Heat treatment systems for vehicles

Abstract

The invention relates to a vehicle thermal management system (1), comprising at least a refrigerant circuit (2), a circuit for a heat transfer liquid (3) and a first heat exchanger (5), the first heat exchanger thermally coupling the circuit for the heat transfer liquid (3) to the refrigerant circuit (2), the circuit for the heat transfer liquid (3) comprising at least one heat exchanger (12, 35) configured to dissipate heat energy into an air flow (18, 19), the refrigerant circuit (2) comprising at least a compression device (4), the first heat exchanger (5), a refrigerant accumulation device (6), a first expansion device (16) and a second heat exchanger (17), the second heat exchanger being designed to allow an internal air flow (18) to pass through the vehicle compartment interior, characterized in that the refrigerant circuit (2) comprises a branch (20) arranged in parallel with the first expansion device (16) and the second heat exchanger (17), the branch (20) comprising a second expansion device (21) and a third heat exchanger (22) capable of being thermally coupled to at least one component of the vehicle's electric drive train.

Description

Technical Field

[0001] The field of the invention is thermal management systems for heating or cooling spaces or components of vehicles, in particular motor vehicles. Background Art

[0002] Currently, motor vehicles are equipped with a refrigerant circuit for heating or cooling various areas or components of the vehicle. From document FR3055250A1 it is known in particular that this refrigerant circuit is used for thermal treatment of an air flow fed into the cabin of a vehicle equipped with such a circuit.

[0003] In another application of this circuit, it is known to be used to cool an electric storage device of a vehicle, said device being used to provide energy to an electric motor capable of moving the vehicle. Thus, when the refrigerant circuit is used during the driving phase, the refrigerant circuit provides energy capable of cooling the electric storage device.

[0004] It is particularly complex to combine the functions of cooling the interior of the vehicle and cooling the electric storage device of the vehicle in one and the same refrigerant circuit. Such an architecture requires many components and is therefore complex. The structure in particular includes many valves and generally exceeds the capacity that can be expected for its basic function. This is a major disadvantage of the known system.

[0005] Furthermore, the above-described refrigerant circuit uses an accumulator located immediately upstream of the compression device. This component is particularly bulky, which makes its installation on the vehicle more complicated and is detrimental to the cost of the refrigerant circuit. Furthermore, the use of an accumulator prevents achieving a performance compromise between the three operating modes covered by the invention: a first mode for cooling the interior of the vehicle, a second mode for cooling a component of the electric powertrain, and a third mode in which thermal energy is recovered from at least one component of the electric powertrain. The use of an accumulator thus constitutes a second disadvantage. Summary of the invention

[0006] The present invention falls into this context and proposes a technical solution which includes a limited number of components and restricted circuit wiring, and in which the volume and manufacturing cost after installation in the vehicle are controlled, while providing the option of performing at least three functions, including the function of cooling the interior of the vehicle, the function of recovering energy from components in the vehicle's electric powertrain, and the function of thermal management of components in the vehicle's electric powertrain.

[0007] Therefore, the subject of the present invention is a vehicle thermal management system, comprising at least a refrigerant circuit, a loop for a heat transfer liquid and a first heat exchanger, the first heat exchanger thermally connecting the loop for the heat transfer liquid to the refrigerant circuit, the loop for the heat transfer liquid comprising at least one heat exchanger configured to dissipate heat energy into an air flow, the refrigerant circuit comprising at least a compression device, a first heat exchanger, a refrigerant accumulation device, a first expansion device and a second heat exchanger, the second heat exchanger being designed to allow an internal air flow delivered into a vehicle cabin to pass through, the innovation being that the refrigerant circuit comprises a branch arranged in parallel with the first expansion device and the second heat exchanger, the branch comprising a third heat exchanger and a second expansion device capable of being thermally connected to components of the vehicle's electric drive system.

[0008] According to one aspect, the refrigerant circuit comprises a first part and a second part, the first part comprising at least a compression device, a first heat exchanger, a refrigerant accumulator, the second part comprising a first expansion device and a second heat exchanger, the second heat exchanger being designed to pass through an interior air flow introduced into a vehicle cabin. From the refrigerant point of view, the branch comprising the second expansion device and the third heat exchanger is parallel to the second part.

[0009] The third heat exchanger is in particular thermally coupled to one of the components of the electric drive train of the vehicle, for example to an electric motor propelling the vehicle, to an electrical storage device or to a power electronics module controlling the electric motor mentioned here.

[0010] The refrigerant is for example a subcritical fluid, as known with reference to R134A or R1234yf.The refrigerant circuit according to the invention is a closed circuit which executes a thermodynamic cycle, in particular involving the thermodynamic circulation of compressed vapor.

[0011] The compression device is, for example, a compressor, and the invention is particularly applicable when the compressor is a variable speed electric compressor of fixed cylinder capacity. Thus, the thermal power of the refrigerant circuit can be controlled.

