Thermal conditioning system

Abstract

The invention relates to a thermal conditioning system (100) for a motor vehicle, comprising a refrigerant circuit (10) including: - A main loop (A) comprising successively: - a compressor (7), - a first heat exchanger (1) thermally coupled with an interior airflow (Fi) to a vehicle passenger compartment, - a first one-way valve (43), - a first expansion valve (31), - a second heat exchanger (2) configured to exchange heat with an exterior airflow (Fe) to the vehicle passenger compartment, - a refrigerant accumulation device (8), - A first branch (B) of the main loop (A), comprising a second expansion valve (32), - A second branch (C) of the main loop (A), comprising a third expansion valve (33) and a third heat exchanger (3).- A third branch (D) comprising successively a fourth expansion valve (34) and a fourth heat exchanger (4) configured to exchange heat with the internal airflow (Fi). Figure 1,

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 GWP of one, can be used as a refrigerant. To optimize energy efficiency, it is useful to have multiple operating modes to make the best use of the various available heat sources. It is generally necessary to implement a large number of shut-off valves and expansion valves on the refrigerant circuit, which increases the cost of the air conditioning system.

[0003] Furthermore, in the case of an electric vehicle, it may be necessary to be able to heat the battery, particularly to enable rapid charging in cold ambient temperatures, especially below freezing. Dedicated heating devices can be used. Such dedicated devices further increase the price and complexity of the heating system.

[0004] There is therefore a need for a cost-optimized thermal conditioning system that allows for heating the battery. 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 an airflow inside a vehicle's passenger compartment, — a first one-way valve, — a first pressure regulator, — a second heat exchanger configured to exchange heat 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 a compressor outlet and upstream of the first heat exchanger to a second connection point located on the main loop downstream of the second heat exchanger and upstream of the accumulation device, the first branch comprising a second expansion valve, - A second branch connecting a third connection point located on the main loop between the first exchanger and the first expansion valve to a fourth connection point located on the main loop downstream of the second exchanger and upstream of the accumulation device, the second branch successively comprising a third expansion valve and a third heat exchanger, - A third branch connecting a fifth connection point disposed on the main loop between the first one-way valve and the first expansion valve to a sixth connection point disposed on the main loop between the second connection point and the fourth connection point, the third branch comprising successively a fourth expansion valve and a fourth heat exchanger configured to exchange heat with the indoor airflow, in which the first one-way valve is configured to permit refrigerant flow from the fifth connection point to the third connection point and configured to prohibit refrigerant flow from the third connection point to the fifth connection point.

[0006] This circuit architecture allows heat to be transferred to the indoor airflow at the first heat exchanger, and heat to be selectively absorbed or transferred to the outdoor airflow at the second heat exchanger. The first one-way valve directs the refrigerant from the first heat exchanger to the third heat exchanger. Using a one-way valve instead of an expansion valve reduces the cost of the components in the thermal conditioning system.

[0007] The features listed in the following paragraphs can be implemented independently of each other or in any technically possible combination:

[0008] According to one embodiment of the thermal conditioning system, the first one-way valve is a non-return valve.

[0009] This type of component is particularly advantageous for reducing the cost of the thermal conditioning system, while allowing advantageous operating modes such as those where heating is carried out at the level of the third heat exchanger.

[0010] Alternatively, the first one-way valve may be an electrically operated valve.

[0011] According to one embodiment, the first heat exchanger is configured to exchange heat with an airflow inside a vehicle passenger compartment.

[0012] 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 configured to exchange heat with an airflow inside the vehicle's passenger compartment.

[0013] According to one embodiment of the thermal conditioning system, the main loop includes an internal exchanger configured to allow heat exchange between the refrigerant circulating between the fifth connection point and the first expansion valve and the refrigerant downstream of the accumulation device and upstream of a compressor inlet.

[0014] The internal heat exchanger includes a first heat exchange section arranged on the main loop between the first expansion valve and the fifth connection point, and a second heat exchange section arranged on the main loop downstream of the accumulator and upstream of the compressor inlet.

[0015] 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.

[0016] The first heat exchange section arranged on the main loop between the tenth connection point and the fifth connection point.

[0017] According to one embodiment, the third heat exchanger is thermally coupled with an element of an electric traction chain of a motor vehicle.

[0018] The third heat exchanger allows the element of the vehicle's electric powertrain to be selectively cooled or heated.

[0019] According to one embodiment, the element of the vehicle's electric powertrain includes an electrical energy storage battery.

[0020] Alternatively or in addition, the element of the vehicle's electric drive chain includes an electric vehicle traction motor.

[0021] 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.

[0022] 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.

[0023] According to one embodiment, the thermal conditioning system includes a fourth branch connecting a seventh connection point located on the main loop downstream of the first connection point and upstream of the first exchanger to an eighth connection point located on the second branch downstream of the third expansion valve and upstream of the fourth connection point, the fourth branch including a fifth expansion valve.

[0024] The fourth bypass branch allows the high-pressure, high-temperature refrigerant from the compressor outlet to reach the third heat exchanger without passing through the first or second heat exchangers. The flow circulating in the fourth bypass branch increases the total refrigerant flow rate supplied by the compressor and thus increases the heating power provided by the refrigerant.

[0025] The first regulator is, for example, an electronic regulator. Similarly, the second regulator, the third regulator, the fourth regulator and the fifth regulator can be electronic regulators.

[0026] According to one embodiment, the thermal conditioning system includes a fifth branch connecting a ninth connection point located on the second branch downstream of the third exchanger and upstream of the fourth connection point to a tenth connection point located on the main loop between the fifth connection point and the first expansion valve.

[0027] The tenth connection point is arranged between the first expansion valve and the first heat exchange section of the internal exchanger.

[0028] The refrigerant circuit includes a second one-way valve located on the fifth branch. The second one-way valve is configured to allow refrigerant flow from the ninth connection point to the tenth connection point and configured to prohibit a refrigerant fluid circulation from the tenth connection point to the ninth connection point.

[0029] The fifth bypass branch allows the high-pressure or intermediate-pressure refrigerant from the third heat exchanger to rejoin the main loop and from there to the compressor inlet, passing first through either the second or the fourth heat exchanger. The fifth bypass branch thus allows the refrigerant to supply heat to the electric traction element at the third heat exchanger, thereby heating the electric traction element.

[0030] The second one-way valve is, for example, a non-return valve.

[0031] According to one embodiment of the thermal conditioning system, the second branch branch includes a sixth expansion valve disposed between the ninth connection point and the fourth connection point.

[0032] The sixth expansion valve allows the refrigerant from the third heat exchanger to expand before it mixes with the refrigerant from the fourth heat exchanger. The fourth heat exchanger can therefore operate at a higher pressure than the third heat exchanger, and thus with a higher evaporation temperature.

[0033] The refrigerant circuit may include a third one-way valve disposed on the main loop between the first exchanger and the third connection point.

[0034] The third one-way valve is configured to allow refrigerant flow from the first exchanger to the third connection point and configured to prohibit refrigerant flow from the third connection point to the first exchanger.

[0035] The third one-way valve is, for example, a non-return valve.

[0036] The refrigerant circuit may include a fourth valve unidirectional arranged on the main loop between the fourth interchange and the sixth connection point.

[0037] The fourth one-way valve is configured to allow refrigerant flow from the fourth exchanger to the sixth connection point and is configured to prohibit refrigerant flow from the sixth connection point to the fourth exchanger.

[0038] The fourth one-way valve is, for example, a non-return valve.

[0039] The main loop includes a first shut-off valve disposed between the first connection point and the first heat exchanger. More specifically, the first shut-off valve is located between the first connection point and the seventh connection point.

[0040] The main loop includes a second shut-off valve disposed between the second connection point and the sixth connection point.

[0041] The first shut-off valve is an electrically operated valve. The second shut-off valve is an electrically operated valve.

[0042] The first shut-off valve is a two-way valve. Similarly, the second shut-off valve is a two-way valve.

[0043] According to one embodiment, the thermal conditioning system includes a movable device configured to vary a passage section of the outside airflow to the second exchanger. The passage area can vary between a minimum and a maximum value. The minimum value can be zero, meaning that the moving device closes the air supply to the second exchanger.

