FR2863005A1 - METHOD FOR CONTROLLING THE REGENERATION OF AN INTEGRATED TRAP IN THE EXHAUST LINE OF AN INTERNAL COMBUSTION ENGINE AND SYSTEM FOR ITS IMPLEMENTATION - Google Patents

Abstract

The method involves periodically regenerating a particle filter (7) by eliminating polluting substances from the filter, using four electrically driven injectors (9-12). The moment of regeneration is chosen based on prior operating conditions of a vehicle, e.g. number of kilometers traveled by the vehicle, from the last regeneration and estimation of future operating conditions provided by a navigation system (30).

Description

2863005 1

  METHOD FOR CONTROLLING THE REGENERATION OF AN INTEGRATED TRAP IN THE EXHAUST LINE OF AN ENGINE

  INTERNAL COMBUSTION AND SYSTEM FOR ITS IMPLEMENTATION

ARTWORK.

  The present invention relates to a method for controlling the regeneration of a trap for polluting substances emitted by an internal combustion engine equipping a motor vehicle or road. The present invention also relates to a system for implementing this method.

  It is known that the constant concern of car or truck manufacturers is the reduction of the polluting emissions of internal combustion engines.

  Different systems have already been developed to reduce the level of these polluting emissions. Among the most efficient systems are the trapping systems housed in the exhaust lines of the engines. Such traps have the function of retaining specific polluting chemical compounds and thus avoiding their discharge to the atmosphere. Diesel particulate filters or NOx traps (nitrogen oxides) are particularly known.

  Since the pollutant storage capacity of such traps is necessarily limited, their regenerations should be periodically scheduled. However, and despite the many solutions already developed by one and the other, the management of the regeneration of a trap still generates difficulties.

  Indeed, consider for example a particle filter. One solution for regenerating such a particulate filter is to operate the combustion of the particles trapped therein. To cause the combustion of the particles, it is necessary to bring them to temperatures of at least 550 ° C. Given the usual conditions of vehicle circulation, the exhaust gases of diesel engines naturally reach these temperatures. Thus, in urban traffic, the exhaust gas temperatures generally vary between 150 and 250 C. Therefore, without being able to rely on a natural regeneration of the filter, it is necessary to increase the temperature of the exhaust gases to burn the exhaust gases. particles contained in the filter and therefore have the appropriate means for it. The temperature increase of the exhaust gases is carried out in the engines and / or at the level of the particulate filters. The increase in the temperature of the exhaust gases in the engines is, for example, obtained by the afterburner of a certain amount of fuel injected late in the cycle. The increase of the temperature of the exhaust gases in the particulate filters is, for example, obtained by electric heating means located upstream or inside the filters.

  This induced increase in the temperature of the exhaust gas to burn the particles is periodically effected according to predetermined strategies. The regeneration of the heating means can be performed simply every X kilometers, or even when a predetermined quantity of particles has been trapped in the filter or even when the difference between the pressures of the downstream gases and the pressure upstream of the filter exceeds a predetermined threshold value ...

  Whatever the technique used to cause the temperature rise of the exhaust gas, the regeneration operation causes an overconsumption of fuel compared to the normal operation of the engine, whether directly, by the 2863005 3 afterburner of a a certain quantity of fuel, or indirectly, by consuming a certain quantity of fuel to supply the engine with the additional power necessary for producing the energy consumed by the means of assisting the regeneration of the electric heating or other type .

  Furthermore, the presence of a trap filtering the exhaust gas causes a pressure drop in the exhaust line, more or less pressure drop depending on the amount of trapped particles. This back pressure generates an increase in the engine load and therefore an increase in the fuel consumption of the engine.

  Thus, the use of a trap in the exhaust line to stop the polluting substances before their discharge to the atmosphere represents a cost in terms of fuel consumption, cost which should therefore be limited.

  The present invention therefore proposes to optimize the operation of the traps and in particular the timing of the regenerations and this, to limit overconsumption of motors related to these traps.

  The control method according to the invention relates to the regeneration of a trap for pollutants emitted by an internal combustion engine equipping a motor vehicle or road. This control method is intended to control the operation of means of periodic regeneration of the trap by eliminating the substances that are trapped therein.

