DE102017004965A1 - Temperierungskreislauf for a motor vehicle, method for operating a Temperierungskreislaufs and motor vehicle - Google Patents

Abstract

The invention relates to a Temperierungskreislauf (10) for a motor vehicle, which is flowed through by a medium, with a compressor (12), with a downstream of the compressor (12) arranged first heat exchanger (14), by means of which an air flow (70) for a Vehicle interior of the motor vehicle is heated, with a downstream of the first heat exchanger (14) arranged second heat exchanger (38) for cooling the air flow (70) with a downstream of the first heat exchanger (14) arranged third heat exchanger (42) for temperature control of a battery of the motor vehicle , with at least one fourth heat exchanger (60) arranged downstream of the second heat exchanger (42), by means of which heat can be transferred from its environment to the medium, with a first expansion device (FIG. 3) between the first heat exchanger (14) and the second heat exchanger (38). 16), with a between the second heat exchanger (38) and the fourth heat exchanger (60) a second expansion device (40), and with a third expansion device (44) arranged downstream of the third heat exchanger (42), wherein the second heat exchanger (38) and the third heat exchanger (42) and the second expansion device (40) and the third expansion device ( 44) downstream of the first heat exchanger (14) and upstream of the fourth heat exchanger (60) are each connected in parallel to each other.

Description

The invention relates to a Temperierungskreislauf for a motor vehicle, a method for operating a Temperierungskreislaufs and a motor vehicle according to the preambles of the independent claims.

From the US 2013/0025311 A1 are such a medium permeable by a medium tempering circuit for a motor vehicle and such a method for operating the Temperierungskreislaufs already known. The tempering circuit comprises a compressor, and a first heat exchanger arranged downstream of the compressor in the flow direction of the medium, by means of which a stream of air for a vehicle interior of the motor vehicle can be heated. In addition, the temperature control circuit has a second heat exchanger arranged downstream of the first heat exchanger for cooling the air flow. Downstream of the first heat exchanger, a third heat exchanger is also provided for controlling the temperature of a battery of the motor vehicle, and at least one fourth heat exchanger arranged downstream of the second heat exchanger, by means of which heat can be transferred from its environment to the medium. For tempering the battery, the third heat exchanger is thermally coupled to a battery circuit, so that heat can be exchanged between the battery circuit and the third heat exchanger. By means of the battery circuit heat can be exchanged between the battery of the motor vehicle and the third heat exchanger.

Between the first heat exchanger and the second heat exchanger, a first expansion device is arranged, between the second heat exchanger and the fourth heat exchanger, a second expansion device is arranged, and downstream of the third heat exchanger, a third expansion device is arranged. By means of the respective expansion devices, the medium can be expanded from a high pressure level to a medium pressure level and / or a low pressure level. The arrangement of the respective expansion device between respective heat exchangers does not necessarily mean a local arrangement of the expansion device, but rather that the respective expansion device is arranged upstream of the one heat exchanger and downstream of the respective other heat exchanger.

The medium is compressed by the compressor when flowing through the Temperierungskreislauf and flows downstream of the compressor through the first heat exchanger, via which passes to heat the air flow for the vehicle interior of the motor vehicle heat from the medium to the air flow. Subsequently, the medium flows through the second heat exchanger arranged downstream of the first heat exchanger, by means of which heat is transferred from the air flow to the medium for cooling the air flow. Furthermore, the medium flows through the third heat exchanger downstream of the first heat exchanger, via which the battery of the motor vehicle is temperature controlled by the medium and arranged downstream of the second heat exchanger fourth heat exchanger, by means of which heat is transferred from its environment to the medium. In addition, the medium flows through the first expansion device arranged between the first heat exchanger and the second heat exchanger, the second expansion device arranged between the second heat exchanger and the fourth heat exchanger and the third expansion device arranged downstream of the third heat exchanger, by means of which the medium is expanded in each case.

Furthermore, from the DE 102 53 357 A1 a combined refrigeration / heat pump for use in motor vehicles for cooling, heating and dehumidifying a vehicle interior known. The combined refrigeration system / heat pump can be operated in a cooling mode in which an air flow for the vehicle interior is cooled, in a heating mode in which the air flow for the vehicle interior is heated, and in a dehumidification heating mode. In the dehumidification heating mode, the air flow for dehumidification is first cooled, then heated and then supplied to the vehicle interior.

Object of the present invention is to provide a Temperierungskreislauf for a motor vehicle, a method for operating a Temperierungskreislaufs for a motor vehicle and a motor vehicle, by means of which a plurality of components of the motor vehicle are particularly advantageous tempered.

