FR3148806A1 - DETERMINATION OF THE PUMP RATE OF A COOLING CIRCUIT HAVING SEVERAL PARTS, FOR A VEHICLE - Google Patents

Abstract

A method is implemented in a vehicle comprising a powertrain comprising first and second drive machines having first and second measured temperatures, and a cooling circuit in which a heat transfer fluid circulates and comprising a first part comprising a pump and a valve having an inlet supplied with heat transfer fluid by the pump and first and second outlets, and second and third parts connected to the first and second outlets and capable of cooling the first and second drive machines. This method comprises a step (10-20) in which first and second speeds are determined, necessary for cooling the first and second drive machines, as a function of the first and second measured temperatures, then the pump is operated according to a speed which is the greatest of the first and second speeds determined. Figure 3

Description

DETERMINATION OF THE PUMP RATE OF A COOLING CIRCUIT HAVING SEVERAL PARTS, FOR A VEHICLE Technical field of the invention

The invention relates to vehicles comprising a powertrain comprising two drive machines, and more specifically to the control of the cooling of such drive machines.

State of the art

Some vehicles, possibly land-based (and for example of the automobile type), include a powertrain (or GMP) comprising first and second driving machines capable of providing engine torque to move them, and a cooling circuit capable of cooling these first and second driving machines with a heat transfer fluid.

It should be noted that the invention concerns all types of GMP, whether they are purely thermal, purely electric or hybrid (thermal and electric). Furthermore, when the GMP comprises at least one electric motor, the latter can produce its output torque from the electrical energy provided by an electrical energy source in the form of a main (or traction) battery or a fuel cell.

Sometimes the cooling circuit includes:

- a first part comprising a pump and a valve having an inlet supplied with heat transfer fluid by this pump and first and second outlets,

- a second part connected to the first outlet of the valve and suitable for cooling at least the first driving machine, and

- a third part connected to the second valve outlet and suitable for cooling the second driving machine.

The valve being a three-way type, it can take four states:

- a first closed state in which it prevents the supply of heat transfer fluid to the second and third parts of the cooling circuit,

- a second state in which it allows the supply of heat transfer fluid to the second part of the cooling circuit, and prevents the supply of heat transfer fluid to the third part of the cooling circuit,

- a third state in which it allows the supply of heat transfer fluid to the third part of the cooling circuit, and prevents the supply of heat transfer fluid to the second part of the cooling circuit, and

- a fourth state in which it allows the supply of heat transfer fluid to the second and third parts of the cooling circuit.

The placement of the valve in its first state is decided when the first and second temperatures measured respectively in the first and second driving machines are respectively lower than first and second thresholds.

The placement of the valve in its second state is decided when the first and second measured temperatures are respectively higher than the first threshold and lower than the second threshold.

The placement of the valve in its third state is decided when the first and second measured temperatures are respectively lower than the first threshold and higher than the second threshold.

The placement of the valve in its fourth state is decided when the first and second measured temperatures are respectively higher than the first and second thresholds.

In each of the second, third and fourth states, the cooling requirements may vary, as this depends in particular on the magnitude of each temperature threshold exceedance. Consequently, a vehicle computer, generally the one that supervises its powertrain, is responsible for controlling the pump speed according to the first and second temperatures measured respectively in the first and second drive engines.

More specifically, currently the aforementioned calculator determines the pump speed based on the largest of the temperature threshold exceedances. Generally, this determination is made by means of a search in a table establishing a correspondence between pump speeds and temperature threshold exceedances.

A major drawback of this control method is that the table contains speeds that are percentages of the maximum pump speed, which is equal to the maximum speed required to produce the maximum flow rate sometimes required by the most demanding part of the cooling circuit. It will therefore be understood that this maximum speed is insufficient when the valve is in its fourth state to simultaneously supply the second and third parts of the cooling circuit. In addition, it often happens that the determined speed is too high for the relevant part of the cooling circuit. Consequently, when the determined speed is too high, the pump consumes too much electrical energy unnecessarily, and when the determined speed is insufficient, the cooling of at least one prime mover is insufficient.

