A further control unit for the cooling arrangement is designed and configured to monitor the cooling arrangement, wherein the monitoring comprises the following steps: - Recording measurement data from a sensor unit, - Comparing the recorded measurement data with one or more threshold values ​​and - Based on comparing, issuing a warning and / or interrupting a charging operation.

[0030] Sensor units can be provided in the cooling arrangement, which can exchange information with the control unit, so that the control unit can, for example, detect a temperature, a pressure, and / or a volume flow of the fluid at one or more points of the cooling arrangement. Based on this information, the control unit can detect whether a defect exists, such as a leak due to a pressure drop or overheating. It can also be provided that another sensor unit detects a surface temperature of the charging cable, so that the control unit can detect when the surface temperature is too high for use.

[0031] The control unit detects whether a defect is present by comparing the recorded measurement data with one or more threshold values ​​that indicate a departure from a target range. The threshold values ​​can be stored in a memory unit of the control unit. If the comparison reveals that one or more threshold values ​​are exceeded, the control unit issues a warning, for example, by displaying a message on the charging station and / or transmitting it to an operating company, and / or interrupts charging. The latter is particularly useful if there is otherwise a risk of injury or if permanent damage to the charging station, the receiver, and / or the cooling system is likely to occur.

[0032] Preferably, the control unit is designed and configured to regulate the cooling arrangement, wherein the regulation comprises controlling the cooling arrangement based on the comparison of the monitoring. The invention thus enables the control of the pump unit, the ventilation unit, and / or the valve means based on a system state of the cooling arrangement, thus enabling adapted operation. In particular, a temperature of the fluid can be adjusted such that advantageous heat transfer in the charging cable can be achieved, so that a surface temperature of the charging cable can be maintained within a target range even at high charging power levels.

[0033] Further details of the invention are explained with reference to the following figures. Fig. 1 a charging system for a motor vehicle; Fig. 2 shows a cooling arrangement for a charging station according to an embodiment of the invention; Fig. 3 is a schematic representation of a charging system for a motor vehicle with a cooling arrangement according to an embodiment of the invention; and Fig. 4 a cross-sectional view of a charging cable according to an embodiment of the invention.

[0034] Fig. 1 shows a charging system 10 for charging a receiver 4, here embodied as an electric vehicle, comprising a charging station 2 having a charging station housing 21 and a charging cable 3. The charging station 2 includes a power source (not shown). The charging cable 3 is connected to the charging station 2 at a first end 31 for delivering electrical energy from the power source to the electric vehicle 4, and has a first plug connection 33 at a second end 32 for connecting to a second plug connection 43 of the electric vehicle 4, so that electrical energy can be transferred from the charging station to the electric vehicle 4. The electric vehicle 4 has a charging electrical system 41, which includes a converter, and an electrical energy storage device 42. The charging electrical system 41 is connected to the charging cable 3, so that the electrical energy storage device 42 can be charged via the charging electrical system 41.

[0035] Particularly at high charging powers, for example, more than 100 kW, which are necessary to achieve shorter charging times, preferably in the single-digit minute range, the challenge arises that large amounts of thermal energy are released, which can cause very high temperatures in the charging cable 3 on the one hand, and in the electrical energy storage device 42 on the other. These high temperatures can lead to damage to the charging cable 3 and / or the electrical energy storage device 42, but in particular also pose a risk of injury if the outside of the charging cable 3 also reaches temperatures that can cause burns to a user.

[0036] In known embodiments from the prior art, charging cables 2 are therefore proposed, for example, which cool the charging cable 3 by conducting a gaseous or liquid coolant. It is also known to conduct coolant to the electrical energy storage device 42, so that this can also be protected from harmful heating. However, a disadvantage is that the charging stations 2 from the prior art have an active cooling device integrated into the charging station 2 for recooling the coolant. This cooling device requires additional installation space within the charging station 2 and has an additional energy requirement.

