FR3135425A1 - MONITORING THE OPERATION OF AN ELECTRIC POWER MACHINE OF A VEHICLE - Google Patents

Abstract

A monitoring method is implemented in a vehicle comprising an electric driving machine providing an estimable output torque and periodically measuring an internal temperature. This method comprises a step (10-60) in which, when at least one internal temperature measurement is not contained in a chosen temperature interval, a chosen limitation of the output torque to be supplied is imposed, and we estimate periodically the output torque supplied, and, when in addition at least one estimate of the output torque does not respect this imposed limitation, the use of the electric motor machine is temporarily prohibited. Figure 3

Description

MONITORING THE OPERATION OF AN ELECTRIC POWER MACHINE OF A VEHICLE Technical field of the invention

The invention relates to vehicles comprising an electric driving machine forming part of a powertrain, and more specifically the monitoring within such vehicles of the operation of this electric driving machine.

State of the art

Certain vehicles, possibly of the automobile type, include a powertrain (or GMP) comprising an electric driving machine supplied with electrical energy, for example by a main (or traction) battery or by a fuel cell.

In the aforementioned vehicles, the electric driving machine is generally an electric motor comprising a rotor and a stator. When such an electric motive machine is in operation, for example to provide (positive) output torque for the wheels of a train of its vehicle, its stator consumes electrical energy from the main battery to create a magnetic field intended to rotate the rotor. Consequently, in operation the stator rises in temperature, and for it to operate correctly, without risk of degradation, its temperature must remain within a chosen temperature range.

The internal temperature of the electric motor machine, and more precisely of the stator, is therefore monitored by periodic comparison with the chosen threshold of its measurements (performed periodically by at least one internal sensor). Thus, when the internal temperature measurement is no longer contained within a chosen temperature interval, preferably for a period greater than a chosen threshold, a chosen limitation of the output torque to be provided is imposed. In other words, the electric motor machine is forced to operate in a degraded mode (or in English "limp home") in which the output torque that it is authorized to provide is limited, in order to avoid a degradation of the electric driving machine, or even the outbreak of a fire, and thus protect the vehicle and its passengers. At the same time, when the electric driving machine is associated with a thermal regulation circuit (allowing it to be cooled or heated as needed), this thermal regulation circuit is operated so that the internal temperature measurement becomes contained within the chosen temperature range as quickly as possible.

Sometimes, it may happen that the limitation of the output torque is not effective and/or that the thermal regulation circuit does not manage to bring the internal temperature back into the chosen temperature range (for example due to a malfunction ). In the above-mentioned situations, continued use of the electric drive machine may cause damage to this electric drive machine, or even the outbreak of a fire, which is potentially dangerous for the vehicle and its passengers.

Currently, there is no known solution making it possible to determine whether the operation of the electric motor machine is correct (or normal) during a phase of limitation of its output torque (or limp home). Consequently, the invention aims in particular to improve the situation.

Presentation of the invention

It proposes in particular for this purpose a monitoring method, on the one hand, intended to be implemented in a vehicle comprising an electric driving machine providing an estimable output torque and periodically subject to a temperature measurement internal, and, on the other hand, comprising a step in which, when at least one internal temperature measurement is not contained in a chosen temperature interval, a chosen limitation is imposed on the output torque to be supplied.

This monitoring method is characterized by the fact that in its step the output torque supplied is periodically estimated, and when in addition at least one estimate of the output torque does not respect the limitation imposed, the use of the electric driving machine.

Thanks to the invention, it is now possible to detect an operating problem of the electric motor machine during a phase of limitation of its output torque (or limp home), and act accordingly, at least by temporarily prohibiting the use of the electric driving machine.