The invention is therefore intended in particular to improve the situation.

Presentation of the invention

For this purpose, it proposes in particular a control method intended to be implemented in a vehicle comprising a powertrain comprising first and second drive machines having first and second measured temperatures, and a cooling circuit in which a heat transfer fluid circulates and comprising, on the one hand, a first part comprising a pump and a valve having an inlet supplied with heat transfer fluid by this pump and first and second outlets, and, on the other hand, second and third parts connected respectively to the first and second outlets and capable of cooling the first and second drive machines respectively.

This control method is characterized by the fact that it comprises a step in which first and second pump speeds are determined, necessary for the respective cooling of the first and second driving machines, as a function respectively of the first and second measured temperatures, then the pump is operated according to a speed which is the greatest of these first and second determined speeds.

Thanks to the invention, the regime determined from the first and second regimes is much better adapted to the respective real needs of the second and third parts regardless of the state in which the valve is placed, and therefore the probability that the pump unnecessarily consumes too much electrical energy is significantly reduced.

The control method according to the invention may include other characteristics which may be taken separately or in combination, and in particular:

- in its step, the first regime can be determined in a first table establishing a correspondence between pump regimes necessary for cooling the first driving machine and first temperatures of the first driving machine, and the second regime in a second table establishing a correspondence between pump regimes necessary for cooling the second driving machine and second temperatures of the second driving machine;

- in the presence of the first option, in its step, the pump speeds, necessary for cooling the first or second driving machine, can be defined in relation to a predefined maximum pump speed;

- in its step, when the vehicle includes equipment having a third measured temperature and suitable for being cooled by the second part of the cooling circuit, a third pump speed can also be determined, necessary for cooling this equipment, as a function of this third measured temperature, then the pump can be operated according to a speed which is the greatest of the first, second and third determined speeds;

- in the presence of the last option, in its step, the third regime can be determined in a third table which establishes a correspondence between the pump regimes necessary for cooling the equipment and the third temperatures of this equipment;

- in the presence of the last sub-option, in its step, the pump speeds required for cooling the equipment can be defined in relation to a predefined maximum pump speed.

The invention also provides a computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing a control method of the type presented above, in a vehicle comprising a powertrain comprising first and second drive machines having first and second measured temperatures, and a cooling circuit in which a heat transfer fluid circulates and comprising, on the one hand, a first part comprising a pump and a valve having an inlet supplied with heat transfer fluid by this pump and first and second outlets, and, on the other hand, second and third parts connected respectively to the first and second outlets and capable of cooling the first and second drive machines respectively, to determine an operating speed of the pump.

The invention also proposes a control device intended to equip a vehicle comprising a powertrain comprising first and second drive machines having first and second measured temperatures, and a cooling circuit in which a heat transfer fluid circulates and comprising, on the one hand, a first part comprising a pump and a valve having an inlet supplied with heat transfer fluid by this pump and first and second outlets, and, on the other hand, second and third parts connected respectively to the first and second outlets and capable of cooling the first and second drive machines respectively.

This control device is characterized by the fact that it comprises at least one processor and at least one memory arranged to carry out the operations consisting of determining first and second pump speeds, necessary for the respective cooling of the first and second driving machines, as a function respectively of these first and second measured temperatures, then triggering operation of the pump according to a speed which is the greatest of these first and second determined speeds.

The invention also proposes a vehicle, possibly of the automobile type, and comprising a control device of the type presented above and a powertrain comprising first and second drive machines having first and second measured temperatures, and a cooling circuit in which a heat transfer fluid circulates and comprising, on the one hand, a first part comprising a pump and a valve having an inlet supplied with heat transfer fluid by this pump and first and second outlets, and, on the other hand, second and third parts connected respectively to the first and second outlets and capable of cooling the first and second drive machines respectively.

