FR3055658A1 - METHOD FOR AIDING REGENERATION OF A PARTICLE FILTER IN AN EXHAUST LINE - Google Patents

Abstract

The invention relates to a method for assisting a regeneration of a particulate filter (3) of an exhaust line (1) of an internal combustion engine (2). Conductor profiles are defined and their influence is more or less favorable to a regeneration behavior and, for the conductor profiles being the least favorable to the holding of a regeneration, the particulate filter (3) is subjected to the auxiliary heating as long as the temperature of the particulate filter (3) is less than or equal to a temperature threshold value.

Description

Holder (s): PEUGEOT CITROEN AUTOMOBILES SA Société anonyme.

Extension request (s)

Agent (s): PEUGEOT CITROEN AUTOMOBILES SA Public limited company.

54) METHOD FOR HELPING AN EXHAUST REGENERATION.

OF A PARTICLE FILTER IN A LINE

FR 3 055 658 - A1 çV) The invention relates to a method of assisting in the regeneration of a particle filter (3) of an exhaust line (1) of an internal combustion engine (2) of one. Conductor profiles are defined and their influence is more or less favorable for holding a regeneration and, for the conductor profiles being the least favorable for holding a regeneration, the particle filter (3) is subjected to additional heating as long as the temperature of the particulate filter (3) is less than or equal to a temperature threshold value.

METHOD FOR ASSISTING A REGENERATION OF A PARTICLE FILTER IN AN EXHAUST SYSTEM The invention relates to a method for assisting in the regeneration of a particulate filter present in an exhaust line of an internal combustion engine of a motor vehicle, this aid being provided by an auxiliary heating of the particle filter in addition to the heating of the particle filter by the exhaust gases discharged from the internal combustion engine by the exhaust line.

The particulate filter concerned by the present invention may be a particulate filter present in an exhaust line of an internal combustion engine fueled by motor vehicle fuel, but the particulate filter may also be a particulate filter. for a Diesel engine.

For a diesel internal combustion engine, regulations impose the presence of a particulate filter in an exhaust line of a Diesel vehicle for several years.

[0004] The standards antipollution come, particularly in Europe with the upcoming regulatory Euro 6 emissions ^2nd stage, harden strongly the threshold limits for particulate emissions from the engines to Direct Injection engines of petrol or controlled ignition.

Compliance with such regulations could require the use of a particle filter in the exhaust line of such engines. Such a particle filter for petrol engines, also commonly called GPF for the English name of "Gasoline Particle Filter", that is to say a petrol particle filter, is relatively similar to those used for Diesel engines but its characteristics are adapted so as not to penalize performance or consumption.

A particle filter, both for a gasoline engine or a diesel engine, fills with particles and must be emptied at regular intervals. A particle filter is then regenerated during which the particles are burned. A strong increase in the temperature in the exhaust line near the particulate filter is then desired.

Heating continues then until the regeneration is not detected as complete. A particle filter therefore performs its regenerations passively in the presence of a high level of oxygen where self-combustion of the particles takes place.

[0008] Thus, in order not to generate a problem of excessive back pressure or of risk of premature breakage, it is necessary to regularly regenerate the particle filter. This regeneration therefore requires the simultaneous presence in the particle filter, on the one hand, of a high temperature, advantageously greater than 600 ° C. and, on the other hand, of oxygen, the necessary proportion of oxygen depending on the temperature of the particulate filter and essentially determining a more or less long duration of the regeneration. These two conditions are contradictory and are not easy to obtain simultaneously.

[0009] In fact, an increase in temperature is often obtained by post-injection of fuel into the engine. At this time the oxygen concentration in the exhaust line is relatively low. When the accelerator pedal driver's foot is lifted, oxygen is supplied to the exhaust line but this contributes to a limited drop in the temperature of the exhaust line and of the particulate filter in line.

It is important to have both the fuel, that is to say the particles retained in the particulate filter, and the oxidizer, that is to say oxygen, in sufficient quantities. If one of the fuel or oxidizer is absent or present in a limited quantity, then combustion will not take place or will take place in an unsatisfactory manner.

Document FR-A- 2 806 125 describes a device and a method for regenerating a particle filter of an internal combustion engine. During the regeneration phase of the particulate filter determined by the electronic control system thanks to the level of loading of the particulate filter as well as the operating point of the engine, the particulate filter is heated by means of electric heating means supplied by the discharge of a capacitor and a battery or alternator.

