THERMAL MANAGEMENT SYSTEM FOR HYBRID OR ELECTRIC VEHICLES

Abstract

Thermal management system for a hybrid or electric vehicle, comprising a reversible air conditioning circuit (10) comprising a compressor (12), a first heat exchanger (14), a second heat exchanger (16), a first refrigerant storage device (18), a first expansion member (20) and a cooling exchanger (22, 42). The circuit (10 further comprises a first bypass branch (24) between a first bypass point (26) located on the main loop (LP) between the first heat exchanger (14) and the second heat exchanger (16) and a first junction point (28) located on the main loop (LP) between the first refrigerant fluid storage device (18) and the first expansion member (20, said main loop (LP) further comprising a second refrigerant fluid storage device (30) between the first heat exchanger (14) and said first bypass point (26). Figure 1

Description

Title of the invention: THERMAL MANAGEMENT SYSTEM FOR HYBRID OR ELECTRIC VEHICLE Technical field of the invention

[0001] The invention relates to the field of motor vehicles and more particularly to a thermal management circuit for a hybrid or electric motor vehicle. Technical background

[0002] In electric and hybrid vehicles, the thermal management of the passenger compartment is generally managed by a reversible air conditioning circuit. By reversible, we mean that this air conditioning circuit can operate in a cooling mode in order to cool the air going to the passenger compartment and in a heat pump mode in order to heat the air going to the passenger compartment. This reversible air conditioning circuit can also include a bypass in order to manage the temperature of the batteries of the electric or hybrid vehicle. It is thus possible to cool or even heat the batteries thanks to the reversible air conditioning loop. In heat pump mode, the calories are taken from the outside air to be transmitted to an internal air flow which is blown into the passenger compartment to heat it.

[0003] It is known to use a refrigerant circuit successively comprising a compressor, an internal condenser, an expansion valve and an evaporator. The evaporator is for example used to cool the air in the cabin. In addition, the circuit typically comprises a bypass branch to an evapo-condenser on the front of the vehicle, which is used as a condenser in air conditioning mode and as an evaporator in heat pump mode.

[0004] One of the aims of the present invention is to improve the performance in air conditioning mode of such a system, while maintaining good performance in heat pump mode. Summary of the invention

[0005] One aspect of the invention relates to a thermal management system for a hybrid or electric vehicle, the thermal management system comprising a reversible air conditioning circuit in which a refrigerant circulates, the reversible air conditioning circuit successively comprising, in a main refrigerant loop, a compressor, a first heat exchanger arranged to exchange calories with a first heat transfer fluid, for example directly or indirectly, the first heat transfer fluid being for example an internal air flow blown into the passenger compartment of the vehicle, a second heat exchanger arranged to exchange calories with a first heat transfer fluid, for example directly or indirectly, the first heat transfer fluid being for example an internal air flow blown into the passenger compartment of the vehicle, a second heat exchanger arranged to exchange calories with a second heat transfer fluid, for example directly or indirectly, the first heat transfer fluid being for example an internal air flow blown into the passenger compartment of the vehicle, a third heat exchanger arranged to exchange calories with a second heat transfer fluid, for example directly or indirectly, the first heat transfer fluid being for example an internal air flow blown into the passenger compartment of the vehicle, a fourth ... calories with a second heat transfer fluid, for example directly or indirectly, the second heat transfer fluid being for example an external air flow on the front of the vehicle, in particular so that said second heat exchanger can operate as a cooler or condenser of refrigerant fluid when the system is in air conditioning mode, a first refrigerant fluid storage device, in particular to ensure a gas / liquid separation function, a first refrigerant fluid expansion member and a heat exchanger, called a cooling heat exchanger,

[0006] the refrigerant circuit further comprising a first bypass branch between a first bypass point located on the main loop between the first heat exchanger and the second heat exchanger, and a first junction point located on the main loop between the first refrigerant storage device and the first expansion member, in particular so that said cooling heat exchanger can operate as a refrigerant evaporator when said system is in heat pump mode, said main refrigerant loop further comprising a second refrigerant storage device between the first heat exchanger and said first bypass point.

[0007] This system makes it possible, thanks to the subcooling permitted by the first refrigerant storage device, to reduce the enthalpy of the fluid at the inlet of the cooling exchanger and thus to optimize the performance of the system in air conditioning mode. In addition, said first bypass branch allows the system to operate in other modes, in particular heat pump, heat recovery and / or dehumidification, by being located downstream of said first exchanger along the main loop. In these other modes, the second storage device provides the function of fluid storage reserve in the part of the circuit then traversed by the refrigerant, if necessary on its own and without the complement of the first storage device, this thanks to its positioning between the first exchanger and the first bypass point.This means that, if the first storage device is not traversed by the refrigerant fluid in certain operating modes, this is not the case for the second storage device which is traversed in each of the operating modes. Such a configuration allows a large number of operating modes while favoring the efficiency of the system in the air conditioning mode(s), these modes being in practice the most demanding modes in terms of energy consumption.

[0008] Preferably, said system is configured to operate, in a first case, in air conditioning mode by cooling a fluid, said to be cooled, passing through said cooling exchanger, using said refrigerant fluid passing through said loop. main, said refrigerant dissipating calories at said second exchanger.

[0009] Said system is further configured to operate alternately, in a second case, in heat pump mode by heating said fluid to be cooled using said refrigerant fluid then passing through said first bypass branch, said refrigerant fluid taking calories from said second exchanger.

[0010] Said system is further configured so that the refrigerant passes through the second exchanger in a first direction in the first case and in the opposite direction in the second case. This promotes the performance of the second heat exchanger in both air conditioning and heat pump mode. According to certain aspects of the invention, the above system comprises one or more of the characteristics below taken in isolation or in all technically possible combinations forming as many embodiments of the invention:

[0011] - the first refrigerant storage device is integrated into the second heat exchanger,

[0012] - the main loop, in particular the second heat exchanger, comprises a subcooling pass downstream of the first refrigerant storage device,

[0013] - said second exchanger comprises a heat exchange bundle, said bundle being provided with one or more first refrigerant circulation passes, located upstream of said first storage device in said main loop, said bundle further comprising said sub-cooling pass,

[0014] - an exchange surface of said first passes represents at least two thirds of a total exchange surface of said beam,

[0015] - said first storage device comprises a bottle, secured to said beam,

[0016] - said system comprises a filter and / or a desiccant for said refrigerant fluid,

[0017] - said filter and / or said desiccant are located at said second device of storage,

[0018] - said bottle is configured so that the circulation of the refrigerant fluid is free inside said bottle,

[0019] - said cooling exchanger is formed of a two-fluid exchanger, arranged jointly on a circuit of a third heat transfer fluid, the third heat transfer fluid being for example a heat transfer liquid forming where appropriate said fluid to be cooled,

[0020] - said third heat transfer fluid circuit comprises, in addition to said heat exchanger bifluid heat, a fourth heat exchanger arranged to exchange calories, directly or indirectly, with a fourth heat transfer fluid, the fourth fluid heat transfer fluid being for example an external air flow on the front of the vehicle, this embodiment of the invention being an original and inexpensive way of implementing the heat pump mode, using the two-fluid heat exchanger ("chiller") which is also used to cool the batteries in battery cooling mode, as a refrigerant evaporator, said third heat transfer fluid circulating in the two-fluid heat exchanger being passively cooled by the fourth heat exchanger,

[0021] -the refrigerant circuit comprises a first three-way valve connecting the second refrigerant storage device, the second heat exchanger and the first bypass branch to the first junction point,

[0022] - the cooling heat exchanger, in particular the heat exchanger bifluid, is connected to the compressor without the presence of another heat exchanger between the cooling heat exchanger and the compressor,

[0023] - the refrigerant circuit further comprises a second branch of refrigerant fluid rivation between a second bypass point and a second junction point, the second bypass point being located on the main loop between the second heat exchanger and the first expansion member, for example between the first junction point and the first expansion member, and the second junction point being located on the main loop between the cooling heat exchanger, in particular the two-fluid heat exchanger, and the compressor,

