Cooling device, motor vehicle and method for operating a cooling device

Abstract

The invention relates to a cooling device (10) for a motor vehicle, comprising a refrigerant circuit. The compressor is designed to feed the refrigerant compressed in the cooling operation of the refrigerant circuit to the refrigerant cooler. An expansion device is provided for expanding refrigerant from the refrigerant cooler. A water chiller arranged downstream of the expansion device is integrated into the refrigerant circuit of the cooling device on the one hand and into the coolant circuit of the cooling device on the other hand. In the cooling operation, heat can be transferred from a coolant flow flowing through the cooling-water machine to an expanded refrigerant flowing through the cooling-water machine in the cooling operation. The cooling device comprises a control device which is designed to adjust the flow rate of the coolant flowing through the cooling-water machine during the cooling operation. By adjusting the coolant flow, the refrigerant pressure present on the suction side of the compressor can be adjusted. The invention also relates to a motor vehicle and to a method for operating a cooling device.

Description

TECHNICAL FIELD

[0001] The invention relates to a cooling device for a motor vehicle, the cooling device comprising a refrigerant circuit. A compressor of the refrigerant circuit is designed to deliver refrigerant compressed in a cooling operation of the refrigerant circuit to a refrigerant cooler of the refrigerant circuit. An expansion device is provided to expand the refrigerant coming from the refrigerant cooler. A chiller / refrigerator arranged downstream of the expansion device is integrated into the refrigerant circuit of the cooling device on the one hand and into a coolant circuit of the cooling device on the other hand. In the cooling operation, heat can be transferred from a coolant flow flowing through the chiller to the expanded refrigerant flowing through the chiller in the cooling operation. The invention also relates to a motor vehicle having such a cooling device and to a method for operating the cooling device. BACKGROUND

[0002] In particular in an electrified motor vehicle, for example in the form of an electric vehicle or a hybrid vehicle, a chiller integrated into the refrigerant circuit can be used to cool electrical components of the motor vehicle, for example in particular a motor vehicle energy store designed as a high-voltage battery. It can occur in this connection that the coolant entering the chiller has a relatively high temperature. If the chiller provides a correspondingly high cooling power and a large amount of heat is introduced into the refrigerant at the chiller, it can result that a relatively high refrigerant pressure prevails at the suction side of the compressor.

[0003] In particular, if the refrigerant is compressed relatively strongly by the compressor in addition in order to dissipate the heat of the compressed refrigerant in the refrigerant cooler, it can result that the compressor is operated in an operating range associated with an undesired high load of the compressor. In particular, it can result from this that the compressor heats up, which leads to a reduction in power of the compressor or to a shutdown of the compressor. But if the compressor is operated with reduced delivery power or even shut down, the heat of the coolant flowing through the chiller in the cooling operation of the refrigerant circuit can no longer be dissipated in the desired manner by means of the chiller. This is disadvantageous.

[0004] DE 10 2019 107 191 A1 describes a thermal system for an electric or hybrid vehicle, the thermal system having a refrigeration circuit and a cooling circuit. Here, the refrigerant flow through a chiller of the refrigeration circuit is controlled depending on the suction pressure and the temperature of the refrigerant upstream of a compressor of the refrigeration circuit. In addition, the compressor can be controlled depending on the cooling demand on the vehicle interior or on a vehicle high-voltage energy store. The temperature at the air side of an air conditioning evaporator or the temperature of the coolant is used as a control variable here.

[0005] In a thermal system of this type, an undesired strong load of the compressor can also occur in the case of a high cooling demand. SUMMARY

[0006] The object of the application is to provide a cooling device of the type mentioned at the outset, which enables particularly smooth compressor operation even in the case of high cooling power requirements for the chiller, and to provide a motor vehicle having a cooling device and a corresponding method for operating a cooling device.

[0007] The object is achieved by a cooling device having the features of claim 1, a motor vehicle having the features of claim 9 and a method having the features of claim 10. Advantageous design refinements of the application are given in the dependent claims and the following description.