[0037] To solve this problem, the invention proposes a Fig. 2 shows the cooling arrangement 1 for the charging station 2, which differs from the charging stations 2 known from the prior art in that the charging station housing 21 is used as a heat sink. For this purpose, the charging station housing 21 is designed with a double wall, at least in sections. This is shown in Fig. 2, in which a rear outer side 211 of the charging station housing 3 is only partially shown, so that the double-walled section 5 can be seen. The double-walled section 5 is arranged on the rear outer side 211 and extends here over a large part of the height of the charging station housing 21. The double-walled section 5 is designed to carry a fluid that can be used to cool the charging cable 3 and / or the electrical energy storage device 42 and for this purpose has an inlet opening 51 and an outlet opening 52. The double-walled section 5 is delimited by the rear outer side 211 and at the same time thermally coupled to it, so that a heat exchange can take place between the fluid and the ambient air.

[0038] The inlet opening 51 of the double-walled section 5 is arranged a vertical distance above the outlet opening 52. This allows the pumping power required to convey the fluid to be reduced, since the fluid acquires a natural flow direction due to gravity and the increase in density resulting from cooling from top to bottom.

[0039] In order to increase the distance of the fluid over which heat transfer can take place via the rear outer side 211, the fluid is redirected several times through the double-walled section 5 so that it is guided in a meandering manner. For this purpose, a plurality of parallel and horizontal fluid guide elements 55 extend between an inner side 53 and a Fig. 3 visible outer side 54, which here corresponds to the rear outer side 211 of the charging station housing, of the double-walled section 5. The fluid guide elements 55 delimit the double-walled section 5 between them and are arranged such that they extend alternately from opposite end faces 56 and each reach the opposite end face 56 while maintaining a distance. The fluid guided through the double-walled section 5 flows over the respective fluid guide elements 55 in a horizontal direction and is deflected vertically in the opposite, horizontal direction at the end of each fluid guide element 55. In this way, the path that the fluid travels in the double-walled section 5 is increased, whereby both a heat transfer surface and a residence time can be increased, and thus heat transfer with the environment can be increased.

[0040] In other embodiments, the double-walled section 5 can have structures on its inside that enlarge the surface of the section 5. For example, in the embodiment shown, the inside of the outer side 54 could have a corrugated surface, comparable to the surface of a golf ball, thus increasing the heat transfer area on the one hand and influencing the flow by increasing turbulence on the other, so that heat transfer is improved. Structures such as ribs projecting into the section 5 or forming the double-walled section from, for example, small 3D-printed channels with variable cross-sections are also feasible.

[0041] Fig. 3 schematically shows the charging system 10 for the electric vehicle 4 with the cooling arrangement 1. The charging station housing 21 has a pump unit 22, a fluid outlet 23, and a fluid inlet 24. The charging cable 3 has a fluid circuit with a first section 34 and a second section 35 for conducting the fluid between the charging station 2 and the electric vehicle 4. The pump unit 22 guides the fluid from the charging station housing 21 via the fluid outlet 23 through the first section 34 to the electric vehicle 4 and through the second section 35 back into the charging station housing 21 as heated fluid via the fluid inlet 24. The fluid inlet 24, through which the fluid re-enters the charging station housing 21, opens into the inlet opening 51 of the double-walled section 5.The outlet opening 52 of the double-walled section 5 ultimately opens into the fluid outlet 23 of the charging station housing 21, allowing the cooled fluid to flow back toward the electric vehicle 4. A reservoir 28 and the pump unit 22 are connected between the outlet opening 52 and the fluid outlet 23. The pump unit 22 is designed as a compressor here.

[0042] In the embodiment shown here, the charging station housing 21 has an air inlet 25 that is open to the surroundings of the charging station 2 and opens into an air duct 26 that is thermally coupled to and delimits the inner side 53 of the double-walled section 5. Furthermore, in order to be able to generate a continuous air flow in the air duct 26, the air duct 26 has a ventilation unit 27. The ventilation unit 27 is arranged here such that it draws in the ambient air from the underside of the charging station housing 21 and the air thus flows from bottom to top past the double-walled section 5. The invention thus enables the fluid in the double-walled section 5 to release heat to the ambient air on both sides.