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

- in its stage, the use of the electric motor machine can be temporarily prohibited when the successive output torque estimates do not respect the limitation imposed for a duration which is greater than a chosen threshold, and at the same time the measurements successive internal temperatures are outside the chosen temperature range;

- in its stage the limitation can consist either of a maximum torque chosen when the electric drive machine must provide a positive output torque, or in a minimum torque chosen when the electric drive machine must provide a negative output torque;

- in its stage the chosen temperature interval may include a minimum temperature between -60°C and -45°C and a maximum temperature between +90°C and +110°C;

- in its stage, in the event of a temporary ban on the use of the electric driving machine, it is also possible to carry out in the vehicle at least one complementary action which is chosen from a generation of an alert from a user of the vehicle the prohibition of use of the electric motor machine and a recording of at least one fault code representative of a problem of non-compliance with the limitation imposed;

- in its step we can re-authorize the use of the electric motor machine without the output torque limitation when the successive internal temperature measurements are again contained within the chosen temperature interval for a duration greater than another threshold chosen;

- in the presence of the last option, in its step we can choose the other threshold according to a sign, positive or negative, of the output torque to be provided by the electric motor machine.

The invention also proposes a computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing a monitoring method of the type of that presented above to monitor the operation of an electric driving machine fitted to a vehicle, providing an estimable output torque and periodically subject to an internal temperature measurement.

The invention also proposes a monitoring device, on the one hand, intended to equip a vehicle comprising an electric driving machine providing an estimable output torque and periodically subject to a measurement of an internal temperature, and, 'on the other hand, comprising at least one processor and at least one memory arranged to carry out the operations consisting, when at least one internal temperature measurement is not contained in a chosen temperature interval, in imposing a chosen limitation on the torque of output to be provided.

This monitoring device is characterized by the fact that its processor and memory are further arranged, in the event of imposition of a chosen limitation of the output torque, to carry out the operations consisting of periodically estimating the output torque supplied, and when 'in addition at least one estimate of the output torque does not respect the limitation imposed, to temporarily prohibit the use of the electric motor machine.

The invention also proposes a vehicle, possibly of the automobile type, and comprising, on the one hand, an electric driving machine providing an estimable output torque and periodically subject to a measurement of an internal temperature, and, On the other hand, a monitoring device of the type presented above.

Brief description of the figures

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

schematically and functionally illustrates an exemplary embodiment of a vehicle comprising a GMP, with an electric motor powered by a rechargeable main battery, and a monitoring device according to the invention,

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

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

Detailed description of the invention

The invention aims in particular to propose a monitoring method, and an associated monitoring device DS, intended to allow monitoring of the operation of the electric driving machine MME of a vehicle V, in particular during a phase of limitation of its couple out.

In what follows, we consider, by way of non-limiting example, that the vehicle V is of the automobile type. This is for example a car, as illustrated in the . But the invention is not limited to this type of vehicle. It concerns in fact any type of vehicle comprising a powertrain (or GMP) comprising an electric driving machine supplied with electrical energy, for example by a main (or traction) battery or by a fuel cell. Thus, it concerns, for example, land vehicles (utility vehicles, motorhomes, minibuses, coaches, trucks, motorcycles, road machinery, construction machinery, agricultural machinery, leisure machinery (snowmobile, kart), and road machinery. caterpillar(s), for example), boats and aircraft.

Furthermore, we consider in what follows, by way of non-limiting example, that the vehicle V comprises a powertrain (or GMP) of all-electric type (and therefore whose traction is ensured exclusively by at least one electric driving machine MRS). But the GMP could be of hybrid type (thermal and electric).

In addition, we consider in what follows, by way of non-limiting example, that the electric driving machine MME is supplied with electrical energy by a rechargeable main (or traction) battery during recharging phases. But the MME electric driving machine 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 an MME electric driving machine), an on-board network RB, a utility battery BS, a main (or traction) battery BP, a CV converter, and a device DS surveillance according to the invention.

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

The utility 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 converter RESUME. For example, this BS utility battery 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 via the CV (current) converter. We consider in the following, by way of non-limiting example, that the BS utility battery is of the 12 V Lithium-ion type.