  According to the invention, the control method is characterized in that the moment of triggering of the regeneration is chosen so as to limit the duration of the regeneration and to limit the overconsumption of said motor generated by the trap, the choice of the moment being based on the knowledge of the past operating conditions of said vehicle which have occurred since the last regeneration and on the estimation of the future operating conditions of said vehicle, these future conditions being provided by means of predictions of the operation of the vehicle.

  According to another characteristic of the method which is the subject of the present invention, the moment of regeneration is defined as a number of kilometers to be traveled by the vehicle as from the last regeneration.

  According to another characteristic of the method that is the subject of the present invention, the means for predicting the future operation of the vehicle comprise a navigation system and / or radio-traffic type systems able to determine the path of said vehicle and / or the traffic conditions. to come up.

  According to another characteristic of the method that is the subject of the present invention, said future operating conditions are deduced from the operating conditions previously encountered by said vehicle.

  According to another characteristic of the method that is the subject of the present invention, the determination of the moment of the regeneration consists in searching for a first optimal theoretical moment of regeneration which minimizes the overconsumption in fuel of the engine, then to look for on both sides of said first moment. within a predetermined range, a moment that allows rapid regeneration, the latter being the moment chosen to trigger the effective regeneration of the trap.

  According to another characteristic of the method that is the subject of the present invention, the operating conditions of the vehicle are modeled as a finite number of rolling type, for each type of rolling corresponding to the operating ranges defined by the values taken by appropriate characteristic quantities such as vehicle speed and engine torque.

  According to another characteristic of the method that is the subject of the present invention, each type of rolling is associated with a regeneration distance that optimizes overconsumption in fuel and a corresponding regeneration time.

  According to another characteristic of the method which is the subject of the present invention, the past and future operation of the vehicle is found expressed in the form of a succession of sections, each section being defined by a given type of rolling and a characteristic data item such as its length. in number of kilometers. According to another characteristic of the method which is the subject of the present invention, the optimum theoretical moment of regeneration is determined by the generic formula: Ei (Di / DistOptRegeRi) = 1 where Di is the distance traveled inside the ith section and where DistOptRegeRi is the optimum theoretical regeneration distance for the rolling type Ri corresponding to the ith section. According to another characteristic of the method which is the subject of the present invention, the length of the interval considered around the theoretical optimum regeneration moment for determining the actual regeneration time is less than or equal to substantially 30% of the corresponding distance at the moment. optimal theoretical regeneration.

  The invention will be better understood on reading the description which will follow, given solely by way of example and with reference to the appended drawings, in which: FIG. 1 is a block diagram illustrating a motor vehicle diesel engine, and the various members associated therewith, FIG. 2 is a diagram showing the filter supervision system according to the invention; FIGS. 3 and FIG. 4 detail the sub-modules of the supervision system, FIG. 5 schematically illustrates the method of choosing the regeneration time implemented by the supervision system according to the invention.

  It has in fact shown in Figure 1, a diesel engine of the type equipping a motor vehicle, engine designated by the general reference 1, the diesel engine being equipped with a particulate filter 7.

  It is of course that the present invention is not limited to this type of engine or to this application only to motor vehicles or even to this type of trap but concerns all internal combustion engines regardless of their type and whatever their applications, insofar as the operation of these motors causes the emission of polluting chemical compounds which require for their treatment their entrapment in an appropriate trap and the periodic regeneration of the latter.

  The diesel engine 1 is associated with inlet air intake means thereof, which are designated by the general reference 2. At the output, this engine is associated with an exhaust line which is designated by the reference general 3.

  Motor exhaust gas recirculation means at the inlet thereof are also provided and are designated by the general reference 4.

  These means are then interposed for example between the output of the engine and the air intake means 2 therein.

  The exhaust line may also be associated with a turbocharger designated by the general reference 5 and more particularly to the turbine portion thereof, in a conventional manner.

  Finally, the exhaust line comprises an oxidation catalyst designated by the general reference 6, disposed upstream of a particulate filter designated by the general reference 7, disposed in the exhaust line.

  The engine is also associated with a fuel system for example common fuel cylinders thereof. This system is designated by the general reference 8 in this figure and comprises for example electrically operated high pressure injectors associated with these cylinders.

  Of course, other high pressure supply systems such as pump injectors can be envisaged. In the exemplary embodiment shown, the engine is a four-cylinder engine and therefore comprises four electrically operated injectors, respectively 9,10,11 and 12.

