Method and system for temperature management in a vehicle

Abstract

The invention relates to a method for temperature management in a vehicle, in particular a battery-electric vehicle, the vehicle comprising a coolant circuit for transporting coolant, wherein the coolant circuit is thermally coupled to at least a first heat exchanger and a second heat exchanger, a refrigerant circuit for transporting refrigerant, wherein the refrigerant circuit is thermally coupled to at least the first heat exchanger and the second heat exchanger and has a compressor for compressing the refrigerant, the method comprising the steps: S1. compressing the refrigerant in the compressor by raising a temperature level of the refrigerant; S2. conveying the refrigerant in the refrigerant circuit from the compressor via at least the first heat exchanger and the second heat exchanger back to the compressor; S3.conveying the coolant at least from the first heat exchanger to the second heat exchanger and back to the first heat exchanger; S4. wherein, in heating operation, heat is transferred from the refrigerant at the first heat exchanger to the coolant and heat is transferred from the coolant at the second heat exchanger to the refrigerant. The invention further relates to a temperature management system for a vehicle, in particular a battery-electric vehicle.

Description

The invention relates to a method for temperature management in a vehicle and to a temperature management system for a vehicle. The vehicle is in particular a battery-electrically driven vehicle.Prior ArtThe energy management of battery-electrically driven vehicles (BEV=Batury electrical vehicles for short) has an essential significance in the efficient use of the available electrical energy in order to maximize the range for driving as far as possible and at the same time to meet the requirements for component service life and passenger comfort.In this context, the coordinated thermal management of the drive train together with the temperature conditioning of the passenger cabin plays an important role in optimizing this goal in the overall system. A requirement here may be that the passenger cabin must be heated at low external temperatures in order to ensure the thermal comfort of the passengers. If a heat pump is installed in the vehicle for increasing efficiency for this purpose, the heat pump can draw the heat from a heat source via an evaporator arranged upstream of a compressor via a refrigerant circuit and can emit the heat from a heat sink via a condenser arranged downstream of the compressor.Prior to the heat emission, the vaporized refrigerant is brought to a higher temperature level by raising the pressure via the compressor, in order to thus achieve a higher heat emission. The pressure is then released again to the initial level.A disadvantage of the heat pump is that the efficiency decreases significantly with colder external temperatures and the necessary electrical power thereby increases with the difference from the setpoint temperature. In addition, the heat pump can normally only be operated up to the temperature range at which the evaporation point of the refrigerant used can just be adjusted (for example -5 to -10° C.).Therefore, for extreme low temperatures in the prior art, additional electrical heating elements ("positive temperature coefficient" or PTC heater) are often installed in order to be able to heat the air of the passenger cabin still.For reasons of, among other things, the energy efficiency of the temperature management system and the additional costs and a loss of available construction space in the vehicle, the possibly sole use of electric heating elements is to be considered problematic.It is an object of the invention to specify an alternative or an improved method for temperature management in a vehicle which is in particular battery-electrically driven, and a temperature management system for a vehicle which is in particular battery-electrically driven.Disclosure of the InventionThe object of the invention is achieved by means of a method according to claim 1 and by means of a temperature management system according to claim 8.According to a first aspect, the present disclosure discloses a method for temperature management in a vehicle, in particular a battery-electrically driven vehicle, the vehicle comprising a coolant circuit for transporting coolant, wherein the coolant circuit is thermally coupled to at least a first heat exchanger and a second heat exchanger, a refrigerant circuit for transporting refrigerant, wherein the refrigerant circuit is thermally coupled to at least the first heat exchanger and the second heat exchanger and has a compressor for compressing the refrigerant, the method comprising the steps of:S 1 compresses the refrigerant in the compressor to raise a temperature level of the refrigerant;S2 conveys the refrigerant in the refrigerant circuit from the compressor via at least the first heat exchanger and the second heat exchanger back to the compressor;S 3 conveys the coolant at least from the first heat exchanger to the second heat exchanger and back to the first heat exchanger;S 4. wherein, in a heating operation, heat from the refrigerant is transferred to the coolant at the first heat exchanger and heat from the coolant is transferred to the refrigerant at the second heat exchanger.Within the scope of the invention, the arabic numerals in the designation of the method steps "S 1" to "S 4" serve merely for identifying the individual steps; no sequence of the method steps is intended to be defined thereby. It is thus possible for step S 3 to be carried out before step S 1, for example. In particular, some or more of steps S 1 to S 4 can also be carried out in parallel or repeatedly in a loop.In step S 3, heat can be emitted from the coolant, if necessary and / or partially, to one or more further heat sinks, which are thermally coupled to the coolant circuit, for example to a vehicle battery or to a passenger cabin.In step S 3, heat can be taken from a vehicle environment using