[0012] The first heat exchanger forms a zone for heat exchange between the refrigerant and the heat transfer liquid. This is an exchanger comprising a first compartment through which the refrigerant passes and a second compartment used by the heat transfer liquid, the two compartments being organized so that thermal energy is transferred therein.

[0013] The accumulator device is advantageously a bottle, in particular a desiccant bottle.Depending on the flow direction of the refrigerant, the accumulator device can be integrated into the first heat exchanger or positioned directly downstream of the first heat exchanger.

[0014] Advantageously, the elements of the refrigerant circuit can be positioned one after the other in a precise sequence. It is noteworthy that, depending on the envisaged operating mode, this arrangement makes it possible to achieve first-class thermal performance at low cost.

[0015] Advantageously, the refrigerant circuit comprises a branch point where the branch begins and a junction point where the branch ends, the refrigerant circuit comprises an internal heat exchanger comprising a first channel and a second channel, the first channel and the second channel being configured to allow the refrigerant to pass through them, the second channel of the internal heat exchanger being located between the junction point and the inlet of the compression device. Thus, the refrigerant circuit is equipped with an internal heat exchanger that is common to the refrigerant circulating in the second portion and the refrigerant circulating in the branch.

[0016] Alternatively, the refrigerant circuit includes a branch point where the branch starts and a junction point where the branch ends, and the refrigerant circuit includes a first internal heat exchanger, at least one channel of the first internal heat exchanger is located between the outlet of the second heat exchanger and the junction point. In this case, the first internal heat exchanger acts only on the refrigerant delivered to the second heat exchanger.

[0017] Alternatively or additionally, the refrigerant circuit comprises a second internal heat exchanger, at least one channel of which is located between the outlet and the junction of the third heat exchanger. In this case, the second internal heat exchanger acts only on the refrigerant delivered to the third heat exchanger.

[0018] In one example, the first expansion device and / or the second expansion device are configured to cut off any flow of refrigerant towards the second heat exchanger or towards the third heat exchanger, respectively.

[0019] It should be noted that the first expansion device and / or the second expansion device may be a thermostatic expansion valve.

[0020] Alternatively, the first expansion device and / or the second expansion device is an electronically controlled expansion valve.

[0021] In one embodiment, the refrigerant circuit comprises a fourth heat exchanger designed to be traversed by the flow of external air of the vehicle cabin and positioned between the outlet of the accumulator device and the branching point.

[0022] The fourth heat exchanger may be used in particular for subcooling the refrigerant.The positioning of the fourth heat exchanger in the refrigerant circuit according to the invention makes it possible in particular to minimize the number of valves and pipes required to incorporate the subcooling exchanger.

[0023] Advantageously, the fourth heat exchanger is upstream of the heat exchangers according to the circulation direction of the air flow passing through them.

[0024] According to an optional aspect of the present invention, the refrigerant circuit includes at least one check valve located between the outlet of the fourth heat exchanger and the branch point.

[0025] Advantageously, the refrigerant circuit comprises at least one first control valve which controls the circulation of the refrigerant towards the fourth heat exchanger.

[0026] Still advantageously, the refrigerant circuit comprises at least one conduit connecting the outlet of the accumulator to the branching point, said conduit being arranged in parallel with the first portion of the refrigerant circuit.

[0027] In this configuration, the refrigerant circuit may include a second control valve that controls the flow of the refrigerant in the pipeline.

[0028] As an alternative to the first valve and the second valve, the refrigerant circuit comprises at least one three-way valve, which is located at a separation point separating the circuit.

[0029] According to one aspect of the invention, the heat exchanger for the circuit of heat transfer liquid is a radiator designed to be traversed by the external air flow of the vehicle cabin.

[0030] Alternatively, the heat exchanger for the circuit of heat transfer liquid is a unit heater designed to be traversed by the flow of interior air delivered into the vehicle cabin.

[0031] Of course, the invention covers a combination of these means, wherein the circuit for the heat transfer liquid comprises a first heat exchanger designed to be traversed by an air flow outside the vehicle cabin and a second heat exchanger designed to be traversed by an internal air flow delivered into the vehicle cabin. In this case, the first heat exchanger is a radiator and the second heat exchanger is a unit heater. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Other features, details and advantages of the invention will become more apparent from reading the following description provided by way of illustration and with reference to the accompanying drawings, in which:

[0033] Figure 1 is a schematic diagram of a thermal management system according to the present invention in a first embodiment;

[0034] Figure 2 is a schematic diagram of a thermal management system in a second embodiment;

[0035] Figure 3 is a schematic diagram of a thermal management system in a third embodiment;

[0036] Figures 4 to 6 Shows the application Figure 1 , 2 or a variation of the thermal management system of 3;

[0037] Figures 7 to 10 shows the operation according to various operation modes, forming Figure 3 The subject of thermal management systems. DETAILED DESCRIPTION

[0038] It should be noted at the outset that the accompanying drawings illustrate in detail the invention for implementing the invention, although, if necessary, said drawings may be used to better define the invention. These figures are schematic diagrams that illustrate the way in which a thermal management system is produced, its composition and the way in which fluids circulate therein. In particular, the thermal management system comprises, on the one hand, a refrigerant circuit and a circuit for a heat transfer liquid and a heat exchanger traversed by these two fluids.

