Thermal conditioning system

Abstract

The invention relates to a thermal conditioning system (100) for a motor vehicle, comprising a refrigerant circuit (10) having: - a main loop (A) comprising successively: - a compressor (7), - a first heat exchanger (1) thermally coupled with a first interior airflow (Fi1) to a passenger compartment of the vehicle, - a first expansion valve (31), - a second heat exchanger (2) thermally coupled with an exterior airflow (Fe) to the passenger compartment, - a first branch (B) comprising successively a second expansion valve (32) and a third heat exchanger (3), - a second branch (C) comprising successively a third expansion valve (33) and a fourth heat exchanger (4) thermally coupled with the first interior airflow (Fi1),- a third branch (D) connecting a point on the main loop (A) located downstream of the first exchanger (1) to a point on the main loop (A) located upstream of the first pressure reducer (31). Figure 2,

Description

Title of the invention: Thermal conditioning system technical field

[0001] The present invention relates to the field of thermal conditioning systems. Such systems can, for example, be fitted to motor vehicles. These systems ensure thermal regulation of various vehicle components, such as the passenger compartment or an electrical energy storage battery, when the vehicle is electrically powered. Heat exchange is managed primarily by the compression and expansion of a refrigerant circulating in a circuit containing several heat exchangers. A compressor forces the refrigerant into a high-pressure state, allowing its circulation within the circuit. Previous technique

[0002] Chemical refrigerants generally have a high global warming potential (GWP), which is a disadvantage. Carbon dioxide, which by definition has a global warming potential of one, can also be used as a refrigerant. To optimize energy efficiency, it is useful to have multiple operating modes available in order to make the best use of the various available heat sources.

[0003] The ability to manage numerous different operating modes, thus optimizing energy consumption under many different operating conditions, generally requires the use of a large number of expansion devices and valves, these devices being electronically controlled. The cost and complexity of the thermal conditioning system therefore tend to increase.

[0004] There is therefore a need for a simplified thermal conditioning system, while still allowing for numerous operating modes and simplified control of these different operating modes. Summary

[0005] To this end, a thermal conditioning system for motor vehicles is proposed, comprising a refrigerant circuit configured to circulate a refrigerant, the refrigerant circuit comprising: - a main loop comprising successively, according to the direction of refrigerant flow: — a compressor, — a first heat exchanger thermally coupled with a first flow of air inside a vehicle passenger compartment, — a first regulator, — a second heat exchanger thermally coupled with an outside airflow to the vehicle's passenger compartment, — a refrigerant fluid accumulation device, - a first branch connecting a first connection point located on the main loop downstream of the first heat exchanger and upstream of the first expansion valve to a second connection point located on the main loop downstream of the second heat exchanger and upstream of the storage device, the first branch successively comprising a second expansion valve and a third heat exchanger, - a second branch connecting a third connection point located on the main loop downstream of the first exchanger and upstream of the first connection point to a fourth connection point located on the main loop downstream of the second connection point and upstream of the accumulation device, the second branch of the line comprising successively a third expansion valve and a fourth heat exchanger thermally coupled with the first internal airflow, - a third branch connecting a fifth connection point located on the main loop downstream of the first heat exchanger and upstream of the third connection point to a sixth connection point located on the main loop downstream of the first connection point and upstream of the first pressure regulator.

[0006] The features listed in the following paragraphs can be implemented independently of each other or in any technically feasible combination:

[0007] The fourth connection point can be confused with the second connection point.

[0008] The first exchanger is configured to operate as a condenser or as a refrigerant fluid cooler.

[0009] The first heat exchanger allows the vehicle's passenger compartment to be heated.

[0010] According to one embodiment, the first heat exchanger is configured to exchange heat with the first airflow inside the vehicle's passenger compartment.

[0011] According to one embodiment, the first heat exchanger is configured to exchange heat with a heat transfer fluid circulating in a closed heat transfer fluid circuit, the heat transfer fluid circuit comprising a heat exchanger heat configured to exchange heat with the first flow of air inside the vehicle's passenger compartment.

[0012] The second exchanger is configured to operate selectively either as a condenser or refrigerant cooler, or as a refrigerant evaporator.

[0013] The second exchanger allows heat to be selectively dissipated into the outside airflow, or heat to be received from the outside airflow.

[0014] According to one embodiment, the second exchanger is configured to exchange heat with the outside airflow to the vehicle's passenger compartment.

[0015] According to one embodiment, the second exchanger is configured to exchange heat with a heat transfer fluid circulating in a closed heat transfer fluid circuit, the heat transfer fluid circuit comprising a heat exchanger configured to exchange heat with the outside airflow to the vehicle's passenger compartment.

[0016] The third heat exchanger is configured to operate as a refrigerant fluid evaporator.

[0017] The fourth heat exchanger is configured to operate as a refrigerant fluid evaporator.

[0018] The fourth heat exchanger can cool the first flow of air inside the passenger compartment, so as to cool a first part of the passenger compartment, for example the front part.

[0019] The fourth exchanger is arranged upstream of the first exchanger according to a flow direction of the first internal airflow.

[0020] According to one aspect of the thermal conditioning system, the refrigerant circuit includes a first one-way valve disposed on the main loop between the fifth connection point and the third connection point, the first one-way valve being configured to allow refrigerant flow through the first one-way valve only from the fifth connection point to the third connection point.

[0021] According to another aspect of the thermal conditioning system, the refrigerant circuit includes a second one-way valve disposed on the third branch between the fifth connection point and the sixth connection point, the second one-way valve being configured to allow refrigerant flow through the second one-way valve only from the fifth connection point to the sixth connection point.

[0022] The first one-way valve is configured to allow refrigerant fluid to circulate through the first one-way valve from the fifth connection point to the third connection point, and is configured to prohibit refrigerant fluid to circulate through the first one-way valve from the third connection point to the fifth connection point.