an ambient heat exchanger and be released to the coolant.In step S 3, heat can be generated with an electric heating element and be emitted to the coolant.In step S 3, heat from waste heat of a drive unit of the vehicle may be dissipated to the coolant.In step S 2, heat can be emitted from the refrigerant, if necessary and / or partially, to one or more further heat sinks, which are thermally coupled to the refrigerant circuit, for example to a condenser for heating an operator's cab of the vehicle or for heating a refrigerant-cooled battery.In step S 2, heat from one or more heat sources can be emitted to the refrigerant, for example ambient heat, waste heat from the compressor, or from additional electrical heating elements.Steps S 1 to S 4 may be performed until a temperature of the refrigerant at an outlet of the compressor reaches a predetermined value.According to a second aspect, the present disclosure discloses a temperature management system for a vehicle, in particular a battery-electrically driven vehicle, comprising:a refrigerant circuit for guiding a refrigerant, comprising at least one compressor and a refrigerant delivery pump;a coolant circuit for guiding a coolant, wherein the coolant circuit is thermally coupled to a battery of the vehicle and comprises at least one coolant delivery pump, the coolant circuit having one or more valves for conducting the coolant as required;a first heat exchanger, in particular a liquid cooled condenser (LCC), thermally coupled to both the refrigerant circuit and the coolant circuit;a second heat exchanger, in particular a battery cooler, which is thermally coupled both to the refrigerant circuit and to the coolant circuit and is arranged behind the first heat exchanger and in front of the compressor with respect to a flow direction of the refrigerant in a heating operation;a controller which is connected in terms of control technology to the coolant delivery pump, the refrigerant delivery pump and the one or more valves of the coolant circuit and is configured to carry out the method according to claim 1.The coolant circuit can be thermally coupled to an ambient heat exchanger, via which heat is taken from a vehicle environment and supplied to the coolant.The refrigerant circuit may be thermally coupled to a condenser for heating an operator cabin of the vehicle, the condenser being disposed rearward of the compressor with respect to a flow direction of the refrigerant.The coolant circuit can comprise a four-way valve, which can be controlled by the controller as required and has two inputs and two outputs, wherein:a first inlet is fluidically connected to the first heat exchanger and a first outlet is connected to the second heat exchanger;a second input receives a flow of coolant from the direction of thermal coupling to the battery.The second heat exchanger can be arranged fluidically between the four-way valve and a first three-way valve, wherein the first three-way valve conducts a coolant flow as required in the direction of the thermal coupling to the battery and / or in the direction of the first heat exchanger.A second three-way valve can be arranged fluidically between the first three-way valve and the first heat exchanger, wherein the second three-way valve directs a coolant flow coming from the first three-way valve directly to the first heat exchanger as required and / or directs it via the ambient heat exchanger to the first heat exchanger.A second outlet of the four-way valve may be fluidically connected to a third three-way valve, wherein the third three-way valve directs a coolant flow coming from the four-way valve as required in the direction of the thermal coupling to the battery and / or in the direction of the second three-way valve.The coolant circuit may be thermally coupled to an electrical heating element between the four-way valve and the third three-way valve. An electric heating element may be thermally coupled to the coolant circuit at the first heat exchanger.The coolant circuit may include a five-way valve and a four-way valve, wherein:the first heat exchanger is arranged fluidically between a first outlet of the five-way valve and a first inlet of the four-way valve;the second heat exchanger is fluidically arranged between a first outlet of the four-way valve and a first inlet of the five-way valve; andthe thermal coupling to the battery is arranged between a second output of the five-way valve and a second input of the four-way valve.A third outlet of the five-way valve may be fluidly connected to an ambient heat exchanger disposed between the five-way valve and the first heat exchanger.The coolant circuit may be thermally coupled to an electrical heating element between a second output of the four-way valve and a second input of the five-way valve.An electric heating element may be thermally coupled to the coolant circuit at the first heat exchanger.Brief Description of the FiguresThe invention is explained in more detail below on the basis of exemplary embodiments with reference to the appended schematic drawing, which is not true to scale. In the invention, a feature may be positive, i.e. present, or negative, i.e. absent. In this specification, a negative feature is not explicitly explained as a feature unless the invention claims the absence thereof. That is, the invention actually made, rather than one constructed by the prior art, is to omit this feature. The absence of a feature (negative feature) in an embodiment shows that the feature is optional. - In the merely exemplary figures (FIG.) of the drawing, FIG. 1 schematically shows the structure and the mode of operation of a heat pump according to the prior art; FIG. 2 schematically shows the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention; FIG. 3 ashows schematically the structure and the functioning of a temperature management system for a vehicle according to an embodiment of the invention; FIG. 3 bschematically illustrates the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention; FIG. 4 schematically shows the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention, on a coolant side; FIG. 5 schematically shows the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention, on a coolant side; FIG. 6 schematically shows the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention; FIG. 7 schematically shows the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention;DESCRIPTION OF THE INVENTIONFIG. 