This document teaches that it is possible to use an auxiliary heating of a particulate filter other than by the exhaust gases. The electrically heated particulate filter is connected to an electronic control system allowing it to determine, thanks to the level of loading of the particulate filter and the engine operating point, whether regeneration is necessary.

On the other hand, the regenerations of a particulate filter are dependent on the driving mode, for example the type of journeys, the driving style and various parameters such as the outside temperature and / or the engine temperature. For example, if the vehicle is used frequently for only short journeys, the regenerations will not be launched in an optimal way and may be interrupted firstly because on a short journey, the particle filter can hardly reach the temperature required to launch. a regeneration, this after a long period of heating during which no regeneration is possible and that secondly, the vehicle will be stopped before the regeneration is finished.

Therefore, the problem underlying the present invention is to implement a backup heater on a particulate filter in a motor vehicle exhaust line which is adapted to the vehicle driving mode so that regeneration of the particulate filter is optimized.

To achieve this objective, there is provided according to the invention a method of assisting in the regeneration of a particulate filter of an exhaust line of an internal combustion engine of a motor vehicle, the particulate filter which must undergo regular regeneration (in order to burn the particles which it retains and to empty it), (the filter being able in particular to be sequentially subjected to an additional heating in addition to the heating effected by the exhaust gases s 'flowing through the exhaust line during regenerations), the process defining conductor profiles and estimating their influence more or less favorable to the holding of a regeneration: for the driver profiles being the least favorable to the holding of regeneration, the particulate filter is subjected to additional heating as long as the temperature of the particulate filter is less than or equal to a temperature threshold value cross out.

The technical effect is to obtain additional heating individualized to a specific driver profile historically followed by the driver of the vehicle. For driver profiles least favorable to the implementation of a regeneration, for example for a particulate filter not being at a sufficiently high temperature or for a journey of the vehicle likely to be short taking into account the history of the routes generally followed by the vehicle, it is necessary to hasten the progress of a regeneration, the auxiliary heating making it possible to provide a solution for these less favorable driver profiles.

If the closest prior art had proposed to use a backup heater, this had not been done to comply with the specific driving situation of the vehicle, driving situation as the present invention intends to anticipate through a history of driver profiles which are each specific to a given motor vehicle.

The invention consists in using a particle filter which can be heated so as to raise it to temperature without impacting the rest of the operation of the engine due to the auxiliary heating other than heating the particle filter by exhaust gas. This creates the conditions for faster regeneration. This regeneration can be immediate in Diesel or as soon as the driver takes his foot off the accelerator for a petrol engine. The backup heater can be kept during regeneration to reduce the regeneration time.

Advantageously, the conductor profiles being the least favorable are, taken individually or in combination, conductor profiles performing short journeys which do not allow completion of a regeneration during a short journey, conductor profiles mainly driving city and driver profiles starting under cold weather conditions below 10 ° C.

By "short" journey is understood a journey of at most 10 km, in particular at most 5 km. "Cold" climatic conditions include an outside temperature of at most 10 ° C.

Short path profiles do not allow, on the one hand, to reach a start of regeneration temperature due to the lack of rolling of the motor vehicle. In addition, even when this regeneration start temperature, advantageously around 650 ° C. is reached, the problem arises of stopping the vehicle due to a short journey, this not making it possible to finish the regeneration. Very cold temperatures will increase the time it takes to reach the start of regeneration temperature and are also unfavorable. Driving in the city does not provide stable engine operating parameters and hinders the smooth running of a regeneration.

Advantageously, learning of the driver profiles is done according to at least one of the following parameters, taken individually or in combination: a predetermined number of days passed, a total distance traveled, an average driving speed during the predetermined number of days elapsed or the distance traveled, an association of a number of distances traveled between two starts less than a first lower mileage threshold and a number of distances traveled between two starts greater than a second upper mileage threshold, an outside temperature and an internal combustion engine temperature at start-up estimated according to a temperature of the engine coolant.

Among these parameters which can be taken in combination, the fact of counting, on the one hand, the short paths not allowing regeneration and, on the other hand, the long paths which may allow them, will give a modulation of a driver profile unfavorable to regeneration. For a driver profile mainly comprising short journeys, the presence of a long journey interspersed between these short journeys can make this profile less unfavorable, since regeneration will then be possible during the long journey. This characteristic makes it possible to take account of the insertion of a long journey into a series of short journeys and to reduce the unfavorable nature of the associated driver profile.

