Thermal conditioning system

Abstract

Thermal conditioning system (100) for a motor vehicle, including a refrigerant circuit (10) comprising: • - a main loop (A) comprising, successively: • -- a compressor (6), • -- a first heat exchanger (1) configured to exchange heat with a first heat transfer fluid (F1), • -- a first expansion valve (31), • -- a first refrigerant accumulation device (8), • -- a second expansion valve (32), • -- a second heat exchanger (2), • - a first bypass branch (B) comprising a third expansion valve (33) and a third heat exchanger (3), • - a second bypass branch (C) connecting the main loop (A) and the first bypass branch (B), • - a third bypass branch (D) connecting the main loop (A) and the first bypass branch (B), • - a fourth bypass branch (E) allowing the refrigerant leaving the compressor (6) to join the main loop (A), without passing through the first exchanger (1) and the second expansion valve (32), the fourth bypass branch (E) comprising a fourth expansion valve (34).

Description

Description Title: Thermal conditioning system Technical field [1] The present invention relates to the field of thermal conditioning systems. Such systems can, for example, be fitted to motor vehicles. These systems make it possible to ensure thermal regulation of various components, such as, for example, the passenger compartment or an electrical energy storage battery, when the vehicle is electrically powered. Heat exchanges are managed mainly by the compression and expansion of a refrigerant circulating in a circuit in which several heat exchangers are arranged. A compressor makes it possible to pass the refrigerant at high pressure and circulate it in the circuit. Prior art [2] The refrigerant circuit usually comprises a main loop and several branch branches which allow multiple combinations of refrigerant circulation to be achieved. Many operating modes can thus be obtained, such as cooling the air in the passenger compartment, heating the air in the passenger compartment, dehumidification of the air in the passenger compartment, regulation of the temperature of the vehicle batteries, or even recovery of the energy dissipated by these batteries, in order to heat the passenger compartment. [3] In order to optimize the thermodynamic performance of the thermal conditioning system, it is known to add an additional heating device in order to have sufficient heating power when the ambient temperature is particularly cold, for example negative. It is also common to install an exchanger to ensure sub-cooling of the refrigerant fluid in order to improve the available cooling power. However, the addition of these components also has the effect of increasing the complexity of the system, as well as its cost and weight. [4] There is therefore a need for thermal conditioning systems with improved performance without requiring specific devices such as an additional heating device. Summary [5] To this end, the present invention provides a thermal conditioning system for a motor vehicle, comprising a refrigerant circuit configured to circulate a refrigerant, the refrigerant circuit comprising: A main loop comprising successively according to the direction of circulation of the refrigerant fluid: -- a compressor, -- a first heat exchanger configured to exchange heat with a first heat transfer fluid, -- a first regulator, -- a first refrigerant fluid accumulation device, -- a second regulator, -- a second heat exchanger, A first bypass branch connecting a first connection point arranged on the main loop between the first refrigerant accumulation device and the second expansion valve to a second connection point arranged on the main loop between the second heat exchanger and an inlet of the compressor, the first bypass branch comprising a third expansion valve and a third heat exchanger, - A second bypass branch connecting a third connection point arranged on the main loop between the first expansion valve and the first refrigerant fluid accumulation device to a fourth connection point arranged on the first bypass branch between the first connection point and the third expansion valve, - A third branch connecting a fifth connection point arranged on the main loop between the first regulator and the third connection point to a sixth connection point arranged on the first branch bypass between the third heat exchanger and the second connection point, - A fourth bypass branch connecting a seventh connection point arranged on the main loop between an outlet of the compressor and the first heat exchanger to an eighth connection point arranged on the main loop between the second expansion valve and the second connection point, the fourth bypass branch comprising a fourth expansion valve. [6] This refrigerant circuit architecture makes it possible to obtain numerous operating modes, in particular allowing heating of the first heat transfer fluid at the first exchanger from heat recovered at the second exchanger or the third exchanger. The fourth branch branch also makes it possible to increase the flow rate of refrigerant circulating in the circuit and hence the thermal power supplied to the refrigerant. Compared to traditional architectures, this architecture makes it possible to do without an additional heating device and a subcooling exchanger. [7] The features listed in the following paragraphs can be implemented independently of each other or in any technically possible combination: [8] According to one aspect of the thermal conditioning system, the first heat exchanger is configured to operate as a condenser. [9] According to another aspect of the thermal conditioning system, the second heat exchanger is configured to operate as an evaporator.

[0010] According to another aspect of the present disclosure, the third heat exchanger is configured to exchange heat with an airflow external to the passenger compartment of a motor vehicle.

[0011] The third heat exchanger is configured to operate selectively as an evaporator or condenser.

[0012] The first refrigerant accumulation device is a desiccant bottle.

[0013] According to one embodiment, the main loop comprises a second refrigerant fluid accumulation device arranged between the second heat exchanger and the second connection point.

[0014] The second refrigerant accumulation device protects the compressor against the presence of refrigerant in liquid form when the ambient temperature is negative.

[0015] The second refrigerant accumulation device is an accumulator.

[0016] According to one embodiment of the thermal conditioning system, the eighth connection point is arranged on the main loop between the second expansion valve and the second heat exchanger.

[0017] According to an alternative embodiment of the thermal conditioning system, the eighth connection point is arranged on the main loop between the second heat exchanger and the second accumulation device.

[0018] According to one embodiment, the thermal conditioning system comprises a refrigerant distribution module comprising: - a first refrigerant fluid inlet, - a second refrigerant fluid inlet, - a refrigerant fluid outlet, - a first channel connecting the first input to the output, - a second channel connecting the second input to a connection point arranged on the first channel between the first input and the output, - the second accumulation device, - the fourth relaxation device. The second accumulation device is arranged on the first channel between the connection point and the outlet, and the fourth expansion device is arranged on the second channel between the second inlet and the connection point.

[0019] According to one embodiment of the thermal conditioning system, the first heat transfer fluid is an air flow inside a passenger compartment of the vehicle.

[0020] According to one embodiment, the thermal conditioning system comprises a fifth bypass branch connecting a ninth connection point arranged on the main loop between the first connection point and the second expansion valve to a tenth connection point arranged on the main loop between the second accumulation device and the second connection point. The fifth bypass branch comprises a fifth expansion valve and a fourth heat exchanger.