[0043] In other exemplary embodiments, the air flow may be directed horizontally past the double-walled section 5, for example, by arranging the air inlet 25 on one of the end faces 56 of the charging station housing 21. Alternatively or in addition to the ventilation unit 27, the air duct 26 may also be provided with a cooling module, such as a heat exchanger, to further increase cooling performance.

[0044] In order to also enable cooling of the electrical energy storage device 42, the first plug connection 33 has valve means 331 which are designed to redirect the fluid from the first section 34 into the second section 35 and / or to direct at least a portion of the fluid into the second plug connection 43, wherein the second plug connection 43 is designed to feed at least a portion of the fluid back to the second section 35. For an electric vehicle 4 which has a cooling system for the electrical energy storage device 42 which can be coupled to the second plug connection 43, the fluid can thus be passed on via the second plug connection 43 to the electrical energy storage device 42 in order to be fed from there back to the second section 35 via the second plug connection 43.

[0045] It can be provided that a user of the charging system 10 manually actuates the valve means 331. However, it is advantageous if the charging system can independently recognize a compatible electric vehicle 4. For this purpose, it comprises a control unit 6 that can communicate with the charging electrical system 41 of the electric vehicle 4. If the control unit 6 receives information from the charging electrical system 41 that the electric vehicle 4 is compatible with the heat dissipation arrangement 1 and that cooling is required, the control unit 6 actuates the valve means 331 so that the electrical energy storage device 42 is accordingly supplied with fluid for cooling. Alternatively, instead of communication between the control unit 6 and the charging electrical system 41, a contact can be provided in each of the first 33 and the second 43 plug connections.If the contact is closed because the electric vehicle 4 is compatible with the heat dissipation arrangement 1, the control unit 6 causes the valve means 331 to be actuated; otherwise, it keeps them closed so that the fluid is diverted directly in the first plug connection 33 into the second section 35.

[0046] To execute the actuation of the valve means 331, the control unit 6 contains a corresponding control program. The control program contains further commands to actuate the compressor of the pump unit 22 and the ventilation unit 27. Thus, by controlling the pump unit 22, the control unit allows the adjustment of a fluid flow rate and a cooling intensity. By controlling the ventilation unit, the control program can, for example, change a fan speed to influence the cooling of the fluid in the double-walled section 5.

[0047] The control program performs the actuation of the ventilation unit 27 and the pump unit 22 based on stored look-up tables, so that it selects and accordingly actuates the pump power and fan speed based on a charging power and / or a charging duration.

[0048] The control unit 6 further includes a monitoring program to detect, for example, a malfunction. For this purpose, the charging system 10 is equipped with several sensor units 61, 62, 63. The first sensor 61 and the second sensor 62 are arranged upstream of the fluid outlet 23 and downstream of the fluid inlet 24, respectively, and are designed to measure the temperature, pressure, and volume flow of the fluid. This provides information about the condition of the fluid both before it flows into the charging cable 3 and after it flows through the charging cable 3. The third sensor 63 is positioned outside the charging station housing 21 on the surface of the charging cable 3 and provides data on the surface temperature of the charging cable 3.

[0049] Based on this information, the monitoring program can issue a warning and / or interrupt the operation of the charging system 10 based on stored information such as a threshold value for the surface temperature of the charging cable 3. Furthermore, the monitoring program can conclude that there is a leak based on a pressure difference between the first 61 and the second 62 sensor unit exceeding a further threshold value and / or that there is a defect in the double-walled section 5 if the temperature difference is correspondingly high. In these cases, too, the control program includes commands to issue a warning and / or interrupt operation if corresponding threshold values ​​are exceeded.