This object is achieved by a Temperierungskreislauf for a motor vehicle, by a method for operating a Temperierungskreislaufs for a motor vehicle and by a motor vehicle having the features of the independent claims.

To create a tempering circuit for a motor vehicle of the type mentioned, by means of which several components of the motor vehicle are particularly advantageous tempered, it is inventively provided that the second heat exchanger and the third heat exchanger and the second expansion device and the third expansion device downstream of the first heat exchanger and upstream of the fourth heat exchanger are each connected in parallel to each other. This means that after flowing through the first heat exchanger and the first expansion device, the medium can be divided into a first partial flow and a second partial flow. The first partial flow can flow through the second heat exchanger, wherein parallel or simultaneously to the second partial flow can flow through the third heat exchanger. The partial flows or the second and third heat exchangers are thus connected fluidically parallel to each other.

The first expansion device is arranged in particular upstream of a branch of the medium in the first partial flow and the second partial flow. The second heat exchanger can be flowed through by the first partial flow, while the third heat exchanger can simultaneously flow through the second partial flow of the medium. Downstream of the second heat exchanger and the third heat exchanger, the second expansion device and the third expansion device can be flowed through in parallel by the respective partial flows. In particular, the first partial flow flows through the second expansion device, while at the same time or in parallel the second partial flow flows through the third expansion device. After flowing through the second expansion device and the third expansion device, for example, the first partial flow and the second partial flow of the medium combine downstream of the second expansion device and the third expansion device, in particular in a collecting device.

The first partial flow and the second partial flow flow together through the fourth heat exchanger downstream of the collecting device. In an alternative embodiment, upstream of the second heat exchanger and the third heat exchanger and downstream of the first heat exchanger, a plurality of expansion devices may be connected in parallel.

An advantage of the parallel connection of the second heat exchanger and the third heat exchanger and the second expansion device and the third expansion device is that depending on the configuration of the branch for dividing the medium into the first partial flow and the second partial flow of the battery, for example via a battery circuit, and the air flow can be tempered independently. The medium can be passed completely through the second heat exchanger or completely through the third heat exchanger or split into the respective partial flows and flow through the second heat exchanger and the third heat exchanger in parallel. This results in the advantage that the air flow and the battery independently of each other are particularly easy to temper by means of the Temperierungskreislaufes.

It has proved to be advantageous if a fifth heat exchanger, by means of which heat from a drive train of the motor vehicle can be transferred to the medium, and a fourth expansion device arranged downstream of the fifth heat exchanger are provided. The fifth heat exchanger and the fourth expansion device are connected downstream of the first heat exchanger and upstream of the fourth heat exchanger in parallel to the second heat exchanger, the third heat exchanger, the second expansion device and the third expansion device. This means that the second heat exchanger, the third heat exchanger and the fifth heat exchanger are each connected in parallel to each other and the second expansion device, the third expansion device and the fourth expansion device are also connected in parallel to each other. The fifth heat exchanger can be flowed through by a third partial flow of the medium, which is diverted in particular by means of the branch. Thus, advantageously by means of the fifth heat exchanger flowing through the third partial flow of the medium, the drive train of the motor vehicle can be cooled and the third partial flow of the medium flowing through the fifth heat exchanger can be heated. Advantageously, heat can thus be introduced into the tempering circuit via the fifth heat exchanger.

According to an advantageous development of the invention, a sixth heat exchanger is provided which can be flowed through by a first medium flow flowing toward the fourth heat exchanger and by a second medium flow flowing toward the compressor, heat being exchangeable between the medium flows via the sixth heat exchanger. In other words, an internal heat exchanger is provided, by means of which heat can be transferred from a first region of the tempering circuit to another, second region of the tempering circuit. In this case, the first region is arranged downstream of the second expansion device, the third expansion device and the fifth expansion device and upstream of the fourth heat exchanger and the second region is arranged downstream of the fourth heat exchanger and upstream of the compressor. Advantageously, heat can thus be shifted between the regions in order to obtain a particularly high degree of effectiveness of the tempering circuit.

Preferably, downstream of the fourth heat exchanger and upstream of the compressor, a separator for separating the medium in its liquid phase and in its gas phase is arranged. The medium can thus be separated into its liquid phase and into its gas phase after flowing through the fourth heat exchanger and before flowing through the compressor in the separator. This can advantageously be ensured that the medium is compressed in its gas phase of the compressor. By supplying the medium in its gas phase to the compressor, for example, a phase change of the medium in the compressor can be restricted and thus a life of the compressor can be increased particularly advantageous.