[0039] The refrigerant circuit mainly consists of a device for compressing the refrigerant, a heat exchanger, an expansion device, pipes connecting each of these components, and valves or shutters. The circuit may also be placed under the control of a controller that acts on some of its components.

[0040] The terms upstream and downstream used in the following description refer to the flow direction of the fluid in question, ie the refrigerant, the heat transfer liquid, the interior air flow to the vehicle cabin or the exterior air flow to the vehicle cabin.

[0041] exist Figures 7 to 10 In the diagram, the refrigerant is represented by arrows showing the direction of flow of the refrigerant in the pipe in question. A solid line shows a portion of a circuit in which the refrigerant flows, while a dashed line shows no flow of the refrigerant. A thick line shows the refrigerant at a high pressure and temperature, while a thin line shows the refrigerant at a low pressure and temperature.

[0042] therefore, Figure 1 A thermal management system 1 is shown, comprising a refrigerant circuit 2, in which a refrigerant circulates, and a loop 3 for a heat transfer liquid, in which the heat transfer liquid moves.

[0043] The refrigerant circuit 2 is a closed loop in which the refrigerant circulates through a compression device 4. It should be noted that the compression device 4 can be in the form of an electric compressor, that is, a compressor comprising a compression mechanism, an electric motor and possibly a controller. The rotating mechanism is rotated by the electric motor, and the rotation speed of the electric motor is controlled by the controller, which can be outside or inside the compression device.

[0044] according to Figure 1In the first embodiment shown, the refrigerant circuit 2 comprises, in this order and according to the direction in which the refrigerant circulates therein, at least a compression device 4 connected by a pipe to a first heat exchanger 5 which thermally couples the circuit 3 for the heat transfer liquid to the refrigerant circuit 2. This first heat exchanger 5 is connected by a pipe to a refrigerant accumulation device 6. Thus, in this example, this accumulation device 6 is, for example, positioned immediately downstream of the first heat exchanger 5 and can, for example, take the form of a desiccant bottle. Figure 5 It can be seen from the description that the position of the storage device 6 can be changed without departing from the scope of the present invention.

[0045] The above-mentioned elements of the refrigerant circuit 2 form part of a first portion 14 of the refrigerant circuit 2. The first portion 14 starts at a branching point 29 of the refrigerant circuit 2 and ends at a junction 32.

[0046] The refrigerant circuit 2 also comprises a second portion 15 extending from the branching point 29 to the junction point 32, thereby closing the circuit relative to the first portion 14. The second portion 15 comprises at least a first expansion device 16 and a second heat exchanger 17, which is designed to be passed through by an internal air flow 18 delivered to the vehicle cabin. The second portion 15 may also comprise an internal heat exchanger.

[0047] The accumulator 6 is then directly connected to the internal heat exchanger 26, in particular to a first channel 27 of this internal heat exchanger 26. This first channel 27 of the internal heat exchanger 26 is directly connected to a branch point 29, ie a point where the refrigerant can be divided into two parts.

[0048] The refrigerant circuit 2 also comprises a first expansion device 16 interposed between the branching point 29 and a second heat exchanger 17 designed to be traversed by the flow of interior air delivered into the vehicle cabin.

[0049] According to this embodiment, the first expansion device 16 is an electronically controlled expansion valve comprising at least a total shutoff function which prevents the circulation of the refrigerant through it. Thus, the first expansion device 16 according to the invention is configured to adopt at least a position in which it prevents any circulation of the refrigerant to the second heat exchanger 17, and a position in which it produces a pressure head drop in the refrigerant, in particular in order to cause its expansion. It should be noted that this second heat exchanger 17 acts as an evaporator to cool the internal air flow 18 sent into the interior of the vehicle cabin.

[0050] One outlet of the second heat exchanger 17 is connected to a junction 32, i.e. the point through which the two refrigerant flows meet to combine into a single flow that is directed towards the internal heat exchanger 26. The latter thus comprises a second channel 30 connected on one side to the junction 32 and on the other side to the inlet of the compression device 4, where the thermodynamic cycle can be restarted. Thus, the refrigerant circulating in the first channel 27 of the internal heat exchanger 26 exchanges thermal energy with the refrigerant circulating in the second channel 30 of the same internal heat exchanger.