[0050] In an alternative embodiment, the control unit 6 comprises a control program in addition to or as an alternative to the control program. Like the monitoring program, the control program uses the measurement data from the sensor units 61, 62, and 63. However, it also includes commands to actuate the pump unit 22 and / or the ventilation unit 27 depending on the measurement data. If, for example, the surface temperature of the charging cable 3 is higher than a stored threshold value, the control program can increase a fan speed and / or the pump power in order to increase a volume flow of the fluid and / or to enhance cooling of the fluid. If a temperature difference between the first 61 and the second 62 sensor unit exceeds a further threshold value, the control unit can also actuate the ventilation unit 27 in order to adjust cooling of the fluid.In particular, it is also possible to switch off the ventilation unit 27 when the temperature difference is within a target range.

[0051] Fig. 4 shows the charging cable 3 for a Fig. 2 and Fig. 3 in four different embodiments. In all variants, the charging cable 3 has a hollow space 38 between a conductor 36 and an insulating layer 37. The conductor 36 is electrically conductive and can be electrically contacted at both ends in order to transmit the electrical energy between the charging station 2 and the electric vehicle 4. The insulating layer 37 surrounds the conductor 36 circumferentially in order to electrically shield the surroundings. Since a relatively large amount of thermal energy is released in the conductor 36 due to ohmic losses when high charging power is transmitted, the conductor 36 can heat up so much during operation that the charging cable 3 is damaged or even poses a risk of injury.

[0052] Therefore, the cavity 38 is provided here, in which the first 34 and / or the second 35 section of the cooling circuit of the charging cable 3 is guided. The invention thus enables almost direct cooling of the conductor 36 by the fluid.

[0053] In the first exemplary embodiment (top left), the first 34 and second 35 sections each comprise four channels through which the fluid is guided. The flow direction for the first section 34 is opposite to the flow direction of the second section 35. This is indicated here by the flow direction of the first section 34 being marked with an X and directed into the plane of the drawing. For the second section 35, the flow direction is marked with a dot and directed out of the plane of the drawing.

[0054] The fluid is guided through the four channels of the first section 34 from the charging station 2 to the first plug connection 33, absorbing heat from the conductor 36. From the first plug connection 33, the fluid flows directly back via the second section 35 and / or, depending on the valve means 331, is first guided to the electrical energy storage device 42 before reaching the second section 35. On the way back to the charging station 2 through the second section 35, the fluid flows past the conductor 36 again and can thus absorb heat again. Because the channels of the first 34 and second 35 sections are arranged circumferentially around the conductor 36, they can also absorb thermal energy released in different directions. In other exemplary embodiments, it can be provided that the first 34 and / or the second 35 sections comprise more or fewer channels in order to further increase heat transfer or reduce complexity.

[0055] In the second exemplary embodiment (top right), the charging cable 3 has the same basic principle as in the first exemplary embodiment. However, in order to provide a higher charging power, the charging cable here comprises three conductors 36, each of which is circumferentially surrounded by a hollow space 38 and an insulating layer 37. Each conductor 36 is cooled by four channels in the first section 34 and the second section 35, so that the released heat can be dissipated by the fluid. The three conductors 36, including the hollow spaces 38 and insulating layers 37, are in turn surrounded by an outer cable sheath 39.

[0056] In the third exemplary embodiment at the bottom left, the charging cable 3, as in the second exemplary embodiment, comprises three conductors 36, each of which is circumferentially surrounded by a hollow space 38 and an insulating layer 37. Here, however, the first section 34 and the second section 35 do not have four individual channels per conductor 36. Instead, the first section 34 is formed by the hollow spaces 38 formed between the insulating layers 37 and the conductors 36; the fluid of the first section 34 therefore completely surrounds the conductors 36, so that heat transfer can be further improved. The second section 35, on the other hand, is formed by an intermediate space 64 that surrounds the conductors 36 outside the insulating layers 37 and is delimited by the outer cable sheath 39.