In a further advantageous embodiment of the invention, a bypass is provided, by means of which the medium after flowing through the first expansion device to the second heat exchanger, the third heat exchanger, the fourth heat exchanger and the fifth heat exchanger past the compressor can be fed. The bypass is a bypass line, which can be flowed through by the medium, bypassing the second heat exchanger, the third heat exchanger, the fourth heat exchanger and the fifth heat exchanger. In particular, by means of the bypass, a fourth partial flow of the medium can be supplied to the compressor past the second heat exchanger, the third heat exchanger, the fourth heat exchanger and the fifth heat exchanger. Thus, by means of the branching, the medium can be divided into the first partial flow and / or the second partial flow and / or the third partial flow and / or the fourth partial flow. This results in the advantage that can be set, in particular controlled or regulated, can be, whether and by which of the heat exchanger heat is transferred to the medium or discharged from the medium.

Preferably, the medium is formed as carbon dioxide, which is also referred to as refrigerant R744. Advantageously, carbon dioxide is a non-flammable, easy-to-use and cost-effective refrigerant.

To provide a method for operating a Temperierungskreislaufs for a motor vehicle of the type mentioned, with which a plurality of components of the motor vehicle are particularly easy tempered, the invention provides that the second heat exchanger and the third heat exchanger and the second expansion device and the third expansion device downstream of the first Heat exchanger and upstream of the fourth heat exchanger are each connected in parallel to each other, so that the medium in each case flows through the second heat exchanger and the third heat exchanger and the second expansion device and the third expansion device in parallel. In other words, flows through a first partial flow of the medium, the second heat exchanger and a second partial flow of the medium parallel to the third heat exchanger. Subsequently, the first partial flow flows through the second expansion device and the second partial flow through the third expansion device in parallel. Advantageously, both the battery and the air flow can thus be tempered in parallel by means of the medium.

In an advantageous embodiment of the invention, a fifth heat exchanger, by means of which heat from a drive train of the motor vehicle is transferred to the medium, and a downstream of the fifth heat exchanger arranged fourth expansion means are provided, by means of which the medium is expanded, wherein the fifth heat exchanger and the fourth Expansion means are connected downstream of the first heat exchanger and upstream of the fourth heat exchanger in parallel to the second heat exchanger, the third heat exchanger, the second expansion device and the third expansion device. In other words, the second heat exchanger of the first partial flow, the third heat exchanger of the second partial flow and the fifth heat exchanger of the third partial flow can be flowed through in parallel. For example, one, two or three of the heat exchangers connected in parallel to one another can be flowed through by a respective partial flow of the medium at the same time. Advantageously, a parallel temperature control of the drive train, the battery and the air flow can thus be controlled by means of the parallel-connected heat exchangers.

In a further advantageous embodiment of the invention, it is provided that the medium flows through the third heat exchanger with heat release to the battery of the motor vehicle after flowing through the first heat exchanger. This means that the medium emits heat to the air stream after its compression by the compressor in the first heat exchanger and then emits heat to the battery or the aforementioned battery circuit when flowing through the third heat exchanger, so that the battery can be heated by means of the heat given to the battery circuit , For example, the medium is not relaxed during flow through the first expansion device and at least substantially maintains its pressure level. This results in the advantage that, for example, when starting the motor vehicle and / or at low outside temperatures, the battery can be heated to its operating temperature very quickly.

Furthermore, the invention relates to a motor vehicle with a Temperierungskreislauf, as has been explained in connection with the Temperierungskreislauf invention. The motor vehicle is designed to carry out a method as has been explained in connection with the method according to the invention.

Further advantages, features and details of the invention will become apparent from the the following description of a preferred embodiment and with reference to the drawing. The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the respectively specified combination but also in other combinations or in isolation, without the scope of To leave invention.

• 1 ein Fließschema eines Temperierungskreislaufs, bei welchem ein zweiter Wärmetauscher, ein dritter Wärmetauscher und ein fünfter Wärmetauscher parallel zueinander geschaltet sind, in einem ersten Betriebszustand, in welchem der zweite Wärmetauscher von einem ersten Teilstrom und der dritte Wärmetauscher von einem zweiten Teilstrom eines Mediums parallel durchströmt werden;
• 2 eine schematische Ansicht eines Druck-Enthalpie-Diagramms mit einem ersten Zustandskreislauf des Mediums gemäß dem ersten Betriebszustand des Temperierungskreislaufs aus 1;
• 3 das Fließschema des Temperierungskreislaufs in einem zweiten Betriebszustand, in welchem das Medium den dritten Wärmetauscher durchströmt und den zweiten Wärmetauscher und den fünften Wärmetauscher umgeht, das bedeutet nicht durchströmt;
• 4 die schematische Ansicht des Druck-Enthalpie-Diagramms mit einem zweiten Zustandskreislauf des Mediums gemäß dem zweiten Betriebszustand des Temperierungskreislaufs aus 3;
• 5 das Fließschema des Temperierungskreislaufs in einem dritten Betriebszustand, in welchem der zweite Wärmetauscher von einem ersten Teilstrom und der fünfte Wärmetauscher von einem dritten Teilstrom des Mediums parallel durchströmt werden; und
• 6 das Fließschema des Temperierungskreislaufs in einem vierten Betriebszustand, in welchem das Medium vollständig durch den dritten Wärmetauscher strömt und hierbei eine Batterie des Kraftfahrzeugs kühlt, während der zweite Wärmetauscher und der fünfte Wärmetauscher von dem Medium umgangen, das bedeutet nicht durchströmt werden.