  These different injectors are associated for example with a common fuel supply ramp designated by the general reference 13 and connected to fuel supply means designated by the general reference 14, comprising for example a high pressure pump.

  These supply means are connected to a fuel tank designated by the general reference 15 and for example to means for adding to this fuel an additive intended to be deposited on the particulate filter to lower the combustion temperature of the fuel. particles trapped in it.

  In fact, this additive may for example be contained in an auxiliary tank designated by the general reference 16 associated with the fuel tank 15 to allow the injection of a certain amount of this additive into the fuel.

  Other means for lowering this temperature may also be used such as a catalyzed particulate filter.

  Finally, this motor and the various components which have just been described are also associated with means for controlling their operation designated by the general reference 17 in this figure, comprising, for example, a suitable computer 18 associated with storage means. information 19, and connected in 2863005 9 input to different means of acquisition of information relating to different operating parameters of the engine and these bodies, the calculator then being adapted to control the operation of the admission means, means of recycling, the turbocharger and / or the power system to control the operation of the engine and in particular the torque generated by it according to the driving conditions of the vehicle in a conventional manner.

  For example, this calculator is connected to a differential pressure sensor 20 at the terminals of the catalyst and of the particle filter, respectively 6 and 7, at one or more temperature sensors 21, 22 and 23, respectively upstream of the catalyst, between this catalyst and the particulate filter and downstream of the particulate filter in the exhaust line.

  The pressure sensor 20 can also be connected to the terminals of the filter alone.

  The computer may also receive oxygen content information of the exhaust gas from a Lambda probe designated by the general reference 24 in this figure, integrated into the exhaust line.

  At output, this computer is adapted to control the air intake means, the exhaust gas recycling means, the turbocharger, the means for adding fuel to the additive, the fuel supply means of the common rail and the various injectors associated with the engine cylinders.

  In particular, this calculator is adapted to trigger a regeneration phase of the particle filter by combustion of the particles trapped therein by engaging a phase of multiple injections of fuel into the cylinders of the engine during their expansion phase.

  The particles emitted by the engine during its operation are indeed trapped in the particulate filter. It is then necessary to regenerate it regularly by combustion of these particles.

  The control means 17 are also associated with means for determining, the activation state of the oxidation catalyst 6 formed by the computer 18 thereof, for, during the regeneration of the filter, to adapt continuously the conditions of unfolding the phase of multiple injections of fuel in the engine cylinders to take into account the activation state of the catalyst.

  This is achieved by controlling the phasing and / or amount of fuel injected during multiple injections to continuously adjust the amount of hydrocarbons produced during this phase by the engine, at the catalyst activity level and optimize the operation of the engine. this, by piloting the fuel system 8.

  Continuous monitoring of the activity level of the catalyst therefore makes it possible to continuously control the phasing and / or the quantity of fuel injected to continuously optimize the operation of the catalyst and therefore the temperature within this catalyst, avoiding any degradation of that catalyst. of particulate filter or engine and any production of fumes or odors.

  The activation state of the catalyst 6 can be determined by the computer 18 for example from the information supplied by the temperature sensors 21 at the catalyst inlet and 22 at the outlet thereof, in a conventional manner.

  Preferably, the computer 18 is associated with an integrated numerical modeling of the catalyst to know its state of activity from the information provided by the sensors.

  Of course, other means can be used, for example means for analyzing the chemical composition of the exhaust gas at the inlet and outlet of this catalyst.

  As indicated above, it is the computer 18 which triggers the regeneration of the particulate filter. This regeneration is performed by post fuel injection. This post-injected fuel will ignite late and burn in the exhaust line and thus cause the filter right the combustion of soot. The time required to operate the combustion of soot trapped in the filter and therefore the amount of fuel to be post-injected is directly dependent on the operating point of the engine and in particular the temperature of the exhaust gas.

  Indeed, it has been observed that the effectiveness of this post injection can be zero or almost in certain circumstances and especially when the exhaust gas is too cold or too low flow. So that for particular points of engine operation, no regeneration can take place and this, whatever the amount of fuel post-injected.

  It follows therefore that depending on the point of operation considered, the regeneration operation is, can not be triggered either, can be triggered but with a greater or lesser fuel consumption.