[0023] The second one-way valve is configured to allow refrigerant fluid to circulate through the second one-way valve from the fifth connection point to the sixth connection point, and is configured to prohibit refrigerant fluid to circulate through the second one-way valve from the sixth connection point to the fifth connection point.

[0024] According to one embodiment of the thermal conditioning system, the third heat exchanger is thermally coupled with an element of an electric traction chain of a motor vehicle.

[0025] The third heat exchanger allows the element of the vehicle's electric powertrain to be cooled, or the heat losses of this powertrain element to be recovered.

[0026] According to one embodiment, the element of the vehicle's electric drive chain includes an electrical energy storage battery.

[0027] Alternatively or in addition, the element of the vehicle's electric drive chain includes an electric vehicle traction motor.

[0028] Alternatively or in addition, the element of the vehicle's electric traction chain includes an electronic control unit for the vehicle's electric traction motor.

[0029] According to one embodiment, the third heat exchanger is thermally coupled with the element of the electric traction chain via a heat transfer fluid circulating in a heat transfer fluid circuit.

[0030] According to one embodiment of the thermal conditioning system, the refrigerant circuit comprises: - a fourth branch connecting a seventh connection point located on the main loop downstream of the first interchange and upstream of the first connection point to an eighth connection point located on the second branch downstream of the fourth interchange and upstream of the fourth connection point, the fourth branch of the bypass comprising successively a fourth expansion valve and a fifth heat exchanger configured to exchange heat with a second flow of indoor air.

[0031] The fifth heat exchanger is configured to operate as a refrigerant fluid evaporator.

[0032] The fifth heat exchanger allows the second flow of air inside the passenger compartment to be cooled, so as to particularly cool a second area of ​​the passenger compartment.

[0033] According to one embodiment, the fourth branch includes a fifth expansion valve disposed downstream of the fifth heat exchanger. In other words, the fourth branch comprises successively a fourth expansion valve, a fifth heat exchanger configured to exchange heat with a second internal airflow, and a fifth expansion valve.

[0034] The fifth expansion valve allows the third and fifth exchangers to operate at different evaporation pressures.

[0035] The seventh connection point can be confused with the third connection point.

[0036] The seventh connection point can be confused with the first connection point.

[0037] According to one variant, the fourth branch connects a seventh connection point located on the first branch downstream of the first connection point and upstream of the second regulator to an eighth connection point located on the second branch downstream of the fourth exchanger and upstream of the fourth connection point. The third branch of the bypass successively comprises a fourth expansion valve and a fifth heat exchanger configured to exchange heat with a second stream of indoor air.

[0038] According to one embodiment of the thermal conditioning system, the refrigerant circuit includes a fifth branch connecting a ninth connection point located on the main loop downstream of a compressor outlet and upstream of the first exchanger to a tenth connection point located on the main loop downstream of the second heat exchanger and upstream of the storage device, the fifth branch including a sixth expansion valve.

[0039] The fifth branch of the bypass allows the refrigerant fluid from the compressor to be sent to the second heat exchanger, in order to cool it, in particular for operating modes involving cooling of the vehicle's passenger compartment.

[0040] According to one embodiment of the thermal conditioning system, the main loop of the refrigerant circuit includes an internal exchanger configured to allow heat exchange between the refrigerant circulating between the first connection point and the first expansion valve and the refrigerant downstream of the accumulation device and upstream of a compressor inlet.

[0041] The internal exchanger makes it possible to increase the enthalpy variation of the refrigerant during the thermodynamic cycle, and therefore to increase the thermal power that the thermal conditioning system can provide.

[0042] The internal heat exchanger includes a first heat exchange section arranged on the main loop between the first connection point and the first expansion valve.

[0043] The internal heat exchanger includes a second heat exchange section arranged on the main loop downstream of the accumulator and upstream of the compressor inlet.

[0044] The internal heat exchanger is configured to allow heat exchange between the refrigerant in the first heat exchange section and the refrigerant in the second heat exchange section.

[0045] The first heat exchange section is arranged between the first connection point and the sixth connection point.

[0046] The main loop includes a first shut-off valve located upstream of the first exchanger.

[0047] The first shut-off valve is located downstream of the ninth connection point.

[0048] The main loop includes a second shut-off valve located downstream of the second heat exchanger and upstream of the second connection point.

[0049] The second shut-off valve is arranged between the tenth connection point and the second connection point.

[0050] The first shut-off valve is an electrically operated valve. The second shut-off valve is an electrically operated valve.

[0051] The first shut-off valve is a two-way valve. Similarly, the second shut-off valve is a two-way valve.

[0052] According to one embodiment, the refrigerant circuit includes a third one-way valve disposed on the second branch between the fourth exchanger and the eighth connection point, the third one-way valve being configured to allow refrigerant flow through the third one-way valve from the fourth exchanger to the eighth connection point, and being configured to prohibit refrigerant flow through the third one-way valve from the eighth connection point to the fourth exchanger.

[0053] According to another embodiment, the refrigerant circuit includes a third one-way valve disposed on the second branch between the eighth connection point and the fourth connection point, the third one-way valve being configured to allow refrigerant to circulate through the third one-way valve of the eighth connection point to the fourth connection point, and being configured to prohibit refrigerant fluid circulation through the third one-way valve from the fourth connection point to the eighth connection point.

[0054] Each of the one-way valves is a check valve.

[0055] Alternatively, each of the one-way valves can be an electrically operated valve.