[0021] The fourth heat exchanger is configured to operate as an evaporator.

[0022] According to one embodiment of the thermal conditioning system, the fourth heat exchanger is configured to exchange heat with an airflow inside the vehicle cabin.

[0023] Alternatively, the fourth heat exchanger is configured to exchange heat with an element of an electric powertrain of the motor vehicle.

[0024] According to a variant of the thermal conditioning system, the first heat transfer fluid is a heat transfer liquid.

[0025] In this variant, the thermal conditioning system comprises a heat transfer fluid circuit configured to circulate a heat transfer fluid.

[0026] In this variant, the first heat exchanger is a two-fluid heat exchanger arranged jointly on the refrigerant circuit and on the heat transfer fluid circuit so as to allow heat exchange between the refrigerant and the heat transfer liquid.

[0027] Still in this variant, the heat transfer fluid circuit comprises a fifth heat exchanger configured to exchange heat with an air flow inside the vehicle passenger compartment.

[0028] According to one aspect of the thermal conditioning system, the second heat exchanger is thermally coupled with an element of an electric powertrain of a motor vehicle.

[0029] An element of the vehicle's electric powertrain may include an electrical energy storage battery.

[0030] The battery can provide the energy needed to drive the vehicle.

[0031] The element of the electric powertrain of the vehicle may comprise an electric traction motor of the vehicle.

[0032] The element of the electric powertrain of the vehicle may comprise an electronic unit for controlling the electric traction motor of the vehicle.

[0033] According to an exemplary embodiment, the second heat exchanger is thermally coupled with the element via a heat transfer fluid circulating in a secondary heat transfer fluid loop.

[0034] The heat transfer fluid circulating in the secondary heat transfer fluid loop may be a dielectric fluid.

[0035] According to another embodiment, the second heat exchanger is in contact with the element of the vehicle's powertrain.

[0036] According to one aspect of the thermal conditioning system, the first bypass branch includes a first one-way valve configured to block a flow of refrigerant fluid from the fourth connection point to the first connection point.

[0037] According to another aspect of the thermal conditioning system, the second bypass branch includes a second one-way valve configured to block a flow of refrigerant fluid from the third connection point to the fourth connection point.

[0038] The first one-way valve can be a check valve. Similarly, the second one-way valve can be a check valve.

[0039] The main loop includes a shut-off valve located between the sixth connection point and the second connection point.

[0040] The fifth bypass branch includes a third check valve configured to block a flow of refrigerant fluid from the tenth connection point to the fourth heat exchanger.

[0041] Each check valve can be replaced with a shut-off valve.

[0042] According to one embodiment, the thermal conditioning system comprises a sixth bypass branch connecting an eleventh connection point arranged on the fourth bypass branch between the fourth expansion valve and the eighth connection point to a twelfth connection point arranged on the first bypass branch between the sixth connection point and the second connection point.

[0043] According to one embodiment of the thermal conditioning system, the main loop comprises an internal heat exchanger configured to allow heat exchange between the refrigerant fluid downstream of the first connection point and upstream of the second expansion valve and the refrigerant fluid downstream of the second accumulation device and upstream of the second connection point.

[0044] The internal heat exchanger increases the heat exchange capacity of the system, and also ensures overheating of the refrigerant at the compressor inlet, i.e. prevents the presence of liquid refrigerant droplets at the compressor inlet.

[0045] According to a variant of the thermal conditioning system, the main loop comprises a sixth expansion valve arranged on the main loop between the seventh connection point and the first heat exchanger.

[0046] This expansion valve expands the high-pressure refrigerant leaving the compressor. This allows the compressor to operate at its maximum allowable outlet pressure and expands the refrigerant before it circulates through the first heat exchanger. This increases the compression work, which increases the energy transferred to the refrigerant.

[0047] Each expansion device can be an electronic expansion valve.

[0048] The thermal conditioning system may comprise a first three-way valve arranged jointly on the main loop and on the third bypass branch, the first three-way valve being configured to selectively: - authorize circulation of the refrigerant fluid leaving the first exchanger to the third connection point and prohibit circulation of the refrigerant fluid leaving the first exchanger to the sixth connection point, or - authorize circulation of the refrigerant fluid leaving the first exchanger to the sixth connection point and prohibit circulation of the refrigerant fluid leaving the first exchanger to the third connection point.

[0049] According to an exemplary embodiment, the first three-way valve and the first expansion device are arranged in the same body.

[0050] In other words, a single component integrates the functions of a three-way valve and a pressure relief device. Integration is made easier.

[0051] The thermal conditioning system may also include a second three-way valve arranged jointly on the fourth bypass branch and on the sixth bypass branch, the second three-way valve being configured to selectively: - authorize circulation of the refrigerant fluid from the outlet of the fourth expansion valve to the eighth connection point and prohibit circulation of the refrigerant fluid from the outlet of the fourth expansion valve to the twelfth connection point, or - authorize circulation of the refrigerant fluid at the outlet of the fourth expansion valve to the twelfth connection point and prohibit circulation of the refrigerant fluid at the outlet of the fourth expansion valve to the eighth connection point.

[0052] The second three-way valve and the fourth pressure relief device can be arranged in the same body.

[0053] The disclosure also relates to a method of operating a thermal conditioning system as described above, in a first cabin cooling mode, in which: - a flow of low-pressure refrigerant fluid circulates in the compressor where it passes to high pressure, then circulates successively in the first heat exchanger without exchanging heat with the first heat transfer fluid, in the third bypass branch, in the third heat exchanger, in the second bypass branch, in the first refrigerant fluid accumulation device, in the fifth expansion device where it passes to low pressure, in the fourth heat exchanger where it evaporates by absorbing heat from the internal air flow, and returns to the compressor.

[0054] The disclosure also relates to a method of operating a thermal conditioning system as described above, in a so-called heat pump mode, in which: - a flow of low-pressure refrigerant fluid circulates in the compressor where it passes to high pressure, then circulates successively in the first heat exchanger, giving up heat to the first heat transfer fluid, in the first expansion device where it undergoes expansion to an intermediate pressure, in the first refrigerant fluid accumulation device, in the third expansion device where it passes to low pressure, in the third heat exchanger where it evaporates by absorbing heat from the outside air flow, and returns to the compressor.