  Moreover, the presence of such a particulate filter in the engine exhaust line creates a more or less significant loss of charge depending on its degree of filling. This pressure drop and therefore the resulting back pressure generates overconsumption of the engine, overconsumption which is then directly a function of the level of filling of the filter.

  The presence of a particulate filter is therefore in itself a significant potential source of overconsumption of the engine.

  The present invention therefore proposes to control the operation of the filter and in particular the regeneration phase of the particulate filter not taking into account the single degree of filling of the filter as in the prior art, but mainly taking into account the overconsumption the engine generated by the operation of the filter and this, to minimize the importance of such overconsumption.

  The present invention proposes more precisely to find an optimum between too frequent regenerations which would induce a global overconsumption of the high engine linked to the numerous postinjections and regenerations too spaced which would also induce a global overconsumption of the high engine because of strong counterpressions to the exhaust.

  The optimization of the regeneration strategy therefore consists in choosing at best the triggering of the regeneration phases.

  Such an optimization is achieved by using the control method described hereinafter implemented by the following system called supervisor consisting of a software program executed by the engine control computer 18. The supervisor receives via the computer 18 the information relating to the conditions of use of the vehicle and engine operation such as its speed, the position of the accelerator pedal, the engine rotation speed, etc. These different input information of the program are analyzed and at the output, the supervisor triggers and controls the regeneration phases of the filter.

  According to Figure 2, the supervisor can consist mainly of three modules. A first driving module called NR, for Necessity to Regenerate, more particularly has the function of knowing the level of soot load of the filter and its consequences on the operation of the vehicle in terms of fuel consumption.

  A second module called CR, for Regenerate Capacity, evaluates the efficiency of a regeneration request under current or future engine operating conditions.

  A third module called D, to Decide, exploits the information received from the first two modules and triggers the regeneration phases by minimizing the impact on the engine consumption and in critical cases ensures the operational safety of the filter and the engine.

  As illustrated in FIG. 3, the first module NR is itself composed of two submodules. The first submodule NR_MCF provides the level of charge of the filter mass of carbonaceous particles only. It is a question of respecting the specifications of the 2863005 14 supplier of the ceramic forming the body of the filter and in particular the maximum permissible load of carbon in order not to damage the filter during critical regenerations that is to say low flow and mass high soot. The indicator at the output of this submodule must characterize different states of charge ranging from the empty state to the maximum charge state.

  The second submodule of the NR module is the NR MS submodule which provides the optimum regeneration distance, evaluated from the last regeneration to date. The optimal regeneration distance will vary regularly depending on the driving conditions encountered by the vehicle. The indicator at the output of the module must characterize the optimal regeneration distance of the filter and the situation of the vehicle with respect to this optimum.

  As illustrated in FIG. 4, the second module CR is also composed of two submodules. The first submodule CR_MCT characterizes the regeneration capacity under the current conditions of use of the engine and one of the output indicators of the module is the success rate of a possible regeneration performed under the present conditions and the second sub-module CR_MLT characterizes the regeneration capacity to come and the output indicator is the probability of meeting more favorable conditions for regeneration than the present conditions.

  To simplify the processing times and the operation of the supervisor, the areas of use of the vehicle and the engine have been segmented into a predetermined number N of rolling types Ri (with i ranging from 1 to N). According to one embodiment of the invention illustrated in FIG. 5, the operating range of the engine has been decomposed into five types of rolling and the parameters 2863005 15 selected to characterize these types are the engine torque and the vehicle displacement speed.

  This number of rolling types and these parameters are not, however, limiting of the invention, N being able to be more or less important, in particular according to the microprocessor calculation capacities equipping the computer 18, likewise the parameters used to characterize the types of operation. can be more or less numerous, one could for example take into account the engine speed, the temperature of the coolant, etc. Each type of rolling Ri is thus defined to correspond to a substantially homogeneous operation vis-à-vis the particulate filter.

  For each of the rolling types Ri, the optimum distance DistOptRegeRj regeneration minimizing the overconsumption associated with the regeneration phase filter is then determined (assuming that the engine operates in steady state steady state within this type of rolling) . This distance is defined from the end of the last regeneration performed on the filter.

  For the type or types of rolling where a regeneration is not possible given the operating conditions that are encountered, then a distance DistOptRege is determined relative to the filling of the filter.

