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-powered electric vehicle, the vehicle comprising a coolant circuit (100) for transporting coolant, the coolant circuit being thermally coupled at least to a first heat exchanger (300) and a second heat exchanger (400); and a refrigerant circuit (200) for transporting refrigerant, the refrigerant circuit being thermally coupled at least to the first heat exchanger and to the second heat exchanger and having a compressor (210) for compressing the refrigerant, wherein, in a heating mode, 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). The invention also relates to a temperature management system for a vehicle, in particular a battery-powered electric vehicle, comprising a thermally coupled battery (500).

Description

[0001] Description

[0002] title

[0003] Method and system for temperature management in a vehicle

[0004] The invention relates to a method for temperature management in a vehicle and a temperature management system for a vehicle. The vehicle is, in particular, a battery-electric vehicle.

[0005] State of the art

[0006] The energy management of battery-electric vehicles (BEVs) is essential for the efficient use of available electrical energy in order to maximize the driving range while simultaneously meeting the requirements for component service life and passenger comfort.

[0007] In this context, the coordinated thermal management of the powertrain, together with the temperature conditioning of the passenger cabin, plays a key role in optimizing this goal within the overall system. One requirement here may be that the passenger cabin must be heated at low outside temperatures to ensure the thermal comfort of the passengers. If a heat pump is installed in the vehicle to increase efficiency, this can extract heat from a heat source via a refrigerant circuit via an evaporator located upstream of a compressor and transfer it to a heat sink via a condenser located downstream of the compressor.

[0008] Before heat is released, the evaporated refrigerant is brought to a higher temperature by increasing the pressure via the compressor to achieve greater heat release. The pressure is then released back to its original level.

[0009] The disadvantage of heat pumps is that their efficiency drops significantly with colder outside temperatures, and the required electrical power therefore increases with the difference from the target temperature. Furthermore, heat pumps can typically only be operated up to the temperature range where the evaporation point of the refrigerant used can still be adjusted (e.g., -5 to -10°C).

[0010] Therefore, for extremely low temperatures, additional electrical heating elements (“positive temperature coefficient” or PTC heaters) are often installed in the state of the art in order to be able to heat the air in the passenger cabin.

[0011] For reasons such as the energy efficiency of the temperature management system as well as the additional costs and loss of available design space in the vehicle, the sole use of electrical heating elements is considered problematic.

[0012] It is an object of the invention to provide an alternative or improved method for temperature management in a vehicle, in particular a battery-electric vehicle, as well as a temperature management system for a vehicle, in particular a battery-electric vehicle.

[0013] Disclosure of the invention

[0014] The object of the invention is achieved by means of a method according to claim 1, as well as by a temperature management system according to claim 8. Advantageous developments, additional features and / or advantages of the invention emerge from the dependent claims and the following description.

[0015] According to a first aspect, the present disclosure discloses 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:

[0016] 51. compressing the refrigerant in the compressor while raising a temperature level of the refrigerant;

[0017] 52. 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;

[0018] 53. conveying the coolant at least from the first heat exchanger to the second heat exchanger and back to the first heat exchanger;

[0019] 54. wherein, in a heating operation, heat is transferred from the refrigerant to the cooling medium at the first heat exchanger and heat is transferred from the cooling medium to the refrigerant at the second heat exchanger.

[0020] Within the scope of the invention, the Arabic numerals in the designation of the method steps "S1" to "S4" serve merely to identify the individual steps; they are not intended to specify a sequence of the method steps. For example, it is possible for step S3 to be executed before step S1. In particular, some or more of steps S1 to S4 can also be executed in parallel or repeatedly in a loop.

[0021] In step S3, heat from the coolant can be transferred, as needed and / or partially, to one or more additional heat sinks that are thermally coupled to the coolant circuit, for example, to a vehicle battery or a passenger cabin. In step S3, heat can be extracted from the vehicle's surroundings using an ambient heat exchanger and transferred to the coolant.

[0022] In step S3, heat can be generated using an electrical heating element and transferred to the coolant.

[0023] In step S3, heat from waste heat of a drive unit of the vehicle can be transferred to the coolant.