[0055] The disclosure also relates to a method of operating a thermal conditioning system as described above, in a so-called energy recovery mode, in which: - a flow of low-pressure refrigerant fluid circulates in the compressor where it passes to high pressure, then circulates successively in the first heat exchanger, giving up heat to the first heat transfer fluid, in the first expansion device where it undergoes expansion to an intermediate pressure, in the first refrigerant fluid accumulation device, in the second expansion device where it passes to low pressure, in the second heat exchanger where it evaporates, absorbing heat, and returns to the compressor.

[0056] The disclosure also relates to a method of operating a thermal conditioning system as described above, in a second cabin cooling mode, in which: - a flow of low-pressure refrigerant fluid circulates in the compressor where it passes to high pressure, then circulates successively in the fourth bypass branch, in the fourth expansion valve, in the sixth bypass branch, in the third heat exchanger, in the third expansion device, in the second bypass branch, in the first accumulation device of refrigerant fluid, in the fifth expansion device where it passes at low pressure, in the fourth heat exchanger where it evaporates by absorbing heat from the internal air flow, and returns to the compressor. Brief description of the drawings

[0057] Other features, details and advantages will become apparent upon reading the detailed description below, and upon analyzing the attached drawings, in which:

[0058] [Fig. 1] is a schematic view of a thermal conditioning system according to a first embodiment of the invention,

[0059] [Fig. 2] is a schematic view of a thermal conditioning system according to a variant of the first embodiment of the invention,

[0060] [Fig. 3] is a schematic view of a thermal conditioning system according to a second embodiment of the invention,

[0061] [Fig. 4] is a schematic view of a thermal conditioning system according to a variant of the second embodiment of the invention,

[0062] [Fig. 5] is a schematic view of a thermal conditioning system according to a third embodiment of the invention,

[0063] [Fig. 6] is a schematic view of a thermal conditioning system according to a variant of the third embodiment of the invention,

[0064] [Fig. 7] is a schematic view of the thermal conditioning system of Figure 3, operating in a first mode of operation, called the first cooling mode,

[0065] [Fig. 8] is a schematic view of the thermal conditioning system of Figure 3, operating in a second mode of operation, called heat pump mode,

[0066] [Fig. 9] is a schematic view of the thermal conditioning system of Figure 3, operating in a third mode of operation, called energy recovery mode,

[0067] [Fig. 10] is a schematic view of the thermal conditioning system of Figure 5, operating in a fourth mode of operation, called the second cooling mode. Description of the embodiments

[0068] To facilitate reading the figures, the different elements are not necessarily represented to scale. In these figures, identical elements bear the same references. Some elements or parameters may be indexed, i.e. designated for example by first element or second element, or first parameter and second parameter, etc. This indexing is intended 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 names may be interchanged.

[0069] In the following description, the term "a first element upstream of a second element" means that the first element is placed before the second element relative to the direction of circulation, 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 relative to the direction of circulation, 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 passes successively through the first element, then the second element, without passing through the compression device. In other words, the refrigerant leaves the compression device, possibly passes through one or more elements, then passes through the first element, then the second element, then returns to the compression device, possibly after passing through other elements.

[0070] The term "a second element is placed between a first element and a third element" means that the shortest path from the first element to the third 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 this subsystem.

[0072] An electronic control unit 44 receives information from various sensors measuring in particular the characteristics of the refrigerant fluid at various points in the circuit. The electronic control unit 44 also receives instructions issued by the occupants of the vehicle, such as for example the desired temperature inside the passenger compartment. The electronic control unit 44 can also receive instructions from other electronic subsystems, such as for example the electrical energy storage battery management system. The electronic control unit 44 implements control laws allowing the control of the various actuators, in order to ensure the control of the thermal conditioning system 100 so as to ensure the instructions received.

[0073] The refrigerant circuit 10 forms a closed circuit in which the refrigerant can circulate. The refrigerant circuit 10 is sealed when it is in a nominal operating state, i.e. without defects or leaks. Each connection point of the circuit 10 allows the refrigerant to pass into one or other of the circuit portions joining at this connection point. The distribution of the refrigerant between the circuit portions joining at a connection point is achieved by adjusting the opening or closing of the shut-off valves, non-return valves or expansion devices included on each of the branches. In other words, each connection point is a means of redirecting the refrigerant arriving at this connection point.Various shut-off valves and non-return valves thus make it possible to selectively direct the refrigerant fluid into the different branches of the refrigerant circuit, in order to ensure different operating modes, as will be described later.

[0074] The refrigerant used by the refrigerant circuit 10 is here a chemical fluid such as R1234yf. Other refrigerants can also be used instead, such as for example R134a, or R290.

[0075] Interior air flow Fi is understood to mean an air flow to the passenger compartment of the motor vehicle. This interior air flow Fi can circulate in a heating, ventilation and / or air conditioning installation, frequently referred to by the English term "HVAC", for "Heating, Ventilating and Air Conditioning". This installation has not been shown in the various figures. A first group motor-fan, not shown, is arranged in the heating, ventilation and / or air conditioning installation in order to increase the flow rate of the interior air flow Fi if necessary.

[0076] Outside air flow Fe is understood to mean an air flow that is not intended for the passenger compartment of the vehicle. In other words, this air flow Fe remains outside the passenger compartment of the vehicle. A second motor-fan unit, also not shown, can be activated in order to increase the flow rate of the outside air flow Fe if necessary. The air flow rate provided by the first and second motor-fan units can be adjusted in real time according to the heat exchange requirements, for example by the electronic unit 44 for controlling the thermal conditioning system 100.

[0077] The term "first exchanger" is equivalent to the term "first heat exchanger". The term "accumulation device" is equivalent to the term "refrigerant accumulation device".

[0078] The heat transfer fluid circuit(s) also form one or more closed and sealed circuits in which a heat transfer fluid can circulate.