  For each of the rolling types Ri, the regeneration time of the filter DureeRegeOptRj is also determined when it is initiated at the optimum distance of regeneration DistOptRegeRJ. Of course, for the type or types of rolling where a regeneration is not possible given the operating conditions that are encountered this time is not calculated.

  These different values are put in one or more maps stored by the engine control system.

  The submodule CR_MCT has a particular function to characterize the operation of the engine and the vehicle and to identify what type of rolling Ri it is. Based on the information received from the different sensors, the CR_MCT module periodically calculates the value of the type of running where the motor is located, this raw value is then filtered to eliminate the transients. This results in the information according to which the vehicle is at the present moment in a given type of running run Ri. The CR_MCT module also calculates the distance traveled in each type of taxi.

  The module CR_MCT is adapted to identify the type of rolling 20, for example by calculating an instantaneous criterion for rolling the vehicle according to the relation: Cr inst = V (1 + k C) With Cr inst: Instantaneous driving criterion V: Vehicle speed C: Motor torque K: Correction factor.

  This criterion of instantaneous rolling is then smoothed and compared by the computer to predetermined thresholds corresponding to the different types of rolling to determine the type of current running.

  Of course, other alternative embodiments can be envisaged, for example by modifying the parameters taken into account for calculating the instantaneous criterion.

  The types of rolling thus determined are stored and counted from the last regeneration observed in order to constitute a history of the types of driving followed by the vehicle. The operation of the vehicle and the engine is thus represented in the form of a succession of road sections, each section being characterized by a length in number of kilometers and a type of running. Of course other sizes could be taken into account to characterize a section like the driving time.

  We note, for example, that from the end of the last regeneration, the vehicle has traveled 10 km in R4 type of taxiing, then 45 km of traffic type R1 rolling, then 10km type R2 taxiing, then again 20km in type R1, etc. Each change of rolling type defining a new section.

  This history since the last regeneration can be stored informally in the form of a vector [(Di, Ri)], i ranging from 1 to m, with M number of typical operating running changes recorded since the last regeneration to the present moment, Ri representing the type of rolling encountered during the ith section and Pi representing the length in kilometers of section.

  Of course, M, which is the number of sections successively encountered by the vehicle and the engine since the last regeneration up to the present moment, regularly increases as the vehicle 2863005 18 is used up to moment of the new regeneration which then resets the counters. The sub-module CR_MLT has more particularly its function of predictively determining the next sections, that is to say those to be encountered during the present journey of the vehicle or future trips.

  This sub-module CR_MLT uses the results of the submodule CR_MCT it deals with statistics and / or specific information provided by a navigation system onboard the vehicle.

  Indeed, based on the criterion of instantaneous running, the computer 18 is adapted to construct a history of the conditions of use of the vehicle and to trigger the storage thereof in the means 19.

  This history makes it possible to calculate the probability of meeting more favorable conditions of use of the vehicle than the current conditions of use.

  This statistical information on the conditions of use of the vehicle gives an indication as to whether or not to postpone the initiation of the regeneration. A favorable statistical indication authorizes a postponement of this trigger in the case where short-term conditions are not favorable.

  A navigation system 30 is for example of the type able to provide a route after entering the destination or when this destination is known elsewhere and to guide the motorist along this route using for example the 2863005 19 GPS technology . Such a device, specific or integrated with a radio device, may also be able to receive information on road traffic and traffic restrictions in order to refine its guidance. This navigation system is therefore adapted to communicate to the engine control information on the nature of the path and the traffic conditions to be transcribed into types of operation running of the engine.

  From these data, the CR_MLT module is able to predict on a predetermined horizon, the conditions of vehicle circulation and engine operation. It is then able to discretize this horizon in the form of a succession of elementary sections Tk each corresponding to a given type of rolling of the vehicle.

  This discretization can, for example, be expressed in the form of the following series of sections (taking as a reference the current position of the vehicle): section TM + 1: over 10km circulation in rolling type R1, section TM + 2: on 25km traffic type R3, TM + 2: 50km type R5, TM + 4: again 5 km in type R1 rolling, etc. This can be represented by a vector formed by couples [(Rk, Dk)], k ranging from M + 1 to P, where P represents the total number of sections considered, Rk represents the type of rolling type corresponding to the kth section and Dk representing the length in kilometers of this kth section.