[0024] In step S2, heat from the refrigerant can be transferred, as needed and / or partially, to one or more additional heat sinks that are thermally coupled to the refrigerant circuit, for example, to a condenser for heating a driver's cab of the vehicle or for heating a refrigerant-cooled battery. In step S2, heat from one or more heat sources can be transferred to the refrigerant, for example, ambient heat, waste heat from the compressor, or from additional electrical heating elements.

[0025] Steps S1 to S4 can be performed until a temperature of the refrigerant at an outlet of the compressor reaches a predetermined value.

[0026] According to a second aspect, the present disclosure discloses a temperature management system for a vehicle, in particular a battery-electric vehicle, comprising: a refrigerant circuit for conducting a refrigerant, comprising at least one compressor and a refrigerant feed pump; a coolant circuit for conducting a coolant, wherein the coolant circuit is thermally coupled to a battery of the vehicle and comprises at least one coolant feed pump, the coolant circuit having one or more valves for conducting the coolant as needed; a first heat exchanger, in particular a liquid-cooled condenser (LCC), which is thermally coupled to both the refrigerant circuit and the coolant circuit;a second heat exchanger, in particular a battery cooler, which is thermally coupled to both the refrigerant circuit and the coolant circuit and, with respect to a flow direction of the refrigerant in a heating mode, is arranged downstream of the first heat exchanger and upstream of the compressor; a controller which is control-technically connected to the coolant feed pump, the refrigerant feed pump, and the one or more valves of the coolant circuit and is configured to carry out the method according to claim 1;

[0027] The coolant circuit can be thermally coupled to an ambient heat exchanger, through which heat is extracted from the vehicle environment and supplied to the coolant.

[0028] The refrigerant circuit can be thermally coupled to a condenser for heating a driver's cab of the vehicle, wherein the condenser is arranged behind the compressor with respect to a flow direction of the refrigerant.

[0029] The coolant circuit may comprise a four-way valve, which can be controlled by the controller as needed and has two inlets and two outlets, wherein: a first inlet is fluidically connected to the first heat exchanger and a first outlet to the second heat exchanger; a second inlet receives a coolant flow from the direction of the thermal coupling with the battery. The second heat exchanger may be fluidically arranged between the four-way valve and a first three-way valve, wherein the first three-way valve directs a coolant flow as needed toward the thermal coupling with the battery and / or toward the first heat exchanger.

[0030] A second three-way valve can be fluidically arranged 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 needed and / or via the ambient heat exchanger to the first heat exchanger.

[0031] A second output 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 with the battery and / or in the direction of the second three-way valve.

[0032] The coolant circuit can be thermally coupled to an electric heating element between the four-way valve and the third three-way valve. An electric heating element can be thermally coupled to the coolant circuit at the first heat exchanger.

[0033] The coolant circuit may comprise a five-way valve and a four-way valve, wherein: the first heat exchanger is fluidically arranged between a first output of the five-way valve and a first input of the four-way valve; the second heat exchanger is fluidically arranged between a first output of the four-way valve and a first input of the five-way valve; and the 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.

[0034] A third output of the five-way valve may be fluidly connected to an ambient heat exchanger arranged between the five-way valve and the first heat exchanger.

[0035] The coolant circuit may be thermally coupled to an electric heating element between a second output of the four-way valve and a second input of the five-way valve.

[0036] An electrical heating element can be thermally coupled to the coolant circuit at the first heat exchanger.

[0037] Short description of the characters

[0038] The invention is explained in more detail below using exemplary embodiments with reference to the attached schematic and not-to-scale drawing. In the invention, a feature can be configured positively, i.e., present, or negatively, i.e., absent. In this specification, a negative feature is not explicitly explained as a feature unless it is important for the invention to be absent. This means that the invention actually made, and not one constructed by the prior art, consists in omitting this feature. The absence of a feature (negative feature) in an exemplary embodiment indicates that the feature is optional. - In the merely exemplary figures (Fig.) of the drawing:

[0039] Fig. 1 schematically shows the structure and 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;

[0040] Fig. 3a shows schematically the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention;

[0041] Fig. 3b shows schematically the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention;

[0042] Fig. 4 shows schematically the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention, on a coolant side;

[0043] Fig. 5 shows schematically the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention, on a coolant side;

[0044] Fig. 6 shows schematically the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention;

[0045] Fig. 7 shows schematically the structure and operation of a temperature management system for a vehicle according to an embodiment of the invention;