[0079] Figure 1 shows a thermal conditioning system 100 for a motor vehicle, according to a first embodiment. This thermal conditioning system 100 comprises 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 circulation of the refrigerant fluid: -- a compressor 6, -- a first heat exchanger 1 configured to exchange heat with a first heat transfer fluid F1, -- a first expansion valve 31, -- a first refrigerant fluid accumulation device 8, -- a second regulator 32, -- a second heat exchanger 2, A first branch of derivation B connecting a first point of connection 11 arranged on the main loop A between the first refrigerant fluid accumulation device 8 and the second expansion valve 32 at a second connection point 12 arranged on the main loop A between the second heat exchanger 2 and an inlet 6a of the compressor 6, the first bypass branch B comprising a third expansion valve 33 and a third heat exchanger 3, - A second bypass branch C connecting a third connection point 13 arranged on the main loop A between the first expansion valve 31 and the first refrigerant fluid accumulation device 8 to a fourth connection point 14 arranged on the first bypass branch B between the first connection point 11 and the third expansion valve 33, - A third branch D connecting a fifth connection point 15 arranged on the main loop A between the first expansion valve 31 and the third connection point 13 to a sixth connection point 16 arranged on the first branch B between the third heat exchanger 3 and the second connection point 12, - A fourth branch branch E connecting a seventh connection point 17 arranged on the main loop A between an outlet 6b of the compressor 6 and the first heat exchanger 1 to an eighth connection point 18 arranged on the main loop A between the second expansion valve 32 and the second connection point 12, the fourth branch branch E comprising a fourth expansion valve 34.

[0080] This refrigerant circuit architecture makes it possible to obtain numerous operating modes, in particular allowing heating of the first heat transfer fluid F1 at the first exchanger 1 from heat recovered at the second exchanger 2 or at the third exchanger 3. The fourth bypass branch E also makes it possible to increase the flow rate of refrigerant compressed by the compressor 6 and circulating in the circuit 10, which makes it possible to increase the thermal power supplied to the refrigerant. The heating capacity of the thermal conditioning system is thereby improved, i.e. increased. Compared to traditional architectures, this architecture makes it possible to do without an additional heating device. It also eliminates the need for a subcooling exchanger. This simplifies the system without any loss of performance.

[0081] The first heat exchanger 1 is configured to operate as a condenser.

[0082] The first heat transfer fluid F1 is an interior air flow Fi to a passenger compartment of the vehicle. The first exchanger 1 thus makes it possible to directly heat the interior air flow Fi, and thus to heat the passenger compartment of the vehicle.

[0083] The second heat exchanger 2 is configured to operate as an evaporator.

[0084] The second heat exchanger 2 is thermally coupled with an element 30 of an electric powertrain of a motor vehicle. The second heat exchanger 2 thus makes it possible to cool the element 30 of the powertrain, in order to maintain its temperature within an acceptable limit.

[0085] The element 30 of the electric powertrain of the vehicle may comprise an electrical energy storage battery. The battery may provide the energy necessary for traction of the vehicle.

[0086] Alternatively or additionally, the element 30 of the electric powertrain of the vehicle may comprise an electric traction motor of the vehicle.

[0087] Alternatively, or in addition, the element 30 of the electric traction chain of the vehicle may comprise an electronic unit for controlling the electric traction motor of the vehicle.

[0088] According to the illustrated examples, the second heat exchanger 2 is thermally coupled with the element 30 via a heat transfer liquid circulating in a secondary loop 41 of heat transfer liquid.

[0089] The heat transfer fluid circulating in the secondary heat transfer fluid loop 41 may be a dielectric fluid. The heat transfer fluid circulating in the secondary heat transfer fluid loop 41 may, alternatively, be a mixture of water and glycol.

[0090] According to a variant not shown, the second heat exchanger 2 is in contact with the element 30 of the vehicle's powertrain.

[0091] The third heat exchanger 3 is configured to exchange heat with an air flow Fe outside the passenger compartment of a motor vehicle. The third heat exchanger 3 is configured to operate selectively as an evaporator or as a condenser. The third heat exchanger 3 is designated by the term evapo-condenser. The third exchanger 3 is for example arranged on the front face of the vehicle, behind the grille. The third exchanger 3 thus receives an air flow generated by the movement of the vehicle. The third heat exchanger 3 can, depending on the operating modes of the thermal conditioning system, recover heat from the outside air flow Fe and transfer it to the refrigerant, or dissipate the heat of the refrigerant in the outside air flow.

[0092] The first refrigerant fluid accumulation device 8 is a desiccant bottle. The desiccant bottle 8 receives at its inlet 8a a two-phase mixture of refrigerant fluid. The refrigerant fluid leaving the outlet 8b of the desiccant bottle is in the state of saturated liquid. The first accumulation device makes it possible to compensate for variations depending on the operating conditions of the quantity of refrigerant fluid circulating in the circuit 10.

[0093] According to the examples illustrated, the main loop A comprises a second refrigerant fluid accumulation device 9 arranged between the second heat exchanger 2 and the second connection point 12.

[0094] The second refrigerant fluid accumulation device 9 makes it possible to protect the compressor 6 against the presence of refrigerant fluid in liquid form, in particular when the ambient temperature is negative. The second refrigerant fluid accumulation device 9 is an accumulator.

[0095] According to the embodiment of figure 1, the eighth connection point 18 is arranged on the main loop A between the second expansion valve 32 and the second heat exchanger 2. This arrangement is common with the variant of the first embodiment, illustrated in figure 2, with the second embodiment, figure 3, and with the variant of the third embodiment, figure 6.

[0096] According to a variant of this first embodiment, illustrated in figure 2, the first heat transfer fluid F1 is a heat transfer liquid.

[0097] In this variant, the thermal conditioning system comprises a heat transfer fluid circuit 40 configured to circulate a heat transfer fluid. The first heat exchanger 1 is a two-fluid heat exchanger arranged jointly on the refrigerant circuit 10 and on the heat transfer fluid circuit 40 so as to allow heat exchange between the refrigerant and the heat transfer fluid.

[0098] Still in this variant, the heat transfer fluid circuit 40 comprises a fifth heat exchanger 5 configured to exchange heat with an air flow Fi inside the passenger compartment of the vehicle. The fifth exchanger 5 is arranged in the heating, ventilation and / or air conditioning system and makes it possible to heat the passenger compartment of the vehicle.

[0099] In the second embodiment and the third embodiment, as well as their variants, illustrated in Figures 3 to 6, the first heat transfer fluid F1 is an interior air flow Fi to a passenger compartment of the vehicle. According to variants not shown, the first heat transfer fluid F1 is a heat transfer liquid, as described above for the variant of the first embodiment and shown in Figure 2.