For example, the first prime mover may be of the thermal or electric type, and the second prime mover may be of the electric type.

Brief description of the figures

Other characteristics and advantages of the invention will appear on examining the detailed description below, and the attached drawings, in which:

schematically and functionally illustrates an exemplary embodiment of a vehicle comprising an electric GMP associated with a supervision computer and to which a cooling circuit is coupled, and a control device according to the invention,

schematically and functionally illustrates an exemplary embodiment of a supervision calculator comprising an exemplary embodiment of a control device according to the invention, and

schematically illustrates an example of an algorithm implementing a control method according to the invention.

Detailed description of the invention

The invention aims in particular to propose a control method, and an associated DC control device, intended to enable control of the speed rp of a pump PF of a cooling circuit CR coupled at least to the powertrain (or GMP) of a vehicle V.

In the following, it is considered, by way of non-limiting example, that the vehicle V is of the automobile type. For example, it is a car, as illustrated in the . But the invention is not limited to this type of vehicle. It concerns any type of vehicle (land, sea (or river) or air) comprising a powertrain (or GMP) comprising first and second driving machines capable of providing engine torque to move it, and a cooling circuit capable of cooling these first and second driving machines.

Furthermore, it is considered in the following, as a non-limiting example, that the vehicle V comprises a powertrain (or GMP) of the all-electric type (and therefore whose drive is provided exclusively by first MM1 and second MM2 electric motors). But the GMP could be of the hybrid type (and in this case it comprises a first thermal motor (MM1) and a second electric motor (MM2), or of the purely thermal type (and in this case it comprises first (MM1) and second (MM2) thermal motors).

Furthermore, it is considered in the following, as a non-limiting example, that the first MM1 and second MM2 electric motors are supplied with electrical energy by a main (or traction) battery BP, rechargeable during recharging phases. But the first MM1 and second MM2 electric motors could be supplied with electrical energy by a fuel cell.

We have schematically represented on the a vehicle V comprising an electric GMP transmission chain (and therefore with first MM1 and second MM2 electric motors), an on-board network RB, a service battery BS, a main (or traction) battery BP, a converter CV, a supervision computer CS, a cooling circuit CR, and a control device DC according to the invention.

The CV converter is of the DC/DC type (“Direct Current/Direct Current”). It is therefore responsible for converting a direct current from a first voltage to a second voltage.

The on-board network RB is an electrical supply network to which electrical (or electronic) equipment (or components) that consume electrical energy are coupled.

The service battery BS is responsible for supplying electrical energy to the on-board network RB, in addition, here, to that supplied by the CV converter powered by the main battery BP, and sometimes instead, here, of this CV converter. For example, this service battery BS can be arranged in the form of a very low voltage type battery (typically 12 V, 24 V or 48 V). It is rechargeable at least by the (current) converter CV. It is considered in the following, by way of non-limiting example, that the service battery BS is of the 12 V Lithium-ion type.

The transmission chain has a GMP which is, here, purely electric and therefore which comprises, in particular, first MM1 and second MM2 motor machines (here electric), first AM1 and second AM2 motor shafts, and first AT1 and second AT2 transmission shafts. Here, the term “electric motor machine” means an electric machine arranged so as to provide an output torque, defined by a torque setpoint, to move the vehicle V when it is supplied with electrical energy (here) by the main battery BP (we then speak of providing a positive output torque), as well as possibly to recover torque, for example in a regenerative braking phase (we then speak of providing a negative output torque).

The operation of the GMP is supervised by a CS supervision calculator.

The first driving machine MM1 is coupled to the first motor shaft AM1, to provide it with torque by rotational drive. This first motor shaft AM1 is here coupled to a first reducer RD1 which is also coupled to the first transmission shaft AT1, itself coupled to a first train T1 of driving wheels, preferably via a differential DV.