[0008] The cooling device for a motor vehicle according to the application comprises a refrigerant circuit, wherein a compressor of the refrigerant circuit is designed to deliver refrigerant compressed in a cooling operation of the refrigerant circuit to a refrigerant cooler of the refrigerant circuit. An expansion device of the refrigerant circuit is provided to expand the refrigerant coming from the refrigerant cooler. A chiller arranged downstream of the expansion device is integrated into the refrigerant circuit of the cooling device on the one hand and into a coolant circuit of the cooling device on the other hand. In the cooling operation, heat can be transferred from a coolant flow flowing through the chiller to the expanded refrigerant flowing through the chiller in the cooling operation. The cooling device comprises a control device designed to adjust a coolant flow rate of the coolant flowing through the chiller in the cooling operation. Here, by adjusting the coolant flow rate, the refrigerant pressure present at the suction side of the compressor can be adjusted.

[0009] The application is based on the recognition that, in the cooling operation of the refrigerant circuit, the coolant flow flowing through the chiller can be used as a heat source for the expanded refrigerant flowing through the chiller. Since heat can be output from the coolant in the liquid state to the refrigerant, the coolant in the liquid state has a higher temperature in the chiller than the expanded refrigerant. The absorption of heat by the refrigerant leads to an increase in temperature in the refrigerant and thus also to an increase in pressure in the refrigerant.

[0010] Thus, given the temperature difference between the coolant flow flowing through the chiller and the refrigerant flowing through the chiller, the temperature of the refrigerant leaving the chiller and coming from the chiller to the suction side of the compressor and thus also the pressure of the refrigerant can be influenced by changing the coolant flow rate.

[0011] For example, by reducing the coolant flow rate flowing through the chiller, it can be ensured that the pressure in the refrigerant present at the suction side of the compressor decreases. This in turn makes it possible, given the compressor power of the compressor, for the refrigerant at the pressure side of the compressor to have a lower pressure than in the case where the refrigerant with a higher pressure has already been sucked in at the suction side.

[0012] Thus, a reduction in the delivery power of the compressor or even a shutdown of the compressor due to the high pressure on the pressure side and the suction side of the compressor can be prevented as far as possible.

[0013] This is because a reduction in the coolant flow through the chiller in the cooling mode results in less heat being introduced into the expanded refrigerant flowing through the chiller in the cooling mode. The associated lower temperature increase of the refrigerant in turn leads to a lower refrigerant pressure at the outlet on the refrigerant side of the chiller. As a result, the pressure of the refrigerant on the suction side of the compressor is also reduced.

[0014] By adjusting the refrigerant flow through the chiller, the pressure on the suction side of the compressor can be reduced accordingly in order to keep the compressor in an operating range in which a reduction in the power of the compressor and / or a shutdown of the compressor does not occur or occurs only rarely. Thus, even in the case of a high demand for the cooling power of the chiller, the cooling device can achieve particularly smooth operation of the compressor.

[0015] Preferably, the control device is designed to adjust the coolant flow taking into account a measured value of a temperature sensor, wherein the temperature sensor is designed to detect the coolant flow temperature at the coolant inlet of the chiller. This is based on the recognition that, given a coolant flow, more heat is introduced into the refrigerant in the case of a higher coolant temperature at the coolant inlet in the chiller than in the case of a lower coolant temperature at the coolant inlet. The measured value of the temperature sensor is therefore particularly suitable for adjusting the coolant flow through the chiller in the cooling mode of the refrigerant circuit in accordance with the demand.

[0016] It has proven to be more advantageous if the control device is designed to adjust the coolant flow taking into account a theoretical value of the cooling power that should be provided by the chiller in the cooling mode. Since this theoretical value makes it clear how much heat should be dissipated from the coolant in the chiller during the cooling mode, this facilitates the adjustment of the coolant flow in accordance with the demand by the control device.

[0017] In order to determine whether the chiller provides the required cooling power in the cooling mode, in particular the volume flow of the coolant through the chiller, and the coolant temperature at the coolant inlet and the coolant temperature at the coolant outlet of the chiller can be detected. For this purpose, a further temperature sensor is preferably arranged at the coolant outlet of the chiller.

[0018] Preferably, the control device is designed to operate a pump device in order to adjust the coolant flow, by means of which the coolant can be conveyed through the chiller. Thereby, in particular the volume flow of the coolant conveyed through the chiller in the cooling mode can be adjusted in accordance with the demand.