[0024] - the second branch of derivation comprises, in the direction of circulation of the fluid refrigerant, a second expansion member and a fifth heat exchanger arranged to exchange calories, directly or indirectly, with a fifth heat transfer fluid, in particular so that said fifth heat exchanger can operate as a refrigerant evaporator when the system is in air conditioning mode and in dehumidification mode, the fifth heat transfer fluid being for example an internal air flow blown into the passenger compartment of the vehicle, forming where appropriate said fluid to be cooled,

[0025] - the refrigerant circuit further comprises a third branch of refrigerant fluid rivation between a third diversion point and a third junction point,

[0026] - the third branch point is located on the main loop between the first refrigerant storage device and the first junction point of the first branch,

[0027] - alternatively, the third branch point is located on the main loop between said first diversion point and said second exchanger,

[0028] - the third junction point is located on the second branch of derivation between the fifth heat exchanger and the second junction point of the second branch branch,

[0029] - the third branch of the bypass comprises a stop valve,

[0030] -the second branch of the bypass comprises a first non-return valve located between the third junction point of the third branch of the diversion and the second junction point of the second branch of the diversion,

[0031] - the main loop has a second non-return valve located between the first refrigerant storage device and the first junction point of the first branch,

[0032] - the second non-return valve is located between the third branch point of the third branch of derivation and the first junction point of the first branch of derivation,

[0033] - the system comprises an indoor air ventilation device in which is arranged said first heat exchanger,

[0034] - the third heat transfer fluid circuit comprises a first branch of cir circulation of heat transfer fluid, the first heat transfer fluid branch comprising a first pump and the two-fluid heat exchanger, the third heat transfer fluid circuit also comprising a so-called "external" branch for circulation of the third heat transfer fluid, said external branch comprising said fourth heat exchanger, an upstream end of said external branch being connected to a downstream end of said first branch and a downstream end of said external branch being connected to an upstream end of said first branch, in particular so as to form together a third heat transfer fluid circulation loop,

[0035] - said first branch also comprises an electric heating device, preferably upstream of the two-fluid heat exchanger, preferably directly upstream,

[0036] - the third heat transfer fluid circuit comprises a second branch of cir culation of the third heat transfer fluid, an upstream end of the second circulation branch being connected to a downstream end of said first branch, for example downstream of the two-fluid heat exchanger, and a downstream end of said second branch being connected to an upstream end of said first branch, in particular so as to form together a circulation loop of third heat transfer fluid, said second branch preferably not comprising any device capable of significantly modifying the quantity of heat accumulated by the third heat transfer fluid,

[0037] -the third heat transfer fluid circuit comprises a third branch for circulating the third heat transfer fluid, said third branch comprising a second pump and a sixth heat exchanger, for example of the “electrical machines” type for exchanging heat with “electrical machines” of the vehicle,

[0038] - the third heat transfer fluid circuit comprises a fourth branch of cir circulation of the third heat transfer fluid, said fourth branch comprising a seventh heat exchanger, for example of the “battery” type for exchanging heat with “batteries” of the vehicle, an upstream end of said fourth branch being connected to a downstream end of said first branch and a downstream end of said fourth branch being connected to an upstream end of said first branch by a fifth branch for circulation of the third heat transfer fluid, in particular so as to form together a heat transfer fluid circulation loop, for example so as to allow the electric heating device to heat the third heat transfer fluid circulating in the seventh heat exchanger, or for example so as to allow, the two-fluid heat exchanger being active, to cool the third heat transfer fluid circulating in the seventh heat exchanger,

[0039] - an upstream end of the fourth branch is connected to a downstream end of said third branch, and a downstream end of said fourth branch is connected to an upstream end of said third branch, in particular so as to form together a circulation loop of third heat transfer fluid, for example so as to allow the third heat transfer fluid circulating in the seventh heat exchanger to be heated by recovering heat in the sixth heat exchanger,

[0040] - the third heat transfer fluid circuit comprises a sixth branch e cir circulation of the third heat transfer fluid, an upstream end of said sixth branch being connected to a downstream end of said third branch and a downstream end of said sixth branch being connected to an upstream end of said external branch, in particular so that said third branch, said sixth branch and said external branch together form a circulation loop of the third heat transfer fluid, in particular so as to allow the “passive” cooling of the third heat transfer fluid circulating in said sixth heat exchanger,

[0041] - the third heat transfer fluid circuit comprises an expansion tank, for example located on said external branch,

[0042] - the third heat transfer fluid circuit comprises a second three-way valve connecting a downstream end of said first branch, an upstream end of said second branch and an upstream end of said external branch, configured to allow the circulation of the third heat transfer fluid between said first branch and said second branch or between said first branch and said external branch, the first branch being for example connected via a seventh branch,

[0043] - the third heat transfer fluid circuit comprises a third non-return valve on an eighth branch connecting an upstream end of said first branch and a downstream end of said fourth branch, downstream of a fourth point of diversion towards said seventh branch and upstream of a fourth point of junction of said third branch to said fourth branch,

[0044] - the third heat transfer fluid circuit comprises a third three-way valve connecting a downstream end of said fourth branch, an upstream end of said fifth branch and an upstream end of said third branch, configured to allow the circulation of the third heat transfer fluid between said fourth branch and said fifth branch or between said fourth branch and said third branch,

[0045] - the third heat transfer fluid circuit comprises a fourth three-way valve connecting a downstream end of said third branch, an upstream end of said fourth branch and an upstream end of said sixth branch to allow the circulation of the third heat transfer fluid between said third branch and said fourth branch or between said third branch and said sixth branch,

[0046] - said main loop comprises a third expansion member,

[0047] - said third expansion member is located between said first derivation point of said first bypass branch and said second heat exchanger, in particular so that said second heat exchanger can operate as a refrigerant fluid evaporator when the system is in heat pump mode, for example jointly or not with the bifluid heat exchanger, also operating for example as a refrigerant fluid evaporator when the system is in heat pump mode,

[0048] - said third expansion member is integrated into the first three-way valve,

[0049] - said system comprises a fourth relaxation member,

[0050] - said fourth expansion member is located between said second exchanger of heat and the first junction point according to the direction of circulation of the refrigerant fluid in said main loop.

[0051] Another aspect of the invention relates to a method of operating a system produced according to any one of the preceding claims, in which, in a first heat pump mode, said first heat exchanger operates as a refrigerant condenser or cooler, the cooling heat exchanger, in particular the bifluid heat exchanger operating as a refrigerant evaporator or heater.

[0052] According to certain aspects of the invention, the above method comprises one or more of the characteristics below taken in isolation or in all technically possible combinations:

[0053] - in a second heat pump mode, said first heat exchanger and said second heat exchanger operates as a refrigerant condenser or cooler, the two-fluid heat exchanger operating as a refrigerant evaporator,

[0054] - in a first air conditioning mode, said first heat exchanger and said second heat exchanger works as a condenser or refrigerant cooler, the fifth heat exchanger works as a refrigerant evaporator,

[0055] - in a vehicle battery cooling mode, said first exchanger heat exchanger and said second heat exchanger operate as a refrigerant condenser or cooler, the two-fluid heat exchanger operating as a refrigerant evaporator,

[0056] - in a mode of air conditioning and joint cooling of the vehicle batteries, said first heat exchanger and said second heat exchanger operate as a refrigerant fluid condenser or cooler, the bifluid heat exchanger and said fifth heat exchanger operate as a refrigerant fluid evaporator,

[0057] - in a vehicle cabin dehumidification mode, said first heat exchanger operates as a refrigerant condenser or cooler, and said fifth heat exchanger operates as a refrigerant evaporator,

[0058] - in a third heat pump mode, said first heat exchanger operates as a refrigerant condenser or cooler, said second heat exchanger operating as a refrigerant evaporator,

[0059] -in a fourth heat pump mode, said first heat exchanger operates as a refrigerant fluid condenser or cooler, said second heat exchanger and the two-fluid heat exchanger operating as a refrigerant fluid evaporator, said third heat transfer fluid circulating in said two-fluid heat exchanger being for example heated in said fourth heat exchanger. Brief description of the figures

[0060] Other characteristics and advantages of the aspects of the invention will appear during the reading of the detailed description which follows, provided by way of illustrative example, and for the understanding of which reference will be made to the appended drawings described succinctly below.