[0100] Figure 3 shows a second embodiment.

[0101] According to this second embodiment, the thermal conditioning system 100 comprises a fifth branch F connecting a ninth connection point 19 arranged on the main loop A between the first connection point 11 and the second expansion valve 32 to a tenth connection point 20 arranged on the main loop A between the second accumulation device 9 and the second connection point 12. The fifth branch F comprises a fifth expansion valve 35 and a fourth heat exchanger 4.

[0102] The fourth heat exchanger 4 is here configured to exchange heat with an air flow Fi inside the vehicle passenger compartment. The fifth expansion valve 35 is arranged upstream of the fourth heat exchanger 4. The fourth heat exchanger 4 is thus configured to operate as an evaporator. The fourth heat exchanger 4 makes it possible to cool the passenger compartment of the vehicle in order to ensure the thermal comfort of the occupants. The fourth heat exchanger is arranged in the heating, ventilation and / or air conditioning system of the vehicle. According to a variant not shown, the fourth heat exchanger 4 is configured to exchange heat with an element of an electric powertrain of the motor vehicle. In other words, the fourth heat exchanger 4 can be thermally coupled with an element of an electric powertrain of the motor vehicle. The second exchanger 2 and the fourth exchanger 4 have similar roles in this case, allowing the cooling or energy recovery of one or more elements of the powertrain.

[0103] According to a variant of the second embodiment, shown diagrammatically in Figure 4, the eighth connection point 18 is arranged on the main loop A between the second heat exchanger 2 and the second accumulation device 9.

[0104] In other words, the variant of figure 4 differs from the embodiment of figure 3 in particular by the position of the connection point of the downstream part of the fourth branch of derivation E with the main branch A.

[0105] This variant of the position of the eighth connection point 18 is also applicable to the first embodiment, and has not been shown for this first embodiment.

[0106] In this variant of the second embodiment, the thermal conditioning system 100 comprises a refrigerant fluid distribution module 45 comprising: - a first E1 refrigerant fluid inlet, - a second E2 refrigerant fluid inlet, - a refrigerant fluid outlet S, - a first channel C1 connecting the first input E1 to the output S, - a second channel C2 connecting the second input E2 to a connection point P arranged on the first channel C1 between the first input E1 and the output S, - the second accumulation device 9, - the fourth trigger device 34.

[0107] The second accumulation device 9 is arranged on the first channel C1 between the connection point P and the output S, and the fourth expansion device 34 is arranged on the second channel C2 between the second input E2 and the connection point P.

[0108] Connection point P corresponds to the eighth connection point 18.

[0109] The module 45 thus integrates the fourth expansion valve 34, the second refrigerant fluid accumulation device 9, as well as two refrigerant fluid inlets and one refrigerant fluid outlet. The integration of the thermal conditioning system in the vehicle is thus facilitated, because the module makes it possible to reduce the size and the number of fluid connections to be connected. Indeed, the connections necessary to connect the inlets / outlets of the accumulation device 9 and the expansion valve 34 are internal to the module 45. The module 45 may comprise a machined casting in which the various components are integrated.

[0110] Figure 5 shows a third embodiment.

[0111] According to this third embodiment, the thermal conditioning system 100 comprises a sixth branch branch G connecting an eleventh connection point 21 arranged on the fourth branch branch E between the fourth expansion valve 34 and the eighth connection point 18 to a twelfth connection point 22 arranged on the first branch branch B between the sixth connection point 16 and the second connection point 12.

[0112] The high-pressure refrigerant fluid leaving the compressor 6 can thus reach the third exchanger 3, then operating as a condenser, without passing through the first exchanger 1. The pressure loss is thus minimized, which improves the performance of the system.

[0113] The twelfth connection point 22 can be confused with the sixth connection point 16.

[0114] According to a variant of the third embodiment, illustrated in FIG. 6, the main loop A comprises a sixth expander 36 arranged on the main loop A between the seventh connection point 17 and the first heat exchanger 1.

[0115] This expansion valve 36 makes it possible to expand the high-pressure refrigerant fluid leaving the compressor 6. It is thus possible to operate the compressor at its maximum admissible outlet pressure, and to expand the refrigerant fluid before its circulation in the first heat exchanger 1. The compression work is thus increased, which makes it possible to increase the energy transferred to the refrigerant fluid.

[0116] The sixth regulator 36 can be implemented in each embodiment. The sixth regulator 36 has also been shown for the second embodiment variant illustrated in FIG. 4.

[0117] The first expansion device 31 is an electronic expansion valve. The second expansion device 32 is an electronic expansion valve.

[0118] Each expansion device 31, 32, 33, 34, 35, 36 may be an electronic expansion valve.

[0119] In an electronic expansion valve, the flow area for the refrigerant to pass through can be continuously adjusted between a closed position and a fully open position. To achieve this, a control unit in the thermal conditioning system drives an electric motor that moves a movable shutter controlling the flow area offered to the refrigerant.

[0120] In the illustrated examples, the first bypass branch B comprises a first one-way valve 25 configured to block a circulation of refrigerant fluid from the fourth connection point 14 to the first connection point 11.

[0121] The first one-way valve 25 is configured to allow circulation of refrigerant fluid from the first connection point 11 to the fourth connection point 14.

[0122] The second bypass branch C comprises a second one-way valve 26 configured to block a circulation of refrigerant fluid from the third connection point 13 to the fourth connection point 14.

[0123] The second one-way valve 26 is configured to allow circulation of refrigerant fluid from the fourth connection point 14 to the third connection point 13.

[0124] The first one-way valve 25 is here a check valve. Similarly, the second one-way valve 26 is here a check valve. A check valve is a passive member that does not require electrical control.

[0125] The third branch of bypass D does not include a shut-off valve or heat exchanger.

[0126] The main loop A comprises a shut-off valve 29 arranged between the sixth connection point 16 and the second connection point 12.

[0127] The shut-off valve 29 makes it possible to selectively interrupt the circulation of refrigerant fluid in the first bypass branch B between the sixth connection point 16 and the second connection point 12. The shut-off valve 29 is electrically controlled, for example by the control unit 44.

[0128] The fifth bypass branch F comprises a third one-way valve 27 configured to block a circulation of refrigerant fluid from the tenth connection point 20 to the fourth heat exchanger 4.

