A method for derating a target value of a temperature of the air leaving a cabin evaporator in a vehicle with an electric powertrain

Abstract

Method for derating a target value of a temperature of the air leaving a cabin evaporator (EVAP) in a vehicle with an electric powertrain, by means of which it is possible to manage the derating of a thermal cooling power output in favour of the cabin of the vehicle in the case of a complete exploitation of the available thermal cooling power, by maintaining a single refrigeration cycle cooling circuit serving both the cabin and the battery, and always ensuring the best possible conditions in terms of comfort in the cabin and of meeting the thermal conditioning needs - especially the cooling - of the battery in the case of a complete exploitation of the thermal (and electric) cooling power available to these ends.

Description

[0001] "A method for derating a target value of a temperature of the air leaving a cabin evaporator in a vehicle with an electric powertrain"

[0002] ★★★★

[0003] TEXT OF THE DESCRIPTION

[0004] Field of the Invention

[0005] The present invention refers to vehicles with an electric powertrain, specifically to BEVs. In more detail, the invention was developed with reference to vehicles with an electric powertrain supplied by a battery (or by batteries) and comprising a refrigeration cycle cooling circuit for the cabin of the vehicle and one or more refrigeration devices (so-called "chillers") for the thermal conditioning of the battery (or of the batteries) .

[0006] Known Art

[0007] In the vehicles with an electric powertrain (so- called BEVs) provided with a refrigeration cycle cooling circuit with a cabin evaporator for the cabin of the vehicle and one or more chillers for the thermal conditioning of the battery (or of the batteries), the characteristics of the components employed lead to an asymmetric absorption of thermal cooling power between the cabin and the battery. Specifically, a cabin evaporator is inherently less efficient in extracting thermal power from the air with respect to the efficiency of a chiller in extracting thermal power from the heat transfer liquid (specifically a coolant) of the forced- convection cooling circuit of the battery (or of the batteries) with which it is in a heat exchange relationship. It is therefore necessary to control and limit the absorption of thermal cooling power by the chillers, in order to prevent a systematic failure to meet the cooling targets of the cabin. A possible solution may involve a complete duplication of the cooling circuit, thereby meaning a condition wherein the cabin is cooled by a respective refrigeration cycle cooling circuit with a cabin evaporator and a respective first compressor, and the battery is cooled by a respective refrigeration cycle cooling circuit with one or more chillers and a respective second compressor. However, clearly, such a solution does not offer any practical advantage, since it involves the duplication of the circuits (including the duplication of costly components, such as the compressor), the proportional increase of the costs to produce the vehicle, the increase of electric power consumption and the increase of the mass of the vehicle.

[0008] The Applicant has already proposed, as a solution of the problem, a method which is the object of the Italian Industrial Invention Patent Application n. 102023000026508, the teaching whereof regards a method for allocating thermal cooling power while maintaining a single cooling circuit and meeting a target temperature of the air supplied to the cabin, and therefore avoiding duplicating the circuit.

[0009] Nevertheless, the technical problem under consideration is likely to appear again when all the thermal cooling power available for the cooling circuit has been exploited. In this case, the availability of thermal power being exhausted, the distribution of thermal cooling power between the cabin and the battery is again dependent on the physical characteristics of the components (the chillers and the cabin evaporator).

[0010] Object of the Invention

[0011] The invention aims at solving the technical problem outlined in the foregoing. Specifically, the object of the invention is to provide a method for managing a refrigeration cycle thermal conditioning system of a vehicle, in particular a vehicle with an electric powertrain, which enables managing the allocation of thermal cooling power between the cabin and the battery in conditions of total exploitation of the available thermal cooling power, while maintaining a single refrigeration cycle cooling circuit both for the cabin and for the battery.

[0012] Summary of the Invention

[0013] The object of the invention is achieved by means of a method having the features set forth in the claims that follow, which form an integral part of the technical disclosure provided herein in relation to the invention.

[0014] Brief Description of the Figures

[0015] The invention will now be described with reference to the annexed Figures, which are provided by way of non-limiting example only and wherein:

[0016] - Figure 1 shows a general diagram of a cooling circuit wherein it is possible to implement a method according to the invention, and Figures 2 to 5 show aspects of the circuit of Figure 1,

[0017] - Figure 6 shows a flow chart representative of the method according to the invention, and Figures 7, 8 show block diagrams representative of the method according to the invention,

[0018] - Figures 9 to 12 show aspects of the implementation of the method according to the invention.

[0019] Detailed Description

[0020] Figure 1 schematically shows the general structure of a cooling circuit CC wherein it is possible to implement a method according to the invention. The circuit CC comprises an electrically operated compressor EAC, the delivery port whereof is in fluid communication with the inlet of a condenser CNDS. The condenser CNDS is in a heat exchange relationship with an air flow rate IAIR CNDS which is supplied partly by a fan F arranged downstream of a set of radiating elements comprising the condenser CNDS and the radiator RAD (the latter being arranged downstream of the condenser CNDS and upstream of the fan F), and partly by the movement of the vehicle. The radiator RAD is part of a cooling circuit of traction elements of the vehicle powertrain, which comprise one or more electric traction motors, the respective transmissions connecting each motor to one or more corresponding wheels of the vehicle, and the transmission oils. The cooling circuit comprising the radiator RAD is traversed by a coolant flow rate which is provided by a circulation pump P_RAD. The sections of the circuit under consideration other than the pump P_RAD, the radiator RAD and the fan F are not shown, as the circuit is per se known.

[0021] The outlet of the condenser CNDS is in fluid communication with a first circuit node N1 wherefrom two circuit branches depart, a first branch being directed towards the inlet of a cabin evaporator EVAP and a second branch being directed to a second circuit node N2, downstream whereof the second circuit branch divides into a third and a fourth circuit branch directed to the inlet of a first refrigeration device (specifically a first chiller) CHL1 and of a second refrigeration device (specifically a second chiller) CHL2.

[0022] The cabin evaporator EVAP is in a heat exchange relationship with a cabin air flow rate mAiRCAB EVAP, which is processed and sent to the evaporator EVAP (and therefore supplied to the cabin) by means of a cabin blower BL.

[0023] Each chiller CHL1 and CHL2 comprises a respective battery evaporator EV_B1, EV_B2 (which receives the refrigerant fluid flowing in the circuit CC) in a heat exchange relationship with a heat transfer fluid, specifically a coolant flowing in a battery cooling circuit of the one or more batteries of the electric powertrain. By way of non-limiting example only, Figure 1 shows two cooling circuits of a high-voltage battery BATT which supplies one or more electric traction motors of the vehicle, wherein a first cooling circuit CL_B1 is in a heat exchange relationship with the evaporator EV_B1 of the chiller CHL1 and comprises a first circulation pump CPI which processes a first coolant flow rate itcLN CHLIZ and a second cooling circuit CL_B2 is in a heat exchange relationship with the evaporator EV_B2 of the chiller CHL2 and comprises a second circulation pump CPI which processes a second coolant flow rate mCLN CHL2• The flow rates mCLN CHLI and mCLN CHL2 are in a heat exchange relationship with the battery BATT for the thermal conditioning thereof, and may be available singularly or together as a function of the chillers which are simultaneously active. Moreover, it is possible to envisage a single cooling circuit in common to both chillers CHLI, CHL2, i.e. a single circulation pump, either keeping the chillers CHLI, CHL2 always active or deactivating one of them (in this case, there will be no heat exchange between the evaporator of the deactivated chiller and the battery cooling circuit), as well as a single chiller with a single battery cooling circuit.