[0061] [Fig.l] is a schematic view which represents an example of an air conditioning circuit which equips the thermal management system produced according to a first aspect of the invention.

[0062] [Fig. 2] is a view of an example of a heat transfer fluid circuit passing through the two-fluid heat exchanger of [Fig. 1].

[0063] [Fig.3] is a schematic view which represents the circuit of [Fig.l] in a first heat pump mode.

[0064] [Fig.4] is a schematic view showing the circuit of [Fig.l] in a battery cooling mode.

[0065] [Fig.5] is a schematic view showing the circuit of [Fig.l] in a joint dehumidification and heat pump mode.

[0066] [Fig. 6] is a schematic view which represents an example of an air conditioning circuit which equips the thermal management system produced according to a second aspect of the invention.

[0067] [Fig.7] is a schematic view showing the circuit of [Fig.6] in a heat pump mode.

[0068] [Fig.8] is a schematic view showing the circuit of [Fig.6] in another heat pump mode.

[0069] [Fig.9] is a schematic view showing the circuit of [Fig.6] in a combined heat pump and dehumidification mode.

[0070] [Fig. 10] is a schematic view which represents an example of an air conditioning circuit which equips the thermal management system produced according to a third aspect of the invention, in a joint cooling and air conditioning mode.

[0071] [Fig. 11] is a schematic view representing the circuit of [Fig. 10] in a joint heat recovery and heat pump mode.

[0072] [Fig. 12] is a schematic view showing the circuit of [Fig. 10] in a joint heat pump and cooling mode.

[0073] [Fig. 13] is a schematic view representing the circuit of [Fig. 10] in a joint mode of simple dehumidification and heat recovery.

[0074] [Fig. 14] is a schematic view showing the circuit of [Fig. 10] in a parallel dehumidification mode.

[0075] [Fig. 15] is a schematic view showing the circuit of [Fig. 10] in a joint series dehumidification and cooling mode.

[0076] [Fig. 16] is a schematic view showing, in elevation, a second heat exchanger in the circuit of [Fig. 10]. Detailed description of the invention

[0077] In the remainder of the description, elements having an identical structure or similar functions will be designated by the same reference.

[0078] 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 in relation 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 in relation to the direction of circulation, or path, of the fluid in question. The direction of circulation is defined by the arrows of the compressor or by the arrows of the pumps where applicable.

[0079] The term "branch" here refers to a section of circuit open at both ends comprising only elements arranged in series.

[0080] It should also be noted that the term “batteries” should not be understood as all the batteries in the vehicle but as several batteries.

[0081] The term “battery” should be understood to mean any energy storage unit capable of restoring this energy in electrical form.

[0082] In the drawings, the pipes in which the refrigerant fluid is moving will be represented by bold lines and the pipes in which the heat transfer fluid is not moving will be represented by thin lines.

[0083] Note that the terms “first”, “second”, “third” are simple designations not implying a precise number of components. Thus, one can refer to a “fifth” heat exchanger without there being five or more heat exchangers in the circuit, the circuit being able for example to have less than five.

[0084] As illustrated in the various figures, the invention relates to a thermal conditioning system. This is, for example, a thermal management system for a motor vehicle. This is an electric or hybrid motor vehicle which comprises an electric motor which provides engine torque to drive wheels of the vehicle. The electric motor is supplied with electric current at least by batteries, called traction batteries. During operation of the vehicle, the electric motor and the battery are likely to produce heat.

[0085] As more particularly illustrated in [Fig. 1], said system comprises a first air conditioning circuit 10 in which a refrigerant fluid circulates (or “refrigerant fluid circuit”), as shown in [Fig. 1], and a second heat transfer fluid circuit 11 in which a heat transfer fluid circulates, as shown in [Fig. 2].

[0086] The heat transfer fluid is, for example, a heat transfer liquid such as water comprising an antifreeze, in particular glycolated water, or any other suitable heat transfer fluid. The refrigerant is, for example, a hydrofluorocarbon, such as R-134a or R1234yf or R744.

[0087] As shown in [Fig.l], the circuit 10 is a reversible air conditioning circuit in which a refrigerant fluid circulates. Said circuit 10 is configured to carry out a thermodynamic loop successively comprising a phase of com pressure, a first phase of heat exchange with decrease in enthalpy, an expansion phase and a second phase of heat exchange with increase in enthalpy.

[0088] The refrigerant circuit 10 successively comprises, in the direction of circulation of the refrigerant, in a main loop LP of refrigerant, a compressor 12, a first heat exchanger 14 arranged to exchange calories with a first heat transfer fluid, a second heat exchanger 16 arranged to exchange calories with a second heat transfer fluid, a first storage device 18 of refrigerant, in particular to provide a gas / liquid separation function, a first expansion member 20 of the refrigerant and a cooling exchanger. Said cooling exchanger is for example, a two-fluid heat exchanger 22 arranged jointly on a circuit 11 of a third heat transfer fluid.

[0089] The first refrigerant storage device 18 is commonly called a “bottle”. It may include a refrigerant filter and / or desiccant. It provides a gas / liquid separation function so that the outgoing fluid is liquid.

[0090] The first expansion member 20 is typically an electronic fluid expansion valve or “electronic expander”.

[0091] The two-fluid heat exchanger 22 is here connected directly to the compressor 12, i.e. without the presence of another heat exchanger between the two-fluid heat exchanger 22 and the compressor 12.

[0092] The two-fluid heat exchanger 22 is configured to allow heat exchange between the refrigerant fluid, circulating in the air conditioning circuit 10, and the third heat transfer fluid, circulating in the circuit 11 of the third heat transfer fluid, without mixing between the heat transfer fluid and the refrigerant fluid. This type of heat exchanger is commonly called a “chiller” by those skilled in the art, in the example of [Fig.l]. It is more generally a liquid / liquid type heat exchanger capable of exchanging calories between two separate liquids, one of the liquids being able to change phase to become gaseous, or vice versa, under the effect of the heat exchange.

[0093] The first heat exchanger 14 arranged to exchange calories with a first heat transfer fluid is here an internal condenser of a ventilation device 56 for interior air in the passenger compartment of the vehicle. Thus, said first heat transfer fluid is in this example an internal air flow Fi blown into the passenger compartment of the vehicle.

[0094] The first heat exchanger 14 is more generally a heat exchanger operating as a condenser or cooler of the refrigerant fluid.

[0095] The second heat exchanger 16 arranged to exchange calories with the second heat transfer fluid, is here a condenser on the front face of the vehicle. second heat transfer fluid is therefore in this example an external air flow Fe at the front of the vehicle. More generally, the second heat exchanger 16 is a heat exchanger arranged to act as a condenser or cooler of the refrigerant fluid.

[0096] Advantageously, said main loop further comprises a sub-cooling pass. The first refrigerant storage device 18 is here integrated into the second heat exchanger 16, which comprises downstream of said refrigerant sub-cooling pass. Such an example of a second heat exchanger 16 is detailed below in relation to the third aspect of the invention and [Fig. 16]. Such a configuration of a second exchanger 16 also applies to the first and / or second aspects of the invention.

[0097] The refrigerant circuit 10 further comprises a first bypass branch 24 between a first bypass point 26 located on the main loop LP between the first heat exchanger 14 and the second heat exchanger 16 and a first junction point 28 located on the main loop LP between the first refrigerant storage device 18 and the first expansion member 20.

[0098] The first bypass branch 24 makes it possible to short-circuit the second heat exchanger 16 and thus bring the refrigerant fluid to the two-fluid heat exchanger 22 as will be explained in more detail further below with reference to [Fig.3].

[0099] Said main refrigerant loop LP also comprises a second refrigerant storage device 30 between the first heat exchanger 14 and said first branch point 26.

[0100] The second refrigerant storage device 30 is commonly called a “bottle”. It may include a refrigerant desiccant. It provides a gas / liquid separation function so that the outgoing fluid is liquid.