[0056] The invention also relates to a method of operating a thermal conditioning system as described above, in a so-called dehumidification mode in which: - A first flow of refrigerant circulates in the compressor where it is under high pressure, and circulates in the main loop, in the first heat exchanger where it releases heat, and divides into: — a second flow circulating in the main loop, then in the second bypass branch, successively in the third expansion valve where it undergoes expansion and passes to a low pressure lower than the high pressure, in the fourth exchanger where it receives heat, and — a third flow circulating in the third branch of the bypass, then in the main loop, successively in the first expansion valve where it undergoes expansion and passes to low pressure, in the second exchanger where it receives heat, and joins the flow of refrigerant fluid coming from the fourth exchanger, the total flow formed circulates in the accumulation device and returns to the compressor.

[0057] In this operating mode: The refrigerant flow rate in the portion of the main loop downstream of the third connection point and upstream of the sixth connection point is zero. The refrigerant flow rate in the first branch is zero. The refrigerant flow rate in the fourth branch of the bypass is zero. The refrigerant flow rate in the fifth branch of the bypass is zero.

[0058] The first exchanger heats the first flow of indoor air. The second exchanger evaporates the refrigerant, with the heat of vaporization being supplied by the outside airflow. The fourth exchanger also evaporates the refrigerant, with the heat of vaporization being supplied by the first flow of indoor air. The fifth exchanger is thermally inactive, meaning there is no heat exchange between the refrigerant and the second indoor airflow. The internal heat exchanger is thermally inactive. Indeed, the first heat exchange section is not traversed by any refrigerant fluid.

[0059] In this operating mode, the first flow of interior air is cooled at the fourth heat exchanger and heated at the first heat exchanger. The passenger compartment is thus dehumidified. Brief description of the drawings

[0060] Other features, details and advantages will become apparent upon reading the detailed description below, and upon analysis of the accompanying drawings, on which:

[0061] [Fig. 1] is a schematic view of a thermal conditioning system according to a first embodiment of the invention,

[0062] [Fig.2] is a schematic view of a thermal conditioning system according to a second embodiment of the invention,

[0063] [Fig.3] is a schematic view of a thermal conditioning system according to a first variant of the second embodiment,

[0064] [Fig.4] is a schematic view of a thermal conditioning system according to a second variant of the second embodiment,

[0065] [Fig.5] is a schematic view of a thermal conditioning system according to a third embodiment of the invention,

[0066] [Fig.6] is a schematic view of the thermal conditioning system of the [Fig.2], operating according to a mode of operation called dehumidification mode,

[0067] [Fig.7] is a schematic view of the thermal conditioning system of the [Fig.5], operating according to the operating mode known as dehumidification mode. Description of the implementation methods

[0068] To facilitate reading the figures, the various elements are not necessarily drawn to scale. In these figures, identical elements bear the same reference numerals. Certain elements or parameters may be indexed, that is, designated, for example, as first element or second element, or first parameter and second parameter, etc. This indexing aims to differentiate similar, but not identical, elements or parameters. This indexing does not imply any priority of one element or parameter over another, and the designations may be interchanged.

[0069] In the following description, the expression "a first element upstream of a second element" means that the first element is placed before the second element with respect to the direction of flow, or path, of a fluid. Similarly, the term "a first element downstream of a second element" means The first element is positioned after the second element with respect to the direction of flow, or path, of the fluid in question. In the case of a refrigerant circuit, the term "a first element is upstream of a second element" means that the refrigerant flows successively through the first element, then the second element, without passing through the compression device. In other words, the refrigerant exits the compression device, possibly passes through one or more elements, then passes through the first element, then the second element, and then returns to the compression device, possibly after passing through other elements.

[0070] The expression "a second element is placed between a first element and a third element" means that the shortest path to go from the first element to the third element or from the third element to the first element passes through the second element.

[0071] When it is specified that a subsystem includes a given element, this does not exclude the presence of other elements in that subsystem.

[0072] The thermal conditioning system 100, which will be described below, comprises an electronic control unit that receives information from various sensors measuring, in particular, the characteristics of the refrigerant at various points in the circuit. The electronic control unit also receives instructions from the vehicle occupants, such as the desired temperature inside the passenger compartment. The electronic control unit can also receive instructions from other electronic subsystems, such as the battery management system for electrical energy storage. The electronic control unit implements control laws to operate the various actuators in order to control the thermal conditioning system 100 and ensure compliance with the received instructions.

[0073] A compression device 7, also called a compressor, allows a refrigerant to circulate in a refrigerant circulation circuit 10. The compression device 7 can be an electric compressor, that is, a compressor whose moving parts are driven by an electric motor. The compression device 7 has a low-pressure refrigerant intake side, also called the inlet 7a of the compression device, and a high-pressure refrigerant discharge side, also called the outlet 7b of the compression device 7. The internal moving parts of the compressor 7 cause the refrigerant to pass from a low pressure at the inlet 7a to a high pressure at the outlet 7b. After expansion in one or more expansion chambers and circulation in at least part of the circuit, the refrigerant returns to the inlet 7a of the compressor 7 and begins a new thermodynamic cycle.

[0074] The refrigerant circuit 10 forms a closed circuit in which the refrigerant can circulate. The refrigerant circuit 10 is leak-proof when it is in its nominal operating condition, that is, without any faults or leaks. Each connection point of the circuit 10 allows the refrigerant to flow into one or the other of the circuit sections that converge at that connection point. The distribution of the refrigerant between the circuit sections that converge at a connection point is achieved by opening or closing the shut-off valves, check valves, or expansion devices included on each of these sections. In other words, each connection point is a means of redirecting the refrigerant arriving at that connection point.Various shut-off valves and check valves thus allow the refrigerant to be selectively directed into the different branches of the refrigerant circuit, in order to ensure different operating modes, as will be described later.

[0075] The refrigerant used by the refrigerant circuit 10 is a natural refrigerant, such as R744. R290 can also be used. It is also possible to use a chemical refrigerant, such as R1234yf or R134a.