Showing:

• 1 a flow diagram of a Temperierungskreislaufs, in which a second heat exchanger, a third heat exchanger and a fifth heat exchanger are connected in parallel, in a first operating state in which the second heat exchanger by a first partial flow and the third heat exchanger are flowed through in parallel by a second partial flow of a medium ;
• 2 a schematic view of a pressure-enthalpy diagram with a first state circuit of the medium according to the first operating state of the Temperierungskreislaufs from 1 ;
• 3 the flow diagram of the Temperierungskreislaufs in a second operating state in which the medium flows through the third heat exchanger and bypasses the second heat exchanger and the fifth heat exchanger, that does not flow through;
• 4 the schematic view of the pressure-enthalpy diagram with a second state circuit of the medium according to the second operating state of the Temperierungskreislaufs from 3 ;
• 5 the flow diagram of the Temperierungskreislaufs in a third operating state, in which the second heat exchanger by a first partial flow and the fifth heat exchanger are flowed through in parallel by a third partial flow of the medium; and
• 6 the flow diagram of the Temperierungskreislaufs in a fourth operating state in which the medium flows completely through the third heat exchanger, thereby cooling a battery of the motor vehicle, while the second heat exchanger and the fifth heat exchanger bypassed by the medium, that is, not flowed through.

Corresponding elements are provided in all figures with the same reference numerals.

In 1 . 3 . 5 and 6 is a tempering circuit 10 shown for a motor vehicle not shown in different operating states. By means of the temperature control circuit 10 Heat can be particularly beneficial between a powertrain, a battery and an airflow 70 be shifted for a vehicle interior of the motor vehicle, which means that by means of the Temperierungskreislaufs 10 the battery, powertrain and airflow 70 are temperature-controlled as needed.

For this purpose, the tempering circuit comprises 10 , which can be flowed through by a medium, in particular by a working medium, a compressor 12 , one in the flow direction of the medium downstream of the compressor 12 arranged first heat exchanger 14 and a downstream of the first heat exchanger 14 arranged first expansion device 16 , The medium, which in the present case is the refrigerant R744 or carbon dioxide, is by means of the compressor 12 in which it is an electric refrigerant compressor, compressible. By means of the first expansion device 16 the medium is expandable. Downstream of the first expansion device 16 is a turnoff 18 arranged, by means of which the medium can be divided into partial streams. In the turnoff 18 in leads from the compressor 12 a first line 20 , From the junction 18 lead out a first branch line 22 , a second branch line 24 , a third branch line 26 and a fourth branch line 28 , By means of the branch 18 is this the first line? 20 flowing medium into a first branch line 22 flowing through the first partial flow 30 , in a second branch line 24 flowing through the second partial flow 32 , in a third branch line 26 flowing through third partial stream 34 and in a the fourth branch line 28 flowing through fourth partial flow 36 divisible. An expansion device marked with a cross in the figures is to be understood as a closed expansion device through which the medium does not flow.

In the first branch line 22 are a second heat exchanger 38 and a second expansion device 40 connected in series. Parallel to the first branch line 22 runs the second branch line 24 in which a third heat exchanger 42 and a third expansion device 44 are connected in series. In the third branch line 26 , which are parallel to the first branch line 22 and to the second branch line 24 is switched, are a fifth heat exchanger 46 and a fourth expansion device 48 connected in series. In the present case are the second heat exchanger 38 , the third heat exchanger 42 and the fifth heat exchanger 46 upstream of the respective associated second expansion device 40 , third expansion device 44 and fourth expansion device 48 arranged. The first partial flow 30 , the second partial flow 32 and the third sub-stream 34 of the medium are in a downstream of the second expansion device 40 , the third expansion device 44 and the fourth expansion device 48 arranged collecting device 50 into which the first branch line 22 , the second branch line 24 and the third branch line 26 lead to a common first medium flow 52 compatible. This first medium stream 52 flows in a second line 54 from the collection facility 50 to the compressor 12 ,

At the fourth branch line 28 it is a bypass or a bypass line, by means of which the medium after flowing through the first expansion device 16 at the second heat exchanger 38 , the third heat exchanger 42 and the fifth heat exchanger 46 past the compressor 12 can be fed.