[0044] The invention also relates to a method of operating a thermal conditioning system as described above, in a so-called passenger compartment cooling and battery cooling mode, in which: - a total flow of refrigerant circulates in the compressor where it passes through high pressure, and circulates in the first bypass branch, in the second heat exchanger where it transfers heat to the outside airflow, in the first expansion valve, in the internal heat exchanger and divides into: — a second flow circulating in the third bypass branch, successively in the fourth 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 from the internal airflow and — a third flow circulating in the main loop, in the first one-way valve, in the second bypass branch, successively in the third expansion valve where it undergoes expansion and passes to low pressure, in the third exchanger where it receives heat, and joins the refrigerant flow from the fourth exchanger, The total flow formed circulates in the main loop, successively in the accumulation device, in the internal exchanger, and returns to the compressor.

[0045] The invention also relates to a method of operating a thermal conditioning system as described above, in a so-called heat pump battery heating mode, in which: - A first flow of refrigerant circulates in the compressor where it passes under high pressure, and circulates in the main loop, and divides into: — a second flow circulating in the main loop, successively in the first exchanger, in the second bypass branch, in the third pressure regulator without undergoing any expansion, — a third flow circulating in the fourth branch of the bypass, in the fifth expansion valve without undergoing expansion, and rejoins the refrigerant coming from the third expansion valve, The total flow formed circulates through the third heat exchanger where it gives up heat, through the fifth bypass branch, through the main loop, successively through the first expansion valve where it undergoes expansion and passes to a low pressure lower than the high pressure, through the second exchanger where it receives heat from the outside airflow, through the accumulation device, through the internal exchanger, and returns to the compressor.

[0046] In this operating mode, the second flow of refrigerant can circulate in the first heat exchanger without transferring heat to the internal airflow. This refrigerant circulation prevents the accumulation of refrigerant and oil in the first heat exchanger. The high-pressure refrigerant circulating in the fourth branch of the bypass, as well as the high-pressure refrigerant from the first exchanger, both circulate in the third exchanger, which allows the traction chain element to be heated. The second exchanger operates as an evaporator, with the heat of vaporization being taken from the outside airflow. This operating mode is particularly suited to conditions of use in which a high heating power is desired, for example when the ambient temperature is cold, for example negative.

[0047] The invention also relates to a method of operating a thermal conditioning system as already described, in a so-called first mode of battery and passenger compartment heating, in which: - a total flow of refrigerant circulates in the compressor where it passes at high pressure, and circulates in the main loop, in the first exchanger, in the second bypass branch, successively in the third expansion valve where it undergoes expansion and passes to an intermediate pressure lower than the high pressure, in the third heat exchanger where it gives up heat, in the fifth bypass branch, in the main loop successively in the first expansion valve where it undergoes expansion and passes to a low pressure lower than the intermediate pressure, in the second exchanger where it receives heat from the outside airflow, in the accumulation device, in the internal exchanger, and returns to the compressor.

[0048] In this mode of operation, the entire high-pressure refrigerant circulates in the first exchanger, and the fourth branch of the bypass is not traversed by a flow of refrigerant. The high-pressure refrigerant heats the internal airflow at the first exchanger, undergoes expansion in the third expansion valve, and heats the traction chain element at the third exchanger. As with the previous operating mode, the second exchanger operates as an evaporator, with the heat of vaporization being taken from the outside airflow. This operating mode is particularly suited to conditions of use in which the need for heating power is moderate, for example when the ambient temperature is relatively high, around 10°C to 15°C.

[0049] The invention also relates to a method of operating a thermal conditioning system as described above, in a so-called second mode of battery and passenger compartment heating, in which: - A first flow of refrigerant circulates in the compressor where it passes under high pressure, and circulates in the main loop, and divides into: — a second flow circulating in the main loop, successively in the first exchanger, in the second bypass branch, in the third pressure regulator where it undergoes expansion and passes to a low pressure lower than the high pressure, — a third flow circulating in the fourth branch of the bypass, in the fifth expansion valve where it undergoes expansion and passes to a low pressure lower than the high pressure, and joins the refrigerant from the third expansion valve, the total flow formed circulates in the third heat exchanger where it gives up heat, in the fifth branch of the bypass, in the main loop, successively in the first expansion valve where it undergoes expansion and passes to a low pressure lower than the intermediate pressure, in the second exchanger where it receives heat from the outside air flow, in the accumulation device, in the internal exchanger, and returns to the compressor.

[0050] This mode of operation differs from the previous one in that the fourth branch of the bypass carries a flow of refrigerant. The intermediate-pressure refrigerant at the outlet of the fifth expansion valve joins the intermediate-pressure refrigerant coming from the third expansion valve. The condensing pressure in the first heat exchanger is higher than the condensing pressure in the third heat exchanger. The two heat exchangers are thus decoupled, meaning that the distribution of heating power can be controlled by the expansion rate achieved by the third and fifth expansion valves.

[0051] The invention also relates to a method of operating a thermal conditioning system as already described, in a so-called first battery heating mode, in which: - A first flow of refrigerant circulates in the compressor where it passes under high pressure, and circulates in the main loop, and divides into: — a second flow circulating in the main loop, successively in the first exchanger without releasing heat, in the second bypass branch, in the third expansion valve where it undergoes expansion and passes to a low pressure lower than the high pressure, — a third flow circulating in the fourth branch of the bypass, in the fifth expansion valve where it undergoes expansion and passes to low pressure, and rejoins the refrigerant coming from the third expansion valve, The total flow formed circulates in the third heat exchanger where it releases heat, then circulates successively in the second bypass branch, in the sixth expansion valve without undergoing expansion, in the accumulation device, in the internal exchanger, and returns to the compressor.

[0052] In this operating mode, the high-pressure, high-temperature refrigerant discharged by the compressor is expanded without any heat exchange. The low-pressure, high-temperature refrigerant heats the drive train element. Only the third heat exchanger performs heat exchange. As before, the circulation of refrigerant in the first heat exchanger prevents the accumulation of refrigerant and oil in that exchanger.

[0053] The invention also relates to a method of operating a thermal conditioning system as described above, in a so-called second battery heating mode, in which: - A first flow of refrigerant circulates in the compressor where it passes under high pressure, and circulates in the main loop, and divides into: — a second flow circulating in the main loop, successively in the first exchanger without releasing heat, in the second bypass branch, in the third expansion valve without undergoing expansion, — a third flow circulating in the fourth branch of the bypass, in the fifth expansion valve without undergoing expansion, and rejoins the refrigerant coming from the third expansion valve, The total flow formed circulates through the third heat exchanger where it releases heat, then circulates successively through the second bypass branch, through the sixth expansion valve where it undergoes expansion and passes to a low pressure lower than the high pressure, through the accumulation device, through the internal exchanger, and returns to the compressor.

[0054] This operating mode differs from the previous one in that the refrigerant flowing through the third heat exchanger is at high pressure. The refrigerant is expanded downstream of the third heat exchanger to complete the thermodynamic cycle. As before, only the third heat exchanger is thermally active. As with the so-called 'heat pump-based battery heating' mode and the 'first battery heating mode', the circulation of refrigerant in the first heat exchanger prevents the accumulation of refrigerant and oil in that exchanger.

[0055] The invention also relates to a method of operating a thermal conditioning system as described above, in a so-called third mode of battery and passenger compartment heating, in which: - A first flow of refrigerant circulates in the compressor where it passes under high pressure, and circulates in the main loop, and divides into: — a second flow circulating in the main loop, successively in the first exchanger where it releases heat, in the second bypass branch, in the third expansion valve without undergoing any expansion, — a third flow circulating in the fourth branch of the bypass, in the fifth expansion valve without undergoing expansion, and rejoins the refrigerant coming from the third expansion valve, The total flow formed circulates through the third heat exchanger where it releases heat, and circulates successively through the second bypass branch, through the sixth expansion valve where it undergoes expansion and passes to a low pressure lower than the high pressure, through the accumulation device, through the internal exchanger, and returns to the compressor.

[0056] This operating mode differs from the previous mode in that the high-pressure refrigerant performs a heat exchange at the first heat exchanger, and heats the interior airflow. The passenger compartment and the element are thus heated simultaneously.