[0046] Description

[0047] Figure 1 schematically shows the structure and operation of a heat pump 1 according to the prior art. Refrigerant is pumped into a refrigerant circuit 7 by a refrigerant pump (not shown). The refrigerant comprises, in particular, propane (R290) and / or CO2 (R744). The heat pump 1 extracts heat from a heat source 5 via an evaporator 3 and transfers it to a heat sink 6 via a condenser 4. Before the heat is released at the condenser 4, the refrigerant evaporated at the evaporator 3 is first brought to a higher temperature level by increasing the pressure via an electric compressor 2 in order to achieve greater heat release. The pressure is then released back to the original level, typically by an electronically controlled expansion valve 8.

[0048] The structure and operation of a temperature management system 10 according to the invention for a vehicle, in which the heat pump principle is used, are explained schematically below with reference to Figure 2. In the embodiment shown in Figure 2, the temperature management system 10 can carry out both a heating operation, in which, for example, a passenger cabin and / or a battery 500 (see, for example, Figures 4 to 7) of the vehicle are heated, and a cooling operation, 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 conducting the refrigerant, having a compressor 210 and a refrigerant feed pump (not shown).

[0049] A coolant circuit 100 for conveying a coolant is thermally coupled to the vehicle's battery 500, which, in the present schematic view of Figure 2, is combined in features 101 and feature 10T with other components of the coolant circuit 100 not shown individually. Components 101 and 10T further comprise a coolant feed pump and one or more valves 130, 140, 150, 160, 170, 180 (see Figures 4 and 5) for conveying the coolant as needed. Reference numeral 105 denotes a line system in which the coolant is conveyed between the individual components of the cooling circuit 100. Similarly, reference numeral 205 denotes a corresponding line 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.

[0050] 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 upstream of the compressor 210 with respect to a flow direction of the refrigerant in a heating mode.

[0051] An electronic control unit (not shown) is connected for control purposes to the coolant feed pump, the refrigerant feed pump, the valves of the coolant circuit 100, and the valves of the refrigerant circuit 200, which are also shown in Figure 2.

[0052] The heat pump's heat sources can be the vehicle's surroundings or waste heat from the vehicle's electric drive train. To utilize the waste heat from the electric drive train, for example, from the e-axle 112 and battery 500, which are combined in components 101 and 10T, the second heat exchanger 300, in this case the battery cooler, is used.

[0053] To utilize the heat from the environment, an ambient heat exchanger is required in the refrigerant circuit 200 or a heat exchanger to the coolant circuit 100, which in turn is connected to an ambient heat exchanger 110. The latter can, for example, be a radiator, which is typically used to dissipate heat from the electric drive train to the environment. An ambient heat exchanger 110 is summarized in Figure 2 in components 101 and 10T and is shown in Figures 4 and 5 as part of the coolant circuit 100.

[0054] In order to completely eliminate the need for an ambient heat exchanger in the refrigerant circuit 200 in the case of cabin cooling, it must be possible not only to absorb heat but also to release heat from the refrigerant into the coolant with subsequent transfer to the environment.

[0055] In the embodiment of Figure 2, the first heat exchanger 300 serves this purpose in the form of a liquid-cooled condenser, which has a fluid path to the ambient heat exchanger 110 (see Figures 4 and 5). The first heat exchanger 300 is arranged downstream of the electric compressor 210 with respect to the direction of refrigerant flow, thus transferring heat to the coolant at a higher temperature level. Depending on preference and design, it can be arranged either upstream or downstream of the drive unit in the coolant circuit 200.

[0056] Further components of the refrigerant circuit of the embodiment shown in Figure 2 include an accumulator 270, which serves as an intermediate tank for the refrigerant, an electronically controlled expansion valve 220 for expanding the refrigerant downstream of a condenser 240 used for heating the passenger cabin in heating mode, and an evaporator 230, which is arranged downstream of the first heat exchanger 300 in a passenger cabin cooling mode of the heat pump.

[0057] A shut-off valve 260 and two electronically controlled three-way valves 250, 251 serve to direct the refrigerant to the evaporator 230, the condenser 240, and / or to the first heat exchanger 300 as required.