In the second line 54 is downstream of the collector 50 a first portion of a sixth heat exchanger 56 arranged, by means of which heat between the first medium flow 52 and a second medium stream 58 , which will be discussed later, is interchangeable. Downstream of the first portion of the sixth heat exchanger 56 is a fourth heat exchanger in the flow direction of the medium 60 arranged. This fourth heat exchanger 60 in the present case comprises two heat exchanger elements 62 by means of which heat from its environment is transferable to the medium. Downstream of the fourth heat exchanger 60 may in an alternative, not shown embodiment, a connection of the second line 54 to the first line 20 downstream of the compressor 12 consist. In this connection, a fifth expansion device, not shown, may be arranged.

Downstream of the fourth heat exchanger 60 is in the second line 54 a three-way valve 64 arranged, by means of which the fourth partial flow 36 of the medium, which is the fourth branch line 28 flows through, with the second medium flow 58 is compatible. This is what the three-way valve represents 64 a connection between the second line 54 and the fourth branch line 28 ago. The second medium flow 58 in the present case flows in the second line 54 downstream of the fourth heat exchanger 60 and upstream of the compressor 12 ,

Downstream of the three-way valve 64 is in the second line 54 a separator 66 arranged, by means of which the medium is separable into its liquid phase and into its gas phase. Furthermore, downstream of the separator 66 a second portion of the sixth heat exchanger 56 from the second medium stream 58 permeable, so that heat between the first medium flow 52 and the second medium stream 58 is interchangeable. Downstream of the sixth heat exchanger 56 is in the flow direction of the second medium flow 58 the compressor 12 arranged, by means of which the second medium flow 58 compactable and the first line 20 can be fed.

By means of the medium can through the third heat exchanger 42 Heat between the Temperierungskreislauf 10 and a battery circuit, not shown, for the temperature control of a battery of the motor vehicle to be replaced. By means of the fifth heat exchanger 46 can heat from an external heat exchanger 68 be absorbed from the drive train. As a result, the drive train can be cooled and via the fifth heat exchanger 46 Heat in the Temperierungskreislauf 10 be coupled. By means of the first heat exchanger 14 and the second heat exchanger 38 is the airflow 70 dehumidifying and heatable. For dehumidifying the air flow 70 in the flow direction of the air flow 70 only by means of the second heat exchanger 38 cooled and in the flow direction of the air flow 70 downstream of the second heat exchanger 38 by means of the first heat exchanger 14 heated. This airflow 70 is supplied to a vehicle interior of the motor vehicle. In the flow direction of the air flow 70 downstream of the first heat exchanger 14 an unillustrated electrical heat conductor (PTC) can be arranged, by means of which the air flow 70 is further heated.

At the in 1 shown first operating state, the medium by means of the compressor 12 condenses, flows through the first line 20 and then the first heat exchanger 14 , In the first heat exchanger 14 the medium gives heat to the airflow 70 from. Downstream of the first heat exchanger 14 the medium becomes in the first expansion device 16 from his through the compressor 12 relaxed high pressure level to a medium pressure level and then in the branch 18 in the first sub-stream 30 and the second partial flow 32 divided up. The first partial flow 30 flows through the first branch line 22 and the second heat exchanger disposed therein 38 , where the first partial flow 30 Heat from the airflow 70 absorbs and warms up. Subsequently, the first partial flow 30 in the second expansion device 40 from the medium pressure level to a low pressure level and the accumulator 50 fed.

The second partial flow 32 flows through the second branch line 24 and the third heat exchanger disposed therein 42 , This takes the second partial flow 32 Heat from the battery circuit and thus cools the battery circuit and consequently the battery of the motor vehicle. Subsequently, the second partial flow 32 in the third expansion device 44 relaxed from its medium pressure level to the low pressure level and also the collecting device 50 fed, in which the first partial flow 30 and the second part stream 32 to the first medium stream 52 be united. In the flow direction flows through the first medium flow 52 the first part of the sixth heat exchanger 56 and then the fourth heat exchanger 60 , In the fourth heat exchanger 60 The medium can heat from an environment of the fourth heat exchanger 60 as a function of a medium temperature of the medium and in dependence on an ambient temperature of the surroundings of the fourth heat exchanger 60 take up. In the present case, the medium in the first operating state takes heat from an environment of the motor vehicle by means of the fourth heat exchanger 60 on. By means of this described first operating state of the air flow 70 be dehumidified and heated, and the battery of the motor vehicle to be cooled in parallel by means of the medium.

