Air-conditioning system for an electrically drivable motor vehicle, motor vehicle, and method for operating an air-conditioning system

Abstract

The invention relates to an air conditioning system (1) for an electrically driven motor vehicle, comprising: an HVS circuit (5) for conducting a coolant, a traction battery (7) and an evaporator (8) for cooling the traction battery (7) being connected to the HVS circuit; a heating circuit (6) for conducting a coolant for controlling the temperature of the motor vehicle interior, a condenser (16) for outputting heat power being connected to the heating circuit; a cooling circuit (3) for conducting a refrigerant, an evaporator (8), a condenser (16) and a compressor (17) for receiving heat power being connected to the cooling circuit; a heat exchanger (19) which is connected to the HVS circuit (5) and can be controllably connected to the heating circuit (6) and is designed to transfer heat power to the cooling circuit based on the coolant. The invention relates to a control device (32) which is designed to heat the traction battery and / or the interior with the heat output of the condenser (16) by connecting a heat exchanger (19) to the heating circuit (6) so as to transmit at least a portion of the heat output of the condenser (16) to the HVS circuit (5), and to operate the compressor (17) so as to return at least a portion of the heat output of the condenser (16) which is transmitted to the HVS circuit (5) to the evaporator (8) to the heating circuit (6), the heat output occurring at the condenser (16) and which is returned to the heating circuit (6) being increased by the heat output resulting from the operation of the compressor (17).

Description

Technical Field

[0001] The present invention relates to an air conditioning system for an electrically driven motor vehicle. The air conditioning system comprises an HVS circuit for conducting a coolant, to which a traction battery for powering the motor vehicle's electric drive unit and an evaporator for cooling the traction battery are connected. Furthermore, the air conditioning system comprises a heating circuit for conducting a coolant for temperature control of the motor vehicle interior, to which a condenser for discharging heat is connected. Furthermore, the air conditioning system comprises a cooling circuit for conducting a refrigerant, to which an evaporator, a condenser, and a compressor for receiving heat are connected. The present invention further relates to an electrically driven motor vehicle and a method for operating an air conditioning system. Background Art

[0002] Currently, attention is focused on air conditioning systems for electrically driven motor vehicles, namely hybrid vehicles or electric vehicles. These electrically driven motor vehicles have an electric powertrain, which typically includes at least one electric traction engine or electric drive engine and a rechargeable traction battery, such as a high-voltage accumulator, for supplying power to the electric drive engine. Air conditioning systems are used to perform various temperature control tasks in the motor vehicle, namely, to transport or remove heat from various vehicle components. For example, DE 10 2016 213 619 A1 discloses a method for operating an air conditioning system having a refrigeration circuit comprising an evaporator for receiving ambient heat from the environment, a condenser for dissipating heating heat, and a compressor operated with drive power. The refrigeration circuit can be switched between heat pump operation, in which the evaporator receives ambient heat to generate heating heat, and short-circuit operation, in which the condenser and evaporator are thermally short-circuited, so that a portion of the heating heat is supplied to the evaporator as returned heat. In the short-circuit mode, a heating mode is set, in which the remaining heating thermal power is output as effective thermal power for heating the interior of the motor vehicle.

[0003] Temperature control of the traction battery is particularly important for optimal operation of a motor vehicle. For temperature control, i.e., heating and cooling, the traction battery is typically integrated into the HVS circuit of the motor vehicle's air conditioning system. HVS circuits according to the prior art typically have a separate heater for heating the traction battery. Such heaters constitute additional components and therefore increase the cost and installation space required for the motor vehicle's air conditioning system. Summary of the Invention

[0004] The object of the present invention is to provide a thermal system for an electrically driven motor vehicle which is improved compared to the prior art.

[0005] This object is achieved according to the invention by an air-conditioning system, an electrically drivable motor vehicle, and a method for operating an air-conditioning system.