[0101] The third heat transfer fluid circuit 11 comprises, in addition to said two-fluid heat exchanger 22, a fourth heat exchanger 32 arranged to exchange calories, directly or indirectly, with a fourth heat transfer fluid.

[0102] The fourth heat exchanger 32 is here an (“external”) radiator on the front face of the vehicle, the fourth heat transfer fluid being in this example an external air flow (Fe) on the front face of the vehicle. It is more generally a heat exchanger for cooling or heating the third heat transfer fluid, i.e. for cooling or heating the heat transfer liquid circulating in the fourth heat exchanger 32.

[0103] The third heat transfer fluid is here for example glycolated water or another heat transfer liquid of any suitable type.

[0104] The refrigerant circuit 10 further comprises a second refrigerant bypass branch 34 between a second bypass point 36 and a second junction point 38, the second bypass point 34 being located on the main loop LP between the second heat exchanger 26 and the first expansion member 20, for example between the first junction point 26 and the first expansion member 20, and the second junction point 38 being located on the main loop LP between the two-fluid heat exchanger 22 and the compressor 12.

[0105] The second bypass branch 34 comprises, in the direction of circulation of the refrigerant fluid, a second expansion member 40 and a fifth heat exchanger 42 arranged to exchange calories, directly or indirectly, with a fifth heat transfer fluid, in particular so that said fifth heat exchanger 42 can operate as a refrigerant fluid evaporator when the system is in air conditioning mode and in dehumidification mode, the fifth heat transfer fluid being in this example an internal air flow (Fi) blown into the passenger compartment of the vehicle. Indeed, the fifth heat exchanger 42 is typically an evaporator integrated into the interior air ventilation device 56. It is more generally a heat exchanger for evaporating the refrigerant fluid circulating within it.

[0106] It should be noted that, according to another approach to the same circuit, the fifth heat exchanger 42 is considered to be the cooling heat exchanger according to the invention and, with the second expansion member 40, they are considered to be on the main loop in place of the two-fluid exchanger 22 and the first expansion member 20. Said two-fluid exchanger 22 and the first expansion member 20 are then considered to be on the second bypass branch.

[0107] The second expansion member 40 is typically an electronic expansion valve, or electronic “expansion valve”.

[0108] The refrigerant circuit 10 further comprises a third refrigerant bypass branch 44 between a third bypass point 46 and a third junction point 48, the third bypass point 46 being located on the main loop LP between the first refrigerant storage device 18 and the first junction point 28 of the first bypass branch 24, and the third junction point 48 being located on the second bypass branch 34 between the fifth heat exchanger 42 and the second junction point 38 of the second bypass branch 34.

[0109] The refrigerant circuit 10 is also equipped with different types of valves or flaps.

[0110] The refrigerant circuit 10 comprises a first three-way valve 33 connecting the second refrigerant storage device 30, the second heat exchanger heat 16 and the first bypass branch 24 at the first junction point 26. This first three-way valve 33 makes it possible to circulate the refrigerant fluid from the first heat exchanger 14 to the second heat exchanger 16 or to the first bypass branch 24. Alternatively, these are two stop valves respectively on one and the other of the branches downstream of the first bypass point 26.

[0111] The third branch of bypass 44 comprises a stop valve 50, but does not comprise, in this example, a heat exchanger.

[0112] The second bypass branch 34 comprises a first non-return valve 52 located between the first junction point of the second bypass branch 34 and the third junction point 48 of the third bypass branch 44.

[0113] The main loop LP comprises a second non-return valve 54 located between the first refrigerant storage device 18 and the first junction point 28 of the first bypass branch 24, more precisely between the third bypass point 46 of the third bypass branch 44 and the first junction point 28 of the first bypass branch 24.

[0114] The main circuit operating modes of [Fig.l] will be explained in more detail with reference to Figures 3 to 5.

[0115] [Fig.2] illustrates as an example a possible heat transfer fluid circuit for said third heat transfer fluid passing through said two-fluid heat exchanger 22.

[0116] The third heat transfer fluid circuit 11 comprises a first branch B1 for circulating the heat transfer fluid comprising a first pump 58 and the two-fluid heat exchanger 22. The third heat transfer fluid circuit 11 also comprises a so-called “external” branch BE for circulating the third heat transfer fluid, said external branch BE comprising said fourth heat exchanger (32).

[0117] In order to form a circulation loop of the third heat transfer fluid, an upstream end of said external branch BE is connected to a downstream end of said first branch B1 and a downstream end of said external branch being connected to an upstream end of said first branch B1. In this way, when the first pump 58 is active, the heat transfer liquid circulates through the two-fluid heat exchanger 22 and through the fifth heat exchanger 32, which allows passive heating of the heat transfer liquid and thus passive heating of the refrigerant fluid passing through the two-fluid heat exchanger.

[0118] The third heat transfer fluid circuit 11 also comprises a second branch B2 for circulating the third heat transfer fluid, an upstream end of the second circulation branch B2 being connected to a downstream end of said first branch B1, for example downstream of the two-fluid heat exchanger 22, and a downstream end of said second branch B2 being connected to an upstream end of said first branch B1, so as to together form a circulation loop. of third heat transfer fluid.

[0119] Said second branch B2 preferably does not include any device capable of significantly modifying the quantity of heat accumulated by the first heat transfer fluid.

[0120] This arrangement of the first and second branches B1, B2 allows the circulation of the third heat transfer fluid in a loop in the first pump 58, the electric heating device 60 and in the bifluid heat exchanger 22, which allows this active heating of the refrigerant fluid when the electric heating device 60 is active. Preferably the electric heating device 60 is directly upstream of the bifluid heat exchanger 22. This mode of heating the refrigerant fluid is useful for example when the outside temperature is too cold to heat the refrigerant fluid. This minimum temperature will depend on the type of refrigerant used.

[0121] The third heat transfer fluid circuit 11 comprises a third branch B3 and a fourth branch B4 for circulation of the third heat transfer fluid.

[0122] The third branch B3 comprises a second pump 62 and a sixth heat exchanger 66, for example of the “electrical machines” type for exchanging heat with electrical machines of the vehicle.

[0123] The fourth branch B4 comprises a seventh heat exchanger 68, for example of the “battery” type for exchanging heat with batteries of the vehicle, an upstream end of said fourth branch B4 being connected to a downstream end of said first branch B1 and a downstream end of said fourth branch B4 being connected to an upstream end of said first branch B1 by a fifth branch B5 for circulating the third heat transfer fluid, in particular so as to form together a heat transfer fluid circulation loop, for example so as to allow the electric heating device 60 to heat the third heat transfer fluid circulating in the seventh heat exchanger 68, or for example so as to allow, the two-fluid heat exchanger 22 being active, to cool the third heat transfer fluid circulating in the seventh heat exchanger 68 and thus cool the batteries of the vehicle.

[0124] An upstream end of the fourth branch B4 is here connected to a downstream end of said third branch B3, and a downstream end of said fourth branch B4 is connected to an upstream end of said third branch B3, so as to form together a circulation loop of third heat transfer fluid, for example so as to allow the third heat transfer fluid circulating in the seventh heat exchanger 68 to be heated by recovering heat in the sixth heat exchanger 66, i.e. in the electrical machines of the vehicle (electric motor or power electronics for example).

[0125] The third heat transfer fluid circuit 11 also comprises a sixth branch B6 for circulation of the third heat transfer fluid, an upstream end of said sixth branch being connected to a downstream end of said third branch B3 and a downstream end of said sixth branch B6 being connected to an upstream end of said external branch BE, in particular so that said third branch B3, said sixth branch B6 and said external branch BE together form a circulation loop for the third heat transfer fluid, in particular so as to allow the “passive” cooling of the third heat transfer fluid circulating in said sixth heat exchanger (66).

[0126] Furthermore, the heat transfer fluid circuit 11 here comprises different valves or valves to direct the circulation of the heat transfer fluid.

[0127] The third heat transfer fluid circuit 11 comprises a “second” three-way valve 74, a “third” three-way valve 76 and a “fourth” three-way valve 78.