In 2 a schematic pressure-enthalpy diagram is shown with a state circuit of the medium, which different states of the medium when passing through the Temperierungskreislaufs 10 in the first operating state of the Temperierungskreislaufs 10 shows. At a point A in the pressure-enthalpy diagram in 2 the state of the medium is on the dew line, which means that the medium in this point is a saturated vapor. This state, the medium upstream of the compressor 12 on. Downstream of the compressor 12 the medium has the condition in point B as superheated steam. The medium passes through the compressor 12 a polytropic compaction. When flowing through the first heat exchanger 14 the medium is isobaric cooled and then has the state in point C. After an isenthalpic relaxation by means of the first expansion device 16 the medium has the state in point D. When flowing through the second heat exchanger 38 and the third heat exchanger 42 the medium in the respective branch lines is isobarically evaporated, so that it is downstream of the second heat exchanger 38 and downstream of the third heat exchanger 42 has the state in point E. In the second expansion device 40 and the third expansion device 44 the medium is from the state in point E to the state at point F isenthalp relaxed and then in the fourth heat exchanger 60 Isobar evaporates until the medium is upstream of the compressor 12 again has the state in point A.

In a flowchart in 3 shown second operating state of the Temperierungskreislaufs 10 is the medium from the compressor 12 compressed, in the first heat exchanger 14 cooled, in the first expansion device 16 not relaxed, so that the medium upstream of the first expansion device 16 at least substantially the same pressure level as downstream of the first expansion device 16 and then the branch 18 fed. The entire medium is considered the second substream 32 through the second branch line 24 guided and in the third heat exchanger 42 cooled with heat to the battery circuit.

Subsequently, the medium in the third expansion device 44 relaxed and over the second line 54 the first portion of the sixth heat exchanger 56 and the fourth heat exchanger 60 fed. In the fourth heat exchanger 60 will heat out the environment of the heat exchanger 60 transferred to the medium. For closing the temperature control circuit 10 the medium is then passed through the three-way valve 64 , through the separator 66 and through the second portion of the sixth heat exchanger 56 back to the compressor 12 fed. In this second operating state, the battery of the motor vehicle can be particularly advantageous due to the heat emission of the medium in the third heat exchanger 42 to be heated.

An associated state cycle of the medium in the second operating state is in 4 shown in the pressure-enthalpy diagram. Analogous to the first operating state, the medium by means of the compressor 12 Polytropically compressed, so this from the state in point A in the state in point B in 4 is transferred. Subsequently, the medium by means of the first heat exchanger 14 and by means of the series-connected third heat exchanger 42 isobar cooled until the medium in the state in point C having. By means of the third expansion device 44 the medium becomes in point from the state C on the state in point D isenthalp relaxes. An isobaric evaporation of the medium from the state to point D to the state in point A takes place by means of the fourth heat exchanger 60 ,

The flow diagram of the temperature control circuit 10 in 5 shows this in a third operating state, in which the medium after its compression by the compressor 12 in the first heat exchanger 14 under heat to the airflow 70 is cooled, by means of the first expansion device 16 is relaxed from its high pressure level to the intermediate pressure level and in the diversion 18 in the first sub-stream 30 and the third sub-stream 34 is split. By means of the first partial flow 30 becomes the airflow 70 in the first heat exchanger 38 cooled, resulting in the first partial flow 30 heated. Subsequently, the first partial flow 30 the second expansion device 40 fed to the relaxation of the medium pressure level to the low pressure level and then flows into the collector 50 , The third partial flow 34 flows through the heat absorption the fifth heat exchanger 46 , being over the external heat exchanger 68 Heat is removed from the drive train of the motor vehicle and this is therefore cooled. The third partial flow 34 of the medium then flows through the fourth expansion device 48 , It is relaxed from the medium pressure level to the low pressure level and then the collector 50 fed, in which the first partial flow 30 and the third sub-stream 34 to the first medium stream 52 be united. In this third operating state, therefore, the air flow 70 dehumidified and then reheated and at the same time the drive train of the motor vehicle via the external heat exchanger 68 be cooled.

In 6 is the tempering circuit 10 represented in the flowchart in a fourth operating state. In this fourth operating state, the medium after its compression by means of the compressor 12 in the first heat exchanger 14 under heat to the airflow 70 cooled, and then in the first expansion device 16 relaxed from the high pressure level to the medium pressure level. In the turnoff 18 the medium is completely the second branch 24 as a second partial flow 32 fed, takes place when flowing through the third heat exchanger 42 Heat from the battery circuit to cool the battery and then in the third expansion device 44 expanded to low pressure. Subsequently, the medium flows through the fourth heat exchanger 60 in which the medium heat from the environment of the heat exchanger 60 can record. In connection with 6 described fourth operating state of the Temperierungskreislaufs 10 can the airflow 70 be heated while the battery is above the battery circuit and the third heat exchanger 42 is cooled. In the present case is a dehumidification of the air flow 70 by cooling by means of the second heat exchanger 38 not necessary in the fourth operating state.