[0129] The third one-way valve 27 is configured to allow circulation of refrigerant fluid from the fourth heat exchanger 4 to the tenth connection point 20. The third one-way valve 27 is here a non-return valve.

[0130] According to variants not shown, each non-return valve 25, 26, 27 can be replaced by an electrically controlled stop valve.

[0131] The main loop A of the thermal conditioning system 100 may comprise an internal heat exchanger 7 configured to allow heat exchange between the refrigerant fluid downstream of the first point of connection 1 1 and upstream of the second expansion valve 32 and the refrigerant fluid downstream of the second accumulation device 9 and upstream of the second connection point 12.

[0132] This characteristic, present in the second and third embodiments, figures 3 to 6, can also be applied to the first embodiment as well as to their variants.

[0133] The internal heat exchanger 7 makes it possible to increase the heat exchange capacity of the thermal conditioning system 100, and also contributes to ensuring overheating of the refrigerant fluid at the inlet of the compressor 1, i.e. contributes to avoiding the presence of droplets of liquid refrigerant at the inlet of the compressor 1.

[0134] The internal heat exchanger 7 comprises a first heat exchange section 7a arranged on the main loop A downstream of the first connection point 11 and upstream of the second expansion valve 32, as well as a second heat exchange section 7b arranged on the main loop A downstream of the second accumulation device 9 and upstream of the second connection point 12. The first internal heat exchanger 7 is configured to allow heat exchange between the refrigerant in the first heat exchange section 7a and the refrigerant in the second heat exchange section 7b. The refrigerant circulating at high pressure in the main loop A can thus transfer heat to the refrigerant circulating at a lower pressure in the main loop A, after expansion in the second expansion valve 32.When the thermal conditioning system 100 comprises the fifth bypass branch F, the first heat exchange section 7a is arranged downstream of the first connection point 11 and upstream of the ninth connection point 19. The second heat exchange section 7b is arranged between the tenth connection point 20 and the second connection point 12.

[0135] In the examples illustrated, the thermal conditioning system 100 comprises a first three-way valve 47 arranged jointly on the main loop A and on the third bypass branch D. The first three-way valve 47 is configured to selectively: - authorize circulation of the refrigerant fluid at the outlet of the first exchanger 1 to the third connection point 13 and prohibit circulation of the refrigerant fluid at the outlet of the first exchanger 1 to the sixth connection point 16, or - authorize circulation of the refrigerant fluid at the outlet of the first exchanger 1 to the sixth connection point 16 and prohibit circulation of the refrigerant fluid at the outlet of the first exchanger 1 to the third connection point 13.

[0136] According to an exemplary embodiment, the first three-way valve 47 and the first pressure reducing device 31 are arranged in the same body. The body may, for example, be a cast body. The body receiving the first three-way valve 47 and the first pressure reducing device 31 may be a single-piece body.

[0137] In other words, a single component integrates the functions of a three-way valve and an expansion device. Integration of the component into the thermal conditioning system is facilitated.

[0138] According to the third embodiment and its variant, illustrated in Figures 5 and 6, the thermal conditioning system 100 also comprises a second three-way valve 48 arranged jointly on the fourth bypass branch E and on the sixth bypass branch G. The second three-way valve 48 is configured to selectively: - authorize circulation of the refrigerant fluid at the outlet of the fourth expansion valve 34 to the eighth connection point 18 and prohibit circulation of the refrigerant fluid at the outlet of the fourth expansion valve 34 to the twelfth connection point 22, or - authorize circulation of the refrigerant fluid at the outlet of the fourth expansion valve 34 towards the twelfth connection point 22 and prohibit circulation of the refrigerant fluid at the outlet of the fourth expansion valve 34 towards the eighth connection point 18.

[0139] The second three-way valve 48 and the fourth pressure relief device 34 may be arranged in the same body. The body may, for example, be a foundry body. The body receiving the second three-way valve 48 and the fourth relaxation device 34 can be in one piece. This body is separate from the body receiving the first three-way valve 47 and the first relaxation device 31.

[0140] Each three-way valve 47, 48 can also be replaced by two two-way valves.

[0141] Figure 7 illustrates a method of operating a thermal conditioning system 100 as described previously, in a first cabin cooling mode. In this so-called passenger compartment cooling mode: - a flow Q of low-pressure refrigerant fluid circulates in the compressor 6 where it passes to high pressure, then circulates successively in the first heat exchanger 1 without exchanging heat with the first heat transfer fluid F1, in the third bypass branch D, in the third heat exchanger 3, in the second bypass branch C, in the first refrigerant fluid accumulation device 8, in the fifth expansion device 35 where it passes to low pressure, in the fourth heat exchanger 4 where it evaporates by absorbing heat from the interior air flow Fi, and returns to the compressor 1.

[0142] In this operating mode, the first expansion valve 31 is wide open so as not to expand the high-pressure refrigerant. A flap, not shown, isolates the first exchanger 1 from the interior air flow Fi which is here the first heat transfer fluid F1. A heat exchange between the refrigerant and the interior air flow Fi is thus avoided.

[0143] The first three-way valve 47 directs the high-pressure refrigerant to the third bypass branch D. The shut-off valve 29 is closed, so that the refrigerant flows from the sixth connection point 16 to the fourth connection point 14 and condenses in the third exchanger 3. Partial expansion in the third expansion valve 33 is possible.

[0144] The refrigerant fluid then circulates in the second branch C. In fact, the first non-return valve 25 blocks the circulation from the fourth connection point 14 to the first connection point 11. The second non-return valve 26 allows circulation of refrigerant fluid from the fourth connection point 14 to the third connection point 13. The refrigerant fluid then passes through the first accumulator 8, then reaches the ninth connection point 19. The second expansion valve 32 is in the closed position, so that there is no circulation of refrigerant fluid in the second exchanger 2. The refrigerant fluid is expanded by passing through the fifth expansion valve 35, and passes at low pressure. The low-pressure refrigerant fluid evaporates in the fourth exchanger 4 and cools the interior air flow Fi. The refrigerant fluid reaches the compressor 6, passing successively through the tenth connection point 10 and the second connection point 12.