[0057] The invention also relates to a method of operating a thermal conditioning system as described above, in a mode known as passenger compartment dehumidification and battery heating, in which: - a total flow of refrigerant circulates in the compressor where it passes through high pressure, and circulates in the main loop, in the first heat exchanger, in the second bypass branch, in the third expansion valve, in the third heat exchanger where it releases heat, in the fifth bypass branch, in the main loop, in the third bypass branch, in the fourth expansion valve where it undergoes expansion and passes through a low pressure lower than the high pressure, in the fourth heat exchanger where it receives heat from the airflow inside, in the accumulation device, in the internal exchanger, and returns to the compressor.

[0058] According to an example of implementation of this mode of operation, the refrigerant flows in the third expansion valve, undergoing expansion to an intermediate pressure lower than the high pressure, and undergoes in the fourth expansion valve an expansion from the intermediate pressure to the low pressure.

[0059] In this mode of operation, when the thermal conditioning system includes a movable device configured to vary a section of passage of the outside air flow to the second exchanger, the section of passage of the outside air flow over the second exchanger can be maintained at its minimum value.

[0060] Since the second exchanger is thermally inactive, it is possible to reduce the cross-section of the passage of the outside airflow, in order to reduce the aerodynamic drag of the vehicle.

[0061] According to a variant of this mode of operation, the refrigerant flows through the third expansion valve without undergoing expansion, and undergoes expansion from high pressure to low pressure in the fourth expansion valve.

[0062] The invention also relates to a computer program stored on a memory and configured to operate a thermal conditioning system as described above in an operating method described above. Brief description of the drawings

[0063] Other features, details and advantages will become apparent upon reading the detailed description below, and upon analysis of the accompanying drawings, on which:

[0064] [Fig-1] is a schematic view of a thermal conditioning system according to an embodiment of the invention,

[0065] [Fig.2] is a schematic view of a thermal conditioning system according to a variant of the embodiment of [Fig.1],

[0066] [Fig.3] is a schematic view of the thermal conditioning system of the [Fig.1], operating according to a first mode of operation, called passenger compartment cooling and battery cooling mode,

[0067] [Fig.4] is a schematic view of the thermal conditioning system of the [Fig.1], operating according to a second mode of operation, called battery heating mode by heat pump,

[0068] [Fig.5] is a schematic view of the thermal conditioning system of the [Fig.1], operating according to a third mode of operation, called the first mode of battery and passenger compartment heating,

[0069] [Fig.6] is a schematic view of the thermal conditioning system of the [Fig.1], operating according to a fourth mode of operation, called the second mode of battery and passenger compartment heating,

[0070] [Fig.7] is a schematic view of the thermal conditioning system of the [Fig. 1], operating according to a fifth mode of operation, called the first battery heating mode, as well as a sixth mode of operation, called the second battery heating mode,

[0071] [Fig.8] is a schematic view of the thermal conditioning system of the [Fig.1], operating according to a seventh mode of operation, called the third mode of battery and passenger compartment heating,

[0072] [Fig.9] is a schematic view of the thermal conditioning system of the [Fig.l], operating according to an eighth mode of operation, called passenger compartment dehumidification and battery heating mode. Description of the implementation methods

[0073] 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 a priority of one element or parameter over another, and the designations may be interchanged.

[0074] 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 that the first element is placed after the second element with respect to the direction of flow, or path, of the fluid in question. In the case of the 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..

[0075] 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.

[0076] When it is specified that a subsystem includes a given element, this does not exclude the presence of other elements in that subsystem.

[0077] The thermal conditioning system 100, which will be described below, comprises an electronic control unit 61 that receives information from various sensors measuring, in particular, the characteristics of the refrigerant at various points in the circuit. The electronic control unit 61 also receives instructions from the vehicle occupants, such as the desired temperature inside the passenger compartment. The electronic control unit 61 can also receive instructions from other electronic subsystems, such as the electrical energy storage battery management system. The electronic control unit 61 implements control laws to operate the various actuators in order to control the thermal conditioning system 100 and ensure compliance with the received instructions.

[0078] 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.

[0079] 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, i.e., 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 sections. branches of the refrigerant circuit, in order to ensure different modes of operation, as will be described later.

[0080] The refrigerant used by the refrigerant circuit 10 is here a natural fluid, such as R744. It is also possible to use a chemical refrigerant, such as R1234yf, or 134a.

[0081] 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.

[0082] The term "interior airflow Fi" refers to an airflow directed towards the passenger compartment of the motor vehicle. This interior airflow Fi may circulate within a heating, ventilation, and / or air conditioning (HVAC) system. This system is not shown in the various figures. A first fan-motor unit, not shown, is located within the HVAC system to increase the flow rate of the interior airflow Fi if necessary.

[0083] 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. A second motor-fan unit, also not shown, can be activated to increase the flow rate of the external airflow Fe if necessary. The airflow provided by both the first and second motor-fan units can be adjusted in real time according to heat exchange requirements, for example, by the electronic control unit 61 of the climate control system 100.

[0084] 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".

[0085] The heat transfer fluid circuit(s) also form one or more closed and sealed circuits in which a heat transfer fluid can circulate.

[0086] Figure [Fig.1] shows a thermal conditioning system 100 for a motor vehicle. The thermal conditioning system 100 includes a refrigerant circuit 10 configured to circulate a refrigerant. The refrigerant circuit 10 comprises a main loop A including successively, according to the direction of refrigerant flow: - a compressor 7, - a first heat exchanger 1 thermally coupled with an internal airflow Fi to a vehicle passenger compartment, - a first one-way valve 43, - a first regulator 31, - a second heat exchanger 2 configured to exchange heat with an outside airflow Fe to the vehicle's passenger compartment, - a refrigerant fluid accumulation device 8, The thermal conditioning system 100 includes a first branch B connecting a first connection point 11 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 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 including a second expansion valve 32, The thermal conditioning system 100 includes a second branch C connecting a third connection point 13 located on the main loop A between the first exchanger 1 and the first expansion valve 31 to a fourth connection point 14 located on the main loop A downstream of the second exchanger 2 and upstream of the storage device 8, the second branch C comprising successively a third expansion valve 33 and a third heat exchanger 3. The thermal conditioning system 100 includes a third branch branch D connecting a fifth connection point 15 arranged on the main loop A between the first one-way valve 43 and the first expansion valve 31 to a sixth connection point 16 arranged on the main loop A between the second connection point 12 and the fourth connection point 14, the third branch branch D comprising successively a fourth expansion valve 34 and a fourth heat exchanger 4 configured to exchange heat with the indoor airflow Fi. The first one-way valve 43 is configured to allow refrigerant flow from the fifth connection point 15 to the third connection point 13. The first one-way valve 43 is configured to prohibit refrigerant flow from the third connection point 13 to the fifth connection point 15. The refrigerant can thus flow through the first one-way valve only from the fifth connection point 15 to the third connection point 13. Reverse flow is blocked.

[0087] This circuit architecture allows heat to be transferred to the indoor airflow at the first heat exchanger 1, heat to be selectively absorbed or transferred to the outdoor airflow Fe at the second heat exchanger 2, and heat to be selectively absorbed or transferred at the second heat exchanger 3. The first one-way valve 43 directs the refrigerant from the first heat exchanger 1 to the third heat exchanger 3. The use of a one-way valve rather than an expansion valve reduces the cost of the components of the thermal conditioning system 100, while allowing the same main operating modes.

[0088] According to the illustrated example of the thermal conditioning system 100, the first one-way valve 43 is a non-return valve.

[0089] A non-return valve, a purely passive component requiring no electrical control, is particularly advantageous for reducing the cost of the thermal conditioning system, while allowing advantageous operating modes such as those where heating is carried out at the level of the third heat exchanger 3.

[0090] According to an unrepresented variant, the first one-way valve 43 may be an electrically operated valve. The valve is, for example, a two-position valve with stable equilibrium: either the valve is open and allows refrigerant to pass through, or the valve is closed and blocks the circulation of refrigerant. This type of component is simpler and less expensive than a pressure-reducing valve. Its use can therefore be advantageous for reducing costs compared to a system using an electronic pressure regulator instead.

[0091] The first exchanger 1 can receive high-pressure, high-temperature refrigerant fluid, discharged by the compressor 7 and coming from the compressor 7. The first exchanger 1 is configured to operate as a refrigerant fluid condenser. The first heat exchanger 1 thus allows the vehicle's passenger compartment to be heated.

[0092] Thermal coupling between the first heat exchanger 1 and the interior airflow Fi can be achieved in various ways.