[0051] According to the invention, the refrigerant circuit 2 comprises a circuit branch 20 mounted in parallel with the second portion 15. This branch 20 is therefore connected to a branching point 29 and a junction point 32.

[0052] It will be understood that the internal heat exchanger 26 is common to the second portion 15 of the refrigerant circuit 2 comprising the first expansion device 16 and the second heat exchanger 17 and to the branch 20 of the circuit comprising the second expansion device 21 and the third heat exchanger 22. This internal heat exchanger 26 is common as long as the refrigerant passing through the first channel 27 of the secondary internal heat exchanger 26 is divided into two flows, each of which supplies the second portion 15 and the branch 20, this division taking place after the first channel 27, at the second branching point 29.

[0053] The refrigerant circuit branch 20 comprises a second expansion device 21 and a third heat exchanger 22, the third heat exchanger 22 being designed to cool the additional fluid 9. The second expansion device 21 is in particular an electrically controlled expansion valve, which comprises at least a total shut-off function which prevents the refrigerant from circulating through it. Therefore, the second expansion device 21 according to the invention is configured to adopt at least a position in which it prevents any circulation of the refrigerant to the third heat exchanger 22, and a position in which it produces a head drop in the refrigerant towards the third heat exchanger 22, in particular in order to cause the refrigerant to expand. It should be noted that the third heat exchanger 22 acts as an evaporator to cool an additional fluid thermally coupled to at least one component of the electric powertrain of the vehicle, for example, such a component may be an electric motor providing the vehicle's propulsion, an electric energy storage device or an electronic control module controlling the electric motor. The third heat exchanger 22 is a heat exchanger that exchanges heat between the refrigerant and the additional fluid 9, in particular glycol water, and makes it possible to cool components of the powertrain, or to collect thermal energy from the electric powertrain to use it beneficially in the thermodynamic cycle occurring in the refrigerant circuit 2.

[0054] The circuit 3 for heat transfer liquid comprises for its part at least a first heat exchanger 5 connected by pipes to at least one heat exchanger 12 configured to emit thermal energy into an air flow. The circuit 3 for heat transfer liquid also comprises at least one pump 13 which displaces the heat transfer liquid in such a way that it circulates through the first heat exchanger 5 and the heat exchanger 12.

[0055] The first heat exchanger 5 is a heat exchanger for exchanging heat between a refrigerant and a heat transfer liquid, wherein a transfer of thermal energy can take place between one of these fluids and the other.

[0056] In this example, the circuit 3 for the heat transfer liquid here comprises two heat exchangers configured to emit thermal energy into the air flow, each heat exchanger being arranged in a circuit section that is different from one another and extends parallel to one another, in particular a first section and a second section of the circuit for the heat transfer liquid. Thus, the first heat exchanger 12 is traversed by the heat transfer liquid and the internal air flow 18 fed into the interior of the vehicle cabin. This first heat exchanger 12 is a unit heater whose task is to heat the interior of the vehicle cabin in cold conditions.

[0057] The circuit 3 for the heat transfer liquid comprises a circuit portion in which a second heat exchanger 35 is present, which is configured to dissipate heat energy into the external air flow 19 of the vehicle compartment. In other words, this second heat exchanger 35 is placed on the front face of the vehicle. The function of the second heat exchanger 35 is to discharge the heat energy originating from the first heat exchanger 5 and transported by the heat transfer liquid into the external air flow 19. In this respect, the second heat exchanger 35 is a radiator.

[0058] The portion of the loop 3 for the heat transfer liquid including the second heat exchanger 35 also includes a circulation device 48 for circulating the heat transfer liquid in this portion, so that the heat transfer liquid carries the heat energy absorbed in the first heat exchanger 5 as far as the second heat exchanger 35 in order to discharge it into the external air flow 19.

[0059] Figure 2 A second embodiment of a thermal management system 1 forming the subject of the present invention is shown. In addition to the elements described in detail below, the refrigerant circuit 2 is connected to Figure 1 The refrigerant circuit described in Figure 1 description, which applies mutatis mutandis to Figure 2 .

[0060] In this second embodiment, the common internal heat exchanger is replaced by separate internal heat exchangers, wherein the first internal heat exchanger is installed in the second portion 15 of the circuit, while the second internal heat exchanger is placed in the branch 20 parallel to the second portion 15 of the refrigerant circuit 2. Thus, the second portion 15 comprises a first internal heat exchanger 36, while the branch 20 comprises a second internal heat exchanger 37 separate and distinct from the first internal heat exchanger 36.

[0061] Thus, the first internal heat exchanger 36 includes a first passage 38 arranged in a path connecting the branch point 29 to the inlet of the first expansion device 16. The first internal heat exchanger 36 also includes a second passage 39 arranged between the outlet of the third heat exchanger 17 and the junction 32. Therefore, it should be understood that the heat exchange that occurs in the first internal heat exchanger 36 is dedicated to the refrigerant supplied to and from the second heat exchanger 17.