[0024] Upstream of the evaporator EVAP there is arranged an expansion / lamination valve TXV_EVAP, and upstream of the battery evaporators of the chillers CHLI and CHL2 there are arranged respective expansion valves TXV_CHL1 and TXV_CHL2. The expansion / lamination valves enable - by varying the respective hydraulic resistance as a function of the coolant flow rate (which is in the liquid phase while traversing them - in Figure 1 the valves are represented as variable hydraulic resistances) - regulating the pressure of the refrigerant fluid at the inlet of the evaporator EVAP and of the battery evaporators EV_B1, EV_B2 of the chillers CHLI and CHL2, so as to enable a complete evaporation of the refrigerant fluid therein, and to avoid the inlet into the compressor EAC of a biphasic flow rate (liquid + vapour).

[0025] Upstream of each of the valves TXV_EVAP, TXV_CHL1, TXV_CHL2 - i.e. upstream of the respective evaporation devices (the evaporator EVAP and the battery evaporators of the chillers CHL1, CHL2), there are arranged shut-off valves SV_EVAP, SV_CHL1, SV_CHL2, respectively. Alternatively, the shut-off valves SV_EVAP, SV_CHL1, SV_CHL2 may be arranged between the corresponding valve TXV_EVAP, TXV_CHL1, TXV_CHL2 and - respectively - the cabin evaporator EVAP, the battery evaporator of the chiller CHL1 and the battery evaporator of the chiller CHL2 (in other words, the essential point is that they be located upstream of, respectively, the evaporator EVAP and the battery evaporators of the chillers CHL1 and CHL2). Each of the shut-off valves SV_EVAP, SV_CHL1, SV_CHL2 comprises a first open operating condition and a second closed operating condition, and they are normally in the open operating condition. The function of each of them is to exclude from the circuit CC the circuit branch downstream thereof, i.e. to exclude the evaporator EVAP and one or both battery evaporators of the chillers CHL1 and CHL2 according to needs (thereby deactivating the respective chiller).

[0026] The outlet of the chillers CHL1 and CHL2 (i.e. of the battery evaporators EV_B1, EV_B2 of the chillers CHL1, CHL2) converges into a third circuit node N3 and into a single fifth circuit branch which converges, together with the section of the first circuit branch departing from the outlet of the cabin evaporator EVAP, into a fourth circuit node N4, downstream whereof the cooling circuit CC closes at the intake port of the compressor EAC.

[0027] The compressor EAC sends into the circuit CC an overall refrigerant flow rate mRFRTOT in the vapour phase. The flow rate mRFRTOT traverses the condenser, converts into the liquid phase and reaches the node Nl, wherefrom it is split among the cabin evaporator EVAP (flow rate IRFRCABEVAP) and the battery evaporators EV_B1, EV_B2 of the chillers CHL1 and CHL2 (thRFR CHL globally entering the node N2, being split as mRFRCHLI for the evaporator EV_B1 and mRFRCHL2 for the evaporator EV_B2). The flow rates IRFR CAB EVAP and mRFR CHL are subjected to evaporation (at substantially constant pressure) within the battery evaporators EV_B1, EV_B2 of the chillers CHLI and CHL2 and of the cabin evaporator EVAP, thereby cooling the coolant of the one or more batteries and the cabin air, respectively. The flow rates rhRFRCAB EVAP and rhRFRCHL in the vapour phase are mixed at the node N4 into the flow rate rhRFRTOT, which is drawn in again by the compressor EAC to re-enter the circuit CC.

[0028] As a general premise, every reference to a "flow rate" in the present description is to be construed as a reference to a mass flow rate, as indicated by the notation rh for all the flow rates.

[0029] Again, as a general premise, every time the present description refers to a "battery" (also in phrases such as "battery heater"), this is to be construed as a high- voltage battery of the vehicle (in particular of the powertrain of the vehicle) which supplies one or more electric traction motors of the powertrain of the vehicle, unless otherwise specified.

[0030] Figures 2, 3, 4, 5 show in more detail some characteristics of the chillers CHLI and CHL2 and of the evaporator EVAP, specifically:

[0031] - each chiller CHLI and CHL2 processes a refrigerant fluid flow rate rhRFRCHLI and rhRFR CHL2 respectively through the battery evaporators EV_B1 and EV_B2, with mRFRCHLI + mRFR_GHL2 = liiRFR-CHL, and a coolant flow rate mCLN_cHLi and riicLN CHL2z respectively. In the diagram of Figure 1, the flow rates mCLN CHLI and mCLN CHL2 depend on the rotational speeds CPl_n and CP2_n of the pumps CPI and CP2, respectively (Figure 3 - the flow rates depend on the rotational speed of the circulation pump also in the case of a single coolant circuit and of a single circulation pump for both chillers) and they enter the chillers CHLI, CHL2 through respective inlet ports CHL1_IN, CHL2_IN (each being provided with a coolant temperature sensor TS_CLN_IN); then, they leave through outlet ports CHL1_OUT, CHL2_OUT (each being provided with a coolant temperature sensor TS_CLN_OUT), respectively;

[0032] - the cabin evaporator EVAP (Figure 5) processes the refrigerant fluid flow rate mRFRCAB EVAP and it is impinged upon by the cabin air flow rate mAiRCAB EVAP, which impinges upon the evaporator EVAP at an inlet section EVAP_IN and leaves it at an outlet section EVAP_OUT, being in a heat exchange relationship with the flow rate KIRER CAB EVAP in the transit from EVAP_IN to EVAP_OUT. The flow rate mAiRCAB EVAP depends on the rotational speed BL_n of the cabin blower BL (Figure 5).

[0033] According to the invention, and with reference to the Figures 6 to 8, the method includes:

[0034] - determining (block 2, Figure 6 and block 22, Figure 8) a first derated target temperature value TEvp_Air_Out_Der_Drv_Tgt Of the Cabin air flOW rate mAlR_CAB_EVAP leaving the cabin evaporator EVAP under conditions other than vehicle charging (Charging_Active = 0) as a function of a nominal target temperature value TEvp Air OutHVAC Tgt of the cabin air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP, of an external ambient temperature TAmt, and preferably as a function of a current driving mode Drv_Mod,

[0035] - determining (block 4, Figure 6 and block 24, Figure 8) a second derated target temperature value TEVP Air out Der chrg Tgt of the cabin air flow rate leaving the cabin evaporator EVAP under vehicle charging conditions (Charging_Active = 1) as a function of the nominal target temperature value TEvp Air Out HVAC Tgt of the cabin air flow rate mAiR CAB EVAP leaving the cabin evaporator EVAP, of an external ambient temperature TAmt, and of a charging power PBatt chrg Avi available for the battery BATT of the vehicle,

[0036] - adopting (block 6, Figure 6, block 18, Figure 7, block 26, Figure 8) the first derated target temperature value TEvp-Air_out_Der_Drv_Tgt if the vehicle is under conditions other than charging (Charging_Active = 0) and if there are no requests for conditioning the cabin of the vehicle (Special_Cabin_Conditioning_Active = 0) incompatible with adopting the first derated target temperature valueEvpAir out Der Drv Tgt, and operating said thermal conditioning circuit CC as a function of the first derated target temperature value TEvp Air Out Der Drv Tgt,

[0037] - adopting (block 6, Figure 6, block 18, Figure 7, block 26, Figure 8) the second derated target temperature value TEvp Air Out Der chrg Tgt if the vehicle is under charging conditions (Charging_Active = 1) and if there are no requests for conditioning the cabin of the vehicle (Special_Cabin_Conditioning_Active = 0) incompatible with adopting the second derated target temperature value TEvp Air Out Der chrg Tgt, and operating the thermal conditioning circuit CC as a function of the second derated target temperature value TEvp Air Out Der chrg Tgt•

[0038] As envisaged by the method according to the invention, under vehicle charging condition an electric current is present which enters the vehicle from the outside, specifically from a charging station, while under conditions other than charging there is no electric current entering the vehicle from the outside.