1 schematically shows the structure and the mode of operation of a heat pump 1 according to the prior art. In a refrigerant circuit 7, refrigerant is conveyed by a not-shown refrigerant pump. The refrigerant comprises in particular propane (R290) and / or CO2(R744).In this case, the heat pump 1 draws heat from a heat source 5 via an evaporator 3 and emits said heat at a heat sink 6 via a condenser 4. Before the heat emission at the condenser 4, the refrigerant evaporated at the evaporator 3 is first brought to a higher temperature level by raising the pressure via an electric compressor 2, in order to achieve a higher heat emission in this way. Subsequently, the pressure is expanded again to the initial level, typically by an electronically controlled expansion valve 8.With reference to FIG. 2, the structure and the mode of operation of a temperature management system 10 according to the invention for a vehicle is explained schematically below, in which the principle of the heat pump is used. In the embodiment shown in FIG. 2, the temperature management system 10 can execute a heating operation in which, for example, a passenger cabin and / or a battery 500 (see, for example, a heating operation. FIGS. 4 to 7 ) of the vehicle are heated, as well as a cooling mode in which, for example, the passenger cabin and / or the battery 500 of the vehicle are cooled. The temperature management system 10 comprises a refrigerant circuit 200 for guiding the refrigerant, comprising a compressor 210 and a refrigerant delivery pump, not shown.A coolant circuit 100 for guiding a coolant is thermally coupled to the battery 500 of the vehicle, which in the present schematic view of FIG. 2 is combined in features 101 and feature 101' with further components of the coolant circuit 100, which components are not individually illustrated. The components 101 and 101' further comprise a coolant delivery pump and one or more valves 130, 140, 150, 160, 170, 180 (see FIGS. 4 and 5 ) for conducting the coolant as required. Reference numeral 105 designates a line system in which the coolant is conveyed between the individual components of the cooling circuit 100. Similarly, reference numeral 205 designates a corresponding conduit system of the refrigerant circuit 200 in which the refrigerant is conveyed.A first heat exchanger 300, in the embodiment shown a liquid cooled condenser (LCC), is thermally coupled to both the refrigerant circuit 200 and the coolant circuit 100. This means that heat can be transferred between the refrigerant circuit 200 and the coolant circuit 100.A second heat exchanger 400, in the embodiment shown a battery cooler, is thermally coupled to both the refrigerant circuit 200 and the coolant circuit 100 and is arranged behind the first heat exchanger 300 and in front of the compressor 210 with respect to a flow direction of the refrigerant in a heating operation.An electronic control unit, not shown, is connected in terms of control technology to the coolant delivery pump, the refrigerant delivery pump, the valves of the coolant circuit 100, and the valves of the refrigerant circuit 200, likewise shown in FIG. 2.The heat sources used for the heat pump can be a vehicle environment or also waste heat from the electric drive train of the vehicle. To use the waste heat of the electric drive train, for example from eAxle 112 and battery 500, which are combined in components 101 and 101', second heat exchanger 300, i.e. the battery cooler in the present case, is used.To use the heat from the environment, an ambient heat exchanger in the refrigerant circuit 200 or a heat exchanger for the coolant circuit 100 is required, which in turn is itself connected to an ambient heat exchanger 110. The latter can be, for example, a radiator, which usually serves for the heat dissipation of the electric drive train to the environment. An ambient heat exchanger 110 is combined in components 101 and 101' in FIG. 2 and is shown as part of the coolant circuit 100 in FIGS. 4 and 5.In order to be able to completely save an ambient heat exchanger in the refrigerant circuit 200 in the case of cabin cooling, not only the heat absorption but also the heat emission of refrigerant into coolant with subsequent transfer to the environment must be possible.For this purpose, in the embodiment of FIG. 2, the first heat exchanger 300 is used in the form of the liquid-cooled condenser, which has a fluid path to the ambient heat exchanger 110 (see FIGS. 4 and 5 ). The first heat exchanger 300 is disposed rearward of the electric compressor 210 with respect to a flow direction of the refrigerant so as to release the heat to the refrigerant at a higher temperature level. In the coolant circuit 200, it can be arranged both before and after the drive unit depending on the preference and design.Further components of the refrigerant circuit of the embodiment shown in FIG. 2 comprise an accumulator 270 which serves as an intermediate tank for the refrigerant, an electronically controlled expansion valve 220 for expanding the refrigerant after a condenser 240 used for heating the passenger cabin in the heating mode, and an evaporator 230 which is arranged behind the first heat exchanger 300 in a passenger cabin cooling mode of the heat pump.A shut-off valve 260 and two electronically controllable three-way valves 250, 251 serve to conduct the refrigerant as required to the evaporator 230, the condenser 240 and / or to the first heat exchanger 300.The first heat exchanger 300 may be used to introduce heat into the coolant circuit 100 via the heat pump functionality and thereby heat the battery, for example for preconditioning for DC charging at a quick-action air column