[0057] In this exemplary embodiment, the fluid flows from the charging station 2 through the three first sections 34, directly past the conductors 36, and absorbs the released thermal energy. On its return path through the second section 35, the fluid flows around the conductors 36 outside the insulation layers 37 in the intermediate space 64, thus further reducing the charging cable temperature. In other exemplary embodiments, the first section 34 is provided in the intermediate space 64, and the second section 35 is arranged in the cavities 38 between the conductors 36 and the insulation layers 37.

[0058] Here, the first sections 34 are designed so that the fluid is in direct contact with the conductor 36, meaning there is no wall between the cavity 38 and the conductor 36. The fluid therefore has dielectric properties, such as HFE-7100.

[0059] In the last exemplary embodiment, bottom right, a variant of the charging cable 3 is shown that is similar to the third exemplary embodiment. Here, however, not each conductor 36 is surrounded by an individual cavity 38 and an individual insulation layer 37, but rather the three conductors 36 are surrounded by a common cavity 38 and a common insulation layer 37. The common cavity 38 is designed as the first section 34, which here too has no wall opposite the conductors 36, so that they are directly cooled by the dielectric fluid. The second section 35 is arranged in the intermediate space 64 so that the fluid can cool the charging cable 3 outside the insulation layer 37 on its way back to the charging station 2. In order to increase heat transfer between the insulation layer 37 and the second section 35, the insulation layer 37 has six ribs 65 on its outer side, so that a heat transfer surface is enlarged.

[0060] In all exemplary embodiments, cooling of the conductor 36 is achieved at least temporarily by evaporating the fluid, so that a liquid-vapor mixture is preferably present at least in some areas. This has the advantage of improved heat dissipation, since in addition to heat absorption by increasing the fluid's temperature, the latent evaporation enthalpy can also be utilized. For this purpose, the fluid is preferably selected such that the boiling point is just below a maximum target temperature of the charging cable 3. "Just below" here means 15 degrees Celsius, preferably 10 degrees Celsius, particularly preferably 5 degrees Celsius below the target temperature.

[0061] The nucleate boiling range is particularly preferably used, since the heat flux density, i.e., the heat transferred per unit area, is highest here. This can be achieved, for example, by the control program monitoring the inlet and outlet temperatures via sensor units 61 and 62 and adjusting them if necessary so that advantageous heat transfer rates between the conductors 36 and the fluid can be achieved. Preferably, the control program sets the temperature of the fluid at the first sensor 61, i.e., upstream of the fluid outlet 23, so that it is 30 degrees Celsius, preferably 20 degrees Celsius, particularly preferably 15 degrees Celsius below the boiling temperature. List of reference symbols 1 cooling arrangement 2 charging stations 3 charging cables 4 receivers, electric vehicle 5 Double-walled section of the charging station housing 6 Control unit 10 Charging system 21 charging station housings 22 Pump unit 23 Fluid outlet 24 Fluid inlet 25 Air intake 26 Air duct 27 Ventilation unit 28 Reservoir 31 First end of the charging cable 32 Second end of the charging cable 33 First connector 34 First section of the charging cable fluid circuit 35 Second section of the charging cable fluid circuit 36 ladders 37 Insulation layer 38 cavity 39 Cable sheathing 41 Charging electrics 42 Electrical energy storage 43 Second connector 51 Inlet opening of the double-walled section 52 Outlet opening of the double-walled section 53 Inside of the double-walled section 54 Outside of the double-walled section 55 Fluid guide element 56 front side 61, 62, 63 sensor units 64 space 65 ribs 211 Rear exterior of the charging station housing 331 Valve means