[0019] With the temperature difference between the expanded refrigerant and the coolant flowing through the chiller in the cooling mode given, a reduction in the volume flow of the coolant ensures an increase in the temperature difference of the coolant between the coolant inlet of the chiller and the coolant outlet of the chiller. The reduction in the volume flow of the coolant can be achieved by the actuation of the pump device. This is because a smaller volume flow is cooled more strongly by the refrigerant than a larger volume flow. Thus, despite the reduction in the volume flow of the coolant flowing through the chiller in the cooling mode, the motor vehicle components that can be loaded with coolant can still be cooled sufficiently. This is advantageous.

[0020] It has also proven to be advantageous for the chiller to be arranged in a sub-branch of the coolant circuit. Here, the control device is designed to actuate the valve device to regulate the coolant flow, wherein the sub-branch can be at least partially opened / released by the actuation of the valve device. In this way, it can be ensured that the coolant partial flow that flows through the sub-branch of the coolant circuit is cooled in the cooling mode of the refrigerant circuit in such a way that heat is transferred from the coolant partial flow to the expanded refrigerant. As a result, it can be achieved that it is not necessary to feed the entire coolant flow that flows through the coolant circuit through the chiller. This is advantageous for a very flexible coolant circuit operation, wherein the operation of the coolant circuit can be adapted to the respective cooling requirements of the components arranged in the coolant circuit.

[0021] Preferably, the coolant circuit comprises a further line branch, from which the sub-branch branches off at the valve device. Here, the coolant partial flow from the chiller and a further coolant partial flow that flows through the further line branch can be merged at a node of the coolant circuit. In this way, it can be achieved that the cooled coolant from the chiller is mixed with the further partial flow that flows through the further line branch.

[0022] This is particularly advantageous in the case where the coolant temperature at the coolant outlet of the chiller is significantly lower than at the coolant inlet of the chiller as a result of a comparatively strong reduction in the volume flow of the coolant that is fed through the chiller. If, in this case, the comparatively cold coolant is fed to the components to be cooled, like for example the storage battery of a motor vehicle, it can result in the individual cells of the storage battery being loaded with coolant that differs significantly in terms of the degree of low temperature. This is because the coolant temperature at the coolant input of the heat exchanger arranged for cooling the storage battery is significantly lower than at the coolant output of the heat exchanger. Accordingly, the first cell arranged near the coolant input of the heat exchanger can be loaded with the comparatively cold coolant from the chiller. The last cell arranged near the coolant output of the heat exchanger can be loaded with coolant that has been heated more strongly by the waste heat of the remaining cells. This temperature span between the first cell and the last cell, viewed in the flow direction of the coolant through the heat exchanger, is disadvantageous.

[0023] A condition which can be particularly well avoided with such a span is that a coolant flow from the chiller merges at the node with another coolant flow which is conducted through another line branch. The provision of the line branch is therefore particularly advantageous for simultaneously gently and still effectively cooling components, like for example the electrical accumulator of a motor vehicle.

[0024] Preferably, at least one heat exchanger is arranged in the coolant circuit, by means of which at least one electrical component of the motor vehicle can be cooled in the cooling operation of the refrigerant circuit. This is based on the insight that by introducing the coolant cooled by means of the chiller into the at least one heat exchanger in the coolant circuit operation, a particularly concentrated and at the same time rapid cooling of the electrical components of the motor vehicle can be achieved by means of the coolant.

[0025] As electrical components of the motor vehicle, for example the electrical accumulator of the motor vehicle can be cooled by means of a heat exchanger arranged at the electrical accumulator. In addition or alternatively, electrical components like for example at least one drive motor and / or power electronics and / or charging devices for charging the electrical accumulator of the motor vehicle can be cooled by means of a corresponding heat exchanger. This is advantageous for the as smooth as possible operation of this type of electrical components of the motor vehicle.

[0026] Preferably, the compressor is designed as an electrically driven refrigerant compressor. Thereby, if the motor vehicle has an internal combustion engine, it is not necessary to operate the internal combustion engine of the motor vehicle to operate the compressor. This is advantageous. Furthermore, a very demand- appropriate refrigerant circuit cooling operation can be achieved by means of the compressor designed as an electrically driven refrigerant compressor.