or for power and life reasons at cold battery cell temperature. If the heat is to be discharged from the refrigerant circuit 200 via the first heat exchanger 300, the path to the condenser 240 is blocked via the 3-way valve 251.The problem has already been pointed out at the beginning that the heat pump can normally only be operated up to the temperature range at which the evaporation point of the refrigerant used can just be adjusted (e.g. -5 to -10° C.).In order to increase the efficiency of the heat pump functionality and to bypass the problem of limitation by the evaporation point of the refrigerant, the output heating power of the compressor is first returned to its inlet in order to increase the temperature level, according to the invention, before it is then discharged to the desired heat sink with sufficient heating power.This is done by a triangular process on the coolant side, which is explained in more detail below with reference to FIGS. 3 to 5. The coolant triangular process can be implemented in this case without additional valves being necessary on the refrigerant side.FIG. 3 ashows a schematic representation of the coolant circuit 100 and the refrigerant circuit 200 in heating operation, i.e. for fulfilling a heating requirement, for example for heating the passenger cabin of the vehicle. The reference numerals correspond to the reference numerals used in FIG. 2.Similar to the reference numerals 101, 101' of the coolant circuit 100, the reference numerals 201, 201' and 201" in FIG. 3 arepresent some or all of the components of the refrigerant circuit 200, which components are not illustrated in relation to FIG. 2, depending on the embodiment.As in FIG. 2, it can also be seen in FIG. 3 a that heat can be transferred between the refrigerant circuit 200 and the coolant circuit 100 at the first heat exchanger 300 and the second heat exchanger 400. In order to increase the heating power downstream of the compressor 210, according to the invention, a continuous increase in the temperature level takes place in the circuit, which extends in this case via the coolant circuit 100.The connection of the first 300 and second 400 heat exchangers in the common coolant pump driven coolant circuit 100 allows the first heat exchanger 300 to receive heat from the refrigerant circuit 200 after the compressor 210 and the second heat exchanger 400 to re-transfer heat to the refrigerant circuit 200 before entering the compressor 210. This is a triangular process with the return of the heating power, which is represented in FIG. 5 by the arrows 500, at the outlet of the compressor 210 via a bypass via the coolant circuit 100 back to the inlet of the compressor 210, in order thereby to promote a more rapid heating behavior.It is possible to carry out the triangular coolant process with further heat sources in the same coolant circuit 100, such as e.g. with the ambient heat exchanger 110 and a bypass valve for possible use of additional ambient heat, as well as the possible incorporation of the waste heat of the drive unit or other coolant-cooled components.FIG. 3 b, which uses the same reference numerals as FIG. 3 a, shows an exemplary implementation of the principle described with reference to FIG. 3 a. The coolant circuit 100 is depicted on the right-hand side in FIG. 3 b, and the refrigerant circuit 200 on the left-hand side. In contrast to FIG. 3 a, in FIG. 3 b, in heating operation, a flow direction runs on the coolant side from the second heat exchanger 400 to the first heat exchanger. The first 300 and the second heat exchanger 400 are incorporated into the two circuits for exchanging heat between the coolant circuit 100 and the refrigerant circuit 200. In addition, the coolant circuit 100 has a first heat sink 106, for example the vehicle battery 500 or a condenser used for heating the passenger cabin in heating operation.Furthermore, a plurality of heat sources are potentially incorporated into the coolant circuit 100 at the points identified by 108, 108' and 108", for example in the form of an ambient heat exchanger or as waste heat from a vehicle drive (eAxle 112). As shown in FIG. 3b, one heat source 108 may be located between the second heat exchanger 400 and the first heat exchanger, another heat source 108' may be located behind the first heat exchanger, and a third heat source 108" directly in front of the second heat exchanger 400.In order to now assist a more rapid heating on the coolant side, the coolant circuit 100 in the embodiment shown has a three-way valve 107 with one inlet and two outlets, which is arranged behind the first heat exchanger 300 and in front of the heat sink 106 with respect to the flow direction of the coolant. A first output of the three-way valve 107 is connected to the heat sink 106, while a second output short-circuits the refrigeration circuit 100 if necessary, such that the heat sink 106 is bypassed ("bypass"). The short-circuiting or, in other words, the integration or bypassing of the heat sink 106 as required allows no heat to be emitted to the heat sink 106 on the coolant side during the heating phase or, when only a part of the coolant is conducted through to the heat sink 106, only an acceptable amount of heat to be emitted to the heat sink 106, while a sufficiently large amount of heat is available for the triangular coolant process.In a similar manner, a three-way valve 207 is arranged in the refrigerant circuit 200 such that it can fully or partially bridge a heat sink 206 incorporated in the refrigerant circuit 200 as required. Here, the three-way valve 206 is disposed behind the compressor 210 and in front of the first heat exchanger 300 with respect to the flow direction of the refrigerant. By appropriate actuation of the three-way valve 207, the refrigerant flow can be conducted from the compressor 210 to the first heat exchanger 300 and further to the second heat exchanger 400 with exclusion of the heat sink 206, or from the compressor 210 via the heat sink 206 further to the second heat exchanger 400. In order to support rapid heating of the