The second driving machine MM2 is coupled to the second motor shaft AM2, to provide it with torque by rotational drive. This second motor shaft AM2 is here coupled to a second reducer RD2 which is also coupled to the second transmission shaft AT2, itself coupled to a second drive wheel train T2, preferably via a differential DR.

It should be noted that the first train T1 is here located in the front part PVV of the vehicle V, and therefore the second train T2 is located in the rear part PRV of the vehicle V. But an inverse arrangement is possible.

The CV converter is also responsible, here, during the driving phases of the vehicle V, for converting part of the electric current stored in the main battery BP to supply the on-board network RB and the service battery BS (to recharge it) with converted electric current.

It should be noted, as illustrated without limitation on the , that the CV converter can be part of a CH charger also including a recharge calculator (not illustrated) responsible, at least, for controlling the recharges of the main BP battery.

The main (or traction) battery BP may, for example, comprise electrical energy storage cells, possibly electrochemical (for example of the lithium-ion (or Li-ion) or Ni-Mh or Ni-Cd type). Also for example, the main battery BP may be of the low voltage type (typically 450 V for illustration purposes). But it could be of the medium voltage or high voltage type.

It should also be noted that in the example illustrated without limitation on the the vehicle V also includes a distribution box BD to which the service battery BS, the converter CV and the on-board network RB are coupled. This distribution box BD is responsible for distributing in the on-board network RB the electrical energy stored in the service battery BS or produced by the converter CV, for the supply of the electrical components (or equipment) coupled to the on-board network RB according to power supply requests received (in particular from the CS supervision calculator of the GMP).

The cooling circuit CR comprises first P1, second P2 and third P3 parts. The first part P1 comprises a pump PF and a valve VC having an inlet supplied with heat transfer fluid by this pump PF and first and second outlets. The second part P2 is connected to the first outlet of the valve VC and is suitable for cooling at least the first driving machine MM1. The third part P3 is connected to the second outlet of the valve VC and is suitable for cooling the second driving machine MM2.

For example, and as illustrated without limitation on the , the first part P1 of the cooling circuit CR may also include a radiator RR responsible for cooling the heat transfer fluid. But this is not obligatory, because the radiator could be part of another device or system of the vehicle V.

This VC valve being a three-way type, it can take four states:

- a first closed state in which it prevents the supply of heat transfer fluid to the second P2 and third P3 parts of the cooling circuit CR,

- a second state in which it allows the supply of heat transfer fluid to the second part P2 of the cooling circuit CR, and prevents the supply of heat transfer fluid to the third part P3 of the cooling circuit CR,

- a third state in which it allows the supply of heat transfer fluid to the third part P3 of the cooling circuit CR, and prevents the supply of heat transfer fluid to the second part P2 of the cooling circuit CR, and

- a fourth state in which it allows the supply of heat transfer fluid to the second P2 and third P3 parts of the CR cooling circuit.

The placement of the valve VC in its first state is decided when the first tm1 and second tm2 temperatures measured respectively in the first MM1 and second MM2 driving machines are respectively lower than the first s1 and second s2 thresholds.

The placement of the VC valve in its second state is decided when the first tm1 and second tm2 measured temperatures are respectively higher than the first threshold s1 and lower than the second threshold s2.

The placement of the VC valve in its third state is decided when the first tm1 and second tm2 measured temperatures are respectively lower than the first threshold s1 and higher than the second threshold s2.

The placement of the VC valve in its fourth state is decided when the first tm1 and second tm2 measured temperatures are respectively higher than the first s1 and second s2 thresholds.

These decisions can, for example, be taken by the CS supervision calculator or the DC control device.

It is important to note that the PF pump has a predefined maximum speed rmax which is strictly higher than the maximum speed rm1 required to produce the maximum flow rate sometimes required by the second part P2 or the third part P3 of the cooling circuit CR. This predefined maximum speed rmax advantageously makes it possible to provide for the simultaneous needs of the second P2 and third P3 parts of the cooling circuit CR when the valve VC is placed in its fourth state. For example, rmax can be between 1.2*rm1 and 1.5*rm1. As an illustrative example, rmax can be equal to 1.3*rm1.