[0076] Each refrigerant expansion device, also called an expansion valve, can be an electronic expansion valve. In an electronic expansion valve, the passage area through which the refrigerant passes can be continuously adjusted between a closed position and a maximum open position. To achieve this, an electronic control module for the expansion valve drives an electric motor that moves a movable shutter, thus controlling the passage area available to the refrigerant.

[0077] Interior airflow refers to the flow of air directed towards the passenger compartment of a motor vehicle. Interior airflow may circulate within a heating, ventilation, and / or air conditioning (HVAC) system. A vehicle may be equipped with several HVAC systems. For example, one system may manage the front area of ​​the passenger compartment, and a second system may manage the rear area. These installations have not been shown in the various figures. One or more motor-fan units, not shown, are installed in each heating, ventilation and / or air conditioning system in order to increase, if necessary, the flow rate of the indoor air supplied by that system.

[0078] The term "external airflow Fe" refers to an airflow that is not directed towards the vehicle's passenger compartment. In other words, this airflow Fe remains outside the vehicle's passenger compartment. Another motor-fan assembly, also not shown, can be activated to increase the flow rate of the external airflow Fe if necessary.

[0079] The airflow provided by each of the motor-fan groups can be adjusted in real time according to the heat exchange requirements, for example by the electronic control unit of the thermal conditioning system 100.

[0080] The term "first exchanger" is equivalent to the term "first heat exchanger". Similarly, the term "internal exchanger" is equivalent to the term "internal heat exchanger". The term "storage device" is equivalent to the term "refrigerant storage device".

[0081] The heat transfer fluid circuit(s) also form one or more closed and sealed circuits in which a heat transfer fluid can circulate.

[0082] Figure [Fig.1] shows a thermal conditioning system 100 for a motor vehicle, according to a first embodiment. The thermal conditioning system 100 includes a refrigerant fluid circuit 10 configured to circulate a refrigerant fluid. The refrigerant circuit 10 comprises a main loop A consisting successively, according to the direction of refrigerant flow: - a 7-inch compressor, - a first heat exchanger 1 thermally coupled with a first internal airflow Fil to a vehicle passenger compartment, - a first regulator 31, - a second heat exchanger 2 thermally coupled with an external airflow Fe to the vehicle's passenger compartment, - a refrigerant fluid accumulation device 8. The refrigerant circuit 10 includes a first branch B connecting a first connection point 11 located on the main loop A downstream of the first heat exchanger 1 and upstream of the first expansion valve 31 to a second connection point 12 located on the main loop A downstream of the second heat exchanger 2 and upstream of the storage device 8. The first branch B includes successively a second expansion valve 32 and a third heat exchanger 3. The refrigerant circuit 10 includes a second branch C connecting a third connection point 13 located on the main loop A downstream of the first exchanger 1 and upstream of the first connection point 11 to a fourth connection point 14 located on the main loop A downstream of the second connection point 12 and upstream of the storage device 8. The second branch C includes successively a fourth expansion valve 34 and a fourth heat exchanger 4 thermally coupled with the first indoor airflow Fil. The refrigerant circuit 10 includes a third branch D connecting a fifth connection point 15 located on the main loop A downstream of the first exchanger 1 and upstream of the third connection point 13 to a sixth connection point 16 located on the main loop A downstream of the first connection point 11 and upstream of the first expansion valve 31.

[0083] In the example shown, the fourth connection point 14 can be confused with the second connection point 12.

[0084] The first exchanger 1 is configured to operate as a refrigerant fluid condenser or as a refrigerant fluid cooler, when the refrigerant fluid is in a supercritical state. The first heat exchanger 1 is used to heat the passenger compartment of the vehicle.

[0085] The first interior airflow Fil is for example an airflow blown at the front part of the vehicle's passenger compartment.

[0086] The thermal coupling between the first exchanger 1 and the first internal airflow Fil can be achieved in different ways.

[0087] According to embodiments of Figures 1 to 3, as well as according to embodiment of [Fig.5], the first heat exchanger 1 is configured to exchange heat with the first interior airflow Fil to the vehicle's passenger compartment. The thermal coupling between the first heat exchanger 1 and the first indoor airflow Fil is then said to be direct. The first internal airflow (Fil) circulates over an external surface of the first heat exchanger 1. The refrigerant circulates inside the first heat exchanger 1.

[0088] According to an alternative embodiment, illustrated in [Fig.4], the first heat exchanger 1 is configured to exchange heat with a heat transfer fluid circulating in a closed heat transfer fluid circuit 40, the heat transfer fluid circuit 40 comprising a heat exchanger IA configured to exchange heat with the first interior airflow Fil to the vehicle's passenger compartment. The thermal coupling between the first heat exchanger 1 and the first indoor airflow Fil is then said to be indirect, since it is achieved through a heat transfer fluid. The heat transfer fluid in circuit 40 can be, for example, a mixture of water and glycol.

[0089] In the case of direct thermal coupling, the first heat exchanger 1 is disposed in a first heating, ventilation and / or air conditioning installation. In the case of indirect thermal coupling, the IA exchanger, known as a heating radiator, is placed in a first heating, ventilation and / or air conditioning installation. The first internal airflow Fil circulates over an external surface of the heating radiator IA. The heat transfer fluid circulates inside the heating radiator IA.

[0090] The second heat exchanger 2 is configured to operate selectively either as a condenser or refrigerant cooler, or as a refrigerant evaporator. As before, the second exchanger 2 can operate as a refrigerant cooler when this exchanger receives refrigerant in a supercritical state.

[0091] The second exchanger 2 allows to selectively either dissipate heat into the outside airflow Fe, or receive heat from the outside airflow Fe. Indeed, the second exchanger 2 can, depending on the operating mode activated, receive either high-pressure, high-temperature refrigerant or low-pressure, two-phase refrigerant. This two-phase state comprises a mixture of liquid and vapor, the proportion of liquid and vapor being able to vary according to the operating conditions.