The transmission chain has a GMP which is, here, purely electric and therefore which includes, in particular, an electric driving machine MME, an AM motor shaft, and an AT transmission shaft. Here we mean "electric driving machine" an electric machine arranged so as to provide torque to move the vehicle V when it is supplied with electrical energy (here) by the main battery BP (we then speak of supplying a torque positive output), as well as possibly recovering torque in regenerative braking (we then speak of providing a negative output torque).

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

The electric driving machine MME (here an electric motor) is here coupled to the main battery BP, in order to be supplied with electrical energy, as well as possibly to supply this main battery BP with electrical energy, in particular during braking recuperative.

We consider in what follows, by way of non-limiting example, that the electric motor machine MME comprises a rotor, a stator, and at least one CT sensor responsible for periodically carrying out mti measurements of its internal temperature. For example, the (each) CT sensor periodically performs mti measurements of the internal stator temperature. Also for example, this period can be equal to 5 ms.

Furthermore, this electric motor machine MME is coupled to the motor shaft AM, to provide it with an output torque by rotational drive. This motor shaft AM is here coupled to a reduction gear RD which is also coupled to the transmission shaft AT, itself coupled to a first train T1 (here of wheels), preferably via a differential D1.

This first train T1 is here located in the front part PVV of the vehicle V. But in a variant this first train T1 could be the one which is here referenced T2 and which is located in the rear part PRV of the vehicle V.

Note, as illustrated non-limitatively in the , that the electric driving machine MME can be associated with a thermal regulation circuit CRT, dedicated or shared in the vehicle V, and allowing it to be cooled or heated as needed so that its internal temperature is contained as much as possible within a range of temperatures it chosen. For example, the supervision computer CS can be responsible for controlling the operation of the thermal regulation circuit CRT as a function of the internal temperature measurements mti coming from the sensor CT and the temperature interval it. In this case, as soon as the internal temperature measurements mti are outside the temperature interval it, the supervision computer CS controls the operation of the thermal regulation circuit CRT to heat or cool the electric motor machine MME, as required. .

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

Note, as illustrated non-limitatively in 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 battery BP.

The main (or traction) battery BP can, for example, include 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 BP battery can be of the low voltage type (typically 450 V for illustration purposes). But it could be medium voltage or high voltage.

It should also be noted that the main battery BP is associated with a battery box BB which notably includes a battery calculator CB. This main battery BP and its battery box BB constitute a battery pack.

It will also be noted that in the example illustrated non-limitingly on the the vehicle V also includes a distribution box BD to which the utility battery BS, the CV converter 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 utility battery BS or produced by the converter CV, for powering the electrical components (or equipment) coupled to the on-board network RB depending on power requests received (in particular from the GMP CS supervision computer).

As mentioned above, the invention proposes in particular a monitoring method intended to allow monitoring of the operation of the electric motor machine MME, in particular during a phase of limitation of its output torque.

This (monitoring) method can be implemented at least partially by the monitoring device DS (illustrated at least partially in Figures 1 and 2) which comprises for this purpose at least one processor PR1, for example a digital signal (or DSP (“Digital Signal Processor”)), and at least one MD memory. This DS monitoring 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 memory MD is RAM in order to store instructions for the implementation by the processor PR1 of at least part of the monitoring process. The processor PR1 may include integrated (or printed) circuits, or several integrated (or printed) circuits connected by wired or non-wired connections. By integrated (or printed) circuit we mean any type of device capable of performing at least one electrical or electronic operation.

In the example illustrated without limitation in Figures 1 and 2, the monitoring device DS is part of the battery calculator CB (associated with the main battery BP). But this is not obligatory. Indeed, the monitoring device DS could include its own dedicated computer, which is then coupled to the management computer CG, or could be part of another on-board computer (for example the supervision computer CS or a management computer loaded to manage the operation of the MME electric driving machine).

As illustrated without limitation on the , the (monitoring) method, according to the invention, comprises a step 10-60 which is implemented when the GMP of the vehicle V is in operation, and in particular when the electric motive machine MME is in operation.