[0058] The first heat exchanger 300 can 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 direct current charging at a rapid charging station or for performance and service life reasons at cold battery cell temperatures. If the heat from the coolant circuit 200 is to be released via the first heat exchanger 300, the path to the condenser 240 is blocked via the 3-way valve 251.

[0059] The problem already mentioned at the beginning is 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 set (e.g. -5 to -10°C).

[0060] In order to increase the efficiency of the heat pump functionality and to avoid the problem of limitations caused by the evaporation point of the refrigerant, the output heating power of the compressor is initially returned to its inlet to increase the temperature level, before it is then released to the desired heat sink when the heating power is sufficient.

[0061] This is achieved through a triangular process on the coolant side, which is explained in more detail below with reference to Figures 3 to 5. The coolant triangular process can be implemented without the need for additional valves on the refrigerant side.

[0062] Figure 3a shows a schematic representation of the coolant circuit 100 and the refrigerant circuit 200 in heating mode, i.e., to meet a heating requirement, for example, to heat the passenger cabin of the vehicle. The reference numerals correspond to the reference numerals used in Figure 2.

[0063] Similar to the reference numerals 101, 10T of the coolant circuit 100, the reference numerals 201, 20T, and 201" in Figure 3a represent, depending on the embodiment, some or all of the components of the refrigerant circuit 200 not shown in Figure 2.

[0064] As in Figure 2, Figure 3a also shows 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. To increase the heating output downstream of the compressor 210, the temperature level in the circuit is continuously raised, extending across the coolant circuit 100.

[0065] The connection of the first heat exchanger 300 and the second heat exchanger 400 in the common coolant circuit 100 driven by the coolant pump allows the first heat exchanger 300 to absorb the heat from the refrigerant circuit 200 downstream of the compressor 210, and the second heat exchanger 400 to transfer the heat back to the refrigerant circuit 200 upstream of the inlet of the compressor 210. This is a triangular process with the return of the heating power, represented in Figure 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, thereby promoting faster heating.

[0066] It is possible to carry out the coolant triangulation process with additional heat sources in the same coolant circuit 100, such as with the ambient heat exchanger 110 and a bypass valve for the possible use of additional ambient heat, as well as the possible integration of the waste heat of the drive unit or other coolant-cooled components.

[0067] Figure 3b, which uses the same reference numerals as Figure 3a, shows an exemplary implementation of the principle described in relation to Figure 3a. The coolant circuit 100 is depicted on the right-hand side in Figure 3b, the refrigerant circuit 200 on the left-hand side. In contrast to Figure 3a, in Figure 3b, the flow direction on the coolant side runs from the second heat exchanger 400 to the first heat exchanger during heating operation. The first heat exchanger 300 and the second heat exchanger 400 are integrated into the two circuits for the exchange of 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 to heat the passenger cabin during heating operation.

[0068] Furthermore, potentially several heat sources are integrated into the coolant circuit 100 at the locations marked by 108, 108', and 108", for example in the form of an ambient heat exchanger or as waste heat from a vehicle drive (e-axis 112). As shown in Figure 3b, a heat source 108 can be arranged between the second heat exchanger 400 and the first heat exchanger, another heat source 108' can be arranged behind the first heat exchanger, and a third heat source 108" directly in front of the second heat exchanger 400. In order to support faster 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 when necessary, bypassing the heat sink 106. Short-circuiting, or in other words, incorporating or bypassing the heat sink 106 as needed, allows no heat to be released to the heat sink 106 on the coolant side during the heating phase, or, if only a portion of the coolant is passed through to the heat sink 106, only an acceptable amount of heat to be released, while a sufficiently large amount of heat is available for the coolant triangulation process.

[0069] Similarly, a three-way valve 207 is arranged in the refrigerant circuit 200 such that a heat sink 206 integrated in the refrigerant circuit 200 can be completely or partially bypassed as needed. The three-way valve 206 is arranged downstream of the compressor 210 and upstream of the first heat exchanger 300 with respect to the flow direction of the refrigerant. By appropriately controlling the three-way valve 207, the refrigerant flow can be directed from the compressor 210 to the first heat exchanger 300 and further to the second heat exchanger 400, excluding the heat sink 206, or from the compressor 210 via the heat sink 206 to the second heat exchanger 400. To support rapid heating of the refrigerant circuit, the heat sink 206 can thus be completely or partially bypassed as needed.