[0027] In particular in the case of a compressor designed as an electrically driven refrigerant compressor, it can furthermore occur that in the case of a high delivery power of the compressor, the load of the compressor is relatively high. In particular, a high torque load of the electrically driven refrigerant compressor can result in a relatively high current for powering the drive motor of the refrigerant compressor. A high current in turn can result in heating of the refrigerant compressor. And in the case of excessive heating, a reduction in the power output of the compressor or a shutdown of the compressor can result. This situation can be largely avoided at present, since the control device is designed to regulate the coolant flow through the chiller in the cooling operation.

[0028] The motor vehicle according to the application has a cooling device according to the application. Preferably, the motor vehicle is designed as an electric vehicle or a hybrid vehicle. Therefore, it is advantageous in particular in this type of motor vehicle that electrical components of the motor vehicle can be cooled by means of coolant which is conducted through the coolant circuit and is cooled at the chiller.

[0029] In the case of an electrical accumulator of the electric vehicle or the hybrid vehicle being designed as a high-voltage battery, the electrical accumulator has a rated voltage of more than 60 volts and in particular up to several hundred volts.

[0030] In the method for operating a cooling device of a motor vehicle according to the application, the cooling device comprises a refrigerant circuit. A compressor of the refrigerant circuit delivers refrigerant compressed in a cooling operation of the refrigerant circuit to a refrigerant cooler of the refrigerant circuit. An expansion device expands the refrigerant from the refrigerant cooler and loads a chiller arranged downstream of the expansion device with the expanded refrigerant. The chiller is integrated into the refrigerant circuit of the cooling device on the one hand and into the coolant circuit of the cooling device on the other hand. In the cooling operation, heat is transferred from a coolant flow through the chiller to the expanded refrigerant through the chiller in the cooling operation. The cooling device comprises a control device which regulates a coolant flow through the chiller in the cooling operation. Here, the refrigerant pressure present at the suction side of the compressor is regulated by regulating the coolant flow.

[0031] In this way, it can be ensured that the compressor can be operated particularly smoothly even in the event of a high cooling power requirement of the chiller. This is in particular because measures such as, for example, reducing the delivery power of the compressor or even switching off the compressor can largely be avoided because of the refrigerant pressure present at the suction side of the compressor being too high.

[0032] The advantages and preferred embodiments described for the cooling device according to the application apply in a similar manner to the motor vehicle according to the application and to the method according to the application and vice versa.

[0033] Correspondingly, the application also comprises improvements of the method according to the application and of the motor vehicle according to the application, which have the features as already described in connection with the improvements of the cooling device according to the application. For this reason, the respective improvements of the method and of the motor vehicle according to the application are not described again here.

[0034] Preferably, the motor vehicle according to the application is designed as a car, in particular as a passenger car or a utility vehicle, or as a bus.

[0035] The application also comprises combinations of features of the described embodiments. The application therefore also comprises realizations which each have a combination of features of several of the described embodiments, as long as these embodiments are not described as mutually exclusive. BRIEF DESCRIPTION OF DRAWINGS

[0036] Embodiments of the application are described below. The figures show:

[0037] Figure 1A cooling device for a motor vehicle is shown schematically, wherein the cooling device comprises a refrigerant circuit with a chiller, which is integrated into the refrigerant circuit of the cooling device on the one hand and into the coolant circuit of the cooling device on the other hand, wherein a control device of the cooling device is designed to adjust a coolant flow rate through the chiller in a cooling operation of the refrigerant circuit.

[0038] Figure 2 A variant of the coolant circuit is shown locally, wherein the coolant circuit comprises a sub-branch with the chiller and a further line branch.

[0039] Figure 3 A motor vehicle with a cooling device according to Figure 1 or according to Figure 2 is shown highly schematically. DETAILED DESCRIPTION

[0040] The embodiments explained below are preferred embodiments of the application. However, in these embodiments, the individual components of the described embodiments are each a single feature of the application, which can be considered independently of one another, and which also improve the application independently of one another. The disclosure should therefore also include combinations of features other than those of the embodiments shown. Furthermore, the embodiments can also be supplemented by other features of the application.

[0041] In the drawings, identical reference signs denote functionally identical elements.