Step 10-60 of the method comprises a sub-step 20 in which, when at least one internal temperature measurement mti is not contained in the chosen temperature interval it, we (the monitoring device DS) impose a selected limitation of the output torque to be provided by the electric motor MME, and periodically estimates the output torque provided. Step 10-60 of the method also comprises a sub-step 50 in which, when in addition at least one estimate of the output torque ecs does not respect the limitation imposed in sub-step 20, we (the monitoring device DS) temporarily prohibits the use of the MME electric driving machine. It will be understood that the temporary ban is decided when at least one estimate of the DHW output torque does not respect the limitation imposed and that at the same time the successive internal temperature measurements mti are always outside the temperature interval it selected.

For example, and as illustrated without limitation on the , in order to make a decision in sub-step 50, we can provide a sub-step 40 of step 10-60 in which we (the monitoring device DS) compare each estimate of the output torque ecs to the limitation imposed . In this case, as indicated above, if an estimate of the output torque ecs respects the limitation imposed when the internal temperature measurement mti is not contained in the temperature interval it, we consider that there is no no operating problem of the electric motor machine MME, and therefore we (the monitoring device DS) returns to carry out sub-step 20. For example, to return the internal temperature to the temperature interval it, we (the CS supervision computer) can control the operation of the CRT thermal regulation circuit.

On the other hand in sub-step 50, when the internal temperature measurement mti is not contained in the temperature interval it and the estimate of the output torque ecs does not respect the limitation imposed, we (the device DS monitoring) considers that there is an operating problem with the MME electric drive machine during a phase of limitation of its output torque (or limp home), and therefore for safety reasons the use of the electric drive machine is temporarily prohibited MRS. This makes it possible to avoid damage to the MME electric driving machine, or even the outbreak of a fire, and therefore to protect the vehicle V and its passengers.

It will be noted that in sub-step 50 of step 10-60 we (the monitoring device DS) can temporarily prohibit the use of the electric motor machine MME when the estimates of the successive output torque ecs do not respect the limitation imposed for a duration which is greater than a first chosen threshold s1 and that at the same time the successive internal temperature measurements mti are outside the chosen temperature interval it. This option avoids taking into account a single erroneous or occasionally abnormal estimate of the DHW output torque (compared to the other DHW estimates made just before or just after) and/or a single erroneous or occasionally abnormal internal temperature measurement mti (compared to other mti measures carried out just before or just after) which would cause the immediate realization of a main action (namely the ban on the use of the MME electric motive machine).

For example, and as illustrated without limitation on the , in order to make a decision in sub-step 50, we can provide a sub-step 40 of step 10-60 in which we (the monitoring device DS) compare each internal temperature measurement mti to the minimum and maximum values of the chosen temperature interval. In this case, as indicated above, if an internal temperature measurement mti is in the temperature interval it we return to carry out substep 10, while if an internal temperature measurement mti is outside the temperature interval it temperatures it we continue with substep 20.

It will also be noted that in sub-step 40, we (the monitoring device DS) can optionally choose the first threshold s1 as a function of a sign, positive or negative, of the output torque to be supplied by the electric motor machine MME . In this case, in the case of supplying a positive output torque, a first value of first threshold s1 is used, and in the case of supplying a negative output torque, a second value of first threshold s1 is used.

For example, the first value of the first threshold s1 can be between 60 ms and 200 ms. As an illustrative example, the first value of the first threshold s1 can be equal to 80 ms. But other first values of first threshold s1 can be used. For example, the first value of the first threshold s1 can be chosen during the development phase of the vehicle V.

Also for example, the second value of the first threshold s1 can be between 60 ms and 200 ms. As an illustrative example, the second value of the first threshold s1 can be equal to 80 ms. But other second values of first threshold s1 can be used. For example, the second value of the first threshold s1 can be chosen during the development phase of the vehicle V.

Note that the first and second values of the first threshold s1 can be equal or different.