[0039] In other words, the phrase "vehicle charging" denotes a condition wherein the vehicle absorbs current from the outside, specifically from a charging station, and said current is used for charging the high-voltage battery and / or for supplying one or more electric users of the vehicle, or else only for supplying the one or more electric users of the vehicle when the current is not input into the high-voltage battery. The event which discriminates the condition of "vehicle charging" from the condition "other than vehicle charging" is the input into the vehicle of an electric current coming from the outside, in particular coming from a charging station. This means that the fact that the vehicle is connected to a charging station does not necessarily imply a vehicle charging condition, specifically if there is no current transit taking place from the charging station to the vehicle (battery and / or electric users).

[0040] There will now be described all the aspects of the method according to the invention, with reference to the Figures 6 to 12.

[0041] Figure 6, diagram 10, shows a block diagram representative of a layering of the control logics acting on the circuit CC and managing the combined cooling of the battery and of the cabin of the vehicle by means of said circuit CC. In the circuit CC, the evaporator EVAP is only present in the circuit (or sub-circuit) portion which is in charge of cooling the cabin, i.e., the circuit CC distributes the thermal cooling power (which is output by the compressor EAC) between the sub-circuit in charge of the cabin cooling and the sub-circuit in charge of the battery cooling. For this reason, the control of the thermal conditioning of the cabin, which is schematically shown by a block 12 (HVAC control) comprises a combination of three controls, specifically:

[0042] - a first control 14 which, on the basis of the nominal target temperature value TEvp Air OutHVACigt of the cabin air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP, and on the basis of a target cooling power value to be output by the one or more battery evaporators EV_B1 and EV_B2, defines a target value of thermal cooling power which the compressor EAC must output, and which operatively corresponds to a target rotational speed neAc igt for the compressor EAC.

[0043] In other words, the compressor EAC shall attempt to meet both a cooling target of the cabin evaporator EVAP and a cooling target for the one or more battery evaporators EV_B1 and EV_B2 (i.e. for the one or more chillers). The rotational speed of the compressor is chosen in such a way as to output a cooling power which equals the sum of both power targets, in order to meet both cooling requests. Since the cabin evaporator EVAP and the one or more battery evaporators EV_B1 and EV_B2 (i.e. the one or more chillers) share the same temperature of the refrigerant fluid during the evaporation process, in order to meet both cooling requests one of them may be in overcooling conditions or in undercooling conditions (for example, the latter case occurs when, in order to avoid a freezing of the air moisture impinging upon the cabin evaporator EVAP, the overall cooling power is limited, with a consequent limitation of the rotational speed of the compressor EAC, thereby no longer meeting the initial request by the one or more chillers).

[0044] - a second control 16 which, on the basis of the derated target temperature value TEvp Air Out Der Tgt of the cabin air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP - which may be equal to TEvp Air Out Der Drv Tgt, Or tO TEVP_Air_Out_Der_Drv_Tgt, Or else tO TEvp-Air_out_HVAC_Tgtr if there are requests for conditioning the cabin of the vehicle (Special_Cabin_Conditioning_Active = 1) incompatible with adopting the values TEvp Air OutDerDrvTgt or TEvp Airout Dei igt, defines a distribution of thermal power between the sections of the circuit CC which are in charge of cooling the cabin and of cooling the battery BATT. Operatively, the control 16 defines a target value of coolant flow rate to be sent to the one or more chillers mchiiier Tgt, and a number of chillers to be kept active simultaneously, represented by a command ShtoffVlv_Act which, when it is imparted, corresponds to a command to switch to the closed position for one or more of the valves SV_CHL1, SV_CHL2, and generally for one or more of the shut-off valves arranged upstream of the inlet of each chiller;

[0045] - a third control 18 upstream of the control 16, and configured to determine the derated target value Air out Der Tgt which corresponds to adopting the first or the second derated target value TEvp Air Out Der Drv Tgt or ~ as described in the foregoing - if the electric power available for cooling the cabin of the vehicle and the battery BATT (which is drawn from the same battery BATT) is completely exploited. In this regard, arranging the control 18 upstream of the control 16 implies adapting the coolant flow rate value mChiiierTgt and possibly imparting the command ShtoffVlv_Act to the derated target TEvp-Air-Out_Der_Tgt.

[0046] Figures 8 and 9, diagrams 20 and 30, schematically and generally show the method according to the invention. Referring to Figure 8, diagram 20, the block 22 is representative of the determination of the first derated target value TEvp Air Out Der Drv Tgt, i.e. a temperature value of the air flow rate mAiRleaving the cabin evaporator EVAP, which is derated due to the complete exploitation of the cooling power under conditions other than vehicle charging. As can be seen in the diagram of Figure 8, the determination is carried out as a function of a current driving mode Drv_Mode (in the preferred embodiment, whereas in other embodiments and / or in embodiments implemented on vehicle which do not offer any option of selecting the driving mode, the determination does not take the current driving mode into account), as a function of the nominal target temperature value TEvp Air OutHVACigt determined by the control 12, and as a function of the temperature TAmb of the external environment. The block 24, on the other hand, is representative of the determination of the second derated target value TEvpAir OutDerchrgigt, i.e. a temperature value of the air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP which is derated due to the complete exploitation of the cooling power under vehicle charging conditions. As can be seen in the diagram of Figure 4, the determination is operated as a function of a charging power PBattchrgAvi available for the battery BATT (dependent on the characteristics of the charging station), of the nominal target temperature value TEVPAiroutHVACTgt determined by the control 12, and of the temperature TAmb of the external environment.

[0047] The outputs of the blocks 22, 24, i.e. the derated target values TEvp-Air_out_Der_Drv_Tgtz TEvp-Air_out_Der_chrg_Tgtz are input into the block 26, which defines the (derated or non-derated) target value to be adopted for the temperature of the air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP as a function of the nominal target value TEvp Air OutHVACTgt, as a function of the presence of one or more requests for conditioning the cabin of the vehicle (Special_Cabin_Conditioning_Active) which are incompatible with adopting the first or the second derated target temperature value, and as a function of the vehicle being under charging conditions (Charging_Active) . The first circumstance, i.e. the presence of one or more requests for conditioning the cabin of the vehicle which are incompatible with adopting the first or the second derated target temperature value Tsvp_Air_Out_Der_Drv_Tgtr TEvp_Air_out_Der_chrg_Tgt, is represented by a variable Special_Cabin_Conditioning_Active, which acquires the logic state "0" (FALSE) when there are no requests incompatible with adopting the first or the second derated target temperature value TEVP—Air_Out—Der_Drv_Tgtr TEvp_Air_Out_Der_Chrg_Tgtr and the logiC State "1" (TRUE) when there are requests incompatible with adopting the first or the second derated target temperature value TEvp_Air_Out_Der_Drv_Tgt, TEVP—Air_Out—Der_Chrg_Tgt. An example of such a request comprises a request for defogging / defresting (so-called defrost mode) the windshield of the vehicle by means of the conditioning system comprising the evaporator EVAP (which is anyway essential for a rapid defogging): indeed, it is a request which has a direct impact on the travel safety of the vehicle, since a clouded or frozen windshield impairs visibility .