Advantageously, it is also taken into account the current driving conditions and / or the amount of particles retained in the particle filter. Thus, the process is updated in real time during taxiing. The quantity of particles retained in the particle filter gives an indication as to initiating a regeneration by considering the conductor profile. For a very unfavorable conductor profile, regenerations will be launched even if the particle filter is not completely filled to have regenerations of relatively short duration instead of having a long regeneration emptying a completely filled particle filter.

Advantageously, for a particle filter retaining an amount of particles close to a predetermined maximum limit retained in the particle filter, for conductors starting under cold climatic conditions or for conductors making predominantly short journeys not allowing completion of a regeneration during a short journey with, in the latter two cases, a calibrable value of the quantity of particles in the particle filter at least greater than one tenth of the predetermined maximum limit retained in the particle filter, this value adjustable depending on the average distance between two starts according to the associated conductor profile, the auxiliary heating of the particulate filter is activated from the start.

This calibratable value can be adapted according to the driver profile. For example, for a very unfavorable conductor profile, this value will be relatively low, while for a less unfavorable conductor profile, this value may be higher.

Advantageously, the backup heater is an electric heater. Such a backup heater is the fastest and the least bulky, with electric power sources such as a battery, an electric generator or an alternator being present in the vehicle.

The invention relates to a set of a particulate filter in an exhaust line of an internal combustion engine of a motor vehicle and its supervisor managing regeneration, characterized in that it implements such a regeneration aid method, the supervisor comprising or cooperating with means for memorizing and determining conductor profiles, means for qualifying a conductor profile as being critical for the regeneration of a particulate filter and means for actuating at least one auxiliary heating element of the particle filter when a conductor profile is qualified as a critical profile for regeneration.

Supervisors conforming to the state of the art could not take into account all the life situations of the vehicle. With a memorization of driver profiles specific to the vehicle, it can be extrapolated the upcoming driving conditions or at least it can be estimated these driving conditions. A supervisor according to the present invention can take into account the quantity of particles stored in the filter and the current driving conditions or even the supposed short-term conditions.

The present invention has an influence on the occurrences of regeneration by increasing these occurrences. The implementation of the present invention avoids applying degraded modes or even sending a vehicle to after-sales service.

During the regenerations, according to the invention, it is obtained a suppression of the impacts on the approval and a limitation of the impacts on the consumption. A positive impact on emissions can also be envisaged.

Advantageously, said at least one heating element is an electric heating element heating a ceramic contour of the particle filter or heating an interior of the ceramic of the particle filter.

. The temperature rise being electrically does not cause any modification of the engine operating point and therefore has no impact on the approval.

The invention relates to a motor vehicle provided with an internal combustion engine equipped with an exhaust line comprising a particle filter, the engine being controlled by a control unit, the particle filter being associated with a supervisor by forming an assembly, characterized in that the assembly is as previously described, the supervisor cooperating with the control unit command to manage the regenerations of the particle filter.

Advantageously, said at least one auxiliary heating element is electric and is supplied directly by an alternator driven by a crankshaft of the internal combustion engine or by a battery rechargeable by the alternator.

The impact on consumption exists because the necessary electric power will have to be compensated. But if we directly use the power coming from the alternator, the choice of the operating point on which this strategy is activated makes it possible to limit losses and therefore reduce the impact on consumption. If a rechargeable battery is used, this can be combined with recharging the battery, which can be done under optimal conditions and can guarantee up to an impact on zero consumption.

Other characteristics, objects and advantages of the present invention will appear on reading the detailed description which follows and with regard to the attached drawing given by way of non-limiting example and in which:

- Figure 1 is a schematic representation of an internal combustion engine assembly provided with an exhaust line with a control-command unit, this assembly can implement a regeneration process of a particulate filter according to the present invention , the regeneration being controlled by a supervisor.

It should be borne in mind that the figure is given by way of example and is not limitative of the invention. It constitutes a schematic representation of principle intended to facilitate the understanding of the invention and is not necessarily on the scale of practical applications. In particular, the dimensions of the various elements illustrated are not representative of reality.