[0093] According to one embodiment, illustrated in [Fig.1], the first heat exchanger 1 is configured to exchange heat with an interior airflow Fi to a passenger compartment of the vehicle. The thermal coupling between the first heat exchanger 1 and the internal airflow Fi is then said to be direct.

[0094] According to an alternative embodiment, illustrated in [Fig.2], the first heat exchanger 1 is configured to exchange heat with a heat transfer fluid circulating in a closed circuit 40 of heat transfer fluid. The heat transfer fluid circuit 40 includes a heat exchanger IA configured to exchange heat with an interior airflow Fi to the vehicle's passenger compartment. The thermal coupling between the first heat exchanger 1 and the internal airflow Fi is then said to be indirect, since it is achieved through a heat transfer fluid. The IA exchanger is called a heating radiator. The heat transfer fluid in circuit 40 can be, for example, a mixture of water and glycol. The first exchanger 1, or according to the variant concerned, the exchanger IA, is located in the heating, ventilation and / or air conditioning installation.

[0095] The second heat exchanger 2 is configured to operate selectively as a refrigerant condenser or as a refrigerant evaporator. Indeed, depending on the selected operating mode, the second heat exchanger 2 can receive either high-pressure, high-temperature refrigerant or low-pressure liquid refrigerant. The second interchange 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 moving forward.

[0096] The fourth heat exchanger 4 is configured to operate as a refrigerant fluid evaporator. Indeed, the fourth heat exchanger 4 can receive refrigerant in the form of a low-pressure liquid. The fourth heat exchanger 4 can cool the interior airflow Fi to the passenger compartment, so as to cool the passenger compartment. The fourth exchanger 4 is located in the heating, ventilation and / or air conditioning system. The fourth exchanger 4 is positioned upstream of the first exchanger 1 or of the exchanger IA according to a direction of flow of the internal air flow Fi.

[0097] According to the illustrated example, the main loop A includes an internal exchanger 6 configured to allow heat exchange between the refrigerant circulating between the fifth connection point 15 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.

[0098] The internal heat exchanger 6 comprises a first heat exchange section 6a arranged on the main loop A between the first expansion valve 31 and the fifth connection point 15, as well as a second exchange section thermal 6b arranged on the main loop A downstream of the accumulator 8 and upstream of the inlet 7a of the compressor 7.

[0099] 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.

[0100] The first heat exchange section 6a is arranged on the main loop A between the tenth connection point 20 and the fifth connection point 15.

[0101] According to the illustrated embodiment, the third heat exchanger 3 is thermally coupled with an element 25 of an electric traction chain of the motor vehicle.

[0102] The third exchanger 3 is configured to operate selectively as a refrigerant fluid condenser or as a refrigerant fluid evaporator. The third heat exchanger 3 thus allows the element 25 of the vehicle's electric traction chain to be selectively cooled or heated.

[0103] According to one embodiment, element 25 of the vehicle's electric drive chain includes an electrical energy storage battery. Alternatively or in addition, element 25 of the vehicle's electric drive chain includes an electric vehicle traction motor. Alternatively or in addition, element 25 of the vehicle's electric drive chain includes an electronic control unit for the vehicle's electric traction motor.

[0104] 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.

[0105] The thermal conditioning system 100 includes a fourth branch E connecting a seventh connection point 17 located on the main loop A downstream of the first connection point 11 and upstream of the first heat exchanger 1 to an eighth connection point 18 located on the second branch C downstream of the third expansion valve 33 and upstream of the fourth connection point 14. The fourth branch E includes a fifth expansion valve 35.

[0106] The fourth bypass branch E allows the high-pressure, high-temperature refrigerant fluid exiting the compressor 7 to reach the third heat exchanger 3 without passing through the first heat exchanger 1 or the second heat exchanger 2. The flow circulating in the fourth bypass branch E increases the total flow rate of refrigerant fluid supplied by compressor 7 and thus allows to increase the thermal heating power supplied by the refrigerant fluid.

[0107] The first regulator 31 is, for example, an electronic regulator. Similarly, the second regulator 32, the third regulator 33, the fourth regulator 34 and the fifth regulator 35 can be electronic regulators.

[0108] The thermal conditioning system 100 of the illustrated example includes a fifth branch F connecting a ninth connection point 19 located on the second branch C downstream of the third exchanger 3 and upstream of the fourth connection point 14 to a tenth connection point 20 located on the main loop A between the fifth connection point 15 and the first expansion valve 31.

[0109] The tenth connection point 20 is arranged between the first expansion valve 31 and the first heat exchange section 6a of the internal exchanger 6.

[0110] The refrigerant circuit 10 includes a set of one-way valves and shut-off valves for selecting the different portions of the circuit 10 in which the refrigerant can circulate, in order to operate the thermal conditioning system according to different operating modes.

[0111] The refrigerant fluid circuit 10 includes a second one-way valve 44 disposed on the fifth branch F. The second one-way valve 44 is configured to allow refrigerant flow from the ninth connection point 19 to the tenth connection point 20. The second one-way valve 44 is also configured to prohibit refrigerant flow from the tenth connection point 20 to the ninth connection point 19. The refrigerant can thus flow through the second one-way valve 44 only from the ninth connection point 19 to the tenth connection point 20. Circulation in the opposite direction is blocked.

[0112] The second one-way valve 44 is, for example, a non-return valve.

[0113] The fifth branch F allows the high-pressure or intermediate-pressure refrigerant fluid at the outlet of the third heat exchanger 3 to join the main loop A, and from there to the inlet 7a of the compressor 7, passing first either through the second heat exchanger 2 or through the fourth heat exchanger 4. The fifth branch F thus allows the refrigerant fluid to supply heat to the element 25 of the electric traction chain at the level of the third heat exchanger 3. Heating of the element 25 of the electric traction chain can thus be ensured.

[0114] According to the illustrated embodiment, the second branch of the bypass C includes a sixth regulator 36 disposed between the ninth connection point 19 and the fourth connection point 18. The sixth regulator 36 is, for example, an electronic regulator.

[0115] The sixth expansion valve 36 allows the refrigerant from the third heat exchanger 3 to expand before it joins the refrigerant from the fourth heat exchanger 4. The third heat exchanger 3 can therefore operate at a higher pressure than the fourth heat exchanger 4, and therefore with a higher evaporation temperature.

[0116] The refrigerant fluid circuit 10 may include a third one-way valve 45 disposed on the main loop A between the first exchanger 1 and the third connection point 13.

[0117] The third one-way valve 45 is configured to allow refrigerant flow from the first heat exchanger 1 to the third connection point 13 and configured to prohibit refrigerant flow from the third connection point 13 to the first heat exchanger 1. The refrigerant can thus flow through the third one-way valve 45 only from the outlet of the first heat exchanger 1 to the third connection point 13. Circulation in the main loop A in the opposite direction, from the third connection point 13 to the outlet 1b of the first heat exchanger 1, is blocked.

[0118] The third one-way valve 45 is, for example, a non-return valve.

[0119] The refrigerant circuit 10 includes a fourth one-way valve 46 located on the main loop A between the fourth interchange 4 and the sixth connection point 16.

[0120] The fourth one-way valve 46 is configured to allow refrigerant flow from the fourth heat exchanger 4 to the sixth connection point 16 and is configured to prohibit refrigerant flow from the sixth connection point 16 to the fourth heat exchanger 4. Refrigerant fluid circulation in the third branch of the bypass D can only occur from the fourth exchanger 4 to the sixth connection point 16.

[0121] The fourth one-way valve 46 is, for example, a non-return valve. The fourth one-way valve 46 prevents an accumulation of liquid refrigerant in the fourth exchanger 4, when the ambient temperature is cool and the fourth expansion valve 34 is in the closed position.

[0122] The main loop A includes a first shut-off valve 41 disposed between the first connection point 11 and the first heat exchanger 1. More specifically, the first shut-off valve 41 is located between the first connection point 11 and the seventh connection point 17.

[0123] The main loop A includes a second shut-off valve 42 disposed between the second connection point 12 and the sixth connection point 16.

[0124] The first shut-off valve 41 is an electrically operated valve. The second shut-off valve 42 is an electrically operated valve.

[0125] The first shut-off valve 41 is a two-way valve. Similarly, the second shut-off valve 42 is a two-way valve. The first shut-off valve 41 and the second shut-off valve 42 each have exactly one inlet and one outlet.

