Refrigerant system, distribution module and thermal management system for an electric vehicle

Abstract

The present invention relates to a refrigerant system (2) for an electric vehicle, comprising the following components: a compressor (4), at least one condenser (6, 8), at least one expansion device (10, 12) and an evaporator (14), the aforementioned components interacting in the manner of a heat pump when the refrigerant system (2) is in an operating state, characterized in that the refrigerant system (2) has a distribution module (20) for fluidically connecting the aforementioned components and for distributing a refrigerant circulating in the refrigerant system (2), the distribution module (20) comprising a first module part (22) disposed fluidically between a compressor outlet of the compressor (4) and a condenser inlet of the at least one condenser (6, 8) and a second module part (24) disposed fluidically between a condenser outlet of the at least one condenser (6, 8) and a compressor inlet of the compressor (4), and the first module part (22) being substantially thermally insulated from the second module part (24) by means of at least one insulating part (26) of the distribution module (20).

Description

[0001] Refrigerant system, distribution module and thermal management system for an electric vehicle

[0002] Description

[0003] The present invention relates to a refrigerant system of the type mentioned in the preamble of claim 1, a distribution module for a refrigerant system and a thermal management system for an electric vehicle of the type mentioned in the preamble of claim 8.

[0004] Such thermal management systems for electric vehicles with a refrigerant system and a coolant system are already known from the prior art in numerous design variants. The known coolant systems for circulating a liquid coolant comprise a plurality of components through which the coolant can flow, wherein the components can be connected to one another, at least in at least one subset, in a coolant-conducting manner by means of valves and coolant lines. The same applies to the known refrigerant systems for circulating a refrigerant, comprising the following components: a compressor, at least one condenser, at least one expansion device, and an evaporator. The aforementioned components interact in an operating state of the refrigerant system in the manner of a heat pump.However, complex thermal management systems, such as those required in modern electric vehicles, require a very large number of valves and coolant lines, as well as valves and refrigerant lines, at the current state of the art. Such systems require a lot of space and are expensive. Furthermore, the efficiency of these existing thermal management systems requires improvement.

[0005] This is where the present invention comes in. The present invention is based on the object of improving a refrigerant system, a distribution module, and a thermal management system for an electric vehicle with a coolant system and a refrigerant system.

[0006] This object is achieved by a refrigerant system for an electric vehicle with the features of claim 1, which is characterized in that the refrigerant system has a distribution module for the flow-conducting connection of the aforementioned components and for the distribution of a refrigerant circulating in the refrigerant system, wherein the distribution module has a first module part fluidically arranged between a compressor outlet of the compressor and a condenser inlet of the at least one condenser and a second module part fluidically arranged between a condenser outlet of the at least one condenser and a compressor inlet of the compressor, and wherein the first module part is substantially thermally insulated from the second module part by means of at least one insulating part of the distribution module.Furthermore, this problem is solved by a distribution module having the features of claim 3 and a thermal management system for an electric vehicle having the features of claim 8. The subclaims relate to advantageous developments of the invention.

[0007] A significant advantage of the invention lies in the fact that a refrigerant system, a distribution module, and a thermal management system for an electric vehicle comprising a coolant system and a refrigerant system are improved. Due to the invention, functionally complex refrigerant systems and thermal management systems for electric vehicles can be implemented in a simpler design and manufacturing manner. Accordingly, the structure of the refrigerant system according to the invention and thus of the thermal management system according to the invention is significantly simplified, so that these systems can be manufactured cost-effectively and in a space-saving manner. At the same time, the efficiency of such refrigerant systems and thermal management systems is increased by means of the invention.This is because it is advantageous for the respective system efficiency to essentially thermally separate the high-temperature region upstream of the at least one condenser from the low-temperature region, while a thermal connection of the high-temperature region downstream of the at least one condenser with the low-temperature region downstream of the evaporator can be advantageous. Accordingly, a simply constructed system with few components, valves, and refrigerant lines can, in principle, realize a multitude of operating states, i.e., operating modes of the system, while simultaneously ensuring high efficiency of the refrigerant system and thus of the thermal management system.

[0008] In principle, the thermal management system for an electric vehicle according to the invention and the refrigerant system for an electric vehicle according to the invention can each be freely selected within wide, suitable limits in terms of type, mode of operation, material, and dimensions. Furthermore, the invention is not limited to application in purely electric vehicles. For example, the invention can also be advantageously used in so-called hybrid vehicles.