It should also be noted that in the example illustrated without limitation on the the second part P2 of the cooling circuit CR is also suitable for cooling equipment of the vehicle V, which is here the converter CV. But the second part P2 of the cooling circuit CR could be responsible for cooling only the first driving machine MM1. Furthermore, the equipment which is here cooled by the second part P2 of the cooling circuit CR could not be the converter CV. It can in fact be any equipment having an internal temperature varying temporally during operation and preferably located near the first driving machine MM1.

It should also be noted that when the second part P2 of the CR cooling circuit is also coupled to the equipment (here the CV converter):

- the placement of the valve VC in its second state is decided when the first measured temperature tm1 is higher than the first threshold s1 and/or the third measured temperature tm3 is higher than a third threshold s3 and the second measured temperature tm2 is lower than the second threshold s2, and

- the placement of the VC valve in its fourth state is decided when the first measured temperature tm1 is higher than the first threshold s1 and/or the third measured temperature tm3 is higher than the third threshold s3 and the second measured temperature tm2 is higher than the second threshold s2.

As mentioned above, the invention notably proposes a control method intended to enable the control of the speed rp of the pump PF of the cooling circuit CR coupled at least to the powertrain (or GMP) of a vehicle V.

This (control) method can be implemented at least partially by the DC control device (illustrated at least partially in FIGS. 1 and 2) which comprises for this purpose at least one processor PR1, for example a digital signal processor (or DSP), and at least one memory MD. This DC control device can therefore be produced in the form of a combination of electrical or electronic circuits or components (or “hardware”) and software modules (or “software”). For example, it can be a microcontroller.

The MD memory is RAM in order to store instructions for the implementation by the processor PR1 of at least part of the control method. The processor PR1 may comprise integrated (or printed) circuits, or several integrated (or printed) circuits connected by wired or wireless connections. An integrated (or printed) circuit is understood to mean any type of device capable of performing at least one electrical or electronic operation.

In the example illustrated non-limitingly in Figures 1 and 2, the control device DC is part of the supervision computer CS. But this is not obligatory. Indeed, the control device DC could include its own dedicated computer, which can then be coupled to the supervision computer CS, or could be part of another computer providing at least one other function within the vehicle V.

As illustrated without limitation on the , the (control) method, according to the invention, comprises a step 10-20 which is implemented, as soon as the GMP of the vehicle V is in operation.

Step 10-20 of the method comprises a sub-step 10 in which one (for example the DC control device) begins by determining at least a first speed r1 of the pump PF necessary for cooling the first motor machine MM1, as a function of the first measured temperature tm1, and a second speed r2 of the pump PF necessary for cooling the second motor machine MM2, as a function of the second measured temperature tm2.

Step 10-20 of the method also comprises a sub-step 20 in which the pump PF is operated (for example the DC control device triggers the operation of) at a speed rp which is the greater of the first r1 and second r2 speeds determined in sub-step 10.

Thanks to this determination of first r1 and second r2 regimes of the PF pump independent of each other, and to the fact that the PF pump can operate at a predefined maximum regime rmax higher than the maximum regime rm1 (necessary to produce the maximum flow rate sometimes required by the second part P2 or the third part P3 of the CR cooling circuit), the regime rp which is determined from the first r1 and second r2 regimes is much better adapted to the respective real needs of the second P2 and third P3 parts regardless of the state in which the VC valve is placed. The probability that the PF pump will consume too much electrical energy unnecessarily is therefore significantly reduced.

For example, in substep 10 of step 10-20 one (e.g. the DC control device) can determine the first regime r1 in a first correspondence table tc1 and the second regime r2 in a second correspondence table tc2.