Claims

[1] Cooling arrangement (1) for a charging station (2) comprising a charging station housing (21) and a charging cable (3), wherein the charging station housing (21) has a fluid outlet (23) and a fluid inlet (24) and wherein the charging cable (3) comprises a cooling circuit which is fluidically connected to the fluid outlet (23) and the fluid inlet (24), characterized by that the charging station housing (21) is at least partially double-walled, the fluid inlet (24) opens into an inlet opening (51) of the double-walled section (5), the double-walled section (5) is thermally coupled to and / or delimited by an outer side of the charging station housing (21), and an outlet opening (52) of the double-walled section (5) opens into the fluid outlet (23) of the charging station housing (21). [2] Heat dissipation arrangement (1) according to claim 1, wherein the double-walled section (5) is designed in a meandering shape. [3] Heat dissipation arrangement (1) according to claim 1 or 2, wherein the double-walled section (5) has structures on the inside which enlarge a surface of the section (5). [4] Heat dissipation arrangement (1) according to one of the preceding claims, in which the double-walled section (5) is arranged on a rear outer side (211) of the charging station housing (21). [5] Heat dissipation arrangement (1) according to one of the preceding claims, in which the inlet opening (51) of the double-walled section (5) is arranged a vertical distance above the outlet opening (52). [6] Cooling arrangement (1) according to one of the preceding claims, in which the charging station housing (21) has an air inlet (25) which is open to the surroundings of the charging station (2) and opens into an air duct (26) which is thermally coupled to and / or delimits an inner side (53) of the double-walled section (5). [7] Cooling arrangement (1) according to claim 6, wherein the air duct (26) has a ventilation unit (27). [8] Cooling arrangement (1) according to claim 6 or 7, wherein the air duct (26) has a cooling module. [9] Heat dissipation arrangement (1) according to one of the preceding claims, in which at least one fluid guide element (55) extends between an inner side (53) and an outer side (54) of the double-walled section (5) and adjacent thereto, over which the fluid guided through the double-walled section (5) is guided in a meandering manner. [10] Heat dissipation arrangement (1) according to claim 9, in which a plurality of parallel and horizontal fluid guide elements (55) extend between the inner side (53) and the outer side (54), which define the double-walled section (5) between them and which extend alternately from opposite end faces (56) of the outer side (54) and each reach the respective opposite end face (56) while maintaining a distance. [11] Cooling arrangement according to one of the preceding claims, wherein the charging cable (3) for delivering electrical energy to a receiver (4) is connected with a first end (31) to the charging station (2) and with a second end (32) to the receiver (4). [12] Heat dissipation arrangement according to claim 11, wherein the charging cable (3) has a first plug connection (33) at the second end (32) for connecting to a second plug connection (43) of the receiver (4). [13] Cooling arrangement according to one of the preceding claims, comprising a pump unit (22), wherein the pump unit (22) guides the fluid from the charging station housing (21) via the fluid outlet (23) into the cooling circuit of the charging cable (3) to the receiver (4) and via the fluid inlet (24) as heated fluid from the cooling circuit of the charging cable (3) back into the charging station housing (21). [14] Charging cable (3) for a heat dissipation arrangement (1) according to one of claims 1 to 13, characterized by that the charging cable (3) has a cavity (38) between a conductor (36) and an insulation layer (37) and the cooling circuit of the charging cable (3) is guided at least partially in the cavity (38) or the cavity (38) is designed at least as a section of the cooling circuit. [15] Charging cable (3) according to claim 14, characterized bythat the fluid has dielectric properties and the conductor (36) is in direct contact with the fluid. [16] Charging cable (3) according to claim 14 or 15, wherein at least temporary cooling of the conductor (36) is achieved by evaporation of the fluid, so that preferably at least in some areas a liquid-vapor mixture is present. [17] Charging cable (3) according to one of claims 14 to 16 in conjunction with claim 12, wherein the first plug connection (33) has valve means (331) which are designed to redirect the fluid from a first section (34) of the cooling circuit into a second section (35) of the cooling circuit and / or to direct at least a portion of the fluid into the second plug connection (43), wherein the second plug connection (43) is designed to feed the at least a portion of the fluid back to the second section (35).

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