[0145] Figure 8 illustrates a method of operating a thermal conditioning system 100 as described previously, in a so-called heat pump mode. In this so-called heat pump mode: - a flow Q of low-pressure refrigerant fluid circulates in the compressor 6 where 11 passes at high pressure, then circulates successively in the first heat exchanger 1 by giving up heat to the first heat transfer fluid F1, in the first expansion device 31 where it undergoes expansion to an intermediate pressure, in the first refrigerant fluid accumulation device 8, in the third expansion device 33 where it passes at low pressure, in the third heat exchanger 3 where it evaporates by absorbing heat from the outside air flow Fe, and returns to the compressor 6.

[0146] In this operating mode, the high-pressure refrigerant fluid at the outlet of the compressor 6 condenses in the first exchanger 1, which makes it possible to heat the interior air flow Fi, which is here the first heat transfer fluid F1. Then the refrigerant fluid undergoes partial expansion in the first expansion device 31 and passes to intermediate pressure. The intermediate pressure is a pressure lower than the high pressure, and higher than the low pressure. The partial expansion makes it possible to reduce the enthalpy of the refrigerant fluid at the outlet of the first accumulation device 8, and thus increase the recoverable energy at the level of the third exchanger 3. The first three-way valve 47 blocks the circulation of refrigerant fluid in the third bypass branch C and directs the refrigerant fluid from the fifth connection point 15 to the third connection point 13. The refrigerant then passes through the first accumulation device 8. The second expansion valve 32 and the fifth expansion valve 35 are in the closed position, so that there is no circulation of refrigerant from the first connection point 11 to the ninth connection point 19. The first non-return valve 25 allows circulation of refrigerant in the first bypass branch B, from the first connection point 11 to the second connection point 12. The third expansion valve 33 expands the refrigerant to a low pressure state. The low pressure refrigerant evaporates in the third exchanger 3 by absorbing heat from the outside air flow Fe. The stop valve 29 is open, and the evaporated refrigerant returns to the inlet 6a of the compressor 6. It is noted that the direction of travel of the refrigerant in the third exchanger 3 is reversed compared to the previous operating mode.

[0147] Figure 9 illustrates a method of operating a thermal conditioning system 100 as described previously, in a so-called energy recovery mode. According to this so-called energy recovery mode: - a flow Q of low-pressure refrigerant fluid circulates in the compressor 6 where it passes to high pressure, then circulates successively in the first heat exchanger 1 while giving up heat to the first heat transfer fluid F1, in the first expansion device 31 where it undergoes expansion to an intermediate pressure, in the first refrigerant fluid accumulation device 8, in the second expansion device 32 where it passes to low pressure, in the second heat exchanger 2 where it evaporates while absorbing heat, and returns to the compressor 6.

[0148] The circulation of refrigerant fluid between the outlet 6b of the compressor 6 and the first connection point 11 is identical to the previous operating mode. In the operating mode of Figure 9, the third expansion valve 33 is in the closed position, and the second expansion valve 32 is in the partially open position. There is therefore no circulation of refrigerant fluid in the third exchanger 3, while the refrigerant fluid circulates in the second exchanger 2. The refrigerant fluid expanded by the second expansion valve 32 evaporates in the second exchanger 2 by absorbing heat from the element 30 of the powertrain. This operating mode makes it possible to recover energy from the powertrain of the vehicle at the second exchanger 2 and to transfer it to the interior air flow Fi at the first exchanger 1. The evaporated refrigerant fluid passes through the second accumulation device 9 and reaches the compressor 6. When the ambient temperature is negative, the second accumulation device 9 prevents drops of liquid refrigerant from reaching the inlet 6a of the compressor 6.

[0149] These three operating modes have been shown for a thermal conditioning system according to the second embodiment. They are also applicable to the other embodiments of the thermal conditioning system, as well as to their variant.

[0150] Figure 10 illustrates a method of operating a thermal conditioning system 100 as described previously, in a second cabin cooling mode. According to this mode of operation: - a flow Q of low-pressure refrigerant fluid circulates in the compressor 1 where it passes to high pressure, then circulates successively in the fourth bypass branch E, in the fourth expansion valve 34, in the sixth bypass branch G, in the third heat exchanger 3, in the third expansion device 33, in the second bypass branch C, in the first refrigerant fluid accumulation device 8, in the fifth expansion device 35 where it passes to low pressure, in the fourth heat exchanger 4 where it evaporates by absorbing heat from the interior air flow Fi, and returns to the compressor 1.

[0151] This mode of operation relates to a thermal conditioning system according to the third embodiment as well as its variant, illustrated respectively in figures 5 and 6.

[0152] In this mode of operation, the first expansion valve 31 is in the closed position, which prevents the circulation of refrigerant fluid in the first exchanger 1. The fourth expansion valve 34 is in the open position. The second three-way valve 48 blocks the circulation in the fourth bypass branch E between the eleventh connection point 21 and the eighth connection point 18, and directs the high-pressure refrigerant into the sixth bypass branch G. The shut-off valve 29 is in the closed position, so that the refrigerant circulates in the third exchanger 3. The circulation of the refrigerant between the sixth connection point 16 and the inlet 6a of the compressor 6 is identical to that described in the first passenger compartment cooling mode, shown in Figure 7.

[0153] Many other modes of operation are also possible, and have not been shown.

Claims

Claims

1. 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 circulation of the refrigerant fluid: -- a compressor (6), -- a first heat exchanger (1) configured to exchange heat with a first heat transfer fluid (F1), -- a first regulator (31), -- a first refrigerant fluid accumulation device (8), -- a second regulator (32), -- a second heat exchanger (2), A first bypass branch (B) connecting a first connection point (11) arranged on the main loop (A) between the first refrigerant fluid accumulation device (8) and the second expansion valve (32) to a second connection point (12) arranged on the main loop (A) between the second heat exchanger (2) and an inlet (6a) of the compressor (6), the first bypass branch (B) comprising a third expansion valve (33) and a third heat exchanger (3), - A second bypass branch (C) connecting a third connection point (13) arranged on the main loop (A) between the first expansion valve (31) and the first refrigerant fluid accumulation device (8) to a fourth connection point (14) arranged on the first bypass branch (B) between the first connection point (11) and the third expansion valve (33), - A third branch branch (D) connecting a fifth connection point (15) arranged on the main loop (A) between the first expansion valve (31) and the third connection point (13) to a sixth connection point (16) arranged on the first branch branch (B) between the third heat exchanger (3) and the second connection point (12), - A fourth branch branch (E) connecting a seventh connection point (17) arranged on the main loop (A) between an output (6b) of the compressor (6) and the first heat exchanger (1) at an eighth connection point (18) arranged on the main loop (A) between the second expansion valve (32) and the second connection point (12), the fourth bypass branch (E) comprising a fourth expansion valve (34).