The first correspondence table tc1 establishes a correspondence between the speeds of the pump PF required for cooling the first driving machine MM1 and the first temperatures of the first driving machine MM1. The second correspondence table tc2 establishes a correspondence between the speeds of the pump PF required for cooling the second driving machine MM2 and the second temperatures of the second driving machine MM2.

These first tc1 and second tc2 correspondence tables can be determined during the development phase of a vehicle similar to vehicle V, then they can be stored, for example, in the control device DC (or in the supervision computer CS).

Also for example, in sub-step 10 of step 10-20 the PF pump speeds required for cooling the first MM1 or second MM2 prime mover can be defined relative to the predefined maximum speed rmax of the PF pump. But this is not an obligation. Indeed, they could be defined relative to a theoretical maximum speed, for example slightly lower than the predefined maximum speed rmax.

Note that instead of using first tc1 and second tc2 lookup tables, one could use mathematical formulas to determine the first r1 and second r2 regimes.

It will also be noted that, when the vehicle V comprises equipment (here the CV converter) having a third measured temperature tm3 and capable of being cooled by the second part P2 of the cooling circuit CR, one (for example the DC control device) can also determine, in sub-step 10 of step 10-20, a third speed r3 of the pump PF, necessary for cooling this CV equipment, as a function of this third measured temperature tm3. In this case, in sub-step 20 of step 10-20 one can operate (for example the DC control device can trigger the operation of) the pump PF according to a speed rp which is the greatest of the first r1, second r2 and third r3 speeds determined in sub-step 10.

This also allows the needs of at least one other CV equipment coupled to the second part P2 of the CR cooling circuit to be taken into account.

For example, in substep 10 of step 10-20 one (for example the DC control device) can determine the third regime r3 in a third correspondence table tc3 which establishes a correspondence between regimes of the pump PF necessary for cooling the CV equipment and third temperatures tm3 of this CV equipment.

This third correspondence table tc3 can be determined during the development phase of a vehicle similar to vehicle V, then it can be stored with the first tc1 and second tc2 correspondence tables, for example in the control device DC (or in the supervision computer CS).

Also for example, in sub-step 10 of step 10-20 the PF pump speeds required for cooling the CV equipment can be defined relative to the predefined maximum speed rmax of the PF pump. But this is not an obligation. Indeed, they could be defined relative to a theoretical maximum speed, for example slightly lower than the predefined maximum speed rmax.

Note that instead of using a third correspondence table tc3, one could use at least one mathematical formula to determine the third regime r3.

It should also be noted, as illustrated without limitation on the , that the CS supervision calculator (or the DC control device calculator) may also comprise a mass memory MM1, in particular for storing the first tm1, second tm2 and possible third tm3 measured temperatures, and the state of the VF valve, as well as possible intermediate data involved in all its calculations and processing. Furthermore, this CS supervision calculator (or the DC control device calculator) may also comprise an input interface IE for receiving at least the first tm1, second tm2 and possible third tm3 measured temperatures, and the state of the VF valve to use them in calculations or processing, possibly after having formatted and/or demodulated and/or amplified them, in a manner known per se, by means of a PR2 digital signal processor. In addition, this CS supervision calculator (or the DC control device calculator) can also include an IS output interface, in particular to deliver a message containing each operating regime rp determined for the PF pump.

It will also be noted that the invention also proposes a computer program product (or computer program) comprising a set of instructions which, when executed by processing means of the electronic circuit (or hardware) type, such as for example the processor PR1, is capable of implementing the control method described above to determine the operating speed of the pump PF of the cooling circuit CR of the vehicle V.