refrigerant circuit, the heat sink 206 can thus be completely or partially bypassed as required.In general, it should be noted that the three-way valve shown in FIG. 3 bis only one possible exemplary embodiment. In general, a valve device can be used which makes it possible to perform a distribution of the mass flow wholly or partly, so that a distribution of the available heat output to the desired heat sinks is made possible and a corresponding regulation is possible. For example, a proportional controllable 4-way valve for splitting the mass flow or the functionality of a 3-way valve can also be realized by two 2-way valves.FIGS. 4 and 5 show two alternative embodiments of the coolant circuit 100, as can be used to use the coolant triangular process just described.In the embodiment shown in FIG. 4, the coolant circuit 100 comprises a four-way valve 130, which can be regulated by the controller as required and has two inputs 131, 132 and two outputs 133, 134.Here, a first inlet 131 is fluidically connected to the first heat exchanger 300 and a first outlet 133 is connected to the second heat exchanger 400. A second inlet 132 receives a flow of coolant from the direction of thermal coupling to the battery 500. The second heat exchanger 400 is arranged fluidically between the four-way valve 130 and a first three-way valve 140, wherein the first three-way valve 140 conducts a coolant flow as required in the direction of the thermal coupling to the battery 500 and / or in the direction of the first heat exchanger 300. A second three-way valve 150 is arranged fluidically between the first three-way valve 140 and the first heat exchanger 300, wherein the second three-way valve 150 directs a coolant flow coming from the first three-way valve 140 directly to the first heat exchanger 300 as required and / or directs it via the ambient heat exchanger 110 to the first heat exchanger 300 while absorbing heat from the environment. In this case, the second three-way valve 150 is controlled at least partially as a function of an external temperature of the vehicle, which can be determined, for example, by means of an external temperature sensor.A second outlet of the four-way valve 130 is fluidically connected to a third three-way valve 160, wherein the third three-way valve 160 conducts a coolant flow coming from the four-way valve 130 as required in the direction of the thermal coupling to the battery 500 and / or in the direction of the second three-way valve 150.In the embodiment shown in FIG. 4, the first four-way valve 130, the first three-way valve 140, the second three-way valve 150, and the third three-way valve 160 are electronically controlled by the controller of the temperature management system 10.To increase the heating power, an electric heating element on the first heat exchanger 300 may be thermally coupled to the coolant circuit 100, or the electric heating element 120 may be thermally coupled to the coolant circuit 100 between the four-way valve 130 and the third three-way valve 160 as shown in FIG. 4.Depending on the way in which this approach is considered, advantages can be seen in a relative cost saving or an increased functionality, with which, for example, the response time in the request for cabin heating can be improved. The process facilitates independence of the heat pump operation from the evaporation point of the refrigerant and thus also contributes to the energy efficiency of the vehicle, since the operation of a heat pump is usually more energy efficient than the operation of electric heating elements. An increased energy efficiency thus contributes to maximizing the driving range.Alternatively or additionally, it would also be conceivable for the refrigerant delta process to be used simultaneously with a refrigerant delta process in which, on the side of the refrigerant circuit 200, refrigerant is conveyed directly from the outlet of the compressor 210 back to the compressor inlet by means of a corresponding arrangement of additional valves, in order to raise the temperature level as a result of this short circuit.The combination of the refrigerant delta process and the coolant delta process can thus result in an even further improved heating power. Due to the improved availability of the heat pump at cryogenic temperatures and an increased heating power, further electrical PTC heaters can likewise be saved with suitable dimensioning of the compressor.FIG. 5 shows a portion of another embodiment of the temperature management system 10, wherein instead of the four-way valve and the three-way valves 140, 150, 160, a five-way valve 170 and a four-way valve 180 are used. The four-way valve 170 and the five-way valve 180 are electronically controlled by the controller of the temperature management system 10.As can be seen in FIG. 5, the first heat exchanger 300 is arranged fluidically between a first outlet 173 of the five-way valve 170 and a first inlet 181 of the four-way valve 180. The second heat exchanger 400 is arranged fluidically between a first outlet 183 of the four-way valve 180 and a first inlet 171 of the five-way valve 170. The thermal coupling to the battery 500 is fluidly disposed between a second outlet 174 of the five-way valve 170 and a second inlet 182 of the four-way valve 180.A third output of the five-way valve 170 is fluidly connected to the ambient heat exchanger 120, which is disposed between the five-way valve 180 and the first heat exchanger 300. The coolant circuit 100 may be thermally coupled to an electric heating element 120 between a second outlet 184 of the four-way valve 180 and a second inlet 172 of the five-way valve 170, as shown in FIG. 5. Alternatively, an electric heating element on the first heat exchanger 300 may be thermally coupled to the coolant circuit 100.A temperature management method according to the invention comprises the following steps in both embodiments shown in FIGS. 4 and 5 :S1. compressing the refrigerant in the compressor 210 to raise a temperature level of the refrigerant;S 2 conveys the refrigerant in the