[0070] In general, it should be noted that the three-way valve shown in Figure 3b is only one possible embodiment. In general, a valve device can be used that allows the mass flow to be divided completely or partially, thus enabling the available heat output to be distributed among the desired heat sinks and enabling appropriate control. For example, a proportionally controllable 4-way valve can also be used to split the mass flow, or the functionality of a 3-way valve can be implemented using two 2-way valves.

[0071] Figures 4 and 5 show two alternative embodiments of the coolant circuit 100 as it can be used to utilize the coolant triangulation process just described.

[0072] In the embodiment shown in Figure 4, the coolant circuit 100 comprises a four-way valve 130, which can be controlled by the controller as required and has two inlets 131, 132 and two outlets 133, 134.

[0073] Here, a first inlet 131 is fluidly connected to the first heat exchanger 300, and a first outlet 133 is fluidly connected to the second heat exchanger 400. A second inlet 132 receives a coolant flow from the direction of the thermal coupling with the battery 500. The second heat exchanger 400 is fluidly arranged 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 needed in the direction of the thermal coupling with the battery 500 and / or in the direction of the first heat exchanger 300. A second three-way valve 150 is fluidically arranged 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 needed and / or via the ambient heat exchanger 110 to the first heat exchanger 300 while absorbing heat from the environment.The second three-way valve 150 is controlled at least partially as a function of an outside temperature of the vehicle, which can be determined, for example, via an outside temperature sensor.

[0074] A second output of the four-way valve 130 is fluidly connected to a third three-way valve 160, wherein the third three-way valve 160 directs a coolant flow coming from the four-way valve 130, as needed, toward the thermal coupling with the battery 500 and / or toward the second three-way valve 150. In the embodiment shown in Figure 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.

[0075] To increase the heating power, an electric heating element on the first heat exchanger 300 can be thermally coupled to the coolant circuit 100, or the electric heating element 120 can be thermally coupled to the coolant circuit 100 between the four-way valve 130 and the third three-way valve 160, as shown in Figure 4.

[0076] Depending on the perspective, the advantages of this approach can be seen in relative cost savings or increased functionality, which can, for example, improve the response time when requesting cabin heating. The process promotes the independence of heat pump operation from the refrigerant's evaporation point and thus also contributes to the vehicle's energy efficiency, since heat pump operation is typically more energy-efficient than the operation of electric heating elements. Increased energy efficiency thus contributes to maximizing driving range.

[0077] Alternatively or additionally, it would also be conceivable for the coolant triangulation process to be used simultaneously with a refrigerant triangulation process, in which, on the refrigerant circuit 200 side, refrigerant is conveyed from the outlet of the compressor 210 directly back to the compressor inlet by means of a corresponding arrangement of additional valves in order to raise the temperature level by means of this short circuit.

[0078] The combination of the refrigerant triangulation process and the coolant triangulation process can thus result in even further improved heating performance. Due to the improved availability of the heat pump at extremely low temperatures and the increased heating performance, additional electrical PTC heaters can also be eliminated with appropriate compressor dimensioning. Figure 5 shows part of another embodiment of the temperature management system 10, wherein a five-way valve 170 and a four-way valve 180 are used instead of the four-way valve and the three-way valves 140, 150, and 160. The four-way valve 170 and the five-way valve 180 are electronically controlled by the controller of the temperature management system 10.

[0079] As can be seen in Figure 5, 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. The thermal coupling with the battery 500 is fluidically arranged between a second outlet 174 of the five-way valve 170 and a second inlet 182 of the four-way valve 180.

[0080] A third output of the five-way valve 170 is fluidically connected to the ambient heat exchanger 120, which is arranged between the five-way valve 180 and the first heat exchanger 300. As shown in Figure 5, the coolant circuit 100 can be thermally coupled to an electrical heating element 120 between a second output 184 of the four-way valve 180 and a second input 172 of the five-way valve 170. Alternatively, an electrical heating element on the first heat exchanger 300 can be thermally coupled to the coolant circuit 100.