[0009] A particularly advantageous development of the refrigerant system according to the invention provides that the first module part, the at least one insulating part and the second module part can be connected to form a structural unit forming the distribution module. Preferably, this connection is made by means of one of the aforementioned components of the refrigerant system, particularly preferably, this component is designed as one of the at least one condenser. This significantly simplifies the structural and manufacturing design of the refrigerant system according to the invention. This applies particularly to the preferred and in particular to the particularly preferred embodiment of this development, since the aforementioned component, designed, for example, as one of the condensers, simultaneously serves as a connecting element for mechanically connecting the first module part, the at least one insulating part and the second module part to produce the aforementioned structural unit.In principle, the distribution module according to the invention for the refrigerant system according to the invention can also be freely selected within wide limits in terms of type, mode of operation, material, dimensioning and arrangement.

[0010] An advantageous development of the distribution module according to the invention provides that at least one valve of the distribution module, preferably a valve of the distribution module designed as a single multi-way valve, is arranged in the first module part. In this way, the aforementioned valve, in particular the valve designed as a single multi-way valve, is substantially thermally insulated from the second module part.

[0011] A further advantageous development of the distribution module according to the invention provides for an internal heat exchanger, also referred to as an IHX, to be arranged in the second module part. The internal heat exchanger is designed and arranged in such a way that, by means of the internal heat exchanger, heat exchange is enabled between a refrigerant line arranged fluidically upstream of the evaporator and a refrigerant line arranged fluidically downstream of the evaporator. This enables an advantageous thermal connection between the high-temperature region and the low-temperature region of the refrigerant system in the second module part.It is conceivable, for example, that for this purpose at least one refrigerant line of the low-temperature region designed as a return line downstream of the evaporator is arranged only in spatial proximity to at least one refrigerant line of the high-temperature region downstream of the at least one condenser, so that an advantageous heat transfer between these two regions of the refrigerant system according to the invention can be produced in a very simple manner in terms of design and production technology.

[0012] Another advantageous development of the distribution module according to the invention provides that at least one of the at least one expansion device, preferably an expansion device designed as an expansion valve, is arranged in the second module part. In this way, the concentration level of components of the refrigerant system according to the invention is further increased in the distribution module according to the invention. In this context, arranging all expansion devices in the second module part would be particularly advantageous.

[0013] In principle, the at least one insulating part of the distribution module according to the invention can be freely selected in terms of type, mode of operation, material, dimensions, and arrangement within wide suitable limits. An advantageous development of the distribution module according to the invention provides that at least one of the at least one insulating part has an opening for the passage of a refrigerant line of the distribution module, preferably that this refrigerant line is fluidly connectable to the multi-way valve, particularly preferably that this refrigerant line is fluidly connected to a refrigerant line of the distribution module that is fluidly connected to the compressor inlet of the compressor. As a result, despite the essentially thermal insulation of the first module part from the second module part, a required fluidly conductive connection of the distribution module according to the invention is made possible by the thermal insulation.The preferred and especially the particularly preferred embodiment of this refinement provide particularly advantageous flow-conducting connections between the first module part on one side of the insulating part and the second module part on the other side of the insulating part. This opening in the thermal insulation can be thermally sealed using means and measures suitable for the respective application, with the exception of the aforementioned flow-conducting connection. Suitable means and measures for this are known to those skilled in the art, depending on the requirements of the individual case.

[0014] As already explained above, the thermal management system according to the invention can be freely selected within wide suitable limits.

[0015] An advantageous development of the thermal management system according to the invention provides that one of the at least one condenser is designed as a liquid-cooled condenser, wherein this condenser can be connected to the coolant system in a flow-conducting manner. By means of the condenser, a heat transfer connection can thus be established as required between the coolant system on the one side and the refrigerant system on the other side. For example, the condenser can be arranged in a coolant-conducting manner in a drive train sub-circuit of the coolant system. The condenser, a component present in a conventional refrigerant system for an electric vehicle, can therefore be used both for the operation of the refrigerant system and for heat transfer between the coolant system on the one side and the refrigerant system on the other side.

[0016] Alternatively or in addition to the aforementioned embodiment, a further advantageous development of the thermal management system according to the invention provides that the distribution module can be connected in a flow-conducting manner to a chiller of the thermal management system, wherein the chiller enables heat exchange between the refrigerant system on the one side and the coolant system on the other side. By means of the chiller, a heat transfer connection can thus be established as required between the coolant system on the one side and the refrigerant system on the other side. Accordingly, this results in advantages that are comparable to those of the aforementioned development of the thermal management system according to the invention. In combination, the two aforementioned developments of the thermal management system according to the invention also result in the possibility of exchanging even more energy between the coolant system and the refrigerant system.On the other hand, the flexibility of the thermal management system according to the invention is thereby further increased.