[0042] The cooling device 10 is shown in Figure 1 , which can be used, for example, in the motor vehicle 12 shown in Figure 3 . The cooling device 10 comprises a refrigerant circuit 14 and a coolant circuit 16, wherein the coolant circuit 16 is shown only highly schematically and locally in Figure 1 . The compressor 18 of the refrigerant circuit 14 is designed to deliver refrigerant compressed in a cooling operation of the refrigerant circuit 14 to a refrigerant cooler 20 of the refrigerant circuit 14. Depending on the refrigerant used, the refrigerant cooler 20 can be designed as a condenser or as a gas cooler in the cooling operation of the refrigerant circuit 14.

[0043] The refrigerant cooled in the refrigerant cooler 20 is expanded by means of an expansion device 22 of the refrigerant circuit 14. Downstream of the expansion device 22, a chiller 24 is arranged in the refrigerant circuit 14, which is integrated into the refrigerant circuit 14 on the one hand and into the coolant circuit 16 on the other hand. The chiller 24 accordingly has a refrigerant inlet 26 and a refrigerant outlet 28. Furthermore, the chiller 24 has a coolant inlet 30 and a coolant outlet 32.

[0044] InFigure 1 In the cooling operation of the refrigerant circuit 14 shown in the middle, heat is transferred from the coolant flow through the chiller 24 to the expanded refrigerant which, in the cooling operation, flows through the chiller 24. Accordingly, heat is introduced into the refrigerant in the chiller 24 and cooling of the coolant takes place.

[0045] In particular, if the chiller 24 is used as the only evaporator in the refrigerant circuit 14 and no additional (not shown here) evaporator is used in addition, the evaporator can be used to cool an air flow which can be introduced into the passenger compartment 34 (see Figure 3 ) of the motor vehicle 12, a relatively high cooling power requirement of the chiller 24 can occur in the cooling operation of the refrigerant circuit 14. In addition, it can occur that there is a high temperature of the ambient air at the refrigerant cooler 20, for example, in the region of the vehicle front end 36 (see Figure 3 ) of the motor vehicle 12, with which the refrigerant cooler 20 is loaded to cool the refrigerant.

[0046] That is, for example, it can occur that the refrigerant cooler 20 is loaded with high-temperature ambient air and the coolant temperature at the coolant inlet 30 of the chiller 24 is also relatively high. In particular in this case, the high cooling power requirement of the chiller 24 can result in a relatively high pressure of the refrigerant at the suction side 38 of the compressor 18. In addition, because the ambient air is very hot, the compressor 18 ensures a relatively strong compression of the refrigerant. As a result, there is refrigerant with a high pressure and thus a high temperature at the pressure side 40 of the compressor 18. Thereby, it is even possible to dissipate the heat of the compressed refrigerant in the refrigerant cooler 20 with the aid of the relatively hot ambient air.

[0047] The regulation of the high pressure at the pressure side 40 of the compressor 18 results in a high pressure ratio in the compressor 18, i.e. in a relatively high value of the quotient which indicates the proportion of the high pressure relative to the suction pressure.

[0048] In the present preferred design of the compressor 18 as an electrically driven refrigerant compressor, in particular in this case it can result in leaving the reliable operating range of the compressor 18. This is because it can result in the compressor 18 being subjected to an undesirably high load, as a result of which the delivery power of the compressor 18 decreases or even the compressor 18 switches off. In the present case, this is avoided.

[0049] This is advantageous. The reason is that, by avoiding a decrease in the delivery power of the compressor 18 and by avoiding the compressor 18 switching off, it can be ensured that the chiller 24 can provide the desired cooling power or refrigeration power.

[0050] To this end, the cooling device 10 has a control device 42 which is designed to regulate the coolant flow through the chiller 24 in the cooling mode. By regulating the coolant flow, the refrigerant pressure present at the suction side 38 of the compressor 18 can be regulated.

[0051] In particular, by controlling or regulating the volume flow of coolant through the chiller 24, the refrigerant pressure present at the suction side 38 of the compressor 18 can be regulated.

[0052] For example, the volume flow of coolant can be controlled or regulated in accordance with the coolant temperature at the coolant inlet 30 of the chiller 24. To this end, the control device 42 can take into account the measurement of a temperature sensor 44 which is shown schematically in Figure 1 . The first temperature sensor 44 is designed to detect the coolant flow temperature at the coolant inlet 30 of the chiller 24.