[0048] Since meeting such a request would practically lead to a derating of the performances of the evaporator EVAP, due to the increase of the target temperature value of the air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP, the method according to the invention - block 26 - envisages maintaining the nominal target temperature value TEVP Air out HVAC Tgt of the heat transfer liquid entering the first heat exchange device / cabin heater CAB, if there is a request for conditioning the cabin of the vehicle (Special_Cabin_Conditioning_Active = 1) incompatible with adopting the first or the second derated target temperature value TEvpAir out Der Drv Tgt, Tsvp_Air_Out—Der_Chrg_Tgt•

[0049] The second circumstance, i.e. the fact that the vehicle is under charging conditions, is represented by a further variable Charging_Active, which acquires the logic state "0" (FALSE) when the vehicle is not under charging conditions, and the logic state "1" (TRUE) when the vehicle is under charging conditions. Unlike the variable Special_Cabin_Conditioning_Active, the logic state whereof determines - or does not determine - a precedence of the nominal target value TEvp Air Out HVAC Tgt over the target values TEvp-Air-Out_Der_Drv_Tgt,

[0050] TEVP—Air_out—Der_chrg_Tgt / the logic state of the variable Charging_Active essentially determines the selection of one out of the first derated target value TEVP Air out Der Drv Tgt and the second derated target value TEVP_Air_Out—Der_Chrg_Igt•

[0051] Referring to Figure 9, diagram 30, it shows the interaction of the variables

[0052] Special_Cabin_Conditioning_Active and Charging_Active with the determinations as per the method according to the invention.

[0053] In detail, a first switch 32 is configured to output a raw derated target value TEvp-Air-Out_Der_Raw_Tgt of the temperature of the air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP, which may correspond to the first derated target value TEvp Air OutDerDrvTgt or to the second derated target value TEvp Air Out Der chrg Tgt as a function of the logic state of the variable Charging_Active, which acts as a control variable for the switch 32. A block 34 defines a logic condition which determines the output TEVPAir out Der Raw Tgt of the switch 32, in particular based on the fact that the logic state of the variable Charging_Active corresponds to "1" (TRUE). In the affirmative case, i.e. Charging_Active = 1, the output of the switch 32 corresponds to the condition shown in Figure 9, l.e. TEvp-Air_out_Der_Raw_Tgt=TEVP_Air_Out—Der_Chrg_Tgtr the second derated target value which corresponds to a vehicle under charging conditions (which is consistent with the meaning of the variable Charging_Active).

[0054] In the negative case, i.e. Charging_Active = 0 (FALSE), the output of the switch 32 corresponds to the opposite condition with respect to the condition shown m Figure 9, thus TEvp-Air_out_Der_Raw_Tgt=Tsvp_Air_Out_Der_Drv_Tgtr the first derated target value which corresponds to a vehicle under conditions other than charging.

[0055] The output TEvp-Air_out_Der_Raw_Tgt of the switch 32 is input into a second switch 36, which is configured to output an unlimited derated value TEvp Air Out Der uniim Tgt of the temperature of the air flow rate mAERCAB EVAP leaving the cabin evaporator EVAP, which may correspond to the raw derated target value TEvp Air Out Der Raw Tgt output by the switch 32, or to the nominal target temperature value TEVPAirout HVAC Tgt as a function of the logic state of the variable Special_Cabin_Conditioning_Active, which operates as a control variable for the switch 36. A block 38 defines a logic condition which determines the output TEvp_Air_out_Der_unLim_Tgt of the switch 36, in particular the fact that the logic state of the variable Special_Cabin_Conditioning_Active corresponds to "0" (V TRUE, thus FALSE) . In the affirmative case, i.e. Special_Cabin_Conditioning_Active = 0 (V TRUE), the output of the switch 36 corresponds to the condition shown in Figure 9, i.e. TEvp-Air-Out_Der_unLim_Tgt TEVPAir out Der Raw Tgt, thus to the first derated target value corresponding to what has been determined by the switch 32. In the negative case, i.e.

[0056] Special_Cabin_Conditioning_Active = 1 (= TRUE), the output of the switch 36 corresponds to the nominal target value determined by the control 12, i.e. Tsvp_Air_Out_Der_UnLim_Tgt=TEvp-Air_out_HVAC_Tgt• AS described in the foregoing, this derives from the meaning of the variable Special_Cabin_Conditioning_Active : if there are requests for thermal conditioning which are incompatible, basically since they have a priority over derating, with adopting the first or the second derated value, the method according to the invention keeps the nominal target value TEvp-Air_out_HVAc_Tgt•

[0057] Finally, a final derated target value TEvp Air OutDerigt is defined as the greater (block 39, MAX) of the unlimited derated target value TEvp Air OutDerunLim Tgt and a minimum temperature value TEvp Air OutMin of the cabin air flow rate mAIR CAB EVAP leaving the cabin evaporator EVAP. In other words, at the block 39 the final derated target value has a lower limit at the value TEvp Air OutMin• The following Figure 10, diagram 40, shows the determination of the value TEvp Air OutMin, which in the preferred embodiment described herein is determined by a map M40 which provides the value TEvp Air OutMin as a function of a maximum cell temperature TBatceilMax of the battery (BATT). To this end, the temperature of the single battery cell is used, instead of the average temperature of the battery BATT, to avoid the risk of damaging or destroying the same battery (with the consequent risk of fire): in other words, by determining the value TEVP Air out Min on the maximum admissible temperature TBat ceii Max for the single cell, it is more likely to mitigate the temperature (and the risk) of the cell which is actually the most critical in the set of cells of the battery BATT. The value TEvp Air OutMin must be understood as an upper performance limit of the evaporator EVAP, i.e. as an upper performance limit of the circuit CC, considering the distribution of the thermal cooling power between the cabin and the battery BATT: if the temperature of the battery cells is low, it is possible to have a low value of minimum temperature TEvp Air Out Min, thus a high cooling performance by the evaporator EVAP, whereas, as the temperature of the battery cell increases, specifically as the temperature of the battery cell increases (considering a qualitative evolution) beyond a knee K40, the temperature TEVP Air out Min rises, testifying the shift of the cooling power towards the one or more chillers CHL1, CHL2, thus towards the battery BATT.

[0058] The following Figures 11 and 12 show the determination of the derated target values TEVP_Air_Out—Der_Drv_Tgtr TEvp_Air_out_Der_chrg_igt in the preferred embodiment of the invention.

[0059] Referring to figure 11, diagram 50, determining the first derated target temperature value TEvp Air Out Der Drv Tgt of the cabin air flow rate mATRCAB EVAP leaving the cabin evaporator EVAP under conditions other than vehicle charging includes determining the first derated target temperature value TEvp Air OutDerDrvTgt as the greater (block 52, MAX) of the nominal target temperature value TEVP-Air_out_HVAC_Tgt of the cabin air flow rate mAER_CAB_EVAP leaving the cabin evaporator EVAP and the lower (block 54, MIN) of: i) an increased temperature value

[0060] TEVP_Air_Out—Der_DrvMod—Tgt Of the Cabin air flOW rate mAER-CAB-EVAP leaving the cabin evaporator EVAP as a result of the condition other than vehicle charging, and dependent on the temperature TAmt of the external environment and on the current driving mode Drv_Mod, ii) a sum (block 56) of the nominal target temperature value TEvp Air OutHVACTgt of the cabin air flow rate mATRCAB EVAP leaving the cabin evaporator EVAP and a temperature rise value ATEvp Air Out Der DrvMod Tgt of the cabin air flow rate mATRCAB EVAP leaving the cabin evaporator EVAP under conditions other than vehicle charging, dependent on the temperature TAmt of the external environment and on the current driving mode Drv_Mod.