The in connection with the 1 to 6 described invention relates to a concept for air conditioning of the motor vehicle, in particular a motor vehicle, in particular a passenger car with a carbon dioxide heat pump. Carbon dioxide is a refrigerant designated R744. The air conditioning of the passenger car by means of this carbon dioxide heat pump is energetically advantageous, in particular in electrically operable motor vehicles, since these have a high efficiency, in particular a coefficient of performance (COP) of more than 2. Advantageously, by means of the in connection with the 1 to 6 described Temperierungskreislaufs 10 an efficiency especially in a winter operation are kept particularly high. In this way, a short range of the electrically operable motor vehicle at extreme outside temperatures can be avoided and a particularly high Well to Wheel efficiency can be achieved. In this way, a particularly high overall efficiency of the motor vehicle can be achieved, in particular of the powertrain and the traction battery. This particularly high efficiency can be achieved by the intelligent interconnection of the components described by means of the FIGURE and by the integration of a multi-evaporator system, with which in particular a series connection of the plurality of expansion devices of the temperature-control circuit 10 to be understood, to be achieved. In addition, a complexity of Temperierungskreislaufs 10 As well as a number of components required for integration of heat loss of the motor vehicle in existing production concepts are kept particularly low. Main advantage of the Temperierungskreislaufs 10 is the ability to operate in a heat pump mode, in this case the second operating state, in which a passenger compartment of the motor vehicle via the air flow 70 and the battery circuit can be heated with a particularly high performance and efficiency. In summer, the battery can be cooled as described in connection with the fourth operating state and heated in winter according to the second operating state.

Through the described Temperierungskreislauf 10 allows a physically necessary temperature control of the battery while maintaining the thermal comfort of the means of the air flow 70 air-conditioned passenger compartment should be designed in the most efficient way possible. Previous concepts provide for heating the battery circuit only an electric heat conductor (PTC), which is operated via an electrical system of the motor vehicle. By operation of the Temperierungskreislaufs 10 In the second operating state, which is the heat pump mode, heating of the battery can be designed much more efficiently than with the electric heat conductor, since the temperature control circuit 10 works with a higher efficiency than the electrical heat conductor. This is especially useful for a Well to Wheel view. By the heat transfer from the external heat exchanger 68 on the fifth heat exchanger 46 a loss energy of a Temperierungskreislaufs, which is filled with a water-glycol mixture, the drive train used to provide a particularly high level of comfort for a user as efficiently as possible by the heat in the Temperierungskreislauf 10 is integrated and via the first heat exchanger 14 to the airflow 70 is delivered. As a result, a proportion of load cases can be kept particularly high in a recirculation mode. In the first operating state leaves through a flow through the fourth heat exchanger 60 from the first medium stream 52 achieve a particularly high Enthalpiespreizung, which in particularly high performance figures of Temperierungskreislaufs 10 results. In particular, at a vehicle start of the motor vehicle after a long period of lactation at very low temperatures, the passenger compartment of the motor vehicle should be preconditioned by the air flow 70 by means of the first heat exchanger 14 is heated in the second mode of operation and when flowing through the second heat exchanger 38 no heat over the second heat exchanger 38 to the medium. In the second operating state can by the flow through the medium through the first heat exchanger 14 and the third heat exchanger 42 In series, a particularly high enthalpy spread can be achieved, whereby a particularly high power in the form of heat can be delivered to the battery circuit. Subsequently, by means of the medium via the fourth heat exchanger 60 , which may be arranged on a front end of the motor vehicle, heat absorbed. For a particularly high power supply for the heating of the battery, in this case the traction battery, can via the external heat exchanger 68 and the fifth heat exchanger 46 Heat from the drive train of the motor vehicle in the Temperierungskreislauf 10 be absorbed and over the third heat exchanger 42 be transferred to the battery circuit for heating the battery at a later time.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 2013/0025311 A1 [0002]
• DE 10253357 A1 [0005]

Claims (10)