[0126] According to an embodiment illustrated in [Fig. 2], the thermal conditioning system 100 comprises a movable device 50 configured to vary a cross-sectional area of ​​the outside airflow Fe to the second heat exchanger 2. The mobile device 50 includes, for example, a set of movable shutters, a control mechanism capable of varying the position of the shutters, and an electric motor capable of actuating the control mechanism in order to vary the position of the shutters. The cross-section can vary between a minimum value and a maximum value. The minimum value can be zero, that is to say that the mobile device 50 closes the air supply on the second exchanger 2. The mobile device 50 makes it possible to reduce the aerodynamic drag of the vehicle when the thermal conditioning system operates in a mode in which the second exchanger 2 is thermally inactive.

[0127] Figures 3 to 9 illustrate the operation of the thermal conditioning system 100 of [Fig.1], according to different operating modes.

[0128] In these figures, the portions of the circuit 10 in which a flow of refrigerant circulates are shown as a thick solid line, while the portions in which the refrigerant does not circulate are shown as thin dashed lines. The different arrows indicate the direction of refrigerant flow in the different portions of the refrigerant circuit 10.

[0129] In steady state, the time variation of the mass of refrigerant in a heat exchanger is zero, and the flow rate of refrigerant downstream of a heat exchanger is equal to the flow rate of refrigerant upstream of this 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.

[0130] Fig. 3 illustrates a method of operation of the thermal conditioning system 100 in a mode known as passenger compartment cooling and battery cooling. In this operating mode, a total flow Qrl of refrigerant circulates in the compressor 7 where it passes through high pressure, and circulates in the first bypass branch B, in the second heat exchanger 2 where it releases heat to the outside airflow Fe, in the first expansion valve 31, in the internal heat exchanger 6 and divides into: - a second flow Qr2 circulating in the third bypass branch D, successively in the fourth expansion valve 34 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 from the inside airflow Fi, and - a third flow Qr3 circulating in the main loop A, in the first one-way valve 43, in the second branch of bypass C, successively in the third expansion valve 33 where it undergoes expansion and passes to low pressure, in the third exchanger 3 where it receives heat, and joins the flow of refrigerant fluid coming from the fourth exchanger 4. The total flow Qrl formed circulates in the main loop A, successively in the accumulation device 8, in the internal heat exchanger 6, and returns to the compressor 7.

[0131] In this mode of operation, the high-pressure, high-temperature refrigerant condenses in the second heat exchanger 2, the heat of condensation being dissipated into the outside airflow Fe. The refrigerant is then expanded in parallel by the third expansion valve 33 and by the fourth expansion valve 34, and passes to a low pressure. The low-pressure refrigerant evaporates partly in the third exchanger 3 and partly in the fourth exchanger 4. The internal airflow Fi and the traction chain element 25 are thus both cooled. The first exchanger 1 is not traversed by the refrigerant fluid and is thermally inactive.

[0132] The refrigerant fluid from the second exchanger 2 can pass through the first expansion valve 31 without undergoing expansion, or can undergo expansion and pass to an intermediate pressure lower than the high pressure. The efficiency of the internal heat exchanger 6 can be adjusted by changing the expansion rate achieved by the first expansion valve 31. Indeed, the expansion rate of the first expansion valve 31 allows the temperature of the high-pressure refrigerant circulating in the first heat exchange section 6a of the internal heat exchanger 6 to be varied. Consequently, the temperature of the low-pressure refrigerant coming from the second heat exchange section 6b of the internal heat exchanger 6 will also vary. For example, the inlet temperature in the compressor 7 can be controlled so as to remain below a maximum acceptable temperature, by adjusting the expansion rate of the first expansion valve 31.

[0133] The first shut-off valve 41 and the second shut-off valve 42 are in the closed position. The fifth pressure regulator 35 is in the closed position. The second one-way valve 44 prevents the refrigerant from flowing from the tenth connection point 10 to the ninth connection point 19 through the fifth branch F. The portion of the main loop A between the first connection point 11 and the third connection point 13 does not carry the refrigerant. Similarly, the refrigerant flow rate in the fourth branch E is zero.

[0134] Figure 4 illustrates a method of operation of the conditioning system thermal 100 in a so-called battery heating mode by heat pump. In this operating mode, an initial flow Qrl of refrigerant circulates through the compressor 7 where it is subjected to high pressure, and then circulates in the main loop A, where it splits into: - a second flow Qr2 circulating in the main loop A, successively in the first exchanger 1, in the second bypass branch C, in the third expansion valve 33 without undergoing expansion, - a third flow Qr3 circulating in the fourth branch of bypass E, in the fifth expansion valve 35 without undergoing expansion, and joins the refrigerant fluid coming from the third expansion valve 33. The total flow Qrl formed circulates in the third heat exchanger 3 where it gives up heat, in the fifth bypass branch F, in the main loop A, successively in the first expansion valve 31 where it undergoes expansion and passes to a lower pressure than the high pressure, in the second exchanger 2 where it receives heat from the outside air flow Fe, in the accumulation device 8, in the internal exchanger 6, and returns to the compressor 7.

[0135] In this operating mode, the second flow Qr2 of refrigerant can circulate in the first heat exchanger 1 without transferring heat to the internal airflow Fi. This circulation of refrigerant prevents an accumulation of refrigerant and oil in the first heat exchanger 1. For this purpose, a flap, not shown, can block the airflow over the first exchanger 1, which inhibits the heat exchange of the refrigerant. The high-pressure, high-temperature refrigerant circulating in the fourth branch of the bypass E, as well as the high-pressure refrigerant from the first heat exchanger 1, both circulate in the third heat exchanger 3, which allows to heat element 25 of the traction chain. The third exchanger 3 operates as a condenser. The second exchanger 2 operates as an evaporator, with the heat of vaporization being taken from the outside airflow Fe. This operating mode is particularly suited to conditions of use in which a high heating power is desired, for example when the ambient temperature is cold, for example negative.

[0136] The second regulator 32, the sixth regulator 36 and the fourth regulator 34 are all three in the closed position. The first shut-off valve 41 and the second shut-off valve 42 are in the open position. The third regulator 33 and the fifth regulator 35 are in the fully open position. The flow rate in the first branch of the bypass B is zero. The flow rate in the portion of the second branch of the bypass C between the ninth connection point 19 and the fourth connection point 14 is zero. The first one-way valve 43 prevents the refrigerant from circulating in the main loop A from the third connection point 13 to the tenth connection point 20. The seventh connection point 17 is a splitting point where the first flow Qrl of high-pressure refrigerant divides into a second flow Qr2 circulating in the main loop A towards the first heat exchanger 1 and a third flow Qr3 circulating in the fourth branch E towards the fifth expansion valve 35. The eighth connection point 18 is a regrouping point where the refrigerant from the outlet 33b of the third expansion valve 33 and the refrigerant from the fifth expansion valve 35 join. The two combined flows then enter the inlet 3a of the third heat exchanger 3. Internal heat exchanger 6 is thermally inactive, since the first heat exchange section 6a does not carry a flow of refrigerant. The fourth heat exchanger 4 is thermally inactive, because the third branch of the bypass D does not carry a flow of refrigerant. The direction of travel of the second exchanger 2, operating here as an evaporator, is reversed compared to the previous operating mode, in which the second exchanger 2 operates as a condenser.

[0137] According to a variant of this battery heating mode by heat pump, not shown, the entire first flow Qrl discharged by the compressor 7 circulates in the fourth branch of bypass E. In other words, the second flow rate Qr2 circulating in the main loop A is zero, and the third flow rate Qr3 is the same as the first flow rate Qrl.

[0138] According to this variant, a flow Qrl of refrigerant fluid circulates in the compressor 7 where it passes to high pressure, and circulates in the main loop A, then in the fourth branch of bypass E, in the fifth expansion valve 35 without undergoing expansion, in the third heat exchanger 3 where it gives up heat, in the fifth branch of bypass F, in the main loop A, successively in the first expansion valve 31 where it undergoes expansion and passes to a low pressure lower than the high pressure, in the second exchanger 2 where it receives heat from the outside air flow Fe, in the accumulation device 8, in the internal exchanger 6, and returns to the compressor 7.

[0139] At the seventh connection point 17, all the refrigerant fluid from the first shut-off valve 41 is directed to the fourth branch E.