[0081] A temperature management method according to the invention comprises the following steps in both embodiments shown in Figures 4 and 5:

[0082] 51. Compressing the refrigerant in the compressor 210 while raising a temperature level of the refrigerant;

[0083] 52. 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; 53. conveying the coolant at least from the first heat exchanger 300 to the second heat exchanger 400 and back to the first heat exchanger 300;

[0084] 54. wherein, in heating operation, heat is transferred from the refrigerant to the coolant at the first heat exchanger 300 and heat is transferred from the coolant to the refrigerant at the second heat exchanger 400.

[0085] As already noted above, the Arabic numerals in the designation of the process steps "S1" to "S4" serve only to identify the individual steps; they are not intended to specify a sequence of the process steps. For example, it is possible for step S3 to be executed before step S1. In particular, some or more of steps S1 to S4 can also be executed in parallel or repeatedly in a loop.

[0086] The heat present in the coolant is transferred to the refrigerant via the second heat exchanger 400 and is not, or not completely, transferred to another heat sink, for example, the battery 500. The coolant temperature at the outlet of the second heat exchanger 400 drops toward the temperature level of the refrigerant, taking thermal resistance into account. If the evaporation point of the refrigerant and thus the reduced coolant temperature are below the ambient temperature, the coolant can be redirected to the ambient heat exchanger 110 via the second three-way valve 150 in order to extract additional ambient heat. If the ambient temperature is too cold, the ambient heat exchanger 110 can also be bypassed via the second three-way valve 150.The heat output increased by the compressor 210 is introduced into the coolant via the first heat exchanger 300 and is not, or not completely, delivered to another heat sink, for example the condenser 240, in the passenger cabin. This cycle can be continued until a temperature of the coolant at an outlet of the compressor 210 reaches a predetermined value that allows the heating power to be delivered to the desired heat sink. As an alternative to the topologies disclosed, other topology variants and interconnections can also exist, which also enable the coolant triangulation process described above. Embodiments of the invention include, for example, topologies of the coolant circuit in which, instead of the solutions shown in Figures 4 and 5, ieInstead of one four-way valve and three three-way valves, or one five-way valve and one four-way valve, two four-way valves and one three-way valve can be used (see the embodiment described below with reference to Figure 6), or three three-way valves and one four-way valve. Likewise, some embodiments provide for the use of five three-way valves in the coolant circuit. It should be noted in general that the use of more highly integrated multi-way valves and various combinations of valves is possible.

[0087] To further increase the heating potential, the waste heat from the vehicle's drive unit can also be integrated. Depending on preference and design, the integration can be arranged before or after the first heat exchanger 300. This is particularly useful when targeted waste heat production (also known as "waste heat generation") can be achieved through deliberately inefficient operation of the e-axle (collectively, the inverter, e-machine, and transmission). In addition to the drive unit, other heat sources can also be integrated into the thermal topology, depending on their availability, thus promoting the coolant triangulation process.

[0088] Further implementations of a temperature management system 10 according to the invention and a method for temperature management are now presented with reference to Figures 6 and 7. The reference numerals used in Figure 2 are used for identical features.

[0089] In the temperature management system 10 shown in Figure 6, the coolant triangulation process described above can be operated in conjunction with a heat pump to heat the passenger cabin. For this purpose, as in the system shown in Figure 2, the condenser 240 is arranged to heat the passenger cabin. In contrast to the embodiment shown in Figure 2, the condenser 240 in the embodiment of Figure 6 is not integrated into the refrigerant circuit 200 via a three-way valve, but rather via an electronically controlled expansion valve 261, which is arranged downstream of the compressor 210 in the direction of refrigerant flow during heating operation. In the fluidic connection between the compressor 210 and the first heat exchanger 300, which can be a liquid-cooled condenser, another electronically controlled expansion valve 252 is arranged, via which refrigerant can be conducted to the first heat exchanger 300.Another electronically controlled expansion valve 262 integrates the evaporator 230 in cooling mode, and an electronically controlled expansion valve 263 is arranged upstream of the second heat exchanger in the flow direction.

[0090] The second heat exchanger 400, which may be a battery cooler, is arranged upstream of the compressor 210 or upstream of the accumulator 270 with respect to the flow direction of the refrigerant in heating mode, as already described in Figure 2.

[0091] Taking into account the valve arrangement, which is designed differently compared to the embodiment of Figure 2, the refrigerant flow in the temperature management system of Figure 6, as described above, can be circulated in the refrigerant circuit 200, bypassing the condenser 240 if necessary, in order to promote rapid heating of the same. If necessary, the arrangement of the expansion valves 252, 261 allows part or all of the heating power to be directed to the condenser 240.