[0006] An air conditioning system for an electrically driven motor vehicle according to the present invention includes an HVS circuit for conducting coolant, a traction battery for powering the motor vehicle's electric drive unit, and an evaporator for cooling the traction battery connected to the HVS circuit. The air conditioning system also includes a heating circuit for conducting coolant for controlling the temperature of interior air in the motor vehicle interior, and a condenser for discharging heat power connected to the heating circuit. The air conditioning system also includes a cooling circuit for conducting coolant, an evaporator for receiving heat power, a condenser, and a compressor connected to the cooling circuit. The air conditioning system also includes a heat exchanger connected to the heating circuit and controllably connectable to the HVS circuit, and designed to transfer heat power from the heating circuit to the HVS circuit based on the coolant. To heat the traction battery and / or the interior using the heat power of the condenser, a control unit of the air conditioning system is designed to connect the heat exchanger to the heating circuit, creating a thermal short between the condenser and the evaporator, so as to transfer at least a portion of the heat power of the condenser to the HVS circuit. Furthermore, the control device is designed to operate the compressor for heating the traction battery and / or the interior in order to return at least a portion of the heating power of the condenser, which is transferred to the evaporator via the heat exchanger, to the heating circuit, wherein the heating power occurring at the condenser and returned to the heating circuit is increased by the heating power resulting from the operation of the compressor.

[0007] The present invention also includes a method for operating an air conditioning system according to the present invention. Here, to heat the traction battery and / or the interior, a heat exchanger is connected to the heating circuit, forming a thermal short between the condenser and the evaporator, so as to transfer at least a portion of the condenser's heating power to the HVS circuit. Furthermore, the compressor is operated to return at least a portion of the condenser's heating power, which was transferred to the HVS circuit at the evaporator, to the heating circuit, wherein the heating power generated at the condenser and returned to the heating circuit is increased by the heating power resulting from the operation of the compressor.

[0008] The present invention further relates to an electrically driven motor vehicle comprising an air conditioning system according to the present invention. The motor vehicle is in particular designed as a passenger car. The motor vehicle has an electric drivetrain with a rechargeable traction battery or traction accumulator, such as a high-voltage accumulator, and an electric drive unit. The electric drive unit in particular comprises at least one electric traction machine and / or corresponding power electronics, such as at least one inverter and / or a charger.

[0009] An air conditioning system is designed for use in a motor vehicle. The air conditioning system can be operated in different operating modes, namely different heating modes and different cooling modes. These different operating modes can be provided by a control unit for the air conditioning system. The control unit can be integrated into one or more controllers of the motor vehicle.

[0010] The air conditioning system includes an HVS circuit and a heating circuit. The HVS circuit and the heating circuit are components of the overall cooling circuit of the air conditioning system. The overall cooling circuit circulates a coolant and, for this purpose, includes, in particular, corresponding piping and at least one pump. The coolant is preferably a water / glycol mixture. The air conditioning system also includes a refrigeration circuit, which circulates a refrigerant and is thermally coupled to the overall cooling circuit.

[0011] The HVS circuit includes a traction battery and an evaporator, which can absorb and remove heat output by the traction battery to cool it. The evaporator is designed to transport this heat to the refrigeration circuit via a compressor. The heating circuit, which is used to temperature-control the air in the interior of the vehicle or the passenger compartment, can also include a heating device. This heating device can, in particular, include a heater, such as an electric continuous-flow heater, and / or a heating heat exchanger. Furthermore, a heating circuit pump is provided in the heating circuit to convey the circulating coolant. Furthermore, a condenser, such as a water-cooled condenser, is connected to the heating circuit and can, together with the evaporator and compressor, perform a heat pump function.

[0012] The refrigeration circuit can be operated in heat pump mode. During this mode, heat power from the HVS circuit is transferred to the heating circuit via the compressor of the refrigeration circuit. In heat pump mode, heat power is received by the evaporator. This heat power can be, for example, ambient heat power, heat power from the electric drive unit, heat power from the traction battery, or other heat power transferred to the HVS circuit. Ambient heat power can be, for example, heat received from the vehicle's surroundings by the ambient cooler. Heat power from the electric drive unit can be, for example, waste heat from the electric motor, inverter, or charger. Heat power from the traction battery can be, for example, waste heat from the traction battery. This heat power, together with the drive power supplied to the compressor to operate it, is transferred to the heating circuit as effective heat power, for example, to heat the interior. In other words, the effective heat power output by the condenser is derived from the heat power of the evaporator and the drive power of the compressor.