[0092] In a manner analogous to the first exchanger 1, the thermal coupling between the second exchanger 2 and the outside air flow Fe can be ensured in different ways.

[0093] According to embodiments of figures 1 to 3 and 5, the second exchanger 2 is configured to exchange heat with the outside airflow Fe to the vehicle's passenger compartment. The thermal coupling between the second exchanger 2 and the outside airflow Fe is then said to be direct. The second intercooler 2 is, for example, installed in the front of the vehicle, just behind the grille, so as to directly receive the airflow resulting from the vehicle's forward movement. The second interchange 2 could also be placed in a wheel arch of the vehicle.

[0094] According to an alternative embodiment, corresponding to [Fig. 4], the second heat exchanger 2 is configured to exchange heat with a heat transfer fluid circulating in a closed heat transfer fluid circuit 50. The heat transfer fluid circuit 50 includes a heat exchanger 2A configured to exchange heat with the outside airflow Fe to the vehicle's passenger compartment. The thermal coupling between the second exchanger 2 and the outside air flow Fe is then said to be indirect. As before, the heat transfer fluid in circuit 50 can be, for example, a mixture of water and glycol.

[0095] The third heat exchanger 3 is configured to operate as a refrigerant fluid evaporator. Indeed, the third exchanger 3 can receive refrigerant fluid in a two-phase state at low pressure.

[0096] The fourth heat exchanger 4 is configured to operate as a refrigerant fluid evaporator. Indeed, the fourth exchanger 4 can receive refrigerant fluid in a two-phase state at low pressure.

[0097] The fourth heat exchanger 4 can cool the first interior airflow Fil to the passenger compartment, so as to cool a first part of the passenger compartment, for example the front part of the passenger compartment.

[0098] The fourth exchanger 4 is disposed in the first heating, ventilation and / or air conditioning installation. The fourth exchanger 4 is arranged upstream of the first exchanger 1 according to a flow direction of the first internal air flow Fil. In other words, the first indoor airflow Fil exchanges heat first with the fourth exchanger 4, then with the first exchanger 1.

[0099] As before, the fourth heat exchanger 4 can also indirectly cool the first interior airflow Fil. This indirect heat exchange occurs via a heat transfer fluid circulating in a heat transfer fluid circuit 40B. This configuration is shown in the variant of [Fig. 4]. In this case, the heat transfer fluid circuit 40B includes a heat exchanger 4A configured to exchange heat with the first interior airflow Fil in the vehicle's passenger compartment.

[0100] The refrigerant circuit 10 includes a first one-way valve 45 disposed on the main loop A between the fifth connection point 15 and the third connection point 13. The first one-way valve 45 is configured to allow refrigerant to circulate through the first one-way valve 45 only from the fifth connection point 15 to the third connection point 13.

[0101] The first one-way valve 45 is configured to allow refrigerant fluid to circulate through the first one-way valve 45 from the fifth connection point 15 to the third connection point 13. The first one-way valve 45 is configured to prohibit refrigerant fluid circulation through the first one-way valve 45 from the third connection point 13 to the fifth connection point 15. Thus, the first one-way valve 45 makes it possible to prohibit a circulation of refrigerant fluid in the main loop A from the third connection point 13 to the fifth connection point 15.

[0102] The refrigerant circuit 10 includes a second one-way valve 46 disposed on the third branch branch D. The second one-way valve 46 is disposed between the fifth connection point 15 and the sixth connection point 16. The second one-way valve 46 is configured to allow refrigerant to circulate through the second one-way valve 46 only from the fifth connection point 15 to the sixth connection point 16.

[0103] The second one-way valve 46 is configured to allow refrigerant fluid to circulate through the second one-way valve 46 from the fifth connection point 15 to the sixth connection point 16. The second one-way valve 46 is configured to prohibit refrigerant fluid to circulate through the second one-way valve 46 from the sixth connection point 16 to the fifth connection point 15. The second one-way valve 46 allows for the prohibition of refrigerant circulation in the third branch of the bypass D from the sixth connection point 16 to the fifth connection point 15.

[0104] The use of a first one-way valve 45 and a second one-way valve 46 avoids the need for an expansion valve on the portion of the main loop A between the outlet of the first heat exchanger 1 and the fifth connection point 15. Since the cost of two one-way valves is lower than the cost of an expansion valve, the overall cost of the heat conditioning system can thus be reduced. Even though the expansion rate at the outlet of the first heat exchanger cannot be controlled with the same precision as when an expansion valve is present, the performance loss is moderate and the potential cost reduction is advantageous.

[0105] According to the illustrated example, the third heat exchanger 3 is thermally coupled with an element 25 of an electric drive chain of a motor vehicle. The third heat exchanger 3 allows the element 25 of the vehicle's electric powertrain to be cooled, or the heat losses of this element 25 of the powertrain to be recovered.

[0106] According to one embodiment, element 25 of the vehicle's electric drive chain includes an electrical energy storage battery. The third exchanger 3 thus makes it possible in particular to cool the battery, for example during a charging phase, or to recover at least part of the heat dissipated by the passage of electric current in the battery. Alternatively, or in addition, element 25 of the vehicle's electric drivetrain includes a vehicle traction electric motor. Alternatively, or in addition, element 25 of the vehicle's electric drivetrain includes an electronic control unit for the vehicle traction electric motor.

[0107] The third heat exchanger 3 is here thermally coupled with the element 25 of the electric traction chain by means of a heat transfer fluid circulating in a heat transfer fluid circuit 30. The heat transfer fluid in circuit 30 can be, for example, a mixture of water and glycol. Circuit 30 includes a pump, not shown, which circulates the heat transfer fluid. The pump is, for example, an electric pump, which can be selectively switched on or off.

[0108] Fig. 2 represents a second embodiment of the thermal conditioning system 100.