refrigerant circuit 200 from the compressor 210 back to the compressor 210 via at least the first heat exchanger 300 and the second heat exchanger 400;S 3 conveys the coolant at least from the first heat exchanger 300 to the second heat exchanger 400 and back to the first heat exchanger 300;S 4. wherein, in the heating operation, heat from the refrigerant is transferred to the coolant at the first heat exchanger 300 and heat from the coolant is transferred to the refrigerant at the second heat exchanger 400.As already mentioned above, the arabic numerals in the designation of the method steps "S 1" to "S 4" serve merely for identifying the individual steps; this is not intended to define an order of the method steps. It is thus possible for step S 3 to be carried out before step S 1, for example. In particular, some or more of steps S 1 to S 4 can also be carried out in parallel or repeatedly in a loop.The heat present in the coolant is transferred to the refrigerant via the second heat exchanger 400 and is not, or not completely, emitted to another heat sink, for example the battery 500. The coolant temperature at the outlet of the second heat exchanger 400 decreases in the direction of the temperature level of the refrigerant, taking into account the thermal resistance. If the evaporation point of the refrigerant and thus the lowered coolant temperature is below the ambient temperature, the coolant can be diverted via the second three-way valve 150 to the ambient heat exchanger 110 in order to remove additional ambient heat via it. If the environment is too cold, the ambient heat exchanger 110 may also be bypassed via the second three-way valve 150. The heat output increased via the compressor 210 is introduced into the coolant via the first heat exchanger 300 and is thereby not or not completely discharged to another heat sink, for example the condenser 240, to the passenger cabin. This cycle may be continued until a temperature of the refrigerant at an outlet of the compressor 210 reaches a predetermined value that allows the heating power to be output to the desired heat sink.As an alternative to the disclosed topologies, further topology characteristics and interconnections can also exist, which likewise enable the coolant triangle process described above. Embodiments of the invention comprise, for example, topologies of the coolant circuit in which instead of the solutions shown in FIGS. 4 and 5, i.e. instead of a four-way valve and three three-way valves or a five-way valve and a four-way valve, two four-way valves and one three-way valve are used (in this regard, see the embodiment described further below with reference to FIG. 6 ), or three three-way valves and one four-way valve. Also, in some embodiments, it is contemplated to use five three-way valves in the coolant circuit. It should generally be noted that the use of more highly integrated multiway valves and various combinations of valves is possible.To further increase the heating potential, the waste heat of the drive unit of the vehicle can likewise be incorporated, wherein the incorporation can be arranged before or after the first heat exchanger 300 depending on the preference and design. This is particularly useful when a targeted waste heat production can be set (also: "waste heat generation") via a deliberate inefficient operation of the eAx (in the summary as inverter, eMachine and transmission). In addition to the drive unit, depending on the availability of other heat sources, these can likewise be incorporated into the thermal topology, so that they promote the coolant delta process.With reference to FIGS. 6 and 7, further implementations of a temperature management system 10 according to the invention and of a method for temperature management are now presented. The reference numerals used in FIG. 2 are used for identical features.In the temperature management system 10 shown in FIG. 6, the above-described refrigerant delta process can be operated in conjunction with a heat pump for heating the passenger cabin. For heating the passenger cabin, the condenser 240 is arranged for this purpose, as is also the case in the system shown in FIG. 2. In contrast to the embodiment shown in FIG. 2, the condenser 240 is not incorporated into the refrigerant circuit 200 via a three-way valve in the embodiment of FIG. 6, but rather via an electronically controlled expansion valve 261 which is arranged behind the compressor 210 in the flow direction of the refrigerant in the heating operation. In the fluidic connection between the compressor 210 and the first heat exchanger 300, which may be a liquid-cooled condenser, a further electronically controlled expansion valve 252 is arranged, via which refrigerant can be conducted to the first heat exchanger 300. A further electronically controlled expansion valve 262 connects the evaporator 230 in the cooling mode, and an electronically controlled expansion valve 263 is arranged upstream of the second heat exchanger in the flow direction.The second heat exchanger 400, which may be a battery cooler, is arranged in front of the compressor 210 and in front of the accumulator 270 respectively with respect to the flow direction of the refrigerant in the heating operation as already described in FIG. 2.Taking into account the valve arrangement configured differently in comparison with the embodiment of FIG. 2, the refrigerant flow in the temperature management system of FIG. 6 can be circulated as required in the refrigerant circuit 200 by bypassing the condenser 240 in order to promote rapid heating thereof. If necessary, the arrangement of the expansion valves 252, 261 makes it possible to conduct a part of the heating power or also the complete one to the capacitor 240.With regard to the coolant circuit 100, FIG. 6 shows a construction which is similar to the coolant circuit 100 described in FIG. 4, but has a first 1700 and a second proportionally controllable four-way valve 1800 and a three-way valve 118 instead of a four-way valve 130 and three three-way valves 140, 150, 160. In addition, FIG. 