[0092] With regard to the coolant circuit 100, Figure 6 shows a structure similar to the coolant circuit 100 described in Figure 4, but instead of a four-way valve 130 and three three-way valves 140, 150, 160, it has a first 1700 and a second proportionally controllable four-way valve 1800 as well as a three-way valve 118. Furthermore, Figure 6 explicitly shows further components of the coolant circuit 100, such as the ambient heat exchanger 110 and a three-way valve 118, by means of which the ambient heat exchanger can be integrated into the coolant circuit 100 or bypassed as needed. In addition, Figure 6 shows the integration of waste heat from the e-axis 112 in front of the first heat exchanger 300 as well as the position of two coolant pumps 115, 115' in front of the battery 500 and in front of the three-way valve 118.

[0093] As can be seen from Figure 6, the battery 500 is arranged between the first 1700 and the second four-way valve 1800, so that the coolant flow coming from the first heat exchanger 300 can be directed 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' that encloses the battery 500. In this way, the coolant temperature at the battery 500 can be adjusted as needed. To support rapid heating of the coolant circuit 100, the battery 500 can be bypassed, and the coolant triangulation process supports rapid heating of the coolant circuit 100 and the refrigerant circuit 200.

[0094] In contrast to Figure 6, Figure 7 shows a temperature management system 10 in which the coolant triangulation process described above is used in conjunction, but heating of the passenger cabin is not carried out via heat pump operation with condenser 240, but rather by a cabin heat exchanger 111 in the coolant circuit 100.

[0095] In the illustrated embodiment, 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, arranged downstream of the first heat exchanger 300, allows the refrigerant flow to be directed, as needed, entirely or partially via the evaporator and / or via the second heat exchanger 400 to the compressor 210, from which the refrigerant returns to the first heat exchanger 300. Alternatively, in embodiments of the invention, two electronic expansion valves are arranged instead of the three-way valve 255.

[0096] The coolant circuit 100 is fundamentally similar to the coolant circuit 100 shown in Figure 6, but includes a four-way valve 1900, a five-way valve 2000, and two three-way valves 118, 119 for directing the coolant as needed, with the second three-way valve 199 being optional. The ambient heat exchanger 110 is integrated or bypassed via the first three-way valve 118 as needed. The second three-way valve 119 directs the coolant coming from the first three-way valve 118 either to the four-way valve 1900 and from there to the first heat exchanger 300, or at least partially bypasses the first heat exchanger 300 and directs the coolant flow to the cabin heat exchanger 111 and the five-way valve 2000.

[0097] Starting from the five-way valve 2000, the coolant can be directed either back to the first three-way valve 118 or to a subcircuit 100', which, starting from the five-way valve 2000, includes the components of the second heat exchanger 400, the four-way valve 1900, and the battery 500 in sequence. Optionally, an electric heating element 120 can also be provided behind the five-way valve 2000.

[0098] The invention is not limited to the described and illustrated embodiments. Rather, it also encompasses all expert developments within the scope of the invention defined by the patent claims.

[0099] In addition to the embodiments described and illustrated, further embodiments are conceivable, which may include further modifications and combinations of features.

Claims

Claims 1 . Method for temperature management in a vehicle, in particular a battery-electric vehicle, the vehicle comprising a coolant circuit (100) for transporting coolant, wherein the coolant circuit (100) is thermally coupled to at least 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 to at least 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:

51. compressing the refrigerant in the compressor (210) while raising a temperature level of the refrigerant; 52. 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); 53. conveying the coolant at least from the first heat exchanger (300) to the second heat exchanger (400) and back to the first heat exchanger (300); 54. wherein in a heating operation, heat is transferred from the refrigerant to the coolant at the first heat exchanger (300) and heat is transferred from the coolant to the refrigerant at the second heat exchanger (400).

2. Method according to claim 1, characterized in that in step S3, heat from the coolant is released as needed and / or partially 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.

3. Method according to claim 1 or 2, characterized in that in step S3 heat is extracted from a vehicle environment using an ambient heat exchanger (110) and transferred to the coolant.

4. 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 transferred to the coolant.