[0109] In this second embodiment, the refrigerant circuit 10 includes a fourth branch E connecting a seventh connection point 17 located on the main loop A downstream of the first heat exchanger 1 and upstream of the first connection point 11 to an eighth connection point 18 located on the second branch C downstream of the fourth heat exchanger 4 and upstream of the fourth connection point 14. The third branch of the D branch includes successively a fourth expansion valve 34 and a fifth heat exchanger 5 configured to exchange heat with a second indoor airflow Fi2.

[0110] The fifth heat exchanger 5 is configured to operate as a refrigerant fluid evaporator. The fifth heat exchanger 5 allows the second interior airflow Fi2 to be cooled to the passenger compartment, in order to specifically cool a second area of ​​the passenger compartment. The fourth expansion valve 34 is located between the seventh connection point 17 and the fifth exchanger 5.

[0111] The second interior airflow Fi2 is, for example, an airflow blown at the rear of the vehicle's passenger compartment. Passengers seated at the rear of the vehicle thus receive a direct flow of cooled air, which has not been heated by passing through the front of the passenger compartment. The fifth heat exchanger 5 is, for example, located in a second heating, ventilation and / or air conditioning system, dedicated to the occupants of the rear seats of the vehicle.

[0112] As before, the fifth heat exchanger 5 can also indirectly cool the second interior airflow Fi2. This indirect heat exchange is achieved via a heat transfer fluid circulating in a 40C heat transfer fluid circuit. In this case, the 40C heat transfer fluid circuit includes a 5A heat exchanger configured to exchange heat with the second interior airflow Fi2 to the vehicle's passenger compartment.

[0113] In the variant of [Fig. 4], the heat exchangers 1, 2, 4, and 5 all perform indirect heat exchange. In the embodiments illustrated in the other figures, the heat exchange is direct for all these heat exchangers. According to variants not shown, some exchangers may perform a direct heat exchange, and other exchangers may perform an indirect heat exchange.

[0114] According to the second embodiment and its variants, the fourth branch E includes a fifth expansion valve 35 disposed downstream of the fifth heat exchanger 5. In other words, the fourth branch E successively comprises a fourth expansion valve 34, a fifth heat exchanger 5 configured to exchange heat with a second internal airflow Fi2, and a fifth expansion valve 35.

[0115] The fifth expansion valve 35 enables the operation of the third heat exchanger 3 and The fifth heat exchanger 5 has different evaporation pressures. The evaporation temperature of the refrigerant can therefore be different in the third heat exchanger 3 and in the fifth heat exchanger 5.

[0116] The seventh connection point 17 can be confused with the third connection point 13. This case is represented in [Fig.2]. According to an unrepresented variant, the seventh connection point 17 can be confused with the first connection point 11. The eighth connection point 18 can be confused with the fourth connection point 14, or with the second connection point 12.

[0117] According to a first variant of the second embodiment, illustrated in [Fig.3], the fourth branch E connects a seventh connection point 17 located on the first branch B downstream of the first connection point 11 and upstream of the second regulator 32 to an eighth connection point 18 located on the second branch C downstream of the fourth exchanger 4 and upstream of the fourth connection point 14. The third branch of the D branch includes successively a fourth expansion valve 34 and a fifth heat exchanger 5 configured to exchange heat with a second indoor airflow Fi2.

[0118] The refrigerant circuit 10 includes a fifth branch F connecting a ninth connection point 19 located on the main loop A downstream of an outlet 7b of the compressor 7 and upstream of the first heat exchanger 1 to a tenth connection point 20 located on the main loop A downstream of the second heat exchanger 2 and upstream of the storage device 8. The fifth branch F includes a sixth expansion valve 36.

[0119] The fifth branch F allows the refrigerant fluid from the compressor 7 to be sent to the second heat exchanger 2, in order to cool it, in particular for operating modes involving cooling of the vehicle's passenger compartment.

[0120] The main loop A of the refrigerant circuit 10 includes an internal exchanger 6 configured to allow heat exchange between the refrigerant circulating between the first connection point 11 and the first expansion valve 31 and the refrigerant downstream of the storage device 8 and upstream of an inlet 7a of the compressor 7.

[0121] The internal exchanger 6 makes it possible to increase the enthalpy variation of the refrigerant during the thermodynamic cycle, and therefore to increase the thermal power that the thermal conditioning system 100 can provide.

[0122] The internal heat exchanger 6 has a first heat exchange section 6a arranged on the main loop A between the first connection point 11 and the first expansion valve 31. The internal heat exchanger 6 has a second heat exchange section 6b arranged on the main loop A downstream of the accumulator 8 and upstream of the inlet 7a of the compressor 7.

[0123] The internal heat exchanger 6 is configured to allow heat exchange between the refrigerant in the first heat exchange section 6a and the refrigerant in the second heat exchange section 6b.

[0124] The first heat exchange section 6a is arranged between the first connection point 11 and the sixth connection point 16.

[0125] The main loop A includes a first shut-off valve 41 arranged upstream of the first exchanger 1. According to the second embodiment and its variants, as well as according to the third embodiment, the first shut-off valve 41 is located downstream of the ninth connection point 19.

[0126] The main loop A includes a second shut-off valve 42 disposed downstream of the second heat exchanger 2 and upstream of the second connection point 12. According to the second embodiment and its variants, as well as according to the third embodiment, the second shut-off valve 42 is disposed between the tenth connection point 20 and the second connection point 12.

[0127] The first shut-off valve 41 is an electrically operated valve. The second shut-off valve 42 is an electrically operated valve.

[0128] The first shut-off valve 41 is a two-way valve. Similarly, the second shut-off valve 42 is a two-way valve.