6 explicitly shows further components of the coolant circuit 100, for example the ambient heat exchanger 110 and a three-way valve 118, by means of which the ambient heat exchanger can be incorporated or bridged into the coolant circuit 100 as required. In addition, FIG. 6 shows the incorporation of waste heat from the e-axis 112 in front of the first heat exchanger 300 and the position of two coolant pumps 115, 115' in front of the battery 500 and in front of the three-way valve 118.As can be seen from FIG. 6, the battery 500 is arranged between the first 1700 and the second four-way valve 1800, such that the coolant flow coming from the first heat exchanger 300 can be conducted via the second four-way valve 1800 to the second heat exchanger 400, via an optionally arranged heating element 120, or optionally partially or completely via a sub-circuit 100' which encloses the battery 500. In this way, the coolant temperature at the battery 500 may be adjusted as needed. To assist in rapidly heating the coolant circuit 100, the battery 500 may be bypassed and the coolant delta process assists in rapidly heating the coolant circuit 100 as well as the refrigerant circuit 200.In contrast to FIG. 6, FIG. 7 shows a temperature management system 10, in which although the above-described refrigerant delta process is used in connection, heating of the passenger cabin is not effected via a heat pump operation with condenser 240 but rather by a cabin heat exchanger 111 in the refrigerant circuit 100.In the embodiment shown, the refrigerant circuit 200 comprises only the components compressor 210, first heat exchanger 300, second heat exchanger 400, and evaporator 230, which are connected to corresponding lines 205. A three-way valve 255, which is arranged behind the first heat exchanger 300, makes it possible to direct the refrigerant flow, if necessary, fully or partially via the evaporator and / or via the second heat exchanger 400 to the compressor 210, from which the refrigerant reaches the first heat exchanger 300 again. Alternatively, in embodiments of the invention, two electronic expansion valves are arranged instead of the three-way valve 255.The coolant circuit 100 is in principle similar to the coolant circuit 100 shown in FIG. 6, but comprises a four-way valve 1900, a five-way valve 2000, and two three-way valves 118, 119 for conducting the coolant as required, wherein the second three-way valve 199 is optional. The ambient heat exchanger 110 is incorporated or bridged as required via the first three-way valve 118. The second three-way valve 119 selectively directs the coolant coming from the first three-way valve 118 to the four-way valve 1900 and from there to the first heat exchanger 300, or at least partially bridges the first heat exchanger 300 and directs the coolant flow to the cabin heat exchanger 111 and the five-way valve 2000.Starting from the five-way valve 2000, the coolant can be selectively conducted back to the first three-way valve 118, or to a sub-circuit 100', which starting from the five-way valve 2000 comprises the components of second heat exchangers 400, four-way valve 1900 and battery 500 in succession. Optionally, an electric heating element 120 can also be provided behind the five-way valve 2000.The invention is not limited to the exemplary embodiments described and illustrated. Rather, it also includes all technical developments within the scope of the invention defined by the patent claims.In addition to the described and depicted embodiments, further embodiments are conceivable which can comprise further modifications and combinations of features.

Claims

Method for temperature management in a vehicle, in particular a battery-electrically driven vehicle, the vehicle comprising a coolant circuit (100) for transporting coolant, wherein the coolant circuit (100) is thermally coupled at least to a first heat exchanger (300) and a second heat exchanger (400), a refrigerant circuit (200) for transporting refrigerant, wherein the refrigerant circuit (200) is thermally coupled at least to the first heat exchanger (300) and the second heat exchanger (400) and has a compressor (210) for compressing the refrigerant, the method comprising the steps: S1. compressing the refrigerant in the compressor (210) while raising a temperature level of the refrigerant; S2. conveying the refrigerant in the refrigerant circuit (200) from the compressor (210) via at least the first heat exchanger (300) and the second heat exchanger (400) back to the compressor (210); S 3 conveys the coolant at least from the first heat exchanger (300) to the second heat exchanger (400) and back to the first heat exchanger (300); S 4. wherein, in a heating operation, heat from the refrigerant is transferred to the coolant at the first heat exchanger (300) and heat from the coolant is transferred to the refrigerant at the second heat exchanger (400).Method according to Claim 1, characterized in that, in step S3, heat is emitted as required and / or partially from the coolant to one or more further heat sinks which are thermally coupled to the coolant circuit (200), for example to a vehicle battery (500) or to a passenger cabin.Method according to one of Claims 1 and 2, characterized in that, in step S3, heat is taken from a vehicle environment using an ambient heat exchanger (110) and is emitted to the coolant.Method according to one of Claims 1 to 3, characterized in that, in step S3, heat is generated with an electrical heating element (120) and is emitted to the coolant.Method according to one of Claims 1 to 4, characterized in that, in step S3, heat from waste heat from a drive unit of the vehicle is emitted to the coolant.Method according to one of Claims 1 to 5, characterized in that, in step S2, heat is emitted, if required and / or partially, from the refrigerant to one or more further heat sinks which are thermally coupled to the refrigerant circuit (200), for example to a condenser (240) for heating an operator's compartment of the vehicle or for heating a refrigerant-cooled battery.Method according