[0013] The refrigeration circuit can also be operated in short-circuit mode. This short-circuit mode can be provided whenever additional heating or cooling power is required to heat the traction battery and / or the interior. To this end, the evaporator and condenser are thermally short-circuited by connecting the heat exchanger of the HVS circuit to the heating circuit. In particular, the heating circuit has a valve device via which the heat exchanger can be controllably connected to the heating circuit. In this short-circuit mode, at least a portion of the cooling power transferred to the heating circuit and output by the condenser is returned to the heat exchanger and thereby to the HVS circuit, where it is at least partially taken over again by the evaporator. The heat exchanger is preferably arranged in the HVS circuit directly upstream of the evaporator. In this way, the cooling power returned to the HVS circuit can be directly taken over again by the evaporator with virtually no losses.

[0014] In short-circuit operation, the compressor and refrigeration circuit are operated, in particular, so that the maximum possible drive power is supplied to the compressor. To this end, the control device is specifically designed to supply the drive power to the compressor. In particular, the drive power supplied to the compressor is such that the compressor has a particularly high heat release and thereby provides a particularly high thermal output. This compressor thermal output is added to the thermal power flow between the evaporator and condenser. In other words, in short-circuit operation, the additional effective thermal power generated at the condenser is generated using the compressor drive power. In other words, the thermal output at the condenser is increased by short-circuit operation. This increased thermal power can be at least partially transferred back to the HVS circuit, where it can be used to heat the traction battery and can be transferred back to the heating circuit via the refrigeration circuit to further increase the thermal output. Alternatively, or additionally, the increased thermal power can be used to heat the interior. In other words, when the condenser and evaporator are thermally short-circuited, the compressor drive power is used as additional thermal power to heat the traction battery and / or the interior.

[0015] In particular, the control device is designed to thermally short-circuit the condenser and evaporator and operate the compressor if the temperature of the coolant in the HVS circuit is below a predetermined threshold value. This allows the condenser's heat output, which was transferred to the HVS circuit, to be additionally directed back to the evaporator for heating. This also provides for short-circuit operation, allowing the evaporator's temperature to be reached more quickly in a temperature range that is advantageous for heat pump operation. By directing the heat output of the condenser and the heating device back into the HVS circuit, the evaporator can be heated, for example, and thus placed in an operating state in which heat pump operation can be efficiently achieved.

[0016] In other words, in the method, the compressor is used as a heat source for heating the interior and / or the traction battery during short-circuit operation of the condenser and evaporator. This means that the heat source already present in the air conditioning system can also be used to heat the traction battery and / or the interior. This advantageously eliminates the need for an additional heater in the HVS circuit, which would be sufficient for only one operating mode, namely heating the traction battery. Although a heat exchanger is required instead of a separate heater, it can provide for numerous other operating modes, such as cooling the traction battery by dissipating heat from the HVS circuit to the heating circuit.

[0017] It has proven advantageous if the control unit is designed to connect a heat exchanger to the heating circuit for heating the traction battery, so as to transfer at least a portion of the thermal power of the heating device of the heating circuit to the HVS circuit, thereby connecting the heating device to the HVS circuit. In other words, by connecting the HVS circuit to the heating circuit, the heating device of the heating circuit is also thermally coupled to the HVS circuit. In this way, the thermal power provided by the heating device of the heating circuit can not only be used to heat the interior, but can also be fed into the HVS circuit via the heat exchanger, where it is used to heat the traction battery. In other words, another heat source already present in the air conditioning system, namely the heating device of the heating circuit, can be used to heat the traction battery.

[0018] It has also proven advantageous if the air conditioning system includes a cooling circuit for conducting coolant, to which the electric drive unit of the motor vehicle is connected, and which is fluidically coupled to the HVS circuit. The control unit is configured to additionally connect the cooling circuit to the HVS circuit for heating the traction battery and / or the interior, so as to transfer at least a portion of the electric drive unit's thermal output to the HVS circuit. The thermal output of the electric drive unit used to heat the traction battery represents heat loss from the electric drive unit. The cooling circuit is also part of an overall cooling circuit and is configured to circulate a coolant. The cooling circuit includes the electric drive unit, which may include at least one drive engine, power electronics, a charger, etc. To cool the drive unit, an ambient cooling device including at least one ambient cooler may be connected to the cooling circuit. The drive unit of the cooling circuit can be connected to the HVS circuit via a valve device controllable by the control unit and used as an additional heat source. The valve device may, for example, include two three-way valves, which allow the coolant to be divided between the HVS circuit and the cooling circuit. The lost heat output by the drive unit is fed into the HVS circuit as thermal power via the coolant. This lost heat can be output, for example, during normal operation of the drive unit. In this normal operation, the drive unit operates efficiently and therefore outputs minimal lost heat. In the traction battery heating mode, the three heat sources are operated simultaneously by the control unit, in particular at least temporarily, to provide thermal power.