[0129] According to the first embodiment, illustrated in [Fig. 1], the refrigerant circuit 10 includes a third one-way valve 47 disposed on the second branch C between the fourth heat exchanger 4 and the fourth connection point 14. The third one-way valve 47 is configured to allow refrigerant flow through the third one-way valve 47 from the fourth heat exchanger 4 to the fourth connection point 14, and is configured to prohibit refrigerant flow through the third one-way valve 47 from the fourth connection point 14 to the fourth heat exchanger 4.

[0130] According to the second embodiment and its variants, illustrated in Figures 2 to 4, the refrigerant circuit 10 includes a third one-way valve 47 disposed on the second branch C between the fourth heat exchanger 4 and the eighth connection point 18. The third one-way valve 47 is configured to allow refrigerant flow through the third one-way valve 47 from the fourth heat exchanger 4 to the eighth connection point 18, and is configured to prohibit refrigerant flow through the third one-way valve 47 from the eighth connection point 18 to the fourth heat exchanger 4.

[0131] According to the third embodiment, illustrated in [Fig. 5], the refrigerant circuit 10 includes a third one-way valve 47' disposed on the second branch C between the eighth connection point 18 and the fourth connection point 14. The third one-way valve 47 is configured to allow refrigerant flow through the third one-way valve 47 from the eighth connection point 18 to the fourth connection point 14, and is configured to prohibit refrigerant flow through the third one-way valve 47 from the fourth connection point 14 to the eighth connection point 18.

[0132] In the third embodiment, the fourth branch E is without a pressure regulator between the fifth exchanger 5 and the eighth connection point 18. In other words, the fifth pressure regulator 35 is not present. The fourth branch E does not include any pressure regulator located on the portion between the fourth heat exchanger 4 and the eighth connection point 18.

[0133] The third embodiment thus differs from the second embodiment by the arrangement of the third one-way valve 47 and by the suppression of the fifth regulator 35. The third embodiment includes the same branch lines and the same heat exchangers as the second embodiment.

[0134] Each of the one-way valves 45, 46, 47 is for example a non-return valve. Alternatively, each of the one-way valves 45, 46, 47 can be an electrically operated valve.

[0135] The proposed thermal conditioning system circuit 100 can operate in various modes. One particular mode of operation will now be described and illustrated in Figures 6 and 7.

[0136] In these figures, the portions of the circuit 10 in which a flow of refrigerant fluid circulates are shown in thick solid lines, while the portions in which the refrigerant fluid does not circulate are shown in thin dashed lines. The different arrows indicate the direction of refrigerant flow in the various portions of circuit 10 through which a refrigerant flow passes.

[0137] In steady state, the time variation of the mass of refrigerant in a heat exchanger is zero, and the refrigerant flow rate downstream of a heat exchanger is equal to the refrigerant flow rate upstream of that heat exchanger. Similarly, there is no accumulation of refrigerant in an expansion valve, and the flow rate of refrigerant downstream of an expansion valve is equal to the flow rate upstream of that expansion valve.

[0138] Fig. 6 schematically illustrates a method of operation of a thermal conditioning system 100 according to the second embodiment, in a so-called dehumidification mode. Figure 7 schematically illustrates the same operating process, with the thermal conditioning system 100 defined according to the third embodiment. In this operating mode, a first flow Qrl of refrigerant circulates in the compressor 7 where it is subjected to high pressure, and then circulates in the main loop A, in the first heat exchanger 1 where it releases heat, and is divided into: - a second flow Qr2 circulating in the main loop A, then in the second bypass branch C, successively in the third expansion valve 33 it undergoes expansion and passes to a low pressure lower than the high pressure, in the fourth exchanger 4 where it receives heat, and - a third flow Qr3 circulating in the third branch of the bypass D, then in the main loop A, successively in the first expansion valve 31 where it undergoes expansion and passes to low pressure, in the second exchanger 2 where it receives heat, and joins the refrigerant flow from the fourth exchanger 4. The total flow Qrl formed circulates in the accumulation device 8 and returns to the compressor 7.

[0139] In this operating mode: - The refrigerant flow rate in the portion of the main loop A included downstream of the third connection point 13 and upstream of the sixth connection point 16 is zero. - The flow rate of refrigerant fluid in the first branch of bypass B is zero. The second regulator 32 is indeed in the closed position. - The refrigerant flow rate in the fourth branch of the bypass E is zero. The fourth regulator 34 is in the closed position. - The refrigerant flow rate in the fifth branch of the bypass F is zero. The sixth regulator 36 is indeed in the closed position.

[0140] The first Qrl flow of refrigerant is divided at the fifth connection point 15. The second flow Qr2 of refrigerant, coming from the fourth exchanger 4, joins at the fourth connection point 14 the third flow Qr3, coming from the second exchanger 2.

[0141] The first exchanger 1 heats the first internal airflow Fil. The second exchanger 2 carries out the evaporation of the refrigerant fluid, the heat of vaporization being supplied by the outside air flow Fe. The fourth exchanger 4 also carries out the evaporation of the refrigerant, the heat of vaporization being supplied by the first internal airflow Fil. The fifth heat exchanger 5 is thermally inactive, meaning there is no heat exchange between the refrigerant and the second internal airflow Fi2. The internal heat exchanger 6 is also thermally inactive. This is because the first heat exchange section 6a does not carry any refrigerant.

[0142] In this operating mode, the first interior airflow Fil is cooled at the fourth exchanger 4 and is heated at the first exchanger 1. The passenger compartment is thus dehumidified.

[0143] The fourth expansion valve 34 and the sixth expansion valve 36 are in the closed position and block the circulation of refrigerant fluid.

[0144] Many other modes of operation, not shown, are of course possible.