In order to determine the duration of an operating problem of the electric motor machine MME during a phase of limitation of its output torque, we (the monitoring device DS) can trigger in sub-step 40 a first time delay equal to the duration of the first threshold s1 chosen as soon as an estimate of the output torque ecs does not respect the limitation imposed for the first time, and when this duration of the first threshold s1 chosen expires (and we still have the estimate of the torque DHW output which does not respect the limitation imposed, without interruption), we decide in sub-step 50 to at least temporarily prohibit the use of the electric motor machine MME, of course on condition that at the same time the measurements successive internal temperature mti are outside the temperature interval it chosen.

It will also be noted that in sub-step 20 of step 10-60 we (the monitoring device DS) can impose a chosen limitation of the output torque when the successive internal temperature measurements mti are not contained in the interval of temperatures it chosen for a duration which is greater than a second threshold s2 chosen. This option makes it possible to avoid taking into account a single erroneous or occasionally abnormal internal mti temperature measurement (compared to the other mti measurements carried out just before or just after) which would cause the immediate realization of a chosen limitation of the output torque.

For example, and as illustrated without limitation on the , in order to make a decision in sub-step 20, we can provide a sub-step 10 of step 10-60 in which we (the monitoring device DS) compare each internal temperature measurement mti to the minimum and maximum values of the chosen temperature interval. In this case, as indicated above, if an internal temperature measurement mti is in the temperature interval it we return to carry out substep 10, while if an internal temperature measurement mti is outside the temperature interval it temperatures it we continue with substep 20.

It will also be noted that in sub-step 10 we (the monitoring device DS) can optionally choose the second threshold s2 as a function of the sign, positive or negative, of the output torque to be supplied by the electric motor machine MME. In this case, if a positive output torque is provided, a first value of second threshold s2 is used, and if a negative output torque is provided, a second value of second threshold s2 is used.

For example, the first value of the second threshold s2 can be between 60 ms and 200 ms. As an illustrative example, the first value of the second threshold s2 can be equal to 80 ms. But other first values of second threshold s2 can be used. For example, the first value of the second threshold s2 can be chosen during the development phase of the vehicle V.

Also for example, the second value of the second threshold s2 can be between 60 ms and 200 ms. As an illustrative example, the second value of the second threshold s2 can be equal to 80 ms. But other second values of second threshold s2 can be used. For example, the second value of the second threshold s2 can be chosen during the development phase of the vehicle V.

Note that the first and second values of the second threshold s2 can be equal or different.

In order to determine the duration of an internal temperature problem of the electric motor machine MME, we (the monitoring device DS) can trigger in substep 10 a second time delay equal to the duration of the second threshold s2 chosen as soon as an internal temperature measurement mti is not contained in the temperature interval it chosen for the first time, and when this duration of the second threshold s2 expires (and we still have the internal temperature measurement mti which is in outside the temperature interval it, without interruption), we decide in substep 20 to limit the output torque of the electric motor machine MME.

For example, in sub-step 20 of step 10-60 the limitation can consist either of a maximum torque cmax which is chosen when the electric motor machine MME must provide a positive output torque, or in a minimum torque cmin which is chosen when the MME electric motor must provide a negative output torque.

For example, the maximum torque cmax can be between +40 Nm and +60 Nm. As an illustrative example, the maximum torque cmax can be equal to +50 Nm. But other maximum torque values cmax can be used . For example, the value of the maximum torque cmax can be chosen during the vehicle development phase V.

Also for example, the minimum torque cmin can be between -40 Nm and -60 Nm. As an illustrative example, the minimum torque cmin can be equal to -50 Nm. But other minimum torque values cmin can be used. For example, the value of the minimum torque cmin can be chosen during the development phase of the vehicle V.

Also for example, in substep 10 of step 10-60 the temperature interval it chosen may include a minimum temperature tmin which is between -60°C and -45°C and a maximum temperature tmax which is between +90°C and +110°C. As an illustrative example, the minimum temperature tmin can be equal to approximately -50°C, and the maximum temperature tmax can be equal to approximately +100°C.