Claims (10)

Control method for a vehicle (V) comprising a powertrain comprising first (MM1) and second (MM2) driving machines having first and second measured temperatures, and a cooling circuit (CR) in which a heat transfer fluid circulates and comprising i) a first part (P1) comprising a pump (PF) and a valve (VC) having an inlet supplied with heat transfer fluid by said pump (PF) and first and second outlets, and ii) second (P2) and third (P3) parts connected respectively to said first and second outlets and suitable for cooling said first (MM1) and second (MM2) driving machines respectively, characterized in that it comprises a step (10-20) in which first and second speeds of said pump (PF) are determined, necessary for the respective cooling of said first (MM1) and second (MM2) driving machines, as a function respectively of said first and second measured temperatures, then said pump (PF) is operated according to a speed which is the most large of the said first and second determined regimes. Method according to claim 1, characterized in that in said step (10-20) said first regime is determined in a first table establishing a correspondence between regimes of said pump (PF) necessary for cooling said first driving machine (MM1) and first temperatures of said first driving machine (MM1), and said second regime in a second table establishing a correspondence between regimes of said pump (PF) necessary for cooling said second driving machine (MM2) and second temperatures of said second driving machine (MM2). Method according to claim 2, characterized in that in said step (10-20) said pump speeds (PF) necessary for cooling said first (MM1) or second (MM2) driving machine are defined in relation to a predefined maximum speed of said pump (PF). Method according to one of claims 1 to 3, characterized in that in said step (10-20), when said vehicle (V) comprises equipment (CV) having a third measured temperature and suitable for being cooled by said second part (P2) of the cooling circuit (CR), a third speed of said pump (PF), necessary for cooling said equipment (CV), is also determined as a function of said third measured temperature, then said pump (PF) is operated according to a speed which is the greatest of said first, second and third determined speeds. Method according to claim 4, characterized in that in said step (10-20) said third regime is determined in a third table establishing a correspondence between regimes of said pump (PF) necessary for cooling said equipment (CV) and third temperatures of said equipment (CV). Method according to claim 5, characterized in that in said step (10-20) said pump speeds (PF) necessary for cooling said equipment (CV) are defined in relation to a predefined maximum speed of said pump (PF). Computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing the control method according to one of claims 1 to 6, in a vehicle (V) comprising a powertrain comprising first (MM1) and second (MM2) driving machines having first and second measured temperatures, and a cooling circuit (CR) in which a heat transfer fluid circulates and comprising i) a first part (P1) comprising a pump (PF) and a valve (VC) having an inlet supplied with heat transfer fluid by said pump (PF) and first and second outlets, and ii) second (P2) and third (P3) parts connected respectively to said first and second outlets and capable of cooling said first (MM1) and second (MM2) driving machines respectively, to determine an operating speed of said pump (PF). Control device (DC) for a vehicle (V) comprising a powertrain comprising first (MM1) and second (MM2) driving machines having first and second measured temperatures, and a cooling circuit (CR) in which a heat transfer fluid circulates and comprising i) a first part (P1) comprising a pump (PF) and a valve (VC) having an inlet supplied with heat transfer fluid by said pump (PF) and first and second outlets, and ii) second (P2) and third (P3) parts connected respectively to said first and second outlets and suitable for cooling said first (MM1) and second (MM2) driving machines respectively, characterized in that it comprises at least one processor (PR1) and at least one memory (MD) arranged to carry out the operations consisting in determining first and second speeds of said pump (PF), necessary for the respective cooling of said first (MM1) and second (MM2) driving machines, as a function respectively of said first and second temperatures measured, then to trigger operation of said pump (PF) according to a speed which is the greatest of said first and second determined speeds. Vehicle (V) comprising a powertrain comprising first (MM1) and second (MM2) driving machines having first and second measured temperatures, and a cooling circuit (CR) in which a heat transfer fluid circulates and comprising i) a first part (P1) comprising a pump (PF) and a valve (VC) having an inlet supplied with heat transfer fluid by said pump (PF) and first and second outlets, and ii) second (P2) and third (P3) parts connected respectively to said first and second outlets and capable of cooling said first (MM1) and second (MM2) driving machines respectively, characterized in that it further comprises a control device (DC) according to claim 8. Vehicle according to claim 9, characterized in that said first drive machine (MM1) is of the thermal or electric type, and said second drive machine (MM2) is of the electric type.