5. Method according to one of claims 1 to 4, characterized in that in step S3 heat from waste heat of a drive unit of the vehicle is transferred to the coolant.

6. The method according to any one of claims 1 to 5, characterized in that in step S2, heat from the refrigerant is released as needed and / or partially to one or more further heat sinks which are thermally coupled to the refrigerant circuit (200), for example to a condenser (240) for heating a driver's cab of the vehicle or heating a refrigerant-cooled battery.

7. Method according to one of claims 1 to 6, characterized in that in step S2 heat from one or more heat sources is transferred to the refrigerant, for example ambient heat, waste heat from the compressor, or from additional electrical heating elements.

8. Method according to one of claims 1 to 7, characterized in that steps S1 to S4 are carried out until a temperature of the refrigerant at an outlet of the compressor (210) reaches a predetermined value.

9. Temperature management system (10) for a vehicle, in particular a battery-electric vehicle, comprising: a refrigerant circuit (200) for conducting a refrigerant, comprising at least one compressor (210) and a refrigerant feed pump; a coolant circuit (100) for conducting a coolant, wherein the coolant circuit (100) is thermally coupled to a battery (500) of the vehicle and comprises at least one coolant feed 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 to both the refrigerant circuit (200) and the coolant circuit (100);a second heat exchanger (400), in particular a battery cooler, which is thermally coupled to both the refrigerant circuit (200) and the coolant circuit (100) and, with respect to a flow direction of the refrigerant in a heating mode, is arranged downstream of the first heat exchanger (300) and upstream of the compressor (210); a controller which is control-technically connected to the coolant feed pump, the refrigerant feed 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; 10. Temperature management system (10) according to claim 9, characterized in that the coolant circuit (100) is thermally coupled to an ambient heat exchanger (110), via which heat is extracted from a vehicle environment and supplied to the coolant.

11. Temperature management system (10) according to one of claims 9 and 10, characterized in that the refrigerant circuit (200) is thermally connected to a condenser (240) for heating a driver's cab of the vehicle is coupled, wherein the condenser (240) is arranged behind the compressor (210) with respect to a flow direction of the refrigerant.

12. Temperature management system (10) according to claims 9 to 11, characterized in that the coolant circuit (100) comprises a four-way valve (130) which can be regulated by the controller as required and has two inlets (131, 132) and two outlets (133, 134), wherein: a first inlet (131) is fluidically connected to the first heat exchanger (300) and a first outlet (133) is fluidically connected to the second heat exchanger (400); a second inlet (132) receives a coolant flow from the direction of the thermal coupling with the battery (500).

13. Temperature management system (10) according to claim 12, characterized in that the second heat exchanger (400) is fluidically arranged 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 needed in the direction of the thermal coupling with the battery (500) and / or in the direction of the first heat exchanger (300).

14. Temperature management system (10) according to claim 13, characterized in that a second three-way valve (150) is fluidically arranged 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 needed and / or via the ambient heat exchanger (110) to the first heat exchanger (300).

15. Temperature management system (10) according to one of claims 12 to 14, characterized in that a second output (134) of the four-way valve (130) is fluidically connected to a third three-way valve (160), wherein the third three-way valve (160) has a Directs the coolant flow coming from the directional valve (130) as required in the direction of the thermal coupling with the battery (500) and / or in the direction of the second three-way valve (150).

16. Temperature management system (10) according to claim 15, characterized in that the coolant circuit (100) between the four-way valve (130) and the third three-way valve (160) is thermally coupled to an electrical heating element (120).

17. Temperature management system (10) according to one of claims 9 to 16, characterized in that an electrical heating element on the first heat exchanger (300) is thermally coupled to the coolant circuit (100).

18. Temperature management system (10) according to one 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 with the battery (500) is fluidically arranged between a second output (174) of the five-way valve (170) and a second input (182) of the four-way valve (180).

19. Temperature management system (10) according to claim 18, characterized in that a third output (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).

20. Temperature management system (10) according to one of claims 18 and 19, characterized in that the coolant circuit (200) is thermally coupled to an electrical heating element (120) between a second output (184) of the four-way valve (180) and a second input (172) of the five-way valve (170).

21. Temperature management system (10) according to one of claims 18 to 20, characterized in that an electrical heating element on the first heat exchanger (300) is thermally coupled to the coolant circuit (100).

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