[0062] The branch 20 of the circuit comprises a second internal heat exchanger 37 comprising a first channel 40 arranged in a path connecting the branch point 29 to the inlet of the second expansion device 21. The second internal heat exchanger 37 also comprises a second channel 42 arranged between the outlet of the third heat exchanger 22 and the junction 32. It will therefore be appreciated that the heat exchange that takes place in the second internal heat exchanger 37 is dedicated to the refrigerant supplied to and from the third heat exchanger 22.

[0063] Figure 3 A third embodiment of the management system 1 forming the subject of the present invention is shown. This third embodiment is largely similar to the one described with reference to Figure 2 The same as described, which description applies mutatis mutandis to Figure 3 Examples and Figure 2 The differences between the embodiments.

[0064] exist Figure 1 or 2, the outlet of the storage device 6 is connected to the branch point 29 via a pipeline, Figure 3 A refrigerant circuit 2 is shown which comprises a fourth heat exchanger 10 which is designed to be traversed by an external air flow 19 of the vehicle compartment. The fourth heat exchanger 10 is located between the outlet of the accumulator 6 and the branch point 29 on the refrigerant circuit 2. It should be understood here that the fourth heat exchanger 10 is downstream of the first heat exchanger 5 according to the flow direction of the refrigerant.

[0065] The fourth heat exchanger 10 may be used in particular for subcooling the refrigerant.The positioning of the fourth heat exchanger 10 in the refrigerant circuit 2 according to the invention makes it possible in particular to minimize the number of valves and pipes required to incorporate a subcooling exchanger.

[0066] In practice, such a fourth heat exchanger 10 is positioned, for example, on the front face of the vehicle to be exposed to the external air flow 19 generated by the movement of the vehicle. Such an arrangement in the vehicle makes it possible in particular to optimize the dimensions of the fourth heat exchanger 10, in particular in order to exploit the total available surface area on the front face.

[0067] The refrigerant circuit 2 further includes a first control valve 23, which controls the circulation of the refrigerant in the fourth heat exchanger 10. A check valve 34 also controls the circulation of the refrigerant and is located between the outlet of the fourth heat exchanger 10 and the branch point 29. The check valve 34 allows the refrigerant to circulate from the accumulator 6 toward the branch point 29 and prevents any circulation of the refrigerant in the opposite direction, i.e., from the branch point 29 toward the accumulator 6.

[0068] The first main valve 23 is configured to shut off the flow of the refrigerant in the fourth heat exchanger 10 , and is located, for example, between the accumulator 6 and an inlet of the fourth heat exchanger 10 .

[0069] From the perspective of the outside air flow 19 , the fourth heat exchanger 10 is upstream of the first heat exchanger 35 .

[0070] Figure 3 Also shown is a pipe 33 connecting the outlet of the accumulator 6 to a connection point 7 between the branch point 29 and the inlet of the first channel 40 of the second internal heat exchanger 37. The refrigerant circuit 2 comprises a second valve 25 configured to shut off the refrigerant circulation in this pipe 33.

[0071] Figure 4 A variant embodiment is shown which can be converted into the third embodiment described above. The compression device 4 discharges the hot refrigerant into the first heat exchanger 5 .

[0072] When the heat energy of the refrigerant is removed, it cautiously enters the accumulator 6 located between the outlet of the first heat exchanger 5 and the inlet of the fourth heat exchanger.

[0073] The first valve and the second valve are replaced here by a three-way valve 43 whose first port 44 is connected to the outlet of the accumulator 6 , whose second port 45 is connected to the inlet of the fourth heat exchanger 10 , and whose third port 46 is connected to the pipeline 33 .

[0074] Figure 5 It shows that it can be applied to Figure 1 and Figure 2 An alternative embodiment of any one of the embodiments of . In this alternative, the accumulation device 6 is integrated into the first heat exchanger 5.

[0075] Thus, the first heat exchanger 5 comprises at least a first zone 8 dedicated to a phase of condensing the refrigerant and a second zone 11 dedicated to a phase of subcooling the refrigerant. The accumulator 6 is incorporated in the first heat exchanger 5, at the border between these two zones 8, 11. In the case of a desiccant bottle, it receives the refrigerant leaving the first zone 8, accumulates it and delivers it in liquid state to the second zone 11 of the first heat exchanger 5.

[0076] Figure 6 It shows that they can be applied to Figure 1 , 2 3 and 4. In this particular case, Figure 6 A common internal heat exchanger 26 is shown, but it will be understood that the modifications set out herein below can be reapplied to embodiments using first and second internal heat exchangers respectively assigned to the second portion 15 of the circuit and its branches 20 .