[0053] Furthermore, a second temperature sensor 46 is shown in Figure 1 which is preferably provided to detect the coolant temperature at the coolant outlet 32 of the chiller 24. This is based on the insight that the heat dissipation of the coolant through the chiller 24 is related, on the one hand, to the temperature difference present between the coolant inlet 30 and the coolant outlet 32 and, on the other hand, to the volume flow of coolant through the chiller 24 in the cooling mode of the refrigerant circuit 14. From these variables, the target cooling power of the chiller 24 can be controlled or regulated very simply.

[0054] Preferably, the control device 42 is designed to take into account, for regulating the coolant flow through the chiller 24 in the cooling mode, a theoretical value of the cooling power which should be provided by the chiller 24 in the cooling mode.

[0055] To regulate the volume flow of coolant conveyed through the chiller 24, the control device 42 can actuate a pump device 48 which belongs to the coolant circuit 16 and is shown in Figure 2 . For the sake of clarity, the pump device 48 is not shown separately in Figure 1 .

[0056] Furthermore, a variant of the coolant circuit 16 is shown in Figure 2 in which the chiller 24 is arranged in a sub-branch 50 of the coolant circuit 16. The sub-branch 50 branches off from another line branch 54 of the coolant circuit 16 at a valve device 52. The valve device 52 can in particular be designed as a three-way valve.

[0057] By manipulating the valve device 52, the control device 42 can cause at least partial opening of the sub-branch 50 in which the chiller 24 is arranged. It can thus in particular be achieved that a first partial flow of coolant is directed through the chiller 24. Preferably, a further partial flow can be directed by means of the valve device 52 through a further pipeline branch 54 to a node 56 of the coolant circuit 16.

[0058] The valve device 52 can in particular be designed as a proportional valve which ensures that a first partial flow of coolant is delivered to the chiller 24 and a further partial flow of coolant flows through the further pipeline branch 54 to the node 56.

[0059] The coolant partial flow from the chiller 24 and the further coolant partial flow which flows through the further pipeline branch 54 can be merged at the node 56. In other words, at the node 56, the first coolant partial flow which is cooled by means of the chiller 24 can be combined with the further partial flow which flows through the further pipeline branch 54. This ensures that the coolant from the node 56 is cooled to a lesser extent than the coolant which is present at the coolant outlet 32, even if the difference in coolant temperature at the coolant outlet 32 relative to the coolant temperature at the coolant inlet 30 is relatively large.

[0060] The merged coolant partial flow can be delivered in the coolant circuit 16 to at least one heat exchanger 58 of the cooling device 10, wherein the at least one heat exchanger 58 is integrated into the coolant circuit 16. By means of the at least one heat exchanger 58, for example, electrical components of the motor vehicle 12 can be cooled. This also applies to the case in which the coolant circuit 16, although it has a coolant pump or pump device 48, does not have a sub-branch 50 and a further pipeline branch 54.

[0061] As an example of electrical components of the motor vehicle 12 which can be cooled by means of the at least one heat exchanger 58, a battery 60 and at least one electric drive 62 of the motor vehicle 12 are schematically shown in Figure 3 The battery 60 can in particular be designed as a high-voltage battery of the motor vehicle 12. And by means of the at least one electric drive 62, preferably, wheels 64 of the motor vehicle 12 can be driven. Accordingly, the motor vehicle 12 can in particular be designed as an electric vehicle or a hybrid vehicle. By cooling the electrical components of the motor vehicle 12 by means of the at least one heat exchanger 58, the electrical components of the motor vehicle 12 can in particular be caused to dissipate heat particularly well.

[0062] In the present case, by manipulating coolant-side actuators, like for example the pump device 48 and / or the valve device 52 which are schematically shown in Figure 2 In the present case, by manipulating coolant-side actuators, like for example the pump device 48 and / or the valve device 52 which are schematically shown in

[0063] The examples show in general how the suction pressure can be adjusted to maintain the operating range of the compressor 18. For this purpose, in a preferably electrically operated motor vehicle 12, the control device 42 can manipulate the coolant volume flow on the evaporator side or on the chiller side, wherein an active cooling of high-voltage components, like for example the electrical accumulator 60 and / or at least one electric drive 62, is achieved.