[0128] Said second three-way valve 74 connects a downstream end of said first branch B1, an upstream end of said second branch B2 and an upstream end of said external branch BE, configured to allow the circulation of the third heat transfer fluid between said first branch B1 and said second branch B2 or between said first branch B1 and said external branch BE, the first branch B1 being for example connected via a seventh branch B7.

[0129] The third three-way valve 76 connects a downstream end of said fourth branch B4, an upstream end of said fifth branch B5 and an upstream end of said third branch B3, configured to allow the circulation of the third heat transfer fluid between said fourth branch B4 and said fifth branch B5 or between said fourth branch B4 and said third branch B3.

[0130] The fourth three-way valve 78 connects a downstream end of said third branch B3, an upstream end of said fourth branch B4 and an upstream end of said sixth branch B6 to allow the circulation of the third heat transfer fluid between said third branch B3 and said fourth branch B4 or between said third branch B3 and said sixth branch B6.

[0131] Furthermore, a “third” non-return valve 80 is arranged on an eighth branch B8 connecting an upstream end of said first branch B1 and a downstream end of said fourth branch B4, downstream of a fourth branch point 82 to said seventh branch B7 and upstream of a fourth junction point 84 of said third branch B3 to said fourth branch B4. This non-return valve 80 allows for example the circulation in a loop in the second pump 62, the sixth heat exchanger 66 and the seventh heat exchanger 68, while also allowing the circulation of heat transfer fluid from the first branch B1 to the fourth branch B4.

[0132] The circulation of heat transfer fluid from the first branch B1 to the seventh branch B7 is here obtained by closing the downstream end of the fourth branch B4 at the level of said third three-way valve 76.

[0133] It should also be noted that the third heat transfer fluid circuit 11 comprises an expansion tank 72, located on said external branch BE. Alternatively, the expansion tank is located elsewhere in the third heat transfer fluid circuit 11.

[0134] Different operating modes of the reversible air conditioning circuit are illustrated with reference to Figures 3 to 5.

[0135] In [Fig.3], the refrigerant circuit 10 operates in a first heat pump mode.

[0136] The first three-way valve 33 closes the circulation to said second heat exchanger 16 and ensures the circulation from the first heat exchanger 14 to the first bypass branch 24. The second expansion member 40 is closed, preventing circulation to said fifth heat exchanger 42. The first expansion member 20 is, however, partially open, so as to subject the refrigerant fluid to expansion before arriving in said two-fluid heat exchanger 22. The refrigerant fluid is then led to the compressor 12 due to the non-return valve 52. The stop valve 50 is opened if necessary to bring charge from the condenser to the active loop.

[0137] The refrigerant circuit 10 thus forms a closed loop of refrigerant circulating successively in the compressor 12, in the first heat exchanger 14 operating as a refrigerant condenser or cooler, in the second storage device 30 of the bottle type, in the first expansion member 20, and in the two-fluid heat exchanger 22 operating as a refrigerant evaporator, thus heating the refrigerant. To bring this necessary heat to the refrigerant, the third heat transfer fluid is for example set in motion towards the external radiator 32 to capture calories in the external air flow Fe, as previously explained above with reference to [Fig.2].

[0138] To summarize, this first heat pump mode uses the chiller 22 (“bidluid heat exchanger”) for cooling the batteries as an evaporator.

[0139] In a battery cooling mode illustrated in [Fig.4], the first three-way valve 33 closes the circulation to the first bypass branch 24 and ensures the circulation from the first heat exchanger 14 to said second heat exchanger 16. The stop valve 50 is closed. The second expansion member 40 is closed and the first expansion member 20 is partially open to achieve expansion of the refrigerant fluid.

[0140] The refrigerant circuit 10 thus forms an active refrigerant loop. circulating successively through the compressor 12, the first heat exchanger 14 operating as a refrigerant fluid condenser or cooler, in the second bottle-type storage device 30, in the second heat exchanger 16 operating as a refrigerant fluid condenser or cooler, in the first expansion member 20, and in the two-fluid heat exchanger 22 operating as a refrigerant fluid evaporator, thus heating the refrigerant fluid. The refrigerant fluid thus cools the third heat transfer fluid, which makes it possible to cool the batteries by circulating the third heat transfer fluid in the seventh “battery” heat exchanger 68. The evacuation of the heat from the batteries jointly in the first heat exchanger 1' and in the second heat exchanger 16 makes it possible to maximize the cooling power of the batteries.

[0141] In a mode of operation not shown, which differs from the mode of [Fig.2] by the fact that the first expansion member 20 is closed and the second expansion member 40 partially open so as to evaporate the refrigerant fluid in the fifth heat exchanger 42, a mode of air conditioning of the passenger compartment is obtained with significant refrigeration power.

[0142] In another operating mode not shown, which differs from the mode of [Fig.2] by the fact that both the first expansion member 20 and the second expansion member 40 are partially open so as to evaporate the refrigerant fluid in the two-fluid heat exchanger 22 and in the fifth heat exchanger 42, a combined mode of cooling the batteries and air conditioning the passenger compartment is obtained.

[0143] In [Fig.5] a combined dehumidification and heat pump mode is illustrated.

[0144] The first three-way valve closes the circulation to the first bypass branch 24 and ensures the circulation from the first heat exchanger 14 to the second heat exchanger 16. The first expansion member 20 and the second expansion member 40 are partially open so as to expand the refrigerant fluid and so that the two-fluid heat exchanger 22 and said fifth heat exchanger 42 operate as a refrigerant fluid evaporator.

[0145] The shutoff valve 50 is opened if necessary to bring charge from the condenser to the active loop.

[0146] The first heat exchanger 14 and the second heat exchanger 16 both operate as a refrigerant condenser (or cooler). As in the operating mode of [Fig. 3], the two-fluid heat exchanger captures heat from the refrigerant, which heat is returned to the first heat exchanger 14 to heat the passenger compartment of the vehicle. Furthermore, the fifth heat exchanger 42 makes it possible to dehumidify the air by lowering the temperature temperature of the internal air passing through it and condensing part of the humidity present in this internal air.

[0147] Another dehumidification mode not shown simply differs from the mode of [Fig.5] in that the first expansion member 20 is closed, which prevents the circulation of refrigerant fluid in the bifluid heat exchanger 22 (or “chiller”).

[0148] [Fig.6] illustrates a second embodiment of a refrigerant circuit according to another aspect of the invention, which simply differs from the circuit of [Fig.l] in that it comprises a third expansion member 70 located between said first branch point 26 of said first branch branch 24 and said second heat exchanger 16.

[0149] In this example, said third expansion member 70 is integrated into the first three-way valve (33). Alternatively, the third expansion member 70 is independent of the first three-way valve 26.

[0150] The third expansion member 70 is of any suitable type. It is, for example, a device of an electronic fluid expansion valve or “electronic expander”.

[0151] The third expansion member 70 makes it possible to subject the refrigerant fluid arriving in the second heat exchanger 16 to expansion and thus to operate the second heat exchanger as a refrigerant fluid evaporator while circulating in the same direction in said second heat exchanger, compared to the direction of circulation in which the second heat exchanger 16 is used as a refrigerant fluid condenser (or cooler).

[0152] so that said second heat exchanger 16 can operate as a refrigerant fluid evaporator when the system is in heat pump mode, for example jointly or not with the bifluid heat exchanger (22) also operating, for example, as a refrigerant fluid evaporator when the system is in heat pump mode.

[0153] The circuit of [Fig.6] enables the illustrated modes of operation described with reference to Figures 3 to 5 and also enables other modes of operation which are described with reference to Figures 7 to 9.

[0154] In [Fig.7], the first three-way valve 33 closes the first branch of rivation 24 and allows the circulation of refrigerant fluid from the first heat exchanger to the second heat exchanger 16. The third expansion member 70 is partially open. The first expansion member 20 and the second expansion member 40 are closed. The stop valve 50 is open. The refrigerant circuit thus ensures circulation of refrigerant fluid in a loop of the compressor 12, to the first heat exchanger 141st second heat exchanger 16, then back to the compressor. The first heat exchanger 16 operates in refrigerant condenser (or cooler) while the second heat exchanger 16 operates as a refrigerant evaporator. This is therefore an alternative heat pump mode to the heat pump mode in which the bifluid heat exchanger 22 is used as an evaporator.