[0140] Fig. 5 illustrates a method of operation of the thermal conditioning system 100 in a mode called first mode of battery heating and passenger compartment heating. In this mode of operation, a total flow Qr of refrigerant circulates in the compressor 7 where it passes to high pressure, and circulates in the main loop A, in the first exchanger 1, in the second branch of bypass C, successively in the third expansion valve 33 where it undergoes expansion and passes to an intermediate pressure lower than the high pressure, in the third heat exchanger 3 where it gives up heat, in the fifth branch of bypass F, in the main loop A successively in the first expansion valve 31 where it undergoes expansion and passes to a low pressure lower than the intermediate pressure, in the second exchanger 2 where it receives heat from the outside air flow Fe, in the storage device 8, in the internal exchanger 6, and returns to the compressor 7.

[0141] In this mode of operation, the entire high-pressure refrigerant flows through the first exchanger 1, and the fourth branch E is not traversed by a flow of refrigerant. The high-pressure refrigerant heats the internal airflow Fi at the first exchanger 1, undergoes partial expansion in the third expansion valve 33 and heats the traction chain element 25 at the third exchanger 3. The first exchanger 1 and the third exchanger 3 both operate as condensers. As with the previous operating mode, the second exchanger 2 operates as an evaporator, with the heat of vaporization being taken from the outside airflow Fe. This operating mode is particularly suited to conditions of use in which the heating power requirement is moderate, for example when the ambient temperature is relatively high, for example around 10°C to 15°C.

[0142] The second regulator 32, the fifth regulator 35, the sixth regulator 36 and the fourth regulator 34 are all four in the closed position. The first shut-off valve 41 and the second shut-off valve 42 are in the open position. The flow rate in the first branch B and the fourth branch E is zero. The flow rate in the portion of the second branch C between the ninth connection point 19 and the fourth connection point 14 is zero. The first one-way valve 43 prevents the refrigerant from circulating in the main loop A from the third connection point 13 to the tenth connection point 20; therefore, the flow rate is zero in this section. The refrigerant from outlet 1b of the first heat exchanger 1 is thus redirected, at the third connection point 13, to the second branch line C, in the direction of the third expansion valve 33. The internal exchanger 6 is thermally inactive, since the flow rate of refrigerant fluid in the first heat exchange section 6a is zero. The fourth exchanger 4 is thermally inactive, since the flow of refrigerant fluid in the third branch of bypass D is zero.

[0143] Fig. 6 illustrates a method of operation of the thermal conditioning system 100 in a so-called second mode of battery heating and passenger compartment heating. In this operating mode, an initial flow Qrl of refrigerant circulates through the compressor 7 where it is subjected to high pressure, and then circulates in the main loop A, where it splits into: - a second flow Qr2 circulating in the main loop A, successively in the first exchanger 1, in the second bypass branch C, in the third expansion valve 33 where it undergoes expansion and passes to an intermediate pressure lower than the high pressure, - a third flow Qr3 circulating in the fourth branch of bypass E, in the fifth expansion valve 35 where it undergoes expansion and passes to an intermediate pressure lower than the high pressure, and joins the refrigerant fluid coming from the third expansion valve 33. The total flow Qrl formed circulates in the third heat exchanger 3 where it releases heat, in the fifth bypass branch F, in the main loop A, successively in the first expansion valve 31 where it undergoes expansion and passes to a low pressure lower than the intermediate pressure, in the second heat exchanger 2 where It receives heat from the outside airflow Fe, in the accumulation device 8, in the internal exchanger 6, and returns to the compressor 7.

[0144] This operating mode differs from the previous one in that the fourth branch E carries a flow of refrigerant. The intermediate-pressure refrigerant at the outlet of the fifth expansion valve 35 joins the intermediate-pressure refrigerant from the outlet 33b of the third expansion valve 33. The condensing pressure in the first heat exchanger 1, equal to the high pressure, is higher than the condensing pressure in the third heat exchanger 3, equal to the intermediate pressure. The two heat exchangers 1, 3 are thus decoupled, meaning that the temperature of the refrigerant in the third heat exchanger 3 is independent of the temperature in the first heat exchanger 1. Furthermore, the distribution of heating power between these two heat exchangers 1, 3 can be controlled by adjusting the expansion ratio achieved by the third expansion valve 33 and the fifth expansion valve 35.

[0145] The first flow Qrl of high-pressure refrigerant is divided at the seventh connection point 17 into a second flow Qr2 circulating in the main loop A towards the first exchanger 1 and a third flow Qr3 circulating in the fourth branch E towards the fifth expansion valve 35. The refrigerant from the third expansion valve 33 and the refrigerant from the fifth expansion valve 35 meet at the eighth connection point 18, the flow formed being in steady state identical to the flow upstream of the seventh connection point 17, and therefore corresponding to the first flow Qrl.

[0146] The circulation in the rest of circuit 10 is identical to the previous operating mode.

[0147] Fig. 7 illustrates a method of operation of the thermal conditioning system 100 in a mode called first battery heating mode. In this operating mode, an initial flow Qrl of refrigerant circulates through the compressor 7 where it is subjected to high pressure, and then circulates in the main loop A, where it splits into: - a second flow Qr2 circulating in the main loop A, successively in the first exchanger 1 without releasing heat, in the second bypass branch C, in the third expansion valve 33 where it undergoes expansion and passes to a low pressure lower than the high pressure, - a third flow Qr3 circulating in the fourth branch of bypass E, in the fifth expansion valve 35 where it undergoes expansion and passes to low pressure, and joins the refrigerant fluid coming from the third expansion valve 33. The total flow Qrl formed circulates in the third heat exchanger 3 where it releases heat, then circulates successively in the second bypass branch C, in the sixth expansion valve 36 without undergoing expansion, in the accumulation device 8, in the internal exchanger 6, and returns to the compressor 7.

[0148] In this operating mode, the high-pressure, high-temperature refrigerant discharged by the compressor 7 is expanded without any heat exchange. The low-pressure, high-temperature refrigerant heats the traction chain element 25. Of the various heat exchangers, only the third exchanger 3 performs heat exchange. As before, the circulation of refrigerant fluid in the first exchanger 1 prevents an accumulation of refrigerant fluid and oil in this exchanger 1.

[0149] The first expansion valve 31, the second expansion valve 32 and the fourth expansion valve 34 are all four in the closed position. The third regulator 33 and the fifth regulator 35 are in the partially open position. The sixth regulator 36 is in the maximum open position. The first shut-off valve 41 is in the open position. The second shut-off valve 42 is in the closed position. The flow rate in the first branch B and the third branch D is zero. The flow rate in the portion of the main loop A between the third connection point 13 and the fourth connection point 14 is zero. The first one-way valve 43 and the second one-way valve 44 prevent the refrigerant from the first heat exchanger 1 from circulating in the main loop A from the third connection point 13 to the tenth connection point 20, and then in the fifth branch F to the ninth connection point 19. The indoor air flow Fi is zero, so as to inhibit the heat exchange between the refrigerant and the indoor air flow Fi at the level of the first exchanger 1. A damper can for example block the indoor air flow Fi.

[0150] According to a variant of this mode called first battery heating mode, not shown, the entire first flow Qrl discharged by the compressor 7 circulates in the fourth branch of bypass E. In other words, the second flow rate Qr2 circulating in the main loop A is zero, and the third flow rate Qr3 is the same as the first flow rate Qrl.

[0151] According to this embodiment, a first flow Qrl of refrigerant circulates in the compressor 7 where it passes through high pressure, circulates in the main loop A, then in the fourth bypass branch E, in the fifth expansion valve 35 where it undergoes expansion and passes through low pressure, in the third heat exchanger 3 where it releases heat, in the second bypass branch C, in the sixth expansion valve 36 without undergoing expansion, in the accumulation device 8, in the internal exchanger 6, and returns to the compressor 7.

[0152] At the seventh connection point 17, all the refrigerant fluid from the first shut-off valve 41 is directed to the fourth branch E.

[0153] Fig. 7 also illustrates a method of operating the thermal conditioning system 100 in a so-called second battery heating mode. In this operating mode, an initial flow Qrl of refrigerant circulates through the compressor 7 where it is subjected to high pressure, and then circulates in the main loop A, where it splits into: - a second flow Qr2 circulating in the main loop A, successively in the first exchanger 1 without releasing heat, in the second bypass branch C, in the third expansion valve 33 without undergoing expansion, - a third flow Qr3 circulating in the fourth branch of bypass E, in the fifth expansion valve 35 without undergoing expansion, and joins the refrigerant fluid coming from the third expansion valve 33. The total flow Qrl formed circulates in the third heat exchanger 3 where it gives up heat, then circulates successively in the second bypass branch C, in the sixth expansion valve 36 where it undergoes expansion and passes to a lower pressure than the high pressure, in the accumulation device 8, in the internal exchanger 6, and returns to the compressor 7.