[0061] The temperature rise value TEvp-Air-0ut_Der_DrvMod_Tgt is determined by means of a map M57, which provides said value as a function of the temperature TAmband of the current driving mode Drv_Mode: the map M57 in Figure 11 shows, by way of example, four temperature curves TEvp_Air_0ut_Der_DrvMod_igt as a function of the temperature TAmb and parameterized with respect to corresponding driving modes Drv_Mod_l, Drv_Mod_2, Drv_Mod_3, Drv_Mod_4, mentioned in order of decreasing aggressivity (for example, with reference to a preferred embodiment, Drv_Mod_l = Race, Drv_Mode_2 = Sport, Drv_Mod_3 = GT, Drv_Mod_4 = Max Range). From a qualitative point of view, the temperature TEvp Air Out Der DrvMod Tgt increases as the aggressivity of the driving mode increases (for example, in the Race mode, it is important to rapidly cool the battery BATT, and therefore the transfer of thermal cooling power towards the one or more chillers CHL1, CHL2 is promoted), and it decreases as the external ambient temperature increases, since when said temperature TAmt is higher, the availability of thermal cooling power in favour of the cabin is generally greater.

[0062] The temperature rise value ATEvp-Air_out_Der_DrvMod_Tgt of the cabin air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP is determined by means of a map M58, which provides said value as a function of the temperature TAmt and of the current driving mode Drv_Mode: the map M58 in Figure 11 shows, by way of example, four temperature curves ATEvp A±r out Der DrvMod Tgt as a function of the temperature TAmb and parameterized with respect to the corresponding driving modes Drv_Mod_l, Drv_Mod_2, Drv_Mod_3, Drv_Mod_4, mentioned in order of decreasing aggressivity (for example, as mentioned for the preferred embodiment, Drv_Mod_l = Race, Drv_Mode_2 = Sport, Drv_Mod_3 = GT, Drv_Mod_4 = Max Range). From a qualitative point of view, the temperature rise value ATEvp_Air_0ut_Der_DrvMod_Tgt increases as the aggressivity of the driving mode increases (for example, in the Race mode it is important to rapidly cool the battery BATT, and therefore the transfer of thermal cooling power to the one or more chillers CHL1, CHL2 is promoted), and it decreases as the external ambient temperature increases, since with a higher temperature TAmt the availability of cooling power in favour of the cabin of the vehicle is generally greater.

[0063] Referring to Figure 12, diagram 60, determining the second derated target temperature value TEvp_Air_Out_Der_Chrg_Igt Of the Cabin air flOW rate lilAIR-CAB-EVAP leaving the cabin evaporator EVAP under vehicle charging conditions includes determining the second derated target temperature value TEvp A±r out Der chrg Tgt as the greater (block 62, MAX) of the nominal target temperature value TEvp A±r out HVAC Tgt of the cabin air flow rate IAIR CAB EVAP leaving the cabin evaporator EVAP and the lower (block 64, MIN) of: iii) a temperature value TEvp-Air_out_Der_PBatt_Tgt of the cabin air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP increased as a result of the charging condition on the vehicle, and dependent on the external ambient temperature TAmb and on a charging power PBatt chrg Avi available for the battery BATT of the vehicle, iv) a sum (block 66) of the nominal target temperature value TEvp A±r out HVAC Tgt of the cabin air flow rate mAiR CAB EVAP leaving the cabin evaporator EVAP and a temperature rise value ATEvp A±r out Der chrg Tgt of the cabin air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP under conditions other than vehicle charging, and dependent on the external ambient temperature TAmb and on the charging power PBatt chrg Avi available for the battery BATT of the vehicle.

[0064] The temperature rise value TEvp-Air_out_Der_chrg_Tgt is determined by means of a map M67 which provides said value as a function of the temperature TAmb and of the charging power PBattchrgAvi available for the battery BATT of the vehicle: the map M67 in Figure 12 shows, by way of example, four temperature curves TEvp Air Out Der chrg Tgt as a function of the temperature TAmt and parameterized with respect to corresponding levels of charging power PBatt chrg Avi available for the battery BATT of the vehicle PBatt_Chrg_Avl_l, PBatt_Chrg_Avl_2 , PBatt_Chrg_Avl_3, PBatt_Chrg_Avl_4, mentioned in order of increasing power availability (thus PBatt_Chrg_Avl_l > PBatt_Chrg_Avl_2

[0065] > PBatt_Chrg_Avl_3 > PBatt_Chrg_Avl_4).

[0066] From a qualitative point of view, the temperature TEVP Air out Der chrg Tgt increases as the available charging power increases (for example, with a charging with high power availability it is important to rapidly cool the battery BATT, in order to avoid a derating of the charging performances), and decreases as the external ambient temperature TAmt increases, since with a higher temperature TAmb the availability of thermal cooling power in favour of the cabin increases.

[0067] The temperature rise power ATEvp-Air_out_Der_chrg_Tgt of the cabin air flow rate mAiRCAB EVAP leaving the cabin evaporator EVAP is determined by means of a map M68, which provides said value as a function of the temperature TAmb and of the charging power PBattchrgAvi available for the battery BATT of the vehicle: the map M68 in Figure 12 shows, by way of example, four temperature curves TEvp A±routDerchrgTgt as a function of the temperature TAmb and parameterized with respect to corresponding levels of charging power PBattchrgAvi available for the battery BATT of the vehicle PBatt_Chrg_Avl_l, PBatt_Chrg_Avl_2 , PBatt_Chrg_Avl_3, PBatt_Chrg_Avl_4, mentioned in order of increasing power availability (thus PBatt_Chrg_Avl_l > PBatt_Chrg_Avl_2

[0068] > PBatt_Chrg_Avl_3 > PBatt_Chrg_Avl_4).

[0069] From a qualitative point of view, the temperature rise value ATEvp A±r out Der chrg Tgt of the cabin air flow rate W iRCAB EVAP leaving the cabin evaporator EVAP increases as the available charging power increases (for example, under charging with high power availability, it is important to rapidly cool the battery BATT, in order to avoid a derating of the charging performances), and decreases as the external ambient temperature TAmb increases, since with a higher temperature TAmb it is not advisable to deviate significantly from the target determined by the control 12.

[0070] Operatively, once the final derated target value TEVP Air out Der Tgt is known, as determined according to what has been described in the foregoing, the method according to the invention uses the target value under consideration to control the cooling circuit CO - as anticipated in the foregoing. Specifically, the final derated target value TEvp A±r out Der Tgt is used for recalculating the refrigerant fluid flow rate mRFRCAB EVAP to be supplied to the cabin evaporator EVAP, and for a consequent recalculation of a thermal cooling power ECAB CLG which the evaporator is to output, as well as for the - again, consequent - calculation of the refrigerant fluid flow rate to be sent to the one or more chillers W ER-CHL•

[0071] As it is commonly known, the thermal cooling powers ECAB CLG and ECHL CLG which can be output by the cabin evaporator EVAP and by the set of the battery evaporators EV_B1 and EV_B2 of the chillers CHL1, CHL2 depend on the refrigerant fluid flow rate traversing them (mRFRCAB EVAP and IIIRFR CHL), as well as on the enthalpy jump between the inlet and the outlet. Expressed in formulae: is the thermal power exchanged by the cabin evaporator EVAP with the cabin air flow rate is the thermal power exchanged by the one or more active battery evaporators EV_B1, EV_B2 with the coolant traversing the chillers CHL1, CHL2, is the refrigerant fluid mass flow rate traversing the evaporator EVAP mRFRis the refrigerant fluid mass flow rate traversing the one or more active battery evaporators EV_B1, EV_B2 hCAB_EVAP_0UT and hCAB_EVAP_iN are the (specific) enthalpy values of the refrigerant fluid, at the outlet and at the inlet of the evaporator EVAP, respectively hCHL and hCHL are the (specific) enthalpy values of the refrigerant fluid, at the outlet and at the inlet of the one or more active battery evaporators EV_B1, EV_B2, respectively.