It will also be noted that in sub-step 50 of step 10-60, when the temporary ban on the use of the electric motor machine MME has been decided, it is also possible to carry out (the monitoring device DS can trigger the implementation ) in the vehicle V at (at) least one complementary action which is chosen from a generation of an alert of a user (or passenger) of the vehicle V of this prohibition of use of the electric motor machine MME and a recording of at least one fault code representing a problem of non-compliance with the imposed limitation.

The user of the vehicle V can be alerted, for example, by means of a lit indicator light (for example on the dashboard or the charging plate which includes the CN charging connector) and/or a message displayed on at least one screen of the vehicle V (for example on the dashboard or a central instrument panel) or on the screen of a smart phone (or “smartphone”) of the user, and/or broadcast by at least one speaker of the vehicle V or this smartphone.

The recording of at least one fault code representative of a problem of non-compliance with the imposed limitation is intended to facilitate the search for the origin of a ban on the use of the MME electric motor machine by a technician. an after-sales service, and to allow this technician (and to solve the problem and to inform the user of the vehicle V of the origin of such a ban.

For example, and as illustrated without limitation on the , the monitoring device DS can estimate in a sub-step 30 of step 10-60 the output torque ecs as a function of a voltage us on the output terminals of the electric motor machine MME, of a current ism delivered at the output of the electric driving machine MME, the rotation speed w of the rotor of the electric driving machine MME, the internal temperature mti of the stator, and the current taken by the electric driving machine MME (here in the main battery BP ).

Indeed, as those skilled in the art know, the estimate of the output torque ecs is given by the equation ecs = (us * ism * µ) / w. µ is an efficiency coefficient of the electric driving machine MME which is determined using the rotation speed w of the rotor of the electric driving machine MME, the internal temperature mti of the stator, the current taken by the electric driving machine MME (here in the main battery BP) and the voltage us across the terminals of the electric driving machine MME.

The previous equation results from the fact that the electric power pelec received by the electric motor machine MME on its input terminals is equal to the product (us * is), and that the electric motor machine MME provides at output a mechanical power pméca which is equal to the product (ecs * w) but also to the product (pelec * µ), and that consequently we have the equation (ecs * w) = (us * ism * µ).

It will also be noted that step 10-60 may also include a sub-step 60 in which it is considered that an operating problem of the electric motor machine MME (non-compliance with the imposed limitation) previously detected is no longer present. when the successive internal temperature measurements mti are again contained in the chosen temperature interval it for a duration which is greater than a third (or other) chosen threshold s3. In this case, we (the DS monitoring device) re-authorizes the use of the MME electric motor machine (previously prohibited), without the output torque limitation. Preferably, we also stop generating an (the DS monitoring device stops triggering the generation of a) alert for the user (when this additional action is planned).

It will also be noted that in sub-step 60 of step 10-60 we (the monitoring device DS) can possibly choose the third (or other) threshold s3 depending on the sign, positive or negative, of the output torque in front of be supplied by the MME electric driving machine.

In this case, if a positive output torque is provided, a first value of third threshold s3 is used, and if a negative output torque is provided, a second value of third threshold s3 is used.

For example, the first value of the third threshold s3 can be between 60 ms and 200 ms. As an illustrative example, the first value of the third threshold s3 can be equal to 80 ms. But other first values of third threshold s3 can be used. For example, the first value of the third threshold s3 can be chosen during the development phase of the vehicle V.

Also for example, the second value of the third threshold s3 can be between 60 ms and 200 ms. As an illustrative example, the second value of the third threshold s3 can be equal to 80 ms. But other second values of third threshold s3 can be used. For example, the second value of the third threshold s3 can be chosen during the development phase of the vehicle V.

Note that the first and second values of the third threshold s3 can be equal or different.

We can also envisage automatically re-authorizing the use of the electric motive machine MME (previously prohibited), without the limitation of output torque, after waking up the vehicle V subsequent to its falling asleep in the presence of prohibited use.