For example, the oxidation catalyst or three-way catalyst and the particle filter are shown integrated in the same brick in Figure 1, which is not necessarily the case, these two elements can be separated the one from the other, the catalyst (oxidation or three-way) being upstream with respect to the particle filter by referring to the path of the gases in the exhaust line.

It will first be detailed with reference to Figure 1 an assembly comprising an engine with an exhaust line 1 and a control unit 6. The exhaust line 1 includes a filter 3 with particles and advantageously a catalyst 4, frequently an oxidation catalyst or a three-way catalyst. The particulate filter 3 may or may not be impregnated with a catalyst for selective catalytic reduction or for a three-way function.

Such a particle filter 3 fills with particles and must be emptied at regular intervals. There is then a regeneration of the particle filter 3 during which the particles are burned. A strong increase in temperature is therefore desired in the exhaust line 1 near the particulate filter 3. Heating then continues until regeneration is not detected as complete.

A particle filter 3 therefore performs its regenerations passively in the presence of a high level of oxygen where self-combustion of the particles takes place. A regeneration supervisor 7 associated with the particle filter 3 is in charge of piloting the regenerations.

Catalyst 4 can be a Diesel oxidation catalyst also known by the acronym DOC for the Anglo-Saxon name of Diesel Oxidation Catalyst or a three-way catalyst for a gasoline engine. Other elements of depollution can however be present in this line 1, for example but not only elements of selective catalytic reduction. In FIG. 1, the catalyst 4 and the gasoline particle filter 3 are grouped together in the same system, which is not compulsory.

The gasoline particulate filter 3 is advantageously in the form of a porous system composed of cordierite, mullite or silicon carbide or the like where the channels are plugged alternately at each end. It is characterized by a volume, a quantity of channels, a wall thickness and a porosity. The particulate filter 3 is advantageously positioned downstream of the catalyst 4. This particulate filter 3 can be impregnated with a catalyst to perform a selective catalytic reduction or a three-way function (CO and HC oxidation and NOx reduction) but this doesn’t is not mandatory.

Conventionally, there may be provided at least one oxygen probe or lambda probe, in Figure 1 two oxygen probes 5, 5a. A 5a of these two lambda probes 5, 5a can be placed in the exhaust line 1 between an exhaust manifold of the engine 2 and the catalyst 4. Its measurements can be transmitted to an injection computer provided in a control- control 6 of engine 2 in order to provide the possibility of determining the proportion of the air-fuel mixture for which the efficiency of engine 2 is optimal. These characteristics are not essential for the implementation of the present invention.

The other oxygen sensor 5 can be provided downstream of the catalyst 4 and of the particle filter 3 in the exhaust line 1. The main function of this oxygen sensor 5 downstream of the particle filter 3 is, in addition to the oxygen sensor 5a disposed upstream of the particle filter 3, to make it possible to evaluate the effectiveness of the particle filter 3 and of the catalyst 4 permanently. Each oxygen sensor 5, 5a delivers richness information by means of a potential difference provided by the sensitive element which composes it.

Other measurement sensors, for example temperature sensors and / or pressure sensors may also be present on the exhaust line 1. All these measurements are sent to the control unit 6 responsible for the optimal functioning of the internal combustion engine and the depollution in the exhaust line 1 and some of these measurements are sent directly to the regeneration supervisor 7 associated with the filter 3 to parts or indirectly through the engine control unit 6.

As previously mentioned, the particle filter 3 undergoes frequent regenerations to be emptied of soot particles contained in the particle filter 3.

In Diesel, the presence of oxygen in the exhaust line 1 is permanent when the engine is running. It is therefore necessary to heat the particle filter 3 at the operating points for which this temperature rise is the least costly in terms of energy. If a given level of stored soot is exceeded, this heating can be applied whatever the operating point in order to avoid switching to degraded mode due to fouling and / or overloading of the filter 3 with particles.

In essence, the need to heat mainly concerns conductive profiles driving little or on very urban routes and not having the time or the conditions to reach the required temperature. For these profiles identified as critical, the heating of the particulate filter 3 can be activated from start-up in order to take advantage of each occurrence of the driver's accelerator kick-off and therefore the presence of oxygen to regenerate.

The particle filter 3 is associated with a supervisor 7. In FIG. 1, the supervisor 7 is shown with means for actuating an auxiliary heating, in the form of at least one electrical element of 8 additional heating. This can however be done by the control unit 6 responsible for the optimal functioning of the internal combustion engine 2 and the depollution in the exhaust line 1. Similarly, the supervisor 7 may or may not be integrated into the control unit 6.