[0072] For the power which is subjected to derating in the method according to the invention, it is thus possible to write wherein is the cabin air mass flow rate which impinges upon the evaporator EVAP in the transit from the inlet section EVAP_IN to the outlet section EVAP_OUT (which is assumed as unvaried even after derating the target temperature thereof) the specific heat at constant pressure is the air temperature at the inlet section EVAP_IN of the evaporator EVAP, which can be generally measured by means of a temperature sensor upstream the evaporator, and which is equal to the ambient temperature TAmt in the absence of cabin air recirculation is the air temperature at the outlet section EVAP_OUT of the evaporator EVAP, which in this to TEvp-Air_out_Der_Tgt, is the temperature of the refrigerant fluid traversing the evaporator EVAP whereas similarly, for the power it is possible wherein : cpis the specific heat at constant pressure of the coolant is the temperature of the coolant at the inlet the one or more simultaneously active chillers is the temperature of the coolant at the outlet of the one or more simultaneously active chillers itcLN = itchiiier Tgt is the target coolant mass flow rate destined to the one or more chillers CHL1, CHL2, defined by the control 16 as a function of the derated target temperature TEvp-Air_out_Der_Tgt cpis the specific heat at constant pressure of the coolant is the air temperature at the inlet section P_IN of the evaporator EVAP, which can be generally measured by means of a temperature sensor upstream of the evaporator, and which is equal to the ambient temperature TAmb in the absence of air recirculation in the cabin.

[0073] The correlation RTH_CAB_EVAP - I1AIR_CAB_EVAP between the thermal resistance RTHCAB EVAP of the evaporator EVAP and the cabin air flow rate mAiRCAB EVAP is known, in the same way as the correlation RTHCHL TOT - ICLN CHL is known (wherein, as a consequence of the derating - control 16 - mCLN CHL = itchiiier Tgt) between the (overall) thermal resistance RTH CHL TOT of the one or more simultaneously active chillers and the coolant flow rate mCLN CHL through the one or more simultaneously active chillers. As an example, reference is made to the description of the Italian Industrial Invention Patent Application n. 102023000024474 in the name of the same Applicant.

[0074] As regards the refrigerant fluid, when it is in the vapour phase the correlation between the temperature TRFR_CAB_EVAP and the pressure PRFR_CAB_EVAP is known as well. Moreover, when the one or more chillers CHL and the evaporator EVAP are activated simultaneously - which corresponds to the case of interest for the method according to the invention - the temperature and the pressure of the refrigerant fluid at the outlet of both components are substantially the same. In this case, the chiller CHL is considered as a reference to calculate TRFR_CAB_EVAP and PRFR_CAB_EVAP (thUS TRFR_CAB_EVAP=TRFR_CHL and PRFR CAB EVAP = PRFR CHL)I since the temperature data relating to the coolant flow rate through the one or more chillers CHL are more accurate than the data relating to the cabin air flow rate.

[0075] Therefore, since the values of RTH CAB EVAP and TRFR CAB EVAP are known, it is possible to recalculate the new post-derating refrigerant fluid flow rate of the target temperature of the air flow rate mAiRCAB EVAP leaving the evaporator EVAP as:

[0076] (assuming that the target thermal cooling power ECAB CLG output for the cabin is in turn derated as a consequence of derating the target temperature of the air leaving the evaporator).

[0077] The new value of the refrigerant fluid flow rate IRFR CAB EVAP being known, it is possible to determine (control 16) the flow rate IURER CHL as a difference between a maximum available flow rate mRFRTOT,MAX of refrigerant fluid in the refrigeration cycle cooling circuit CC and the refrigerant fluid flow rate mRFRCAB EVAP. Therefore, mRFRCHL becomes an upper limit value for the refrigerant fluid flow rate sent to the one or more chillers, and for this reason it will now be referred to as mRFRCHL LIM- Therefore, as described in the further Italian Industrial Invention Patent Application n. 102023000026508 in the name of the same Applicant, it is possible to determine a target overall thermal resistance value RTH CHL TOT,LIM of the plurality of refrigeration devices CHL1, CHL2 in such a way as to limit the refrigerant fluid flow rate transiting in the battery evaporators EV_B1, EV_B2 of the plurality of refrigeration devices CHL1, CHL2 to the flow rate mRFRCHL as a function of the correlation between RTHCHL TOT and ftlChiller_Tgt•

[0078] Indeed, it is possible to write the cooling power output by the one or more chillers as wherefrom, by replacing mRFRCHL with the (limit) flow rate value mRFRCHL LIM determined by subtracting the flow rate rhRFR CAB EVAP (as a function of the derated value TEvp_Air_out_Der_Tgt) from the flow rate mRFR-T0T,MAx, it is possible to calculate the (limit) target value of overall thermal resistance RTH CHL TOT,LIM as:

[0079] RTH_CHL_TOT,LIM (TCLN_CHL_IN TRFR_CHL) / [iiRFR_CHL-LIM* (hRFR_CHL—OUT hRFR_CHL_IN)J wherein:

[0080] TCLN CHL IN is a temperature of the coolant at the inlet of the one or more refrigeration devices

[0081] TRFRCHL is a temperature of the refrigerant fluid flowing through the one or more battery evaporators, mRFRCHL,LIM is the limit refrigerant fluid flow rate to be sent to the one or more battery evaporators of the one or more chillers hRFRCHL IN is an enthalpy of the refrigerant fluid entering the battery evaporators hRFRCHL OUT is an enthalpy of the refrigerant fluid leaving the battery evaporators.

[0082] Once the new limit value of the target overall thermal resistance RTH CHL TOT,LIM is known, it is possible to determine a number of refrigeration devices CHL1, CHL2 to be kept simultaneously active to output the limit value of the target overall thermal resistance RTH CHL TOT,LIM and the related coolant flow rate mchiiierTgt (control 16) thanks to the correlation between the thermal resistance of the chillers and the coolant flow rate traversing them. This may involve, as a function of the target overall thermal resistance RTH CHL TOT,LIM, simultaneously activating both chillers CHL1, CHL2 or only one of them, therefore - with reference to the control 16 - determining imparting the command ShtoffVlv_Act to exclude the corresponding chiller.

[0083] The diagram in Figure 1, moreover, evidently shows that the cabin evaporator EVAP and the set of chillers CHL1, CHL2 are hydraulically arranged in parallel with one another, so that the increase of hydraulic resistance upstream of the evaporator EVAP increases the refrigerant fluid flow rate which is sent to the chillers, and vice versa. This means that the control of the flow rates mRFRCAB EVAP and mRFRCHL may be operated by means of the expansion / throttling valves TXV_EVAP, TXV_CHL1, TXV_CHL2. By varying the passage section in the traversing area of said valves, it is possible to vary the hydraulic resistance thereof, and thus to vary the hydraulic resistance upstream of the evaporators (EVAP and evaporators internal to CHL1, CHL2) and the refrigerant fluid flow rates. On the other hand, according to what has been described in the foregoing, by means of the shut-off valves SV_CHL1 and SV_CHL2 it is possible to select the number of simultaneously active chillers simply by excluding one or more chillers, specifically excluding the respective battery evaporators, by completely closing the corresponding shut-off valve.