Tempering circuit (10) for a motor vehicle, which is flowed through by a medium, with a compressor (12), with a downstream of the compressor (12) arranged first heat exchanger (14), by means of which an air flow (70) for a vehicle interior of the motor vehicle heated is, with a second heat exchanger (38) arranged downstream of the first heat exchanger (14) for cooling the air flow (70), with a third heat exchanger (42) arranged downstream of the first heat exchanger (14) for tempering a battery of the motor vehicle, with at least one downstream of the second heat exchanger (42) arranged fourth heat exchanger (60), by means of which heat from its environment is transferable to the medium, with a between the first heat exchanger (14) and the second heat exchanger (38) arranged first expansion means (16) a second expansion disposed between the second heat exchanger (38) and the fourth heat exchanger (60) Device (40), and with a downstream of the third heat exchanger (42) arranged third expansion means (44), characterized in that the second heat exchanger (38) and the third heat exchanger (42) and the second expansion device (40) and the third expansion device (44) downstream of the first heat exchanger (14) and upstream of the fourth heat exchanger (60) are each connected in parallel to each other. Temperierungskreislauf (10) after Claim 1 , characterized in that a fifth heat exchanger (46), by means of which heat from a drive train of the motor vehicle is transferable to the medium, and a downstream of the fifth heat exchanger (46) arranged fourth expansion means (48) are provided, which downstream of the first heat exchanger ( 14) and upstream of the fourth heat exchanger (60) are connected in parallel with the second heat exchanger (38), the third heat exchanger (42), the second expansion means (40) and the third expansion means (44). Temperierungskreislauf (10) after Claim 1 or 2 , characterized in that a sixth heat exchanger (56) is provided which can be flowed through by a first medium flow (52) of the medium flowing towards the fourth heat exchanger (60) and by a second medium flow (58) of the medium flowing towards the compressor (12) , wherein via the sixth heat exchanger (56) heat between the medium streams is interchangeable. Tempering circuit (10) according to any one of the preceding claims, characterized in that downstream of the fourth heat exchanger (60) and upstream of the compressor (12) is arranged a separator (66) for separating the medium into its liquid phase and into its gas phase. Tempering circuit (10) according to any one of the preceding claims, characterized in that a bypass (28) is provided, by means of which the medium after flowing through the first expansion means (16) on the second heat exchanger (38), the third heat exchanger (42) fourth heat exchanger (60) and the fifth heat exchanger (46) past the compressor (12) can be fed. Tempering circuit (10) according to any one of the preceding claims, characterized in that the medium is formed as carbon dioxide. Method for operating a temperature control circuit (10) for a motor vehicle, in which a medium flows through the temperature control circuit (10) and thereby: - is compressed by means of a compressor (12); - flows through a downstream of the compressor (12) arranged first heat exchanger (14) through which for heating an air flow (70) for a vehicle interior of the motor vehicle heat from the medium to the air flow (70) passes; - flows through a downstream of the first heat exchanger (14) arranged second heat exchanger (38), by means of which for the cooling of the air flow (70) heat from the air stream (70) passes to the medium; - flows through a downstream of the first heat exchanger (14) arranged third heat exchanger (42), via which a battery of the motor vehicle is tempered by means of the medium; - Traversed downstream of the second heat exchanger (38) arranged fourth heat exchanger (60) through which heat is transferred from its environment to the medium; - A between the first heat exchanger (14) and the second heat exchanger (38) arranged first expansion means (16) flows, by means of which the medium is expanded; - A between the second heat exchanger (38) and the fourth heat exchanger (60) arranged second expansion means (40) flows, by means of which the medium is expanded; and - a third expansion means (44) arranged downstream of the third heat exchanger (42) flows through which the medium is expanded; characterized in that the second heat exchanger (38) and the third Heat exchanger (42) and the second expansion device (40) and the third expansion device (44) downstream of the first heat exchanger (14) and upstream of the fourth heat exchanger (60) are each connected in parallel to each other, so that the medium in each case parallel to the second heat exchanger (38) and the third heat exchanger (42) and the second expansion device (40) and the third expansion device (44) flows through. Method according to Claim 7 , characterized in that a fifth heat exchanger (46), by means of which heat from a drive train of the motor vehicle is transferred to the medium, and a downstream of the fifth heat exchanger (46) arranged fourth expansion means (48) are provided, by means of which the medium is expanded wherein the fifth heat exchanger (46) and the fourth expansion device (48) downstream of the first heat exchanger (14) and upstream of the fourth heat exchanger (60) parallel to the second heat exchanger (38), the third heat exchanger (42), the second expansion device ( 40) and the third expansion means (44) are connected. Method according to Claim 7 or 8th , characterized in that the medium flows through the first heat exchanger (14), the third heat exchanger (42) with heat release to the battery of the motor vehicle. Motor vehicle with a Temperierungskreislauf (10) according to one of Claims 1 to 6 , which is adapted to a method according to one of Claims 7 to 9 perform.

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