[0155] [Fig.8] illustrates another heat pump mode corresponding to the combination of the operating modes of Figures 3 and 7

[0156] The refrigerant fluid circuit 10 of [Fig.8] compared to [Fig.7] is that said first expansion member 20 is partially open so as to allow the circulation of refrigerant fluid towards the bifluid heat exchanger 22 while subjecting the refrigerant fluid water to expansion in said first expansion member 20 and in that the stop valve 50 is closed.

[0157] The refrigerant circuit 10 thus forms a refrigerant circulation loop from the compressor 12 to the first heat exchanger 14 then to the second heat exchanger 16 before circulating to the two-fluid heat exchanger 22.

[0158] The first heat exchanger 1' operates as a condenser (or refrigerant fluid cooler), while the second heat exchanger 14 and the bifluid heat exchanger 22 operate as an evaporator.

[0159] More particularly, the second heat exchanger 16 operates as an evaporator on the outside air Fe and the two-fluid heat exchanger 22 operates as an evaporator on the third heat transfer fluid, which, as explained with reference to [Fig.2], is heated passively by circulating in the external radiator 32 (or fourth heat exchanger) or actively by circulating in the electric heating device 60.

[0160] The embodiment of [Fig.8] makes it possible to have increased heating power in heat pump mode.

[0161] Finally, [Fig. 9] illustrates an operating mode combining the increased power heat pump mode of [Fig. 8] with a dehumidification mode. The refrigerant circuit 10 differs from [Fig. 8] in that the second expansion member 40 is partially open, so as to allow the circulation of refrigerant to the fifth heat exchanger 42 while subjecting the refrigerant to water expansion in said second expansion member. In this way, a portion of the refrigerant coming from the second exchanger 16 branches off to the first expansion member 20 and the dual-fluid heat exchanger 22 and another portion of the refrigerant arriving at the second branch point 36 flows to the second expansion member 40 then to the fifth heat exchanger 42 before returning to the compressor 12.The fifth heat exchanger 42 thus operates as a refrigerant fluid evaporator in parallel with the two-fluid heat exchanger 22, which . also functions as a refrigerant fluid evaporator 22. The interior air ventilation device 16 thus dehumidifies the internal air fluid which is first cooled in the fifth heat exchanger 42 before being reheated in said first heat exchanger 16.

[0162] As illustrated in Figures 10 to 15, a third aspect of the invention will now be discussed by developing its differences with the previous embodiments.

[0163] According to this third aspect of the invention, as is the case in the previous aspects, said system is configured to operate in cooling and / or air conditioning mode by cooling the fluid to be cooled, namely here the heat transfer fluid of the second circuit 11 and / or the internal air flow Fi, passing through said cooling exchanger 22, 42, using said refrigerant fluid running through said main loop LP, said refrigerant fluid dissipating calories at said second exchanger 16, passed through in a first direction by said refrigerant fluid and operating as a condenser or gas cooler, in an optimized manner.

[0164] Said system is further configured to operate in heat pump mode by heating said fluid to be cooled using said refrigerant, said refrigerant taking calories at said second exchanger 16 then coming, unlike the previous aspects of the invention, from said first bypass branch 24. In this way, the refrigerant circulates in said second exchanger 16 in the opposite direction to that in which it circulates in the main circuit PL and the second exchanger also operates as an evaporator or gas heater in an optimized manner.

[0165] In other words, according to this third aspect of the invention, the second heat exchanger 16 is configured to act alternately as a condenser or cooler of the refrigerant fluid or as an evaporator or heater of the refrigerant fluid, this being optimized in each case thanks to the inversion of the circulation of the refrigerant fluid.

[0166] To enable certain operating modes, in particular in relation to this circulation inversion, said system here comprises a fourth expansion member 90. Said fourth expansion member 90 is located, for example, between said second exchanger 16 and the first junction point 28 according to the direction of circulation of the refrigerant fluid in said main loop.

[0167] Still according to this third aspect of the invention, it can be seen that the third branch branch 44 is located differently than in the previous aspects. Indeed, the third branch point 46 is located on the main loop between said first branch point 26 and said second exchanger 16. On the other hand, the third junction point 48 remains located on the second branch branch 34 between the fifth heat exchanger 42 and the second junction point 38 of the second branch of derivation 34.

[0168] Said system optionally comprises an exchanger, called internal, 200, configured to allow a heat exchange between the refrigerant fluid and itself. The refrigerant fluid passes through said internal exchanger 200 according to respective passes, while it is at different pressure levels in each pass, before passing again into the compressor 12. One 202a of the passes, namely the high pressure pass, is, for example, in the main loop downstream of said fourth expansion member 90 and upstream of said first junction point 28 according to the direction of circulation of the fluid in said main loop. Another 202b of the passes, namely the low pressure pass, is, for example, in the third bypass branch 44.

[0169] As illustrated in [Fig. 16], said second exchanger 16 comprises a heat exchange bundle 100. Said bundle 100 comprises, for example, a plurality of tubes for circulating said refrigerant fluid. They are advantageously parallel to each other and connected by secondary exchange surfaces such as corrugated spacers. Said tubes open through opposite longitudinal ends into collectors. Only a first 102 of said collectors is illustrated here.

[0170] Said first storage device 18 here comprises a bottle 104, secured to said bundle 100. Said bottle 104 is, for example, fixed to said first collector 102. It extends parallel to said first collector 102.

[0171] Said bundle is provided with one or more first passes 106 for circulation of the refrigerant fluid, located upstream of said first storage device 18 in said main loop. Said bundle 100 further comprises said subcooling pass, here referenced 108.

[0172] According to all aspects of the invention, in said first pass(es), in condenser mode, the refrigerant fluid changes phase to pass from a gaseous phase to a liquid phase. It then passes into the bottle 104 where any remaining gas bubbles are isolated and enter the subcooling pass in the entirely liquid phase. It then undergoes forced subcooling. According to the third aspect of the invention, in evaporator mode, it circulates in the opposite direction. The circulation in both directions of the refrigerant fluid in said second exchanger 16 is here materialized by the double inlet / outlet arrows 120a, 120b.

[0173] In the illustrated embodiment, said second exchanger comprises a first passage 110 between said first collector 102 and said bottle 104 for the refrigerant fluid, coming from or towards said first pass(es) 106, and / or a second passage 112 for the refrigerant fluid, coming from or towards said subcooling pass 108. According to this configuration, it is understood that the direction of circulation of the refrigerant fluid in said bottle 104 is also reversed depending on the direction of circulation of the refrigerant fluid in said second exchanger 16.

[0174] Preferably, an exchange surface of said first passes 106 represents at least two thirds of a total exchange surface of said bundle 100. In other words, an exchange surface of said sub-cooling pass 108 represents less than one third of said total exchange surface of the bundle 100.

[0175] As already mentioned, said system comprises a filter and / or a desiccant for said refrigerant fluid. In the previous embodiments, said filter and / or said desiccant are located in the bottle. In the present embodiment, the circulation in the bottle 18 is free, that is to say with the minimum of pressure losses and said filter and / or said desiccant are on the contrary located at another point of the refrigerant fluid circuit, advantageously along its main loop, even more advantageously at the level of said second storage device 30.

[0176] For the rest, the characteristics of the first and / or second aspects of the invention are repeated.

[0177] Different operating modes of this third operating mode will now be described. However, they are not exhaustive.

[0178] As illustrated in [Fig.10], said refrigerant circuit is configured to operate in cooling and / or air conditioning mode, by transferring calories taken from the heat transfer fluid of the second circuit 11 and / or from the internal air flow Fi to the refrigerant using said two-fluid exchanger 22 and / or said fifth exchanger 42. It is thus possible to cool the heat transfer fluid of the second circuit 11 and, consequently, the batteries, and / or said internal air flow Fi. Said refrigerant circuit is further configured to evacuate the calories taken by the refrigerant from the external air flow Fe using said second exchanger 16, operating as a condenser or gas cooler.