[0019] The control device is preferably designed to operate the electric drive unit in a low-efficiency operating mode to increase the amount of heat dissipation. In this low-efficiency operating mode, the drive unit outputs a higher power loss than the minimum power loss and can thereby provide a higher heating or heating power for the traction battery. In other words, heating of the traction battery in the HVS circuit is achieved by targeted reduction in the efficiency of the electric drive system. For example, only a portion of the heating power of the electric drive unit can be supplied to the traction battery. The remainder of the heating power of the drive unit can be transferred from the HVS circuit to the heating circuit via a heat exchanger and used there to heat the interior.

[0020] In this case, it can be provided that the control unit is designed to divide the heating power of the condenser between the traction battery and the interior for heating the interior. In other words, the heating power output by the condenser can be used simultaneously for heating the interior and for heating the traction battery. This ensures both interior comfort for the vehicle's passengers and optimal temperature control of the traction battery.

[0021] In a further development of the invention, the control device is designed to control the portion of the heating power transferred from the heating circuit to the HVS circuit by means of a valve device of the heating circuit, to which the heat exchanger can be connected via the valve device. The valve device is, in particular, a three-way valve, which can be used to decouple the heat exchanger from the heating circuit so that the heat exchanger is not located in the flow path of the coolant circulating in the heating circuit. The heat exchanger can also be integrated into the flow path via the three-way valve in such a way that only a portion of the coolant transporting the heating power of the condenser and compressor flows through the heat exchanger, thereby dividing the heating power between the interior and the traction battery.

[0022] Particularly preferably, the control device is designed to heat the traction battery during a charging operation of the traction battery. During this charging operation, in which the traction battery is connected, for example, to a charging device external to the vehicle, heating of the interior is generally not necessary, so that the entire heating power of the heating circuit, for example, including the heating power of the condenser or evaporator and the heating power of the heater, can be transferred to the HVS circuit for heating the traction battery.

[0023] In another embodiment, the control unit is designed to connect a heat exchanger to the HVS circuit and the heating circuit for cooling the traction battery. This allows the coolant for the evaporator to be precooled by transferring heat from the HVS circuit to the heating circuit. In other words, the heat exchanger is also connected to the HVS circuit and the heating circuit in the traction battery cooling mode. This allows the heat from the traction battery to be dissipated via the evaporator and the heat exchanger. The heat exchanger also precools the coolant for the evaporator, thereby assisting the evaporator in cooling. By assisting evaporation during traction battery cooling, a more dynamic driving range for the vehicle can be advantageously achieved.

[0024] The embodiments described with respect to the air-conditioning system according to the invention and their advantages apply correspondingly to the motor vehicle according to the invention and the method according to the invention.

[0025] The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned subsequently in the description of the figures and / or shown individually in the figures can be used not only in the respectively indicated combination but also in other combinations or individually. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The invention will now be explained in more detail using preferred exemplary embodiments and with reference to the accompanying drawings.

[0027] In the attached figure:

[0028] Figure 1 A schematic diagram showing an embodiment of an air-conditioning system according to the present invention;

[0029] Figure 2 Shown in accordance with Figure 1 the air conditioning system in heating mode of the traction battery; and

[0030] Figure 3 Shown in accordance with Figure 1 Air conditioning system in cooling mode for the traction battery. DETAILED DESCRIPTION

[0031] In the figures, identical elements and elements with the same function are provided with the same reference symbols.

[0032] Figure 1 An embodiment of an air conditioning system 1 for an electrically driven motor vehicle (not shown here) is shown. The air conditioning system 1 has a main cooling circuit 2 for conducting a coolant and a refrigeration circuit 3 for conducting a coolant. The air conditioning system 1 can be operated in different operating modes, for which Figure 2 and Figure 3 An embodiment is shown in FIG.

[0033] The overall cooling circuit 2 comprises a cooling circuit 4, an HVS circuit 5, and a heating circuit 6. The HVS circuit 5 comprises a traction battery 7 of the motor vehicle and an evaporator 8 for cooling the traction battery 7. The evaporator 8 is also connected to the refrigeration circuit 3 of the air conditioning system 1. Furthermore, the HVS circuit 5 comprises an HVS pump 9, an HVS shutoff valve 10 upstream of the traction battery 7, and an HVS check valve 11 downstream of the traction battery 7. The HVS shutoff valve 10 and the HVS check valve 11 fluidically seal the traction battery 7. In particular, the HVS circuit 5 does not comprise a separate heater for heating the traction battery 7. In other words, the HVS circuit 5 is designed to be non-heated.