[0017] The invention is explained in more detail below using the attached, roughly schematic drawing. It shows:

[0018] Fig. 1 shows an embodiment of the refrigerant system according to the invention with the distribution module according to the invention in a process diagram, Fig. 2 shows the distribution module of the embodiment according to Fig. in one

[0019] Dismantling position,

[0020] Fig. 3 the distribution module of the embodiment according to Fig. in one

[0021] Intermediate layer and

[0022] Fig. 4 the distribution module of the embodiment according to Fig. in one

[0023] Mounting position.

[0024] In Figures 1 to 4, an embodiment of the refrigerant system according to the invention of a thermal management system according to the invention (not shown in detail) is shown purely by way of example.

[0025] The thermal management system is designed as a thermal management system for a purely electric vehicle and comprises, on the one hand, a coolant system (not shown) and, on the other hand, a refrigerant system 2. The coolant system for circulating a liquid coolant here comprises a plurality of components through which the coolant can flow, wherein the components can be connected to one another in a coolant-conducting manner, at least in at least one subset, by means of at least one valve, for example a multi-way valve, and by means of coolant lines.

[0026] The refrigerant system 2 is designed for air conditioning a passenger compartment of the electric vehicle (also not shown) and for controlling the temperature of a coolant (not shown) flowing in the coolant system. The refrigerant system 2 is shown in Fig. 1, wherein the refrigerant system 2 comprises the following components: a compressor 4, a first condenser 6 and a second condenser 8, a first expansion device 10 and a second expansion device 12, and an evaporator 14, wherein the aforementioned components interact in an operating state of the refrigerant system 2 in the manner of a heat pump. The second condenser 8 is designed here as a liquid-cooled condenser, wherein this condenser 8 can be fluidly connected to the coolant system in a manner known per se to those skilled in the art.The second condenser 8 can thus be indirectly connected to a free environment via the liquid coolant for heat transfer. The first condenser 6 and the evaporator 14 are designed here as a so-called interior condenser and as a so-called interior evaporator, respectively, and thus each have direct heat exchange with the passenger compartment. The evaporator 14 and the first condenser 6 allow both direct cooling and heating of the interior of the electric vehicle, namely the passenger compartment. The heat pump, i.e., the refrigerant system 2, enables heating functions with a COP of 1. Thus, for a given heating output, only a fraction of this heating output needs to be provided as electrical power.

[0027] Furthermore, the refrigerant system 2 in the present embodiment comprises a chiller 16 and an accumulator 18. The chiller 16 also enables heat exchange between the refrigerant system 2 on the one side and the coolant system on the other side. For this purpose, the chiller 16, analogous to the second condenser 8, can be fluidly connected to the coolant system in a manner known per se to those skilled in the art. The accumulator 18 serves here as a storage container for the refrigerant (not shown) of the refrigerant system 2. However, other embodiments of storage containers for the refrigerant are also conceivable.

[0028] According to the invention, the refrigerant system 2 has a distribution module 20 for the flow-conducting connection of the aforementioned components and for distributing a refrigerant circulating in the refrigerant system 2, wherein the distribution module 20 has a first module part 22 fluidically arranged between a compressor outlet of the compressor 4 and a condenser inlet of the respective condenser 6, 8 and a second module part 24 fluidically arranged between a condenser outlet of the respective condenser 6, 8 and a compressor inlet of the compressor 4, and wherein the first module part 22 is substantially thermally insulated from the second module part 24 by means of an insulating part 26 of the distribution module 20. The refrigerant is not shown in Figs. 1 to 4.In the present embodiment, the first module part 22, the insulating part 26, and the second module part 24 can be connected to form a structural unit forming the distribution module 20, with this connection being made by means of one of the aforementioned components of the refrigerant system 2, namely the second condenser 8. See Figs. 2 to 4 for an overview.

[0029] A valve 28 of the distribution module 20, designed as a multi-way valve, is arranged in the first module part 22. Furthermore, an internal heat exchanger 30 is arranged in the second module part 24. The internal heat exchanger 30 is designed and arranged such that, by means of the internal heat exchanger 30, heat exchange is possible between a refrigerant line 32 arranged fluidically upstream of the evaporator 14 and a refrigerant line 34 arranged fluidically downstream of the evaporator 14. Furthermore, the first expansion device 10, designed as a first expansion valve, and the second expansion device 12, designed as a second expansion valve, are each arranged in the second module part 24.