[0179] In this operating mode, starting from the compressor 12, the refrigerant passes into the first exchanger 14, which is designed to be inactive, i.e. without heat exchange with the internal air flow Fi. It then passes through the second storage device 30 and the first three-way valve 33, the outlet of which to the first bypass branch 24 is closed. The third expansion member 70 is inactive, i.e. open so as not to operate any expansion. The refrigerant circulates downstream through the second exchanger 16, passing through the first pass(es), the first storage device 18 and then the subcooling pass. Said second exchanger 16 operates as a condenser or gas cooler, in an optimized manner.Said refrigerant fluid then passes through the high pressure pass 202a of the internal exchanger, without exchanging heat with the low pressure pass 202b since the refrigerant fluid then does not circulate in said third bypass branch 44. It then passes through, on the one hand, the first expansion member 20, designed to be active, that is to say operating an expansion, and the two-fluid heat exchanger 22, operating as an evaporator or re. gas heater and / or, on the other hand, the second expansion member 40, provided active, i.e. operating an expansion, and the fifth heat exchanger 42, operating as an evaporator and / or gas heater. It thus cools the heat transfer fluid of the second circuit 11 and / or the internal air flow Fi. The refrigerant fluid then returns to the compressor 12.

[0180] As illustrated in [Fig.l 1], said refrigerant circuit is configured to operate in a first heat pump and / or heat recovery mode, by transferring calories taken from the heat transfer fluid of the second circuit 11 and / or from the external air flow Fe to the refrigerant using said two-fluid exchanger 22 and / or said second heat exchanger 16, operating as an evaporator or gas heater. It is thus possible to use the calories released by the battery and / or available in the ambient air to heat the internal air flow Fi via said refrigerant circuit and the first exchanger 14.

[0181] In this operating mode, starting from the compressor 12, the refrigerant fluid passes into the first exchanger 14 and heats the internal air flow Fi. It then passes through the second storage device 30 and the first three-way valve 33, the outlet of which towards the downstream part of the main loop is closed. It circulates downstream via the first bypass branch 24 to arrive at the first junction point 28.

[0182] In heat pump mode only, according to a first path, the refrigerant passes through the high pressure pass 202a of the internal exchanger 202 then the fourth expansion member 90, provided active, and the second exchanger 16 passing through the subcooling pass, the first storage device 18 then the first pass(es). It thus passes through said second heat exchanger 16 in a direction opposite to that of the previous operating mode. Said second exchanger then operates as an evaporator or gas heater, in an optimized manner. Said refrigerant thus takes on calories. It takes downstream the third bypass branch 44 and passes through the low pressure pass 202b of the internal exchanger 202 exchanging heat with the high pressure pass 202a.It then joins the second bypass branch at the third junction point 48 then the main loop at the second junction point 38 to return to the compressor 12.

[0183] In heat recovery mode only, along a second path, downstream of the first junction point 28, said refrigerant fluid passes through the first expansion member 20, designed to be active, and the bifluid heat exchanger 22, operating as an evaporator or gas heater. It is thus charged with calories. The refrigerant fluid then returns to the compressor 12 via a final portion of the main loop.

[0184] In the case of joint implementation of the first heat pump mode and the heat recovery mode, as illustrated, the refrigerant fluid separates into two portions at said first junction point 28, each of the portions following respectively the first and second paths mentioned above to then converge at said second junction point 38.

[0185] As illustrated in [Fig.12], said refrigerant circuit is configured to operate in a second heat pump mode and in cooling mode, by dissipating calories taken from the heat transfer fluid of the second circuit 11, using said two-fluid exchanger 22, in the internal air flow Fi, using the first exchanger 14. Said refrigerant circuit is further configured to take calories from the external air flow Fe, using the second exchanger 16, operating as an evaporator or gas heater, to transfer them to the refrigerant. It is thus possible to cool said heat transfer fluid of said second circuit 11 and, consequently, the batteries, and to heat the internal air flow Fi, the heating of the latter being reinforced by the calories captured from the external air flow Fe.

[0186] In this operating mode, starting from the compressor 12 and following the main loop, the refrigerant passes into the first exchanger 14, operating as a condenser or gas cooler, to heat the internal air flow Fi. It then passes through the second storage device 30 and the first three-way valve 33, the outlet of which to the first bypass branch 24 is closed. The third expansion member 70 is active and performs a first expansion. The refrigerant circulates downstream through the second exchanger 16 passing through the first pass(es), the first storage device 18 and then the subcooling pass. It thus takes calories from the external air flow Fe, said second exchanger 16 operating as an evaporator or gas heater.It then passes through the high pressure pass 202a of the internal exchanger 202, without exchanging heat with the low pressure pass 202b since the refrigerant fluid then does not circulate in said third bypass branch 44. Said refrigerant fluid then passes through the first expansion member 20, provided active and operating a second expansion, then the bifluid heat exchanger 22, operating as an evaporator or gas heater. It thus cools the heat transfer fluid of the second circuit 11. The refrigerant fluid then returns to the compressor 12.

[0187] As illustrated in [Fig. 13], said refrigerant circuit is configured to operate in a simple dehumidification mode, by exploiting a thermal inertia of the internal air flow Fi, this by taking calories from the internal air flow Fi, using the fifth exchanger 42, and transferring them to said internal air flow Fi, using said first exchanger 14, via said circuit of refrigerant fluid. Said refrigerant fluid circuit is optionally configured to further operate in heat recovery mode by transferring calories taken from the heat transfer fluid of the second circuit 11 to the refrigerant fluid using said two-fluid exchanger 22. It is thus possible to cool said internal air flow Fi to dehumidify it and then to reheat it in order to have an internal air flow Fi that is both dry and hot, the possibility of reheating the air being optionally reinforced by the calories taken from the heat transfer fluid of the second circuit 11.

[0188] In this mode of operation, starting from the compressor 12, the refrigerant fluid passes into the first exchanger 14 which operates as a condenser or gas cooler by exchanging heat with the internal air flow Fi in order to dissipate calories from the refrigerant fluid in said internal air flow Fi and to heat it. It then passes through the second storage device 30 and the first three-way valve 33 whose outlet to the downstream part of the main loop is closed. It circulates downstream through the first bypass branch 24 to arrive at the first junction branch 28.

[0189] Said fourth expansion member 90 being closed, the refrigerant fluid continues downstream towards the second expansion member 40, provided active, and the fifth heat exchanger 42, operating as an evaporator and / or gas heater, or even towards the first expansion member 20, provided active, and the bifluid heat exchanger 22, operating as an evaporator or gas heater. It thus cools the internal air flow Fi to dehumidify it, or even takes calories from the heat transfer fluid of the second circuit 11. The refrigerant fluid then returns to the compressor 12.

[0190] As illustrated in [Fig.14], said refrigerant circuit is configured to operate in a parallel dehumidification mode, on the one hand by exploiting a thermal inertia of the internal air flow Fi, this by taking calories from the internal air flow Fi, using the fifth exchanger 42, and transferring them to said internal air flow Fi, using said first exchanger 14, via said refrigerant circuit, and on the other hand by taking calories from the external air flow Fe to transfer them into the refrigerant via the second exchanger 16 operating as an evaporator or gas heater. It is thus possible to cool said internal air flow Fi to dehumidify it and then to reheat it to have an internal air flow Fi that is both dry and hot, the possibility of reheating the internal air flow Fi being possibly reinforced by the calories taken from the external air flow Fe.

[0191] In this operating mode, starting from the compressor 12, the refrigerant fluid passes into the first exchanger 14 and heats the internal air flow Fi using all of its calories. It then passes through the second storage device 30 and the first three-way valve 33, the outlet of which towards the downstream part of the main loop is closed. It circulates downstream through the first bypass branch 24 to arrive at the first junction point 28. It then splits into two fractions to follow both the first path mentioned above and a third path.