According to the invention, there is provided a method of assisting in the regeneration of a particle filter 3 of an exhaust line 1 of an internal combustion engine 2 of a motor vehicle. Such a particle filter 3 must regularly undergo regeneration in order to burn the particles which it retains and to empty it.

As described in the closest state of the art, the filter 3 is sequentially subjected to additional heating in addition to the heating effected by the exhaust gases flowing through the exhaust line 1. This heating is used to obtain for the particle filter 3 a temperature sufficient to ensure regeneration, for example a temperature above 600 ° C, in particular a temperature of 650 ° C or more.

According to the invention, conductor profiles are defined and their influence is estimated to be more or less favorable for carrying out regeneration. For the conductor profiles being the least favorable for holding a regeneration, the particle filter 3 is subjected to additional heating as long as the temperature of the particle filter 3 is below a threshold temperature value.

This temperature threshold value can be the start of regeneration temperature that has previously been stored by a supervisor 7 of the particle filter 3 or a control-command unit of the internal combustion engine 2 being also responsible for monitoring the depollution in line 1 of exhaust. This value can be 650 ° C but this is not limiting.

There are indeed conductor profiles and outside temperatures or exhaust lines 1 which are less favorable to the holding of regenerations than others. For example without being limiting, the driver profiles being the least favorable can be associated with drivers making short journeys. These short journeys, for example less than 10 kilometers or even 5 kilometers, do not in fact allow a completion of a regeneration because they are too short for the engine 2 to heat up and also too short in duration for a regeneration to be carried out. end to end. This is also the case for drivers driving mainly in the city.

A second group which is particularly unfavorable for carrying out regeneration of the particulate filter 3 is associated with conductors starting under cold climatic conditions, for example below 10 ° G The lower the temperature, the more difficult it is to start a regeneration. Indeed, it takes longer for the engine 2 to start to heat up and all the elements of the exhaust line 1 and in particular the particle filter 3 are cold. This temperature of the filter can for example be the outside temperature, this just after a start-up takes place after a stop time during which the engine 2 has had time to cool, such a stop time being able to be greater than 90 minutes order of idea, but this is not limiting.

Furthermore, the lower the temperature, the more the particle emissions increase at startup and the filter fills quickly.

It is understood that a driver making very short journeys by very cold outside temperatures is the most problematic case for initiating regenerations. In this case, the backup heater is used to raise the temperature of the particulate filter 3, which is only possible by the exhaust gases after a too long period. In certain borderline cases, to prevent the temperature from falling below the minimum regeneration temperature during a regeneration, the auxiliary heating can also be maintained for the duration of the regeneration.

Learning of the driver profiles can be done according to at least one of the following parameters which can be used alone or in combination with one another. One of the parameters can be a predetermined number of days passed, for example 10 days, a month or any representative interval for such learning of driver profiles or a total distance traveled sufficient to know the habits of the driver.

It can be taken into account an average driving speed during the predetermined number of days passed or the distance traveled. The most critical driver profiles are those who will start the engine cold or even very cold and drive very few kilometers with their vehicle. The detection of these driver profiles can be done in several ways but the simplest seems to be to take into consideration a given past period of for example 10 days or a month and / or over a distance traveled.

An outside temperature and a temperature of the internal combustion engine 2 at start-up can be considered, the temperature of the engine 2 being advantageously estimated according to a temperature of the engine coolant 2. The outside temperature will have an impact at the start of starting on the rise in temperature of engine 2, an engine 2, the exhaust line 1 and the particle filter 3 taking longer to warm up the colder the outside temperature.

A particularly interesting parameter is a combination of a number of distances traveled between two starts less than a first lower mileage threshold and a number of distances traveled between two starts greater than a second upper mileage threshold.

For example, if a driver only makes short journeys of around 5 km without long journeys, he defines a conductive profile which is very unfavorable to the performance of regeneration of the particle filter 3. If long distances are interspersed between short journeys, for example a distance of 50 km or more, the driver profile is less unfavorable for carrying out regenerations, regeneration being able to take place during the driving of the long distance. As an idea, the first lower mileage threshold may be less than 10 kilometers and the second upper mileage threshold may be more than 20 kilometers, which is not limiting.