[0034] The heating circuit 6, which is configured for air conditioning the interior of a motor vehicle, includes a heating device 12, which is configured to heat the interior air. The heating device 12 includes a heating heat exchanger 13 and a heater 14. The heating heat exchanger 13 can also remove heat from the interior for cooling. The heater 14 can be configured, for example, as an electric continuous flow heater (EDH). The heating circuit 6 also includes a heating circuit pump 15 and a condenser 16. The condenser 16 is also connected to the refrigeration circuit 3. The refrigeration circuit 3 also includes a compressor 17 and an expansion valve 18. The refrigeration circuit 3 can be operated in heat pump mode, in which thermal power can be transferred from the HVAC circuit 5 to the heating circuit 6 by operating the evaporator 8, the compressor 17, and the condenser 16.

[0035] The HVS circuit 5 and the heating circuit 6 can also be coupled via a heat exchanger 19. For this purpose, a valve device 20 in the form of a three-way valve is provided in the heating circuit 6, via which the heat exchanger 19 connected to the HVS circuit 5 can also be connected to the heating circuit 6. The heat exchanger is here arranged upstream of the evaporator 8, in particular directly upstream of the evaporator 8.

[0036] The cooling circuit 4 includes an electric drive unit 21 of a motor vehicle. The electric drive unit 21 includes, for example, at least one electric drive engine and power electronics. Furthermore, the cooling circuit 4 includes an ambient cooler device 22 for exchanging heat with the motor vehicle's environment. The ambient cooler device 22 allows the electric drive unit 21 to be cooled during operation. The ambient cooler device 22 includes a first ambient cooler 23, a second ambient cooler 24, a ventilator 25, and a compensating tank 26. The two ambient coolers 23 and 24 are arranged one after the other in an ambient air path 27, with the second ambient cooler 24 being downstream of the first ambient cooler 23 in terms of coolant and upstream of the first ambient cooler 23 in the ambient air path 27. The first ambient cooler 23 may be, for example, an HT cooler, or high-temperature cooler. The second ambient cooler 24 may be, for example, an NT cooler, or low-temperature cooler. A cooler coolant flows through the second ambient cooler 24 than through the first ambient cooler 23. A fan 25 for sucking in ambient air is provided in the ambient air path 27 downstream of the two ambient coolers 23 , 24 . The cooling circuit 4 also has a cooling circuit pump 28 for conveying the coolant in the cooling circuit 4 .

[0037] The cooling circuit 4 and the heating circuit 6 can be fluidically coupled via a shutoff valve 29. Thus, the heating circuit 6 can be connected to the ambient cooling device 22 of the cooling circuit 4 for cooling the interior. To this end, heat is transported from the interior via the heating heat exchanger 13 into the heating circuit 6 and dissipated to the ambient cooling device 22. Furthermore, the cooling circuit 4 and the HVS circuit 5 can be fluidically coupled via a three-way valve 30 upstream of the drive unit 21 and a three-way valve 31 downstream of the drive unit 21. The three-way valves 30 and 31 allow the electric drive unit 21 to be connected to the HVS circuit 5. A control device 32 of the air conditioning system 1 forms a component for operating the air conditioning system 1.

[0038] exist Figure 2 and Figure 3 The different operating modes of the air conditioning system 1 are shown in FIG. In this case, the active paths in the respective operating mode are shown in bold. Figure 2shows an operating mode in the form of a heating mode for the traction battery 7 . In heating mode, at least a portion of the heating power of the condenser 16 , the heater 12 , and the electric drive unit 21 is supplied to the traction battery 7 . To feed the heating power of the electric drive unit 21 into the HVS circuit 5 , the control unit 32 switches the three-way valves 30 and 31 to the open state. In this open state, at least a portion of the coolant circulating in the cooling circuit 4 flows into the HVS circuit 5 . This coolant transports the heat in the form of heat loss from the electric drive unit 21 . The coolant flows from the drive unit 21 through the three-way valve 31 into the HVS circuit 5 . There, the coolant flows through the heat exchanger 19 , the evaporator 8 , and the traction battery 7 to the three-way valve 30 , and from there back into the cooling circuit 4 to the drive unit 21 . To increase the heat loss of the electric drive unit 21 and thereby increase the heating power for the traction battery 7 , the control unit 31 can, for example, operate the drive unit 21 in an inefficient, power-loss-increasing operating mode.