[0154] This operating mode differs from the previous one in that the refrigerant flowing through the third heat exchanger 3 is at high pressure. The refrigerant is expanded downstream of the third heat exchanger 3 in order to close the thermodynamic cycle. As in the previous operating mode, only the third heat exchanger 3 is thermally active. As with the so-called 'battery heating by heat pump' mode and the so-called 'first battery heating mode' mode, the circulation of refrigerant fluid in the first exchanger 1 prevents an accumulation of refrigerant fluid and oil in this exchanger 1.

[0155] The circuit portions 10 in which the refrigerant circulates are identical to the previous operating mode. This mode of operation differs from the previous one by the control carried out on the regulators 33, 35, 36. In this operating mode, the third regulator 33 and the fifth regulator 35 are in the fully open position. The sixth regulator 36 is in the partially open position.

[0156] According to a variant of this so-called second battery heating mode, not shown, the entire first flow Qrl discharged by the compressor 7 circulates in the fourth branch of bypass E. In other words, the second flow rate Qr2 circulating in the main loop A is zero, and the third flow rate Qr3 is the same as the first flow rate Qrl.

[0157] According to this variant, a first flow Qrl of refrigerant fluid circulates in the compressor 7 where it passes to high pressure, and circulates in the main loop A, then in the fourth branch of bypass E, in the fifth expansion valve 35 without undergoing expansion, in the third heat exchanger 3 where it gives up heat, in the second branch of bypass C, in the sixth expansion valve 36 where it undergoes expansion and passes to a low pressure lower than the high pressure, in the accumulation device 8, in the internal exchanger 6, and returns to the compressor 7.

[0158] At the seventh connection point 17, all the refrigerant fluid from the first shut-off valve 41 is directed to the fourth branch E.

[0159] Fig. 8 illustrates a method of operation of the thermal conditioning system 100 in a so-called third mode of battery heating and passenger compartment heating. In this operating mode, an initial flow Qrl of refrigerant circulates through the compressor 7 where it is subjected to high pressure, and then circulates in the main loop A, where it splits into: - a second flow Qr2 circulating in the main loop A, successively in the first exchanger 1 where it releases heat, in the second bypass branch C, in the third expansion valve 33 without undergoing expansion, - a third flow Qr3 circulating in the fourth branch of bypass E, in the fifth expansion valve 35 without undergoing expansion, and joins the refrigerant fluid coming from the third expansion valve 33. The total flow Qrl formed circulates in the third heat exchanger 3 where it gives up heat, and circulates successively in the second bypass branch C, in the sixth expansion valve 36 where it undergoes expansion and passes to a low pressure lower than the high pressure, in the accumulation device 8, in the internal exchanger 6, and returns to the compressor 7.

[0160] This mode of operation differs from the previous mode in that the high-pressure refrigerant fluid performs a heat exchange at the level of the first exchanger 1, and heats the internal airflow Fi. The passenger compartment and element 25 are thus heated together. For this, the internal airflow Fi can exchange heat with the refrigerant fluid at the level of the first exchanger 1.

[0161] The refrigerant circulation is identical to that of the previous operating mode.

[0162] Figure 9 illustrates a method of operation of the conditioning system thermal 100 in a mode called passenger compartment dehumidification and battery heating. In this operating mode, a total flow Qr of refrigerant circulates in the compressor 7 where it passes to high pressure, and circulates in the main loop A, in the first exchanger 1, in the second branch of bypass C, in the third expansion valve 33, in the third heat exchanger 3 where it gives up heat, in the fifth branch of bypass F, in the main loop A, in the third branch of bypass D, in the fourth expansion valve 34 where it undergoes expansion and passes to a low pressure lower than the high pressure, in the fourth exchanger 4 where it receives heat from the interior airflow Fi, in the storage device 8, in the internal exchanger 6, and returns to the compressor 7.

[0163] According to an example of implementation of this mode of operation, the refrigerant flows in the third expansion valve 33 undergoing expansion to an intermediate pressure lower than the high pressure, and undergoes in the fourth expansion valve 34 an expansion from the intermediate pressure to the low pressure.

[0164] The first exchanger 1 and the third exchanger 3 both operate as condensers. The fourth exchanger 4 operates as an evaporator. The second exchanger 2 is thermally inactive. The first heat exchange section 6a and the second heat exchange section 6b of the internal heat exchanger are both traversed by the refrigerant; the internal heat exchanger 6 is therefore active and performs heat exchange. The interior airflow Fi is cooled at the fourth heat exchanger 4 and heated at the first heat exchanger 1. The vehicle's passenger compartment is thus dehumidified. Part of the heat taken from the internal airflow Fi at the level of the fourth exchanger 1 is rejected into the element 25 of the transmission chain at the level of the third exchanger 3.

[0165] In this mode of operation, when the thermal conditioning system 100 includes a movable device 50 configured to vary a passage section of the outside air flow Fe to the second exchanger 2, the passage section of the outside air flow Fe over the second exchanger 2 can be maintained at its minimum value.

[0166] Since the second exchanger 2 is thermally inactive, it is possible to reduce the cross-section of the passage of the outside airflow, in order to reduce the aerodynamic drag of the vehicle.

[0167] According to another example of implementation of this mode of operation, the refrigerant flows in the third expansion valve 33 without undergoing expansion, and undergoes in the fourth expansion valve 34 an expansion from high pressure to low pressure.

[0168] Many other modes of operation are of course possible with the proposed circuit architecture 10.

[0169] The invention also relates to a computer program stored in memory and configured to operate a thermal conditioning system 100 as described above, in an operating method described above. The memory can be integrated into the electronic control unit 61 of the thermal conditioning system 100. Memory contains program instructions, coded according to a programming language.

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 an interior airflow (Fi) to a vehicle passenger compartment, — a first one-way valve (43), — a first expansion valve (31), — a second heat exchanger (2) configured to exchange heat 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 an outlet (7b) of the compressor (7) and upstream of the first heat exchanger (1) 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 a second expansion valve (32), - A second branch (C) connecting a third connection point (13) located on the main loop (A) between the first heat exchanger (1) and the first expansion valve (31) to a fourth connection point (14) located on the main loop (A) downstream of the second heat exchanger (2) and upstream of the storage device (8), the second branch (C) comprising successively a third expansion valve (33) and a third heat exchanger (3), - A third branch branch (D) connecting a fifth connection point (15) located on the main loop (A) between the first one-way valve (43) and the first pressure regulator (31) to a sixth connection point (16) located on the main loop (A) between the second connection point (12) and the fourth connection point (14), the third branch of bypass (D) comprising successively a fourth expansion valve (34) and a fourth heat exchanger (4) configured to exchange heat with the indoor airflow (Fi), in which the first one-way valve (43) is configured to permit refrigerant flow from the fifth connection point (15) to the third connection point (13) and configured to prohibit refrigerant flow from the third connection point (13) to the fifth connection point (15).

2. Thermal conditioning system (100) according to claim 1, wherein the first one-way valve (43) is a check valve.

3. Thermal conditioning system (100) according to claim 1 or 2, wherein the main loop (A) includes an internal exchanger (6) configured to permit heat exchange between the refrigerant circulating between the fifth connection point (15) 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).

4. Thermal conditioning system (100) according to any one of the preceding claims, wherein the third heat exchanger (3) is thermally coupled with an element (25) of an electric drivetrain of a motor vehicle.

5. Thermal conditioning system (100) according to any one of the preceding claims, comprising a fourth branch (E) connecting a seventh connection point (17) disposed on the main loop (A) downstream of the first connection point (11) and upstream of the first heat exchanger (1) to an eighth connection point (18) disposed on the second branch (C) downstream of the third expansion valve (33) and upstream of the fourth connection point (14), the fourth branch (E) comprising a fifth expansion valve (35).