[0084] The enthalpy values at the inlet and at the outlet of the one or more simultaneously active battery evaporators EV_B1, EV_B2 - and the same is true for the evaporator EVAP - may be derived from the enthalpy diagram of the refrigerant fluid if, for example, the pressure and temperature conditions of the refrigerant fluid at the respective inlet and outlet are known. The knowledge of the conditions may derive from a direct reading (for example, in the circuit CC there are preferably provided a temperature sensor and a pressure sensor of the refrigerant fluid leaving the condenser CNDS, which enable calculating the enthalpy of the refrigerant fluid leaving the condenser CNDS, which enthalpy corresponds to the enthalpy of the refrigerant fluid entering the evaporator EVAP and the one or more simultaneously active battery evaporators EV_B1, EV_B2; if a direct reading is not possible, the values may be derived e.g. according to the teachings of the Italian Industrial Invention Patent Application n. 102023000024474 in the name of the same Applicant - see the calculation of TRFR_CAB_EVAP / PRFR_CAB_EVAPr TRFR_CHL and PRFR CHL discussed in the foregoing.

[0085] If the (limit) target overall thermal resistance value is greater than or equal to a threshold value RTH CHL TOT,THR, then a single chiller is kept active, since this corresponds to a more resistive configuration from the thermal point of view. On the contrary, if the (limit) target overall thermal resistance value RTH CHL TOT,LIM is lower than said threshold value RTH CHL TOT,THRZ then both chillers CHL1, CHL2 are activated, since this corresponds to a less resistive configuration from the thermal point of view. In the presence of more than two chillers, it is possible to envisage progressive thresholds for activating a progressively increasing number of chillers.

[0086] If the circuit CO comprises a single chiller, then the only possible manner to vary the thermal resistance of the chillers so as to remain within the limit value is to vary the flow rate mchiiierTgt, since imparting the command ShtoffVlv_Act is not possible (imparting such a command would exclude the only chiller, and therefore would exclude the cooling of the battery BATT).

[0087] Thanks to the method according to the invention it is therefore possible to manage the derating of the thermal cooling power output in favour of the vehicle cabin in the case of a complete exploitation of the available thermal cooling power by maintaining a single refrigeration cycle cooling circuit both for the cabin and for the battery. This is possible by defining the derated target values TEvp-Air-Out_Der_Drv_Tgt, TEVP Air out Der chrg Tgt, and by recalculating the flow rate FR CAB EVAP “ and therefore, ultimately, the flow rate itchiiier Tgt - as a function of the one or of the other derated value, selected as a function of the conditions (charging or other than charging) of the vehicle, while always ensuring the best possible conditions in terms of comfort in the cabin and of meeting the needs of the thermal conditioning - especially the cooling - of the battery in the conditions of complete exploitation of the thermal (and electric) cooling power available to such ends.

[0088] In conditions of complete exploitation of the thermal power available for the combined cooling of the cabin and of the battery, the method according to the invention aims at finding a compromise between the cooling needs of the battery and the cooling needs of the cabin, by mitigating the redistribution of the thermal cooling power in favour of the high-voltage battery (which is a component which absorbs much more thermal cooling power in comparison with the cabin, due to the different nature of the heat transfer liquid used for the heat exchange with the circuit CC - air for the cabin, coolant for the battery) in such a way as to avoid excessively affecting the cooling of the cabin. In this regard, the derated target temperature value TEvp_Air_Out_Der_Drv_Tgt OU TEvp_Air_Out_Der_Chrg_Tgt mUSt be Understood both as a reduction of the performance request of the cabin evaporator EVAP and as the upper temperature limit for the cooling needs of the cabin, in such a way as to avoid situations - which are common in known solutions - wherein the thermal cooling power is completely directed to the battery. Of course, the implementation details and the embodiments may amply vary with respect to what has been described and illustrated herein without departing from the extent of the present invention, as defined by the annexed claims.

Claims

CLAIMS1. A method for the operation of a refrigeration cycle thermal conditioning circuit (CC) of a vehicle, in particular a vehicle with an electric powertrain, the thermal conditioning circuit (CC) including:- a compressor (EAC) having an intake port and a delivery port, a condenser (CNDS) having an inlet in fluid communication inlet with said intake port of the compressor (EAC),- at least one evaporation device (EVAP, EV_B1, EV_B2) having an inlet in fluid communication with an outlet of said condenser (CNDS) and an outlet in fluid communication with the intake port of the compressor, said at least one evaporation device (EVAP, EV_B1, EV_B2) being in a heat exchange relationship with a respective heat transfer fluid other than a refrigerant circulating through said refrigeration cycle thermal conditioning circuit (CC), a shut-off valve (SV_EVAP, SV_CHL1, SV_CHL2) arranged upstream of the inlet of said at least one evaporation device (EVAP, EV_B1, EV_B2), preferably of each evaporation device (EVAP, EV_B1, EV_B2), each shutoff valve having a first open operating condition and a second closed operating condition, wherein said at least one evaporation device (EVAP, EV_B1, EV_B2) includes a cabin evaporator (EVAP) for the thermal conditioning of a vehicle cabin, wherein said heat transfer fluid includes a flow of cabin air supplied to the cabin, and wherein said at least one evaporation device further includes one or more battery evaporators (EV_B1, EV_B2) of corresponding one or more chillers (CHL1, CHL2) for the thermal conditioning of a battery (BATT) of the electric powertrain of the vehicle, and wherein said heat transfer fluid includes a coolant ofsaid battery (BATT) flowing through a circuit in a heat exchange relationship with a corresponding battery evaporator (EV_B1, EV_B2) the method including: determining (2, 22) a first derated target temperature value) of the cabin air flow rate leaving said cabin evaporator (EVAP) under conditions other than vehicle charging (Charging_Active = 0) as a function of a nominal target temperature valueof the cabin air flow rate leaving said cabin evaporator (EVAP), an external ambient temperature (TAmb), and preferably in accordance with a current driving mode (Drv_Mod), determining (4, 24) a second derated target temperature value (TEvp A±r out Der chrg Tgt) of the cabin air flow rate leaving said cabin evaporator (EVAP) under vehicle charging conditions (Charging_Active = 1) as a function of the nominal target temperature value of the cabin air flow rate leaving said(EVAP), an external ambient temperature (TAmb), and an available charging power for said battery (BATT) of the vehicle,- adopting (6, 18, 26) the first derated temperature target value (TEvp-Air_out_Der_Drv_Tgt) if the vehicle is in conditions other than other than vehicle charging (Charging_Active = 0) and if there are no requests for conditioning of the vehicle cabin(Special_Cabin_Conditioning_Active = 0) incompatible with adopting the first derated target temperature valueAir_out—Der_Drv_Tgt) and operating said thermal conditioning (CC) circuit as a function of said first derated target temperature value (TEvp A±r out Der Drv Tgt),- adopting (6, 18, 26) the second derated target temperature value (TEvp A±r out Der chrg Tgt) if the vehicle is in charging condition (Charging_Active = 1) and if thereare no requirements for conditioning the vehicle cabin compartment (Special_Cabin_Conditioning_Active = 0) incompatible with adopting the second derated target temperature value (TEvp-Air-Out_Der_chrg_Tgt), and operating said thermal conditioning circuit (CC) as a function of said second derated target temperature value (TEvp_Air_Out_Der_Chrg_Tgt)•2. The method of claim 1, further including maintaining the nominal target temperature value(TEvpAir out HVAC Tgt) of the cabin air flow rate leaving said cabin evaporator (EVAP) if there is a demand for conditioning of the vehicle cabin(Special_Cabin_Conditioning_Active = 1) that is incompatible with adopting the first (TEvp Air Out Der Drv Tgt) or second (TEvp Air OutDerchrgTgt) derated target temperature values.