[0039] The heating power of the heating device 12 and the condenser 16 is transferred from the heating circuit 6 to the HVS circuit 5 via the heat exchanger 19. To this end, the control device 31 connects the heat exchanger 19 to the heating circuit 6 via the three-way valve 20. The three-way valve 20 is switched on, allowing at least a portion of the coolant to flow through the heat exchanger 19. Furthermore, the control device 31 activates the heating device 12, particularly the heater 14, to generate heating power. This heating power is at least partially transferred as thermal power to the HVS circuit 5 via the heat exchanger 19. The remainder of the heating power of the heating device 12 can be used to heat the interior.

[0040] Furthermore, by connecting the heat exchanger 19 to the heating circuit 6 and the HVS circuit 5, the evaporator 8 and the condenser 16 are thermally short-circuited. In other words, the refrigeration circuit 3 is operated in short-circuit mode. In this short-circuit mode, the control unit 31 operates the compressor 17. To this end, an increased drive power is supplied to the compressor 17. This increased drive power of the compressor 17 is converted into thermal power, which is applied to the condenser 16. The thermal power generated by the compressor 17 and applied to the condenser 16 is also at least partially fed into the HVS circuit 5 via the heat exchanger 19, for example, to heat the traction battery 7 on the one hand and to transfer a portion of the thermal power back to the heating circuit 6 via the refrigeration circuit 3 on the other. When the thermal power is transferred to the heating circuit via the refrigeration circuit 6, the thermal power of the compressor 17 is added to the thermal power, so that the increased thermal power is applied to the condenser 16. That is, by feeding back heating power from the heating circuit 6 into the HVS circuit 5 and transporting at least a portion of the fed-back heat back into the heating circuit 6 via the refrigeration circuit 3, the heating power generated at the condenser 16 can be increased. This increased heating power can be at least partially fed back into the HVS circuit 5 again via the heat exchanger 19. A portion of the heating power generated at the condenser 16 can also remain in the heating circuit 6 and be used there to heat the interior.

[0041] This short-circuit operation is particularly advantageous at low ambient temperatures, when heat pump operation cannot be provided or cannot be provided efficiently due to insufficient operational readiness of evaporator 8. Such insufficient operational readiness of evaporator 8 can be caused, for example, by ice formation on evaporator 8. In other words, in short-circuit operation, the drive power of compressor 17 can be used as heating power for heating traction battery 7. In other words, traction battery 7 can be heated in heating mode by three heat sources: drive unit 21, heater 12, and condenser 16 or compressor 17. The interconnection of these heat sources with traction battery 7 in air-conditioning system 1 can also prevent unnecessary heating of other components of air-conditioning system 1.

[0042] exist Figure 3 shows an operating mode in the form of a cooling mode for the traction battery 7 . In cooling mode, the traction battery 7 is cooled by the evaporator 8 , by circulating a coolant in the HVS circuit 5 and transferring waste heat from the traction battery 7 to the evaporator 8 . Furthermore, a heat exchanger 19 is connected to the HVS circuit 5 and the heating circuit 6 by the control unit 31 . This heat exchanger 19 allows heat energy to be transferred from the HVS circuit 5 to the heating circuit 6 , thereby pre-cooling the coolant for the evaporator 8 . The heat energy transferred to the heating circuit 6 can be dissipated, for example, via an ambient cooler device 22 . For this purpose, the heating circuit 6 is fluidically coupled to the cooling circuit 4 via a shutoff valve 29 .