6. Thermal conditioning system (100) according to any one of the preceding claims, comprising a fifth branch (F) connecting to a ninth connection point (19) disposed on the second branch (C) downstream of the third heat exchanger (3) and upstream of the fourth connection point (19). connection (14) to a tenth connection point (20) disposed on the main loop (A) between the fifth connection point (15) and the first expansion valve (31), in which the refrigerant circuit (10) includes a second one-way valve (44) disposed on the fifth branch (F), the second one-way valve (44) being configured to permit refrigerant flow from the ninth connection point (19) to the tenth connection point (20) and configured to prohibit refrigerant flow from the tenth connection point (20) to the ninth connection point (19).

7. Thermal conditioning system (100) according to the preceding claim, wherein the second branch of bypass (C) comprises a sixth expansion valve (36) disposed between the ninth connection point (19) and the fourth connection point (14).

8. A method of operating a thermal conditioning system (100) according to any one of claims 1 to 7, in a so-called passenger compartment cooling and battery cooling mode in which: - a total flow (Qrl) of refrigerant circulates in the compressor (7) where it passes through a high pressure, and circulates in the first bypass branch (B), in the second heat exchanger (2) where it releases heat to the outside airflow (Fe), in the first expansion valve (31), in the internal heat exchanger (6) and divides into: — a second flow (Qr2) circulating in the third bypass branch (D), successively in the fourth expansion valve (34) 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 from the inside airflow (Fi), and — a third flow (Qr3) circulating in the main loop (A), in the first one-way valve (43),in the second bypass branch (C), successively in the third expansion valve (33) where it undergoes expansion and passes to low pressure, in the third heat exchanger (3) where it receives heat, and joins the refrigerant flow from the fourth heat exchanger (4), the total flow (Qrl) formed circulates in the main loop (A), successively in the accumulation device (8), in the internal heat exchanger (6), and returns to the compressor (7).

9. A method of operating a thermal conditioning system (100) according to any one of claims 1 to 7 in combination with claims 5 and 6, in a so-called heat pump battery heating mode in which: - a first flow (Qrl) of refrigerant circulates in the compressor (7) where it is under high pressure, and circulates in the main loop (A), and divides into: - a second flow (Qr2) circulating in the main loop (A), successively in the first heat exchanger (1), in the second bypass branch (C), in the third expansion valve (33) without undergoing expansion, - a third flow (Qr3) circulating in the fourth bypass branch (E), in the fifth expansion valve (35) without undergoing expansion, and rejoins the refrigerant from the third expansion valve (33), the total flow (Qrl) formed circulates in the third heat exchanger (3) where it releases heat, in the fifth branch derivation (F),in the main loop (A), successively in the first expansion valve (31) where it undergoes expansion and passes to a low pressure lower than the high pressure, in the second heat exchanger (2) where it receives heat from the outside airflow (Fe), in the accumulation device (8), in the internal heat exchanger (6), and returns to the compressor (7).

10. A method of operating a thermal conditioning system (100) according to any one of claims 1 to 7 in combination with claim 6, in a mode called first mode of battery heating and passenger compartment heating in which: - a total flow (Qr) 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), in the second bypass branch (C), successively in the third expansion valve (33) where it undergoes expansion and passes through an intermediate pressure lower than the high pressure, in the third heat exchanger (3) where it releases heat, in the fifth bypass branch (F), in the main loop (A) successively in the first expansion valve (31) where it undergoes expansion and passes through a low pressure lower than the intermediate pressure, in the second heat exchanger (2) where it receives heat from the outside airflow (Fe),within the system, accumulation (8), in the internal exchanger (6), and returns to the compressor (7).

11. A method of operating a thermal conditioning system (100) according to any one of claims 1 to 7 in combination with claim 5, in a so-called second mode of battery and passenger compartment heating in which: - a first flow (Qrl) of refrigerant circulates in the compressor (7) where it passes through a high pressure, and circulates in the main loop (A), and divides into: — a second flow (Qr2) circulating in the main loop (A), successively in the first exchanger (1), in the second bypass branch (C), in the third pressure reducer (33) where it undergoes expansion and passes to a low pressure lower than the high pressure, — a third flow (Qr3) circulating in the fourth branch of bypass (E), in the fifth expansion valve (35) where it undergoes expansion and passes to a low pressure lower than the high pressure, and joins the refrigerant from the third expansion valve (33), the total flow (Qrl) formed circulates in the third heat exchanger (3) where it gives up heat, in the fifth branch of bypass (F), in the main loop (A), successively in the first expansion valve (31) where it undergoes expansion and passes to a low pressure lower than the intermediate pressure, in the second exchanger (2) where it receives heat from the outside air flow (Fe), in the accumulation device (8), in the internal exchanger (6), and returns to the compressor (7).

12. A method of operating a thermal conditioning system (100) according to any one of claims 1 to 7 in combination with claim 5, in a so-called first battery heating mode in which: - a first flow (Qrl) of refrigerant circulates in the compressor (7) where it passes under high pressure, and circulates in the main loop (A), and divides into: — a second flow (Qr2) circulating in the main loop (A), successively in the first exchanger (1) without releasing heat, in the second bypass branch (C), in the third expansion valve (33) where it undergoes expansion and passes to a low pressure lower than the high pressure, — a third flow (Qr3) circulating in the fourth branch of bypass (E), in the fifth expansion valve (35) where it undergoes expansion and passes to low pressure, and joins the refrigerant from the third expansion valve (33), the total flow (Qrl) formed circulates in the third heat exchanger (3) where it gives up heat, then circulates successively in the second branch of bypass (C), in the sixth expansion valve (36) without undergoing expansion, in the accumulation device (8), in the internal exchanger (6), and returns to the compressor (7).

13. A method of operating a thermal conditioning system (100) according to any one of claims 1 to 7 in combination with claim 5, in a so-called second battery heating mode in which: - a first flow (Qrl) of refrigerant circulates in the compressor (7) where it passes under high pressure, and circulates in the main loop (A), and divides into: — a second flow (Qr2) circulating in the main loop (A), successively in the first exchanger (1) without releasing heat, in the second bypass branch (C), in the third expansion valve (33) without undergoing expansion, — a third flow (Qr3) circulating in the fourth bypass branch (E), in the fifth expansion valve (35) without undergoing expansion, and joins the refrigerant fluid coming from the third expansion valve (33), The total flow (Qrl) formed circulates in the third heat exchanger (3) where it gives up heat, then circulates successively in the second bypass branch (C), in the sixth expansion valve (36) where it undergoes expansion and passes to a lower pressure than the high pressure, in the accumulation device (8), in the internal exchanger (6), and returns to the compressor (7).

14. A method of operating a thermal conditioning system (100) according to any one of claims 1 to 7 in combination with claim 5, in a so-called third mode of battery and passenger compartment heating in which: - a first flow (Qrl) of refrigerant circulates in the compressor (7) where it passes through a high pressure, and circulates in the main loop (A), and divides into: — a second flow (Qr2) circulating in the main loop (A), successively in the first exchanger (1) where it gives up heat, in the second bypass branch (C), in the third expansion valve (33) without undergoing expansion, — a third flow (Qr3) circulating in the fourth bypass branch (E), in the fifth expansion valve (35) without undergoing expansion, and joins the refrigerant from the third expansion valve (33), the total flow (Qrl) formed circulates in the third heat exchanger (3) where it gives up heat, and circulates successively in the second bypass branch (C), in the sixth expansion valve (36) where it undergoes expansion and passes to a low pressure lower than the high pressure, in the accumulation device (8), in the internal exchanger (6), and returns to the compressor (7).

15. A method of operating a thermal conditioning system (100) according to any one of claims 1 to 7 in combination with claim 6, in a mode known as passenger compartment dehumidification and battery heating in which: - a total flow (Qr) of refrigerant circulates in the compressor (7) where it passes through high pressure, and circulates in the main loop (A), in the first exchanger (1), in the second bypass branch (C), in the third expansion valve (33), in the third heat exchanger (3) where it releases heat, in the fifth bypass branch (F), in the main loop (A), in the third bypass branch (D), in the fourth expansion valve (34) where it undergoes expansion and passes through a low pressure lower than the high pressure, in the fourth exchanger (4) where it receives heat from the interior airflow (Fi), in the accumulation device (8), in the internal exchanger (6),and returns to the compressor (7).

16. Computer program stored in memory and configured to operate a thermal conditioning system (100) according to any one of claims 1 to 7 in an operating method according to any one of claims 8 to 15.

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