[0077] In this variant, the first expansion device 16 and the second expansion device 21 are controlled closing thermostatic expansion valves. In fact, these are thermostatic expansion valves whose input cross section depends on the temperature and / or pressure of the refrigerant at the outlet of the associated heat exchanger. The controlled closing of the thermostatic expansion valves is performed by a shut-off valve 47 built into the thermostatic expansion valves, which is configured to adopt at least a position that prevents any circulation of the refrigerant through the controlled closing thermostatic expansion valves, in particular towards the inlet of the second heat exchanger 17 or the inlet of the third heat exchanger 22.

[0078] Figure 7 By way of example, Figure 3 The third embodiment shown. The figure shows the operating mode corresponding to cooling the air flow 18 introduced into the interior of the vehicle cabin.

[0079] The compression device 4 raises the pressure and temperature of the refrigerant. The hot refrigerant is cooled while passing through the first heat exchanger 5. In this way, the refrigerant condenses and leaves the first heat exchanger 5 in liquid state, which then acts as a condenser. The liquid refrigerant is stored in the accumulator 6, and only its liquid part leaves the accumulator 6 and flows to the fourth heat exchanger 10. This is possible because the first valve 23 is in the open position and the second valve 25 is in the closed position.

[0080] The refrigerant circulates in the fourth heat exchanger 10 in liquid state and undergoes forced subcooling, i.e., its temperature is reduced to below its condensation temperature. This forced subcooling is performed by means of an external air flow 19 passing through the fourth heat exchanger 10. When leaving the fourth heat exchanger 10, the refrigerant passes through a non-return valve 34 and reaches a branch point 29.

[0081] The refrigerant in liquid state enters the first internal heat exchanger 36 through the first passage 38. The refrigerant then reaches the first expansion device 16, in which it undergoes expansion. The refrigerant then evaporates while flowing through the second heat exchanger 17, which is traversed by the internal air flow 18 conveyed into the vehicle cabin. This is how cooling of the interior of the vehicle cabin is achieved.

[0082] Then, the refrigerant in the gaseous state leaves the second heat exchanger 17 and passes through the second passage 39 of the first internal heat exchanger 36. There is a transfer of thermal energy between the liquid refrigerant present in the first passage 38 of the first internal heat exchanger 36 and the gaseous refrigerant present in the second passage 39. The refrigerant leaving the second passage 39 of the first internal heat exchanger 36 eventually reaches the inlet of the compression device 4, so that a new thermodynamic cycle can occur within the refrigerant circuit 2.

[0083] On the branch 20 side of the circuit, the second expansion device 21 is in the closed position, which means that the third heat exchanger 22 is inactive.

[0084] As far as the circuit 3 for the heat transfer liquid is concerned, the pump 13 is turned off, which means that there is no circulation of heat transfer liquid in the first part of the heat transfer liquid circuit between the first heat exchanger 5 and the first heat exchanger 12. On the contrary, the circulation means 48 are active and circulate the heat transfer liquid in the second part of the heat transfer liquid circuit between the first heat exchanger 5 and the second heat exchanger 35, thereby unloading the heat energy to the external air flow 19.

[0085] Figure 8 An operating mode is shown corresponding to cooling of components of the vehicle's electric powertrain by means of an additional fluid 9. Such components are for example electric motors for propelling the vehicle, electrical storage devices or in particular power electronics modules controlling electric motors for propulsion.

[0086] Part I 14 Refrigerant Behavior and Figure 7 The behavior is the same as that of , and can be described with reference to the description of that figure. This mode of operation is the same as Figure 7 The operating mode differs in that the first expansion device 16 is placed in a closed position, thereby preventing any circulation of refrigerant in the second heat exchanger 17 .

[0087] On the other hand the branch 20 is active, the third heat exchanger 22 operating as an evaporator. The refrigerant in liquid state passes through the first channel 40 of the second internal heat exchanger 37 and reaches the second expansion device 21, in which it undergoes expansion. The refrigerant then evaporates as it passes through the third heat exchanger 22, which is traversed by the additional heat transfer liquid 9 which exchanges heat with one or another of the above-mentioned components of the electric drive train. This is how the cooling of the component is caused.

[0088] The gaseous refrigerant then leaves the third heat exchanger 22 and passes through the second channel 42 of the second internal heat exchanger 37. There is a transfer of thermal energy between the liquid refrigerant present in the first internal channel 40 of the second internal heat exchanger 37 and the gaseous refrigerant present in the second channel 42. The refrigerant leaving the second channel 42 of the second internal heat exchanger 37 eventually reaches the inlet of the compression device 4, so that a new thermodynamic cycle can occur within the refrigerant circuit 2.

[0089] Fig. 9 Shows the corresponding Figure 7 The operating mode and Figure 8 A combination of operating modes. Fig. 9 This operating mode of the vehicle cools both the vehicle cabin interior and the components of the vehicle's electric powertrain, which may occur, for example, when the vehicle is in a fast charging phase or is traveling at high speed under high outside temperature conditions.