Claims

1. An air conditioning system (1) for an electrically driven motor vehicle, comprising: A coolant-carrying HVS circuit (5), to which a traction battery (7) for supplying power to an electric drive unit (21) of a motor vehicle and an evaporator (8) for cooling the traction battery (7) are connected, A heating circuit (6) for conducting a coolant for controlling the temperature of the interior of a motor vehicle, to which a condenser (16) for outputting heat power is connected, A refrigeration circuit (3) for introducing a refrigerant, an evaporator (8) for receiving heat power, the condenser (16) and a compressor (17) are connected to the refrigeration circuit, It is characterized by: a heat exchanger (19) which is connected to the HVS circuit (5) and which can be controllably connected to the heating circuit (6) and is designed to transfer heat power from the heating circuit (6) to the HVS circuit (5) on the basis of a coolant, and A control device (32) is designed to heat the traction battery and / or the interior with the heat output of the condenser (16) by connecting the heat exchanger (19) to the heating circuit (6) while forming a thermal short between the condenser (16) and the evaporator (8) so as to transfer at least a portion of the heat output of the condenser (16) to the HVS circuit (5), and to operate the compressor (17) so as to return at least a portion of the heat output of the condenser (16) transferred to the HVS circuit (5) to the evaporator (8) to the heating circuit (6), wherein the heat output occurring at the condenser (16) and returned to the heating circuit (6) is increased by the heat output caused by the operation of the compressor (17).

2. The air conditioning system (1) according to claim 1, It is characterized by: The heat exchanger (19) is arranged in the HVS circuit (5) directly upstream of the evaporator (8).

3. The air conditioning system (1) according to claim 1 or 2, It is characterized by: The heating circuit has a heating device for providing heating power, wherein the control device (32) is designed for heating the traction battery (7) to connect a heat exchanger (19) to the heating circuit (6) in order to transfer at least a portion of the heating power of the heating device (12) to the HVS circuit (5), thereby connecting the heating device (12) to the HVS circuit (5).

4. The air conditioning system (1) according to claim 1 or 2, It is characterized by: The air conditioning system (1) has a cooling circuit (4) for conducting a coolant, to which an electric drive unit (21) of a motor vehicle is connected, and the cooling circuit can be fluidically coupled to an HVS circuit (5), wherein the control device (32) is designed to heat the traction battery (7) by additionally connecting the cooling circuit (4) to the HVS circuit (5) in order to transfer at least a portion of the thermal power of the electric drive unit (21) to the HVS circuit (5), wherein the thermal power of the electric drive unit (21) is the lost heat of the electric drive unit (21).

5. The air conditioning system (1) according to claim 4, It is characterized in that The control device (32) is designed to operate the electric drive unit (21) in a low-efficiency operating mode in order to increase the outputted lost heat.

6. The air conditioning system (1) according to claim 1 or 2, It is characterized in that The control device (32) is designed to divide the heating power of the condenser (16) between the traction battery (7) and the interior.

7. The air conditioning system (1) according to claim 1 or 2, It is characterized in that The heat exchanger (19) is connected to the heating circuit (6) via a valve device (20), wherein the control device (32) is designed to control the portion of the heating power transmitted from the heating circuit (6) to the HVS circuit (5) by means of the valve device (20).

8. The air conditioning system (1) according to claim 1 or 2, It is characterized in that The control device (32) is designed to thermally short-circuit the condenser (16) and the evaporator (8) and to operate the compressor (17) if the temperature of the coolant in the HVS circuit (5) is less than a predetermined threshold value, so that the thermal power of the condenser (16) transmitted to the HVS circuit (5) is additionally designed to heat the evaporator (8).

9. The air conditioning system (1) according to claim 1 or 2, It is characterized in that The control device (32) is designed to prepare the traction battery (7) during a charging operation of the traction battery (7).

10. The air conditioning system (1) according to claim 1 or 2, It is characterized in that The control device (32) is designed to connect a heat exchanger (19) to the HVS circuit (5) and the heating circuit (6) for cooling the traction battery (7) in order to precool the coolant for the evaporator (8) by transferring heat power from the HVS circuit (5) to the heating circuit (6). 11 . An electrically driven motor vehicle comprising an air conditioning system ( 1 ) according to claim 1 .

12. Method for operating an air-conditioning system (1) according to one of claims 1 to 10, wherein: To heat the traction battery and / or the interior using the thermal power of the condenser (16): The heat exchanger (19) is connected to the heating circuit (6) so as to form a thermal short circuit between the condenser (16) and the evaporator (8) in order to transfer at least part of the heating power of the condenser (16) to the HVS circuit (5), and The compressor (17) is operated in order to return at least a portion of the thermal power of the condenser (16) which is transferred to the HVS circuit (5) to the evaporator (8) to the heating circuit (6), wherein the thermal power occurring at the condenser (16) and which is returned to the heating circuit (6) is increased by the thermal power resulting from the operation of the compressor (17).

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