3. The method of claim 1 or claim 2, wherein said adopting (6, 18, 26) the first derated target temperature value (TEvp-Air_out_Der_Drv_Tgt) or adopting (6, 18, 26) the second derated target temperature value (TEVP—Air_Out—Der_Chrg_Tgt) ComprisesI defining a raw derated target value (TEvp_Air_out_Der_Raw_Tgt) of the temperature of the cabin air flow rate leaving the cabin evaporator (EVAP) corresponding to the first derated target temperature value (TEvp Air OutDerDrv Tgt) if the vehicle is in conditions other than vehicle charging (Charging_Active = 0), or to the second derated target temperature value (TEvp_Air_out-Der_chrg_Tgt) if the vehicle is in charging condition (Charging_Active = 1), defining an unlimited derated target value (Tsvp—Air_out—Der_unLim_Tgt) corresponding to the raw derated target value (TEvp-Air-Out_Der_Raw_Tgt) of the temperature of the cabin air flow rate leaving the cabin evaporator (EVAP) if there is no demand for air conditioning of thevehicle cabin (Special_Cabin_Conditioning_Active = 0) that is incompatible with adopting the first (TEVP—Air_Out—Der_Drv_Tgt) Or the SOCOnd (TEvp__Air_Out_Der_Chrg_Tgt) derated temperature target value, or corresponding to the nominal temperature target value (TEvp Air Out HVAC Tgt) of the cabin air flow rate leaving the cabin evaporator (EVAP) if there is a demand for vehicle cabin air conditioning (Special_Cabin_Conditioning_Active = 1) that is incompatible with adopting the first (TEvp_Air_Out-Der_Drv_Tgt) or the second (TEvp__Air_Out—Der_Chrg_Tgt) derated temperature target value,- defining a final derated target temperature value (TEvpAir out Der Tgt) as the greater of the unlimited derated target value (TEvp-Air-Out_Der_unLim_Tgt) and a minimum temperature value (TEvp Air Out Tgt) of the cabin air flow rate leaving the cabin evaporator (EVAP).

4. The method of claim 3, wherein said minimum temperature value (TEvp Air OutTgt) of the cabin air flow rate leaving the cabin evaporator (EVAP) is defined as a function of a maximum cell temperature (TBatceilMax) of said battery (BATT).

5. The method of any of the preceding claims, wherein said determining the first derated target temperature value (TEvp Air Out Der Drv Tgt) of the cabin air flow rate leaving said cabin evaporator (EVAP) under conditions other than vehicle charging includes determining the first derated target temperature value (TEvP—Air_out—Der_Drv_Tgt) as the greater (52) of the nominal target temperature value (TEvp Air Out HVAC Tgt) of the cabin air flow rate leaving said cabin evaporator (EVAP) and the lower (54) of:(i) an increased temperature value for the cabin air flow rate leaving that cabin evaporator (EVAP) (Tsvp—Air_out—Der_DrvMod—Tgt) as a result of the condition other than charging the vehicle and dependent on thetemperature of the external environment (TAmb) and the driving mode in force (Drv_Mod),(ii) a sum (56) of the nominal target temperature value (TEvp-Air_out_HVAc_Tgt) of the cabin air flow rate leaving said cabin evaporator (EVAP) and a temperature rise value (ATEvp-Air_out_Der_DrvMod_Tgt) of the cabin air flow rate leaving said cabin evaporator (EVAP) under conditions other than vehicle charging depending on the temperature of the external environment (TAmb) and the current driving mode (Drv_Mod).

6. The method of any of the preceding claims, wherein said determining the second derated target temperature value (TEvp Air Out Der chrg igt) of the cabin air flow rate leaving said cabin evaporator (EVAP) under vehicle charging conditions includes determining the second derated target temperature value (TEvp-Air_out_Der_chrg_igt) as the greater (62) of the nominal target temperature value (TEvp Air Out HVAC igt) of the cabin air flow rate leaving said cabin evaporator (EVAP) and the lower (64) of:(iii) a temperature value of the cabin air flow rate leaving said cabin evaporator (EVAP) increased (TEvp-Air_out_Der_PBatt_igt) as a result of the charging condition of the vehicle and dependent on an external ambient temperature (TAmb), and an available charging power for said vehicle battery (BATT),(iv) a sum (66) of the nominal target temperature value (TEvp_Air_out_HVAc_Tgt) of the cabin air flow rate leaving said cabin evaporator (EVAP) and a value of temperature rise (ATEvp A±routDerchrgTgt) of the cabin air flow rate leaving said cabin evaporator (EVAP) under conditions other than vehicle charging and dependent on an external ambient temperature (TAmb) and an available charging power for said battery (BATT) of the vehicle.

7. The method of any of claims 3 to 6, wherein saidoperating the thermal conditioning circuit (CC) as a function of said first derated target temperature value (TEvp Air out Der Drv Tgt) or second derated temperature target value (Tgvp_Air_Out—Der_Chrg_Tgt) Includes: determining a flow rate of refrigerant fluid (W FR CAB EVAP) to be sent to said cabin evaporator (EVAP) to output a target thermal cooling power (ECAB EVAP) dependent on said final derated target temperature value (TEvp_Air_Out—Der_Tgt)r- determining a limit flow rate of refrigerant fluid (W FR CHL LIM) to be sent to one or more battery evaporators (EV_B1, EV_B2) of corresponding one or more refrigeration devices (CHL1, CHL2) as the difference between a maximum available flow rate (mRFRTOT,MAX) of refrigerant fluid in the refrigeration cycle (CC) cooling circuit and said flow rate of refrigerant fluid to be sent to said cabin evaporator (EVAP),- determining a target overall thermal resistance value (RTH CHL TOT,LIM) of said one or more refrigeration devices (CHL1, CHL2) such as to limit the flow rate of refrigerant fluid flowing through the battery evaporators (EV_B1, EV_B2) of the corresponding one or more refrigeration devices (CHL1, CHL2) to said limit flow rate of refrigerant fluid (mRFRCHL LIM),- determining a target value (mChiiierTgt) of the flow rate of coolant entering the one or more refrigeration devices (CHL1, CHL2) as a function of said target overall thermal resistance value (RTH CHL TOT,LIM)•8. The method of claim 7, further including determining a number of refrigeration devices (CHL1, CHL2) to be kept active at the same time in order to output said target overall thermal resistance value (RTH_CHL_TOT,LIM)•9. The method of claim 7 or claim 8, wherein said target overall thermal resistance value (RTH CHL TOT,LIM) iscalculated as:RTH_CHL_TOT,LIM (TCLN CHL IN TRFR-CHL) / [I1RFR_CHL-LIM* (hRFR_CHL_OUT hRFR_CHL_IN)J wherein:RTH CHL TOT,LIM is said target overall thermal resistance valueTCLN CHL IN is a temperature of the coolant at the inlet of the one or more refrigeration devicesTRFR CHL is a temperature of the refrigerant fluid flowing through the one or more battery evaporators (EV_B1, EV_B2),IIRFR LIM is said limit flow rate of refrigerant fluid (W FR CHL LIM) to be sent to the one or more battery evaporators (EV_B1, EV_B2) hRFRCHL IN is an enthalpy of the refrigerant fluid entering the one or more battery evaporators (EV_B1, EV_B2), hRFRCHL OUT is an enthalpy of the refrigerant fluid leaving the one or more battery evaporators (EV_B1, EV_B2).

10. The method of claim 8 or claim 9, wherein if said target overall thermal resistance value (RTH CHL TOT,LIM) is greater than or equal to a threshold value (RTH CHL TOT,THR), said determining a number of refrigeration devices to be kept active at the same time (CHL1, CHL2) to output the target overall thermal resistance value (RTH CHL TOT,LIM) includes maintaining only one active refrigeration device.

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