[0090] Part I 14 Refrigerant Behavior and Figure 7 or Figure 8 The behavior is the same and can be described with reference to the description of these figures.

[0091] exist Fig. 9 In the case where the second portion 15 and the branch 20 are active, the second heat exchanger 17 and the third heat exchanger 22 are simultaneously operated as evaporators.

[0092] At the branching point 29, the refrigerant is divided and circulated through each internal heat exchanger 36, 37. The first expansion device 16 and the second expansion device 21 utilize the expansion of the refrigerant, and then the refrigerant evaporates in the second heat exchanger 17 and the third heat exchanger 22. The refrigerant leaving the second channel 39 of the first internal heat exchanger 36 and the second channel 42 of the second internal heat exchanger 37 are combined at the junction 32 and then reach the inlet of the compression device 4, so that a new thermodynamic cycle can occur in the refrigerant circuit 2.

[0093] Fig.10 An operating mode is shown, which is called the mode for heating the interior of the vehicle cabin by recovering thermal energy from components of the electric powertrain. This is very beneficial for executing the thermodynamic cycle that takes place in the refrigerant circuit 2. This operating mode thus allows heating the internal air flow 8 using energy that would otherwise be lost by dissipation into the external air flow.

[0094] To this end, the first heat exchanger 5 unloads the thermal energy generated by the compression device 4 into the heat transfer liquid. The pump 13 is active and the hot heat transfer liquid can then reach the first heat exchanger 12 and thus heat the internal air flow 18 sent to the interior of the vehicle cabin. The refrigerant is thus condensed and its liquid phase is stored in the accumulator 6, whether it is downstream or integrated into the first heat exchanger 5.

[0095] The first valve 23 is in a closed position, thereby preventing any circulation of the refrigerant to the fourth heat exchanger 10. The second valve 25 is in an open position, so as to allow the circulation of the refrigerant through the pipe 33. The second expansion device 21 is open and expands the refrigerant. Thus, the branch 20 is functional and the third heat exchanger 22 operates as an evaporator. The liquid refrigerant passes through the first channel 40 of the second internal heat exchanger 37 and reaches the second expansion device 21. The refrigerant then evaporates while flowing through the third heat exchanger 22, which is traversed by an additional heat transfer liquid 9, which exchanges heat with one or another component of the electric power train, such as those listed above. Thus, thermal energy is recovered from the electric power train and used to operate the evaporation phase of the thermodynamic cycle.

[0096] The first expansion device 16 is placed in a closed position to prevent any circulation of refrigerant in the second portion 15 of the refrigerant circuit 2 .

[0097] The thermal management system 1 according to the first embodiment, according to the second embodiment or according to the third embodiment may include means for acquiring information related to the refrigerant circuit 2, the heat transfer liquid circuit 3, one of the components of the electric powertrain (in particular an electric storage device) or the interior of the vehicle cabin, as well as means for acting on the components of the thermal management system to achieve fixed set points, in particular regarding the internal air flow 18, the temperature of the refrigerant or regarding the rotational speed of the compression device 4. This control of the thermal management system 1 can be performed by a control device, which can take the form of an electronic unit or a box. The control device is advantageously capable of operating the compression device 4, valves, expansion devices, pumps and / or means for circulating the heat transfer liquid. Thus, the control device acts on the rotational speed of the compression device, in particular when the compression device is a fixed displacement compressor with a built-in electric motor.

[0098] As can be understood from the foregoing, the invention thus makes it possible in a simple manner and at optimized cost to provide thermal management of a component of an electric powertrain (e.g. a battery or battery pack) and / or of the interior of the vehicle cabin by heating or cooling. The objects set for the invention are achieved by providing a thermal management system which performs, with reduced means, the functions of cooling the interior of the vehicle cabin, of recovering energy from a component of the electric powertrain, and of providing thermal management of one of the components of the vehicle electric powertrain.

[0099] The present invention is by no means limited to the devices and configurations described and illustrated herein, but also extends to any equivalent devices or configurations and any technically operable combination of such devices. In particular, as long as the architecture of the refrigerant circuit or heat transfer liquid loop achieves the functions described in this document, it can be modified without impairing the present invention.