to one of Claims 1 to 6, characterized in that in step S2 heat from one or more heat sources is emitted to the refrigerant, for example ambient heat, waste heat from the compressor, or from additional electrical heating elements.Method according to one of Claims 1 to 7, characterized in that the steps S1 to S4 are carried out until a temperature of the refrigerant at an outlet of the compressor (210) reaches a predetermined value.Temperature management system (10) for a vehicle, in particular a battery-electrically driven vehicle, comprising: - a refrigerant circuit (200) for guiding a refrigerant, comprising at least one compressor (210) and a refrigerant delivery pump; - a coolant circuit (100) for guiding a coolant, wherein the coolant circuit (100) is thermally coupled to a battery (500) of the vehicle and comprises at least one coolant delivery pump, the coolant circuit (100) having one or more valves (130, 140, 150, 160, 170, 180) for conducting the coolant as required; - a first heat exchanger (300), in particular a liquid-cooled condenser (LCC), which is thermally coupled both to the refrigerant circuit (200) and to the coolant circuit (100); a second heat exchanger (400), in particular a battery cooler, which is thermally coupled both to the refrigerant circuit (200) and to the coolant circuit (100) and is arranged behind the first heat exchanger (300) and in front of the compressor (210) with respect to a flow direction of the refrigerant in a heating operation; a controller, which is connected in terms of control technology to the coolant delivery pump, the refrigerant delivery pump, and the one or more valves (130, 140, 150, 160, 170, 180) of the coolant circuit (100) and is configured to carry out the method according to one of claims 1 to 8.Temperature management system (10) according to claim 9, characterised in that the coolant circuit (100) is thermally coupled to an ambient heat exchanger (110), via which heat is taken from a vehicle environment and supplied to the coolant.The temperature management system (10) according to any one of claims 9 and 10, characterized in that the refrigerant circuit (200) is thermally coupled to a condenser (240) for heating an operator's cabin of the vehicle, the condenser (240) being disposed behind the compressor (210) with respect to a flow direction of the refrigerant.Temperature management system (10) according to claims 9 to 11, characterised in that the coolant circuit (100) comprises a four-way valve (130), which can be controlled by the controller as required and has two inputs (131, 132) and two outputs (133, 134), wherein: - a first input (131) is fluidically connected to the first heat exchanger (300) and a first output (133) is connected to the second heat exchanger (400); - a second input (132) receives a coolant flow from the direction of thermal coupling to the battery (500).Temperature management system (10) according to claim 12, characterised in that the second heat exchanger (400) is arranged fluidically between the four-way valve (130) and a first three-way valve (140), wherein the first three-way valve (140) directs a coolant flow as required in the direction of the thermal coupling to the battery (500) and / or in the direction of the first heat exchanger (300).Temperature management system (10) according to claim 13, characterised in that a second three-way valve (150) is arranged fluidically between the first three-way valve (140) and the first heat exchanger (300), wherein the second three-way valve (150) directs a coolant flow coming from the first three-way valve (140) directly to the first heat exchanger (300) as required and / or directs it via the ambient heat exchanger (110) to the first heat exchanger (300).Temperature management system (10) according to one of Claims 12 to 14, characterized in that a second outlet (134) of the four-way valve (130) is fluidically connected to a third three-way valve (160), wherein the third three-way valve (160) conducts a coolant stream coming from the four-way valve (130) as required in the direction of thermal coupling to the battery (500) and / or in the direction of the second three-way valve (150).The thermal management system (10) of claim 15, characterized in that the coolant circuit (100) is thermally coupled to an electrical heating element (120) between the four-way valve (130) and the third three-way valve (160).Temperature management system (10) according to one of claims 9 to 16, characterized in that an electric heating element at the first heat exchanger (300) is thermally coupled to the coolant circuit (100).Temperature management system (10) according to any of claims 9 to 11, characterized in that the coolant circuit (100) comprises a five-way valve (170) and a four-way valve (180), wherein: - the first heat exchanger (300) is fluidically arranged between a first outlet (173) of the five-way valve (170) and a first inlet (181) of the four-way valve (180); - the second heat exchanger (400) is fluidically arranged between a first outlet (183) of the four-way valve (180) and a first inlet (171) of the five-way valve (170); and the thermal coupling to the battery (500) is arranged fluidically between a second outlet (174) of the five-way valve (170) and a second inlet (182) of the four-way valve (180).Temperature management system (10) according to claim 18, characterized in that a third outlet (175) of the five-way valve (170) is fluidically connected to an ambient heat exchanger (110), which is arranged between the five-way valve (170) and the first heat exchanger (300).The thermal management system (10) of any of claims 18 and 19, characterized in that the coolant circuit (200) is thermally coupled to an electrical heating element (120) between a second outlet (184) of the four-way valve (180) and a second inlet (172) of the five-way valve (170).Temperature management system (10) according to one of claims 18 to 20, characterised in that an electrical heating element at the first heat exchanger (300) is thermally coupled to the coolant circuit (100).

Images