Claims

1. Demands Thermal conditioning system (100) for a motor vehicle, comprising a refrigerant circuit (10) configured to circulate a refrigerant, the refrigerant circuit (10) comprising: - a main loop (A) comprising successively, according to the direction of refrigerant flow: — a compressor (7), — a first heat exchanger (1) thermally coupled with a first internal airflow (Fil) to a vehicle passenger compartment, — a first expansion valve (31), — a second heat exchanger (2) thermally coupled with an outside airflow (Fe) to the vehicle's passenger compartment, — a refrigerant fluid accumulation device (8), - a first branch (B) connecting a first connection point (11) located on the main loop (A) downstream of the first exchanger (1) and upstream of the first expansion valve (31) to a second connection point (12) located on the main loop (A) downstream of the second heat exchanger (2) and upstream of the storage device (8), the first branch (B) comprising successively a second expansion valve (32) and a third heat exchanger (3), - a second branch branch (C) connecting a third connection point (13) located on the main loop (A) downstream of the first exchanger (1) and upstream of the first connection point (11) to a fourth connection point (14) located on the main loop (A) downstream of the second connection point (12) and upstream of the storage device (8), the second branch branch (C) comprising successively a third expansion valve (33) and a fourth heat exchanger (4) thermally coupled with the first indoor airflow (Wire), - a third branch branch (D) connecting a fifth connection point (15) located on the main loop (A) downstream of the first exchanger (1) and upstream of the third connection point (13) to a sixth connection point (16) located on the main loop (A) downstream of the first connection point (11) and upstream of the first expansion valve (31).

2. Thermal conditioning system (100) according to claim 1, wherein the refrigerant circuit (10) comprises: - a first one-way valve (45) disposed on the main loop (A) between the fifth connection point (15) and the third connection point (13), the first one-way valve (45) being configured to allow refrigerant flow through the first one-way valve (45) only from the fifth connection point (15) to the third connection point (13), - a second one-way valve (46) disposed on the third branch (D) between the fifth connection point (15) and the sixth connection point (16),the second one-way valve (46) being configured to allow refrigerant fluid to circulate through the second one-way valve (46) only from the fifth connection point (15) to the sixth connection point (16).

3. Thermal conditioning system (100) according to claim 1 or 2, wherein the third heat exchanger (3) is thermally coupled with an element (25) of an electric drivetrain of a motor vehicle.

4. Thermal conditioning system (100) according to any one of the preceding claims, wherein the refrigerant circuit (10) comprises a fourth branch (E) connecting a seventh connection point (17) disposed on the main loop (A) downstream of the first exchanger (1) and upstream of the first connection point (11) to an eighth connection point (18) disposed on the second branch (C) downstream of the fourth exchanger (4) and upstream of the fourth connection point (14), the fourth branch (E) comprising successively a fourth expansion valve (34) and a fifth heat exchanger (5) configured to exchange heat with a second indoor airflow (Fi2).

5. Thermal conditioning system (100) according to any one of the preceding claims, wherein the refrigerant circuit (10) comprises a fifth branch (F) connecting a ninth connection point (19) disposed on the main loop (A) downstream of an outlet (7b) of the compressor (7) and upstream of the first heat exchanger (1) to a tenth connection point (20) arranged on the main loop (A) downstream of the second heat exchanger (2) and upstream of the accumulation device (8), the fifth branch (F) comprising a sixth expansion valve (36).

6. Thermal conditioning system (100) according to any one of the preceding claims, wherein the main loop (A) of the refrigerant circuit (10) includes an internal exchanger (6) configured to permit heat exchange between the refrigerant circulating between the first connection point (11) and the first expansion valve (31) and the refrigerant downstream of the storage device (8) and upstream of an inlet (7a) of the compressor (7).

7. Thermal conditioning system (100) according to any one of claims 1 to 6 in combination with claim 4, wherein the fourth bypass branch (E) comprises a fifth expansion valve (35) disposed downstream of the fifth heat exchanger (5).

8. Thermal conditioning system (100) according to the preceding claim, wherein the refrigerant circuit (10) includes a third one-way valve (47) disposed on the second branch branch (C) between the fourth heat exchanger (4) and the eighth connection point (18), the third one-way valve (47) being configured to permit refrigerant flow through the third one-way valve (47) from the fourth heat exchanger (4) to the eighth connection point (18), and being configured to prohibit refrigerant flow through the third one-way valve (47) from the eighth connection point (18) to the fourth heat exchanger (4).

9. A thermal conditioning system (100) according to any one of claims 1 to 6 in combination with claim 4, wherein the fourth branch (E) is devoid of an expansion valve between the fifth heat exchanger (5) and the eighth connection point (18), and wherein the refrigerant circuit (10) comprises a third one-way valve (47') disposed on the second branch (C) between the eighth connection point (18) and the fourth connection point (14), the third one-way valve (47') being configured to permit circulation of refrigerant fluid through the third one-way valve from the eighth connection point (18) to the fourth connection point (14), and being configured to prohibit circulation of refrigerant fluid through the third one-way valve (47') from the fourth connection point (14) to the eighth connection point (18).

10. A method of operating a thermal conditioning system (100) according to any one of the preceding claims, in a so-called dehumidification mode in which: - a first flow (Qr1) of refrigerant circulates in the compressor (7) where it passes through a high pressure, and circulates in the main loop (A), in the first heat exchanger (1) where it releases heat, and divides into: - a second flow (Qr2) circulating in the main loop (A), then in the second bypass branch (C), successively in the third expansion valve (33) where it undergoes expansion and passes through a low pressure lower than the high pressure, in the fourth heat exchanger (4) where it receives heat, and - a third flow (Qr3) circulating in the third bypass branch (D), then in the main loop (A), successively in the first expansion valve (31) where it undergoes expansion and passes through a low pressure, in the second heat exchanger (2) where it receives heat heat,and joins the refrigerant flow from the fourth heat exchanger (4), the total flow (Qrl) formed circulates in the accumulation device (8) and returns to the compressor (7).

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