Claims

1. A vehicle thermal management system (1), comprising at least a refrigerant circuit (2), a loop for a heat transfer liquid (3) and a first heat exchanger (5), wherein the first heat exchanger thermally connects the loop for the heat transfer liquid (3) to the refrigerant circuit (2), the loop for the heat transfer liquid (3) comprising at least one heat exchanger configured to dissipate heat energy into an air flow, the refrigerant circuit (2) comprising at least a compression device (4), the first heat exchanger (5), a refrigerant accumulation device (6), a first expansion device (16) and a second heat exchanger (17), the second heat exchanger being designed to allow an internal air flow (18) to pass through the vehicle compartment interior, characterized in that The refrigerant circuit (2) comprises a branch (20) arranged in parallel with the first expansion device (16) and the second heat exchanger (17), the branch (20) comprising a third heat exchanger (22) and a second expansion device (21) capable of being thermally coupled to at least one component of the vehicle's electric powertrain; wherein the refrigerant circuit (2) comprises a branch point (29) where the branch (20) starts and a junction point (32) where the branch (20) ends, the refrigerant circuit (2) comprises an internal heat exchanger (26), the internal heat exchanger comprises a first channel (27) and a second channel (30), the first channel and the second channel being configured to allow refrigerant to pass through them, the second channel (30) of the internal heat exchanger (26) being located between the junction point (32) and the inlet of the compression device (4); wherein the refrigerant circuit (2) comprises a fourth heat exchanger (10) designed to be passed through by an external air flow (19) of a vehicle compartment and positioned between an outlet of the refrigerant storage device (6) and the branch point (29); wherein the heat exchanger of the circuit (3) for heat transfer liquid is a radiator (35) designed to be traversed by an external air flow (19) of the vehicle cabin; Wherein, according to the flow direction of air flow passing through the fourth heat exchanger and the radiator, the fourth heat exchanger (10) is upstream of the radiator (35).

2. The system according to claim 1, wherein: The first expansion device (16) and the second expansion device (21) are configured to cut off any flow of refrigerant towards the second heat exchanger (17) and towards the third heat exchanger (22), respectively.

3. The system according to claim 1, wherein: The refrigerant circuit (2) comprises at least one check valve (34) located between the outlet of the fourth heat exchanger (10) and the branch point (29).

4. The system according to any one of claims 1 to 3, wherein: The heat exchanger of the circuit (3) for heat transfer liquid is a unit heater (12) designed to be traversed by the internal air flow (18) conveyed to the interior of the vehicle cabin.

5. The system according to any one of claims 1 to 3, wherein: The refrigerant storage device (6) is a desiccant bottle.

6. A vehicle thermal management system (1), comprising at least a refrigerant circuit (2), a loop for a heat transfer liquid (3) and a first heat exchanger (5), wherein the first heat exchanger thermally connects the loop for the heat transfer liquid (3) to the refrigerant circuit (2), the loop for the heat transfer liquid (3) comprising at least one heat exchanger configured to dissipate heat energy into an air flow, the refrigerant circuit (2) comprising at least a compression device (4), the first heat exchanger (5), a refrigerant accumulation device (6), a first expansion device (16) and a second heat exchanger (17), the second heat exchanger being designed to allow an internal air flow (18) delivered to the interior of a vehicle compartment to pass through, characterized in that The refrigerant circuit (2) comprises a branch (20) arranged in parallel with the first expansion device (16) and the second heat exchanger (17), the branch (20) comprising a third heat exchanger (22) and a second expansion device (21) capable of being thermally coupled to at least one component of the vehicle's electric powertrain; The refrigerant circuit (2) comprises a branch point (29) where the branch (20) starts and a junction point (32) where the branch (20) ends, the refrigerant circuit (2) comprises a first internal heat exchanger (36), and at least one channel (39) of the first internal heat exchanger is located between the outlet of the second heat exchanger (17) and the junction point (32); wherein the refrigerant circuit (2) comprises a fourth heat exchanger (10) designed to be passed through by an external air flow (19) of a vehicle compartment and positioned between an outlet of the refrigerant storage device (6) and the branch point (29); wherein the heat exchanger of the circuit (3) for heat transfer liquid is a radiator (35) designed to be traversed by an external air flow (19) of the vehicle cabin; Wherein, according to the flow direction of air flow passing through the fourth heat exchanger and the radiator, the fourth heat exchanger (10) is upstream of the radiator (35).

7. The system according to claim 6, wherein: The refrigerant circuit (2) comprises a second internal heat exchanger (37), at least one channel (42) of which is located between the outlet of the third heat exchanger (22) and the junction (32).

8. The system according to claim 6 or 7, wherein: The first expansion device (16) and the second expansion device (21) are configured to cut off any flow of refrigerant towards the second heat exchanger (17) and towards the third heat exchanger (22), respectively.

9. The system according to claim 6 or 7, wherein: The refrigerant circuit (2) comprises at least one check valve (34) located between the outlet of the fourth heat exchanger (10) and the branch point (29).

10. The system according to claim 6 or 7, wherein: The heat exchanger of the circuit (3) for heat transfer liquid is a unit heater (12) designed to be traversed by the internal air flow (18) conveyed to the interior of the vehicle cabin.

11. The system according to claim 6 or 7, wherein: The refrigerant storage device (6) is a desiccant bottle.

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