[0030] In the present embodiment, the insulating part 26 has an opening 36 for the passage of a refrigerant line 38 of the distribution module 20, wherein this refrigerant line 38 is fluidly connectable to the multi-way valve 28 and that this refrigerant line 38 is fluidly connected to the refrigerant line 34 of the distribution module 20, which is fluidly connected to the accumulator 18 and thus indirectly to the compressor inlet of the compressor 4.

[0031] In the following, the functioning of the thermal management system according to the invention with the refrigerant system according to the invention and the distribution module according to the invention according to the present embodiment is explained in more detail with reference to Figs. 1 to 4.

[0032] According to the present exemplary embodiment, the assembly of the refrigerant system 2 with the distribution module 20 is significantly simplified compared to the prior art. The first module part 22, the insulating part 26, and the second module part 24 of the distribution module 20 are connected to one another and held in contact by the second condenser 8. See Figs. 2 to 4 for an overview. The insulating part 26 can, for example, be pre-assembled either on the first module part 22 or on the second module part 24 in order to further simplify production. The first module part 22 and the second module part 24 are then assembled and connected by means of the second condenser 8 to form the distribution module 20, which is designed as a single structural unit.The aforementioned connection, for example by screwing or the like, of the second capacitor 8 with the first module part 22 and the second module part 24 generates the necessary contact force so that sealing points at interfaces between the first module part 22, the second module part 24 and the insulating part 26 are effectively sealed.

[0033] This fixes the insulating part 26 between the first module part 22 and the second module part 24, eliminating the need for direct connection points between the insulating part 26, on the one hand, and the first module part 22 and the second module part 24, on the other hand, connecting the high-temperature region of the first module part 22 and the low-temperature region of the second module part 24. This further reduces undesirable heat transfer between the first module part 22 and the second module part 24.

[0034] Depending on the operating state of the thermal management system with the refrigerant system 2 and taking into account the driving situation and the ambient temperature, the components of the coolant system (not shown in detail) can represent heat sources or heat sinks.

[0035] Essentially, the refrigerant system 2 comprises the aforementioned high-pressure / high-temperature region (HT region for short) and the aforementioned low-pressure / low-temperature region (LT region for short). The HT region comprises the region between the compressor outlet of the compressor 4 and the multi-way valve 28, then either to the first condenser 6 and / or the second condenser 8, and then to the expansion valves 10 and 12. The LT region begins after the expansion valves 10, 12 and comprises the region from the expansion valves 10, 12 to the chiller 16 and the evaporator 14, then to the accumulator 18, and finally to the compressor inlet of the compressor 4.With regard to system efficiency, it is advantageous to thermally separate the HT region upstream of the condensers 6, 8 from the NT region downstream of the condensers 6, 8, while a thermal connection of the HT region downstream of the condensers 6, 8 and the NT region downstream of the evaporator 14 may be advantageous for system efficiency.

[0036] By means of the distribution module 20, the components of the refrigerant system 2 are at least partially integrated into a single module. Furthermore, the distribution module 20 enables advantageous thermal separation / connection of the HT and LT regions, as explained above. In Fig. 1, external refrigerant lines, i.e., refrigerant lines beyond the distribution module 20, are shown by dashed lines, and refrigerant lines within the distribution module 20 are shown by solid lines. The first module part 22 comprises the HT region upstream of the condensers 6, 8, which contains the flow-conducting connections from the compressor 4 to the multi-way valve 28 and to the condensers 6, 8.

[0037] The second module part 24 comprises the high-temperature region downstream of the condensers 6, 8 and the low-temperature region. The return line of the low-temperature region downstream of the evaporator 14, namely the refrigerant line 34, is arranged in such close proximity to the refrigerant line 32 of the high-temperature region downstream of the condensers 6, 8 that an advantageous heat transfer between these two regions can be achieved in the internal heat exchanger 30 formed in this way. The internal heat exchanger 30, implemented solely in the aforementioned manner, is indicated by a dot-dash line in Figs. 1 to 4. Of course, other embodiments of the internal heat exchanger, if present, are also conceivable.

[0038] The efficiency of the overall system, i.e., the thermal management system with the coolant system and the refrigerant system 2, can be improved by connecting or disconnecting the individual components of the refrigerant system as needed. According to the invention, this is achieved while maintaining high overall system efficiency. The second condenser 8 and the chiller 16 allow the coolant system on one side and the refrigerant system 2 on the other side to be connected for heat transfer.