Claims

1. A cooling device (10) for a motor vehicle (12), the cooling device comprising a refrigerant circuit (14), wherein, The compressor (18) of the refrigerant circuit (14) is designed to deliver the refrigerant compressed during the cooling operation of the refrigerant circuit (14) to the refrigerant cooler (20) of the refrigerant circuit (14). The cooling device has an expansion device (22) for expanding the refrigerant from the refrigerant cooler (20) and a chiller (24) arranged downstream of the expansion device (22). The chiller (24) is integrated into the refrigerant circuit (14) of the cooling device (10) on one hand and into the coolant circuit (16) of the cooling device (10) on the other hand. During the cooling operation, heat can be transferred from the coolant flow through the chiller (24) to the expanded refrigerant flowing through the chiller (24) during the cooling operation. Its features are, The cooling device (10) includes a control device (42) designed to regulate the coolant flow rate of the cross-flow chiller (24) during cooling operation, wherein the refrigerant pressure present on the suction side (38) of the compressor (18) can be regulated by regulating the coolant flow rate.

2. The cooling device (10) according to claim 1. Its features are, The control device (42) is designed to adjust the coolant flow rate by taking into account the measurement value of the temperature sensor (44), wherein the temperature sensor (44) is designed to detect the coolant flow temperature at the coolant inlet (30) of the chiller (24).

3. The cooling device (10) according to any one of the preceding claims. Its features are, The control device (42) is designed to adjust the coolant flow rate based on the theoretical value of the cooling power that should be provided by the chiller (24) during cooling operation.

4. The cooling device (10) according to any one of the preceding claims. Its features are, The control device (42) is designed to operate the pump device (48) to regulate the coolant flow rate, by means of which the coolant can be delivered through the chiller (24).

5. The cooling device (10) according to any one of the preceding claims. Its features are, The chiller (24) is arranged in the secondary branch (50) of the coolant circuit (16), wherein the control device (42) is designed to control the valve device (52) to regulate the coolant flow, wherein the secondary branch (50) can be at least partially opened by controlling the valve device (52).

6. The cooling device (10) according to claim 5. Its features are, The coolant circuit (16) includes another pipeline branch (54), and a secondary branch (50) branches off from the other pipeline branch at a valve device (52), wherein the coolant diversion from the chiller (24) and another coolant diversion flowing through the other pipeline branch (54) can converge at a node (56) of the coolant circuit (16).

7. The cooling device (10) according to any one of the preceding claims. Its features are, At least one heat exchanger (58) is arranged in the coolant circuit (16) so that at least one electrical component (60, 62) of the motor vehicle (12) can be cooled by means of the at least one heat exchanger during the cooling operation of the coolant circuit (14).

8. The cooling device (10) according to any one of the preceding claims. Its features are, The compressor (18) is designed as an electrically driven refrigerant compressor.

9. A motor vehicle having a cooling device (10) according to any one of the preceding claims, wherein, Motor vehicles (12) are designed as electric or hybrid vehicles.

10. A method for using a cooling device (10) for operating a motor vehicle (12), said cooling device comprising a refrigerant circuit (14), wherein, The compressor (18) of the refrigerant circuit (14) delivers the refrigerant compressed during the cooling operation of the refrigerant circuit (14) to the refrigerant cooler (20) of the refrigerant circuit (14), wherein the expansion device (22) expands the refrigerant from the refrigerant cooler, wherein the expanded refrigerant loads a chiller (24) arranged downstream of the expansion device (22), wherein the chiller (24) is integrated into the refrigerant circuit (14) of the cooling device (10) on the one hand, and into the coolant circuit (16) of the cooling device (10) on the other hand, wherein during the cooling operation, heat is transferred from the coolant flow through the chiller (24) to the expanded refrigerant flowing through the chiller (24) during the cooling operation. Its features are, The cooling device (10) includes a control device (42) that regulates the coolant flow rate of the cross-flow chiller (24) during cooling operation, wherein the refrigerant pressure present on the suction side (38) of the compressor (18) is regulated by regulating the coolant flow rate.

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