[0192] As already stated, along the first path, the refrigerant passes through the high-pressure pass 202a of the internal exchanger 200 then the fourth expansion member 90, provided to be active, and the second exchanger 16 passing through the subcooling pass, the first storage device 18 then the first pass(es). Said second exchanger 16 then operates as an evaporator or gas heater, in an optimized manner. It thus takes calories from said external air flow Fe. Said refrigerant takes downstream the third bypass branch 44 and passes through the low-pressure pass 202b of the internal exchanger 202 by exchanging heat with the high-pressure pass 202a. It then joins the second bypass branch 34 at the third junction point 48 then the main loop at the second junction point 38 to return to the compressor 2.

[0193] Along the third path, downstream of the first junction point 28, said refrigerant fluid passes through the second expansion member 40, provided to be active, and the fifth heat exchanger 42, operating as an evaporator or gas heater. It thus dries the internal air flow Fe. The refrigerant fluid then returns to the compressor 12, joining the other fraction of refrigerant fluid at said third junction point 48.

[0194] As illustrated in [Fig.15], said refrigerant circuit is configured to operate in series dehumidification mode, or even in cooling mode, by transferring calories taken from the internal air flow Fi, or even from the heat transfer fluid of the second circuit 11, using said fifth exchanger 42, or even said bifluid exchanger 22, to the refrigerant. It is thus possible to dry said internal air flow Fi, or even to cool said heat transfer fluid of said second heat transfer fluid circuit and, consequently, the batteries. Said refrigerant circuit is further configured to evacuate the calories from the refrigerant using said first exchanger 14 to heat said internal air flow Fi which will thus be dry and hot. Said circuit is further configured to take calories from said external air flow Fe via said second exchanger 16 operating as an evaporator or gas heater.The possibility of heating the internal air flow Fi is thus reinforced.

[0195] In this operating mode, starting from the compressor 12, the refrigerant passes into the first exchanger 14, operating as a condenser or gas cooler to heat the internal air flow Fi. The refrigerant then passes through the second storage device 30 and the first three-way valve 33, the outlet of which to the first bypass branch 24 is closed. The third expansion member 70 is active to operate a first expansion and the refrigerant circulates downstream to through the second exchanger 16 via the first pass(es), the first storage device 18 and then the subcooling pass. Said second heat exchanger 16 operates as an evaporator or gas heater by taking calories from the external air flow Fe. The refrigerant fluid continues downstream along the main loop then passes through the fourth expansion member, provided inactive, the internal heat exchanger 200, without heat exchange. Downstream, it passes through the second expansion member 40, provided active to operate a second expansion, and the fifth heat exchanger 42, operating as an evaporator and / or gas heater, or even through the first expansion member 20, provided active to operate another second expansion, and the two-fluid heat exchanger 22, operating as an evaporator or gas heater.In this way, it dries the internal air flow Fe, or even cools the heat transfer fluid of the second circuit 11. The refrigerant fluid then returns to the compressor 12.

Claims

1.

2.

3. Claims Thermal management system of a hybrid or electric vehicle, the thermal management system comprising a reversible air conditioning circuit (10) in which a refrigerant circulates, the reversible air conditioning circuit (10) comprising, in the direction of circulation of the refrigerant, in a main loop (LP) of refrigerant, a compressor (12), a first heat exchanger (14) arranged to exchange calories with a first heat transfer fluid, a second heat exchanger (16) arranged to exchange calories with a second heat transfer fluid, a first storage device (18) for refrigerant, a first expansion member (20, 40) for the refrigerant and a heat exchanger (22, 42), called a cooling heat exchanger,the refrigerant circuit (10) further comprising a first bypass branch (24) between a first bypass point (26) located on the main loop (LP) between the first heat exchanger (14) and the second heat exchanger (16) and a first junction point (28) located on the main loop (LP) between the first refrigerant storage device (18) and the first expansion member (20), said main refrigerant loop (LP) further comprising a second refrigerant storage device (30) between the first heat exchanger (14) and said first bypass point (26)., System according to claim 1 configured to operate alternately, in a first case, in air conditioning mode by cooling a fluid, said to be cooled, passing through said cooling exchanger (22, 42), using said refrigerant flowing through said main loop (LP), said refrigerant dissipating calories at said second exchanger (16), or, in a second case, in heat pump mode by heating said fluid to be cooled using said refrigerant then passing through said first bypass branch (24), said refrigerant taking calories at said second exchanger (16), said system being further configured so that the refrigerant passes through the second exchanger (16) in a first direction in the first case and in the opposite direction in the second case. System according to any one of the preceding claims, in which the first refrigerant storage device (18) is integrated into the second heat exchanger (16), the main loop, in particular the second heat exchanger (16), comprising a sub-cooling pass (108) downstream of the first refrigerant storage device (18).

4. System according to the preceding claim in which said second exchanger (16) comprises a heat exchange bundle (100), said bundle (100) being provided with one or more first passes (106) for circulation of the refrigerant fluid, located upstream of said first storage device (18) in said main loop, said bundle further comprising said subcooling pass (108).

5. System according to the preceding claim in which an exchange surface of said first passes (106) represents at least two thirds of a total exchange surface of said beam (100).

6. A system according to any one of claims 4 or 5 wherein said first storage device comprises a bottle (104), secured to said bundle (100), said bottle (104) being configured so that the circulation of the refrigerant fluid is free inside said bottle (104).

7. System according to any one of the preceding claims in which said cooling exchanger is formed of a two-fluid exchanger (22), arranged jointly on a circuit (11) of a third heat transfer fluid, said circuit (11) of third heat transfer fluid comprising, in addition to said two-fluid heat exchanger (22), a fourth heat exchanger (32) arranged to exchange calories, directly or indirectly, with a fourth heat transfer fluid.

8. System according to any one of the preceding claims, in which the refrigerant circuit (10) further comprises a second refrigerant bypass branch (34) between a second bypass point (36) and a second junction point (38), the second bypass point (36) being located on the main loop (LP) between the second heat exchanger (16) and the first expansion member (20), for example between the first junction point (28) and the first expansion member (20), and the second junction point (38) being located on the main loop (LP) between the two-fluid heat exchanger (22) and the compressor (12), the second bypass branch (34) comprising, in the direction of circulation of the refrigerant, a second expansion member (40) and a fifth heat exchanger (42) arranged to exchange calories, so as to direct or indirect, with a fifth heat transfer fluid, in particular so that said fifth heat exchanger (42) can operate as a refrigerant fluid evaporator when the system is in air conditioning mode and in dehumidification mode, the fifth heat transfer fluid being for example an internal air flow (Fi) blown into the passenger compartment of the vehicle.

9. System according to the preceding claim, in which the refrigerant circuit (10) further comprises a third refrigerant bypass branch (44) between a third bypass point (46) and a third junction point (48).

10. System according to the preceding claim in which the third branch point (46) is located on the main loop (LP) between the first refrigerant storage device (18) and the first junction point (28) of the first branch branch (24).

11. The system of claim 9 wherein said third branch point (46) is located on the main loop between said first branch point (26) and said second exchanger (16).

12. A system according to any one of claims 9 to 11 wherein the third junction point (48) is located on the second bypass branch (34) between the fifth heat exchanger (42) and the second junction point (38) of the second bypass branch (34).

13. System according to any one of the preceding claims, in which said main loop (LP) comprises a third expansion member (70), said third expansion member (70) being located between said first bypass point (34) of said first bypass branch (24) and said second heat exchanger (16), in particular so that said second heat exchanger (16) can operate as a refrigerant fluid evaporator when the system is in heat pump mode, for example jointly or not with the bifluid heat exchanger (22) also operating, for example, as a refrigerant fluid evaporator when the system is in heat pump mode.

14. System according to any one of the preceding claims in which said system comprises a fourth expansion member (90), said fourth expansion member (90) being located between said second exchanger 16 and the first junction point 28 according to the direction of circulation of the refrigerant fluid in said main loop.

15. A method of operating a system according to any one of the preceding claims, wherein, in a first heat pump mode, said first heat exchanger (14) operates as a refrigerant condenser or cooler, the cooling heat exchanger (22, 42) operating as a refrigerant evaporator or heater.

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