It can be envisaged to take into account a ratio between a number of distances traveled between two starts less than a first lower threshold and a number of distances traveled between two starts greater than a second upper threshold by adapting a coefficient or weight relative to the mileage traveled during each journey. The higher this ratio, the more critical the driver profile.

It is possible to determine a number of distances traveled between two starts greater than a second upper threshold which makes the driver profile less critical. In fact, the more long distances traveled, the less the driver profile is unfavorable for carrying out regenerations.

It is also taken into account the current driving conditions and / or the quantity of particles retained in the particle filter 3. According to a preferred embodiment of the invention, when a complete regeneration of the particle filter 3 is problematic to launch for conductor profiles, premature regenerations can be launched preventively so that the particle filter 3 is not too full of particles and that the regenerations thus launched take less time.

For a particle filter 3 retaining an amount of particles close to a predetermined maximum limit retained in the particle filter 3, a backup heater of the particle filter 3 is activated from the start. You should not waste time to start regeneration and therefore raise the temperature of the particulate filter 3 as quickly as possible, which the auxiliary heating does.

Activation of the auxiliary heating of the particle filter 3 from start-up can also be valid for a driver profile starting under cold climatic conditions or a driver profile mainly carrying out short journeys which do not allow completion of regeneration during a short trip with. In the latter two cases, a calibrable value of the quantity of particles can be defined in the particle filter 3 above which regeneration can be initiated.

This calibratable value may depend on the conductor profile and in particular on an average journey accomplished between two starts, according to the associated conductor profile, and is known to be less than the maximum value of quantity of particles in the particle filter 3, for which a regeneration must be started.

For example, this calibrable value can be at least greater than one tenth of the predetermined maximum limit retained in the particle filter 3 but can be calibrated to be precisely adapted to the type of particle filter 3 and the profile of driver. For example, for a driver making short journeys of 2 kilometers without long journey, this calibratable value will be chosen lower than for a driver making journeys of 8 kilometers or more and so on.

The invention relates to a set of a particle filter 3 in an exhaust line 1 of an internal combustion engine 2 of a motor vehicle and of its supervisor 7 managing regeneration.

The regeneration aid method described above is implemented by a supervisor 7 of the particle filter 3 in the exhaust line 1. This supervisor 7 includes or cooperates with means for storing and determining conductor profiles, means for qualifying a conductor profile as being critical for the regeneration of a particle filter 3 and actuation means for at least one auxiliary heating element 8 of the particle filter when a conductor profile is qualified as critical profile for regeneration.

Said at least one heating element 8 can be an electric heating element 8 heating a ceramic contour of the particle filter 3 or an interior of the ceramic of the particle filter 3. The heater (s) can heat the catalyst 4 and the particle filter 3 in common, but this is in no way compulsory.

The invention finally relates to a motor vehicle with the engine 2 being controlled by a control unit 6, the particle filter 3 being associated with a supervisor 7 by forming an assembly as previously described, the supervisor 7 cooperating with the control unit 6 to manage regeneration of the particulate filter 3.

The supervisor 7 of the particulate filter 3 can be integrated into the control unit 6 of the engine 2 responsible for the optimal operation of the engine 2 and the depollution of exhaust gases. It is also possible that the engine control unit 6 comprises at least part of the means for storing and determining driver profiles, means for qualifying a driver profile and means for actuating at least at least one auxiliary heating element 8 in association with the supervisor 7 of the particle filter.

There may be a heating element 8 like several heating elements

8. The auxiliary heating element (s) 8 may be electric and be supplied directly by an alternator driven by a crankshaft of the internal combustion engine 2 or by a battery rechargeable by the alternator. The alternator may have a pulley connected by an accessory belt to a crankshaft pulley. Finally, the auxiliary heating element or elements 8 may have an adjustable heating power.

Today there are in development heated catalysts. These catalysts, intended to treat conventional gaseous pollutants of the carbide monoxide, hydrocarbons or nitrogen oxides type, have a specific structure and composition which makes it possible to raise their temperature electrically according to commands from the control unit command 6 of the motor 2.

The invention can use a similar substrate structure, whatever the material, by adapting the porosity, the pore size, the cell density and the thickness of the walls and by blocking the channels alternately at the inlet and at the bottom. output to create a filter 3 which would have the desired filtration efficiency, for example 99% in Diesel or 70% in petrol.