2. Thermal conditioning system (100) according to claim 1, wherein the main loop (A) comprises a second refrigerant fluid accumulation device (9) arranged between the second heat exchanger (2) and the second connection point (12).

3. Thermal conditioning system (100) according to claim 1 or 2, wherein the eighth connection point (18) is arranged on the main loop (A) between the second expansion valve (32) and the second heat exchanger (2).

4. Thermal conditioning system (100) according to claim 2, wherein the eighth connection point (18) is arranged on the main loop (A) between the second heat exchanger (2) and the second accumulation device (9).

5. Thermal conditioning system (100) according to one of the preceding claims in combination with claim 2, comprising a refrigerant fluid distribution module (45) comprising: - a first inlet (E1) of refrigerant fluid, - a second inlet (E2) for refrigerant fluid, - a refrigerant outlet (S), - a first channel (C1) connecting the first input (E1) to the output (S), - a second channel (C2) connecting the second input (E2) to a connection point (P) arranged on the first channel (C1) between the first input (E1) and the output (S), - the second accumulation device (9), - the fourth expansion device (34), in which the second accumulation device (9) is arranged on the first channel (C1) between the connection point (P) and the outlet (S), and in which the fourth expansion device (34) is arranged on the second channel (C2) between the second inlet (E2) and the connection point (P).

6. Thermal conditioning system (100) according to one of claims 1 to 5, in which the first heat transfer fluid (F1) is an air flow (Fi) inside a passenger compartment of the vehicle.

7. Thermal conditioning system (100) according to one of the preceding claims in combination with claim 2, comprising a fifth branch branch (F) connecting a ninth connection point (19) arranged on the main loop (A) between the first connection point (11) and the second expansion valve (32) to a tenth connection point (20) arranged on the main loop (A) between the second accumulation device (9) and the second connection point (12), the fifth branch branch (F) comprising a fifth expansion valve (35) and a fourth heat exchanger (4), in which the fourth heat exchanger (4) is configured to exchange heat with an air flow (Fi) inside the passenger compartment of the vehicle or with an element of an electric powertrain of the motor vehicle.

8. Thermal conditioning system (100) according to one of claims 1 to 5 or according to claim 7, wherein the first heat transfer fluid (F1) is a heat transfer liquid, wherein the thermal conditioning system (100) comprises a heat transfer liquid circuit (40) configured to circulate a heat transfer liquid, wherein the first heat exchanger (1) is a two-fluid heat exchanger arranged jointly on the refrigerant circuit (10) and on the heat transfer fluid circuit (40) so as to allow a heat exchange between the refrigerant and the heat transfer liquid, and wherein the heat transfer fluid circuit (40) comprises a fifth heat exchanger (5) configured to exchange heat with an air flow (Fi) inside the passenger compartment of the vehicle.

9. Thermal conditioning system (100) according to one of the preceding claims, wherein the second heat exchanger (2) is thermally coupled with an element (30) of an electric powertrain of a motor vehicle, the element (30) of the electric powertrain of the vehicle comprising a electric energy storage battery, or an electric traction motor of the vehicle, or an electronic control unit of the electric traction motor of the vehicle.

10. Thermal conditioning system (100) according to one of the preceding claims, wherein the first bypass branch (B) comprises a first one-way valve (25) configured to block a circulation of refrigerant fluid from the fourth connection point (14) to the first connection point (11), and wherein the second bypass branch (C) comprises a second one-way valve (26) configured to block a circulation of refrigerant fluid from the third connection point (13) to the fourth connection point (14).

11. Thermal conditioning system (100) according to one of the preceding claims, comprising a sixth bypass branch (G) connecting an eleventh connection point (21) arranged on the fourth bypass branch (E) between the fourth regulator (34) and the eighth connection point (18) to a twelfth connection point (22) arranged on the first bypass branch (B) between the sixth connection point (16) and the second connection point (12).

12. Thermal conditioning system (100) according to one of the preceding claims in combination with claim 2, wherein the main loop (A) comprises an internal heat exchanger (7) configured to allow heat exchange between the refrigerant fluid downstream of the first connection point (11) and upstream of the second expansion valve (32) and the refrigerant fluid downstream of the second accumulation device (9) and upstream of the second connection point (12).

13. Thermal conditioning system (100) according to one of the preceding claims, wherein the main loop (A) comprises a sixth expansion valve (36) arranged on the main loop (A) between the seventh connection point (17) and the first heat exchanger (1).

14. Thermal conditioning system (100) according to one of the preceding claims, comprising a first three-way valve (47) arranged jointly on the main loop (A) and on the third bypass branch (D), the first three-way valve (47) being configured to selectively: - authorize circulation of the refrigerant fluid at the outlet of the first exchanger (1) towards the third connection point (13) and prohibit circulation of the refrigerant fluid at the outlet of the first exchanger (1) towards the sixth connection point (16), or - allow circulation of the refrigerant fluid at the outlet of the first exchanger (1) towards the sixth connection point (16) and prohibit circulation of the refrigerant fluid at the outlet of the first exchanger (1) towards the third connection point (13), and in which the first three-way valve (47) and the first expansion device (31) are arranged in the same body.

15. Thermal conditioning system (100) according to one of the preceding claims in combination with claim 11, comprising a second three-way valve (48) jointly arranged on the fourth bypass branch (E) and on the sixth bypass branch (G), the second three-way valve (48) being configured to selectively: - authorize circulation of the refrigerant fluid at the outlet of the fourth expansion valve (34) to the eighth connection point (18) and prohibit circulation of the refrigerant fluid at the outlet of the fourth expansion valve (34) to the twelfth connection point (22), or - allow circulation of the refrigerant fluid at the outlet of the fourth expansion valve (34) to the twelfth connection point (22) and prohibit circulation of the refrigerant fluid at the outlet of the fourth expansion valve (34) to the eighth connection point (18), and in which the second three-way valve (48) and the fourth expansion device (34) are arranged in the same body.

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