[0039] The invention is not limited to the present embodiment. See, for example, the relevant statements in the introduction to the description and in the description of the specific embodiment regarding alternative or optional technical features of the invention.

[0040] List of reference symbols

[0041] 2 Refrigerant system

[0042] 4 Compressor

[0043] 6 First capacitor

[0044] 8 Second capacitor

[0045] 10 First relaxation device

[0046] 12 Second relaxation device

[0047] 14 evaporators

[0048] 16 chillers

[0049] 18 Accumulator

[0050] 20 distribution module

[0051] 22 First module part

[0052] 24 Second module part

[0053] 26 Insulating part

[0054] 28 Multi-way valve

[0055] 30 Internal heat exchanger

[0056] 32 Refrigerant line

[0057] 34 Refrigerant line

[0058] 36 Opening in the insulating part 26

[0059] 38 Refrigerant line

Claims

Patent claims 1. Refrigerant system (2) for an electric vehicle, comprising the following components: a compressor (4), at least one condenser (6, 8), at least one expansion device (10, 12) and an evaporator (14), wherein the aforementioned components interact in an operating state of the refrigerant system (2) in the manner of a heat pump, characterized in that the refrigerant system (2) has a distribution module (20) for the flow-conducting connection of the aforementioned components and for the distribution of a refrigerant circulating in the refrigerant system (2), wherein the distribution module (20) has a first module part (22) fluidically arranged between a compressor outlet of the compressor (4) and a condenser inlet of the at least one condenser (6, 8) and a second module part (24) fluidically arranged between a condenser outlet of the at least one condenser (6, 8) and a compressor inlet of the compressor (4),and wherein the first module part (22) is substantially thermally insulated from the second module part (24) by means of at least one insulating part (26) of the distribution module (20).

2. Refrigerant system (2) according to claim 1, characterized in that the first module part (22), the at least one insulating part (26) and the second module part (24) can be connected to form a unit forming the distribution module (20), preferably that this connection is made by means of one of the aforementioned components of the refrigerant system (2), particularly preferably that this component is designed as one of the at least one condenser (8). Distribution module (20) for a refrigerant system (2) according to claim 1 or 2, characterized in that the first module part (22), the at least one insulating part (26), and the second module part (24) are configured such that the first module part (22), the at least one insulating part (26), and the second module part (24) can be connected to one another to form a unit constituting the distribution module (20). Distribution module (20) according to claim 3, characterized in that at least one valve of the distribution module (20), preferably a valve (28) of the distribution module (20) configured as a single multi-way valve, is arranged in the first module part (22).Distribution module (20) according to claim 3 or 4, characterized in that an internal heat exchanger (30) is arranged in the second module part (24), wherein the internal heat exchanger (30) is designed and arranged such that heat exchange is enabled by means of the internal heat exchanger (30) between a refrigerant line (32) arranged upstream of the evaporator (14) and a refrigerant line (34) arranged downstream of the evaporator (14). Distribution module (20) according to any one of claims 3 to 5, characterized in that at least one expansion device, preferably an expansion device (10, 12) designed as an expansion valve, is arranged in the second module part (24). Distribution module (20) according to any one of claims 3 to 6. characterized in that at least one of the at least one insulating part (26) has an opening (36) for the passage of a refrigerant line (38) of the distribution module (20), preferably that this refrigerant line (38) can be flow-conducted to the multi-way valve (28), particularly preferably that this refrigerant line (38) is flow-conducted to a refrigerant line (34) of the distribution module (20) which is flow-conducted to the compressor inlet of the compressor (4). Thermal management system for an electric vehicle, comprising on the one hand a refrigerant system (2) for circulating a refrigerant and on the other hand a coolant system connectable to the refrigerant system (2) for heat transfer to circulate a liquid coolant, characterized in that the refrigerant system (2) is configured according to claim 1 or 2.Thermal management system according to claim 8, characterized in that one of the at least one condenser is designed as a liquid-cooled condenser (8), wherein this condenser (8) is flow-conducting and can be connected to the refrigerant system. Thermal management system according to claim 8 or 9, characterized in that the distribution module (20) is flow-conducting and can be connected to a chiller (16) of the thermal management system, wherein the chiller (16) enables heat exchange between the refrigerant system (2) on one side and the refrigerant system on the other side.

Images