The electrically heated particle filter 3 can be associated, on the one hand, with an electrical circuit on the one hand and, on the other hand, with the supervisor 7 or engine control computer 2 making it possible to manage the actuation of the heater.

For Diesel applications, it is known that the particle filters 3 are all associated with a complex supervisor 7 which seeks the best conditions under which it will be possible to cause regeneration but this supervisor 7 did not take into account the profiles driver. For a gasoline engine 2, in addition to passive regeneration conditions, for example during a lifting of the driver's foot from the accelerator pedal, provision is made to associate a supervisor 7 with the particle filter 3.

Supervisors 7 may not take into account all life situations and for certain driver profiles, optimal regeneration is complex to obtain because the profiles are not favorable to it. The solution proposed by the present invention is purely software and does not involve the addition of elements in the exhaust line using sensors already present in the motor vehicle or functions already controlled by the control unit command of the engine or the particulate filter supervisor.

The invention is in no way limited to the embodiments described and illustrated which have been given only by way of examples.

I

Claims (10)

1. Method for assisting in the regeneration of a particle filter (3) of an exhaust line (1) of an internal combustion engine (2) of a motor vehicle, the filter (3) particles which must undergo regular regeneration, characterized in that conductor profiles are defined and their influence is estimated to be more or less favorable for carrying out a regeneration and that, for the conductor profiles least favorable for holding during regeneration, the particulate filter (3) is subjected to additional heating as long as the temperature of the particulate filter (3) is less than or equal to a temperature threshold value. 2. Method according to claim 1, in which the conductor profiles being the least favorable are, taken individually or in combination, conductor profiles mainly carrying out short journeys not permitting completion of a regeneration during a short journey, driver profiles mainly driving in cities and driver profiles starting under cold climatic conditions. 3. Method according to claim 2, in which a learning of the driver profiles is done according to at least one of the following parameters, taken individually or in combination: a predetermined number of days passed, a total distance traveled, an average driving speed during the predetermined number of days elapsed or the distance traveled, an association of a number of distances traveled between two starts less than a first lower mileage threshold and a number of distances traveled between two starts greater than a second upper mileage threshold , an outside temperature and a temperature of the internal combustion engine (2) at start-up estimated according to a temperature of the engine coolant (2). 4. The method of claim 2 or 3, wherein it is also taken into account the current driving conditions or the amount of particles retained in the particle filter (3). 5. Method according to any one of claims 2 to 4, in which, for a particle filter (3) retaining an amount of particles close to a predetermined maximum limit retained in the particle filter (3), for conductors starting under cold climatic conditions or for conductors mainly making short journeys which do not allow a regeneration to be completed during a short journey with, in the latter two cases, a calibratable value of quantity of particles in the filter (3) to particles at least greater than one tenth of the predetermined maximum limit retained in the particle filter (3), this calibratable value depending on an average distance between two starts, according to the associated conductor profile, the auxiliary heating of the filter (3) particle is activated from start up. 6. Method according to any one of the preceding claims, in which the auxiliary heating is an electric heating. 7. An assembly of a particle filter (3) in an exhaust line (1) of an internal combustion engine (2) of a motor vehicle and of its supervisor (7) managing regeneration, characterized in that that it implements a method according to any one of the preceding claims, the supervisor (7) comprising or cooperating with means for memorizing and determining driver profiles, means for qualifying a driver profile as being critical for regenerating a particulate filter (3) and means for actuating at least one heating element (8) to supplement the particulate filter (3) when a conductor profile is qualified as a critical profile for regeneration. 8. The assembly of claim 7, wherein said at least one heating element (8) is at least one electric heating element (8) heating a ceramic contour of the particle filter (3) or heating an interior of the ceramic of the particle filter (3). 9. Motor vehicle provided with an internal combustion engine (2) equipped with an exhaust line (1) comprising a particle filter (3), the engine (2) being controlled by a control unit command (6 ), the particle filter (3) being associated with a supervisor (7) forming an assembly, characterized in that the assembly conforms to any one of claims 7 or 8, the supervisor (7) cooperating with the unit control command (6) to manage regeneration of the particulate filter (3). 10. Motor vehicle according to claim 9, wherein said at least one auxiliary heating element (8) is electric and is supplied directly by an alternator driven by a crankshaft of the internal combustion engine (2) or by a rechargeable battery. by the alternator. 1/1