Note also, as illustrated non-limitatively in the , that the battery calculator CB (or the dedicated calculator of the monitoring device DS) can also include a mass memory MM1, in particular for the temporary storage of each internal temperature measurement mti, each voltage us on the output terminals of the electric driving machine MME, of each current ism delivered at the output of the electric driving machine MME, of each rotation speed w of the rotor of the electric driving machine MME, and of each current taken by the electric driving machine MME, and possible intermediate data involved in all its calculations and processing. Furthermore, this CB battery calculator (or the dedicated calculator of the DS monitoring device) can also include an IE input interface for receiving at least the internal temperature measurement mti, the voltage us, the current is, the rotation speed w, and the current taken by the electric motor machine MME, to use them in calculations or treatments, possibly after having shaped them and/or demodulated and/or amplified, in a manner known per se, by means a PR2 digital signal processor. In addition, this CB battery calculator (or the dedicated calculator of the DS monitoring device) can also include an IS output interface, in particular to deliver output torque limitation orders, temporary ban orders on the use of the MME electric motor machine, user alert messages, and messages containing a fault code.

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 monitoring method described above to monitor the operation of the electric motive machine MME of the vehicle V.

Claims (10)

A monitoring method for a vehicle (V) comprising an electric prime mover (MME) providing an estimable output torque and periodically measuring an internal temperature, said method comprising a step (10-60) in which, when at least one internal temperature measurement is not contained in a chosen temperature interval, a chosen limitation is imposed on said output torque to be supplied, characterized in that in said step (10-60) we estimate periodically said output torque provided, and when in addition at least one estimate of the output torque does not respect said imposed limitation, the use of said electric motor machine (MME) is temporarily prohibited. Method according to claim 1, characterized in that in said step (10-60) the use of said electric motor machine (MME) is temporarily prohibited when said successive output torque estimates do not respect said limitation imposed for a longer duration at a chosen threshold and that at the same time said successive internal temperature measurements are outside said chosen temperature interval. Method according to claim 1 or 2, characterized in that in said step (10-60) said limitation consists either of a maximum torque chosen when said electric motor machine (MME) must provide a positive output torque, or of a minimum torque chosen when said electric motor machine (MME) must provide a negative output torque. Method according to one of claims 1 to 3, characterized in that in said step (10-60) said chosen temperature interval comprises a minimum temperature between -60°C and -45°C and a maximum temperature between + 90°C and +110°C. Method according to one of claims 1 to 4, characterized in that in said step (10-60), in the event of a temporary ban on the use of said electric motor machine (MME), ( V) at least one complementary action chosen from a generation of an alert from a user of said vehicle (V) of said prohibition of use of said electric motor machine (MME) and a recording of at least one fault code representative of a problem of non-compliance with said imposed limitation. Method according to one of claims 1 to 5, characterized in that in said step (10-60) the use of said electric motor machine (MME) is re-authorized without said limitation when said successive internal temperature measurements are again contained in said chosen temperature interval for a duration greater than another chosen threshold. Method according to claim 6, characterized in that in said step (10-60) said other threshold is chosen as a function of a sign, positive or negative, of said output torque to be provided by said electric motor machine (MME). Computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing the monitoring method according to one of claims 1 to 7 to monitor the operation of a electric motor machine (MME) fitted to a vehicle (V), providing an estimable output torque and periodically subject to an internal temperature measurement. Monitoring device (DS) for a vehicle (V) comprising an electric motor machine (MME) providing an estimable output torque and periodically subject to measurement of an internal temperature, said monitoring device (DS) comprising at least one processor (PR1) and at least one memory (MD) arranged to carry out the operations consisting, when at least one internal temperature measurement is not contained in a chosen temperature interval, of imposing a chosen limitation of said couple output to be provided, characterized in that said processor (PR1) and memory (MD) are further arranged, in the event of imposition of a chosen limitation of said output torque, to carry out the operations consisting of periodically estimating said torque output provided, and when in addition at least one estimate of the output torque does not respect said imposed limitation, to temporarily prohibit the use of said electric motor machine (MME). Vehicle (V) comprising an electric motor machine (MME) providing an estimable output torque and periodically subject to a measurement of an internal temperature, characterized in that it further comprises a monitoring device (DS) according to claim 9.