  Of course, P, which is the number of sections to be met successively by the engine for a given route horizon, decreases steadily as the vehicle is used and as the distance is approaching. point of arrival taken into account for the period in question.

  From the information relating to the past sections [(Ri, Di)] and the future sections [(Rk, Dk)], the submodule NR_MS is able to determine an optimal theoretical distance of regeneration by: (1) DistOptRegeTh = Ei Di + Ek Dk with i ranging from 1 to m, and k from M + 1 to M + Q.

  Q being defined by the appropriate formula by: (2) Ei (Di / DistOptRegeRi) + Ej (Dk / DistOptRegeRk) = 1 is again (3) Ej (Dj / DistOptRegeRj) = 1 with j ranging from 1 to M + Q is obviously that for the last stretch of rank M + Q, the distance taken into account is not necessarily the total distance DM + Q but the appropriate fraction DM + Q or we should consider that the triggering of a regeneration starts a new section.

  This calculation of the theoretical optimal distance DistOptRegeTh having been accomplished,. then proceeds to the calculation of the actual optimal distance DistOptRege at which regeneration will be triggered.

  To do this, we isolate a confidence interval of the type [X% x 25 DistOptRegeTh, Y% x DistOptRegeTh] with X less than 100% and Y greater than 100%, for example X is taken as equal to 85% and Y to 110 %.

  We then identify all the sections Tk which are included, for all or part, within this interval. Given the length of the gap it is a relatively small number of sections centered around the Q section that are thus selected.

  2863005 21 Consider for example that they are sections TM + Q_R to TM + Q + s.

  We then consider each of the beginning of these R + S + 1 sections as the beginning of the regeneration and then calculate the time required for regeneration. If a section is too short to accommodate all the regeneration, the regeneration continues on the following section (s). If a section taken into account in a regeneration time calculation prohibits all regeneration (temperature or flow rate too low) then the calculation stops and a predetermined value is counted.

  The time obtained Ti is thus recorded for each of the sections.

  We then start a new iteration on the different sections selected by considering this time the end of each section as the end of the regeneration and then calculates the time back to regenerate. If a section is too short to accommodate all the regeneration, the regeneration continues on the previous section (s). If a section taken into account in a regeneration time calculation prohibits the regeneration (temperature or flow rate too low) then the calculation stops and no predetermined value is counted.

  The time Tf obtained for each section is recorded.

  The lowest time is then determined among the different calculated times, and the optimum regeneration distance is then determined to be that corresponding to the moment of initiation of the regeneration having caused this weakest time. In the case of a tie between two beats, it is the one that has the nearest beginning or end time of the optimal distance of the theoretical regeneration 2863005 22 that will be preferred and the optimum optimum regeneration distance will be defined from this. latest.

  Of course, as the kilometers traveled by the vehicle, the share in the calculation of the optimum regeneration distance of the past sections increases and the share of predicted sections decreases. This evolution is therefore accompanied by a corresponding modification of the value of this optimum regeneration distance. However, this value is frozen as soon as the vehicle enters the aforementioned confidence interval.

  Moreover, if during the regeneration trigger when the optimum regeneration distance is reached, the type of running encountered does not allow or badly the regeneration, then the regeneration is pushed back until the vehicle is in a new type. rolling more conducive to the regeneration of the filter.

  It is conceivable then, that thanks to such a structure, one optimizes the initiation of the regeneration.

Claims (2)

  [1] A method for controlling the regeneration of a trap (7) for polluting substances emitted by an internal combustion engine fitted to a motor vehicle or road vehicle, comprising controlled means (9, 10, 11, 12) for periodically regenerating said trap (7) by eliminating the substances trapped therein, characterized in that the moment of the regeneration is chosen so as to limit the duration of the regeneration and to limit the overconsumption of said engine generated by said trap, the choice of said moment being based on the knowledge of the past operating conditions of said vehicle which have occurred since the last regeneration and on the estimation of the future operating conditions of said vehicle, these future conditions being provided by prediction means (30) of the operation of the vehicle.   [2] Regeneration method according to claim 1, characterized in that the moment of regeneration is defined in the form of a number of kilometers to be traveled by said vehicle from the last regeneration.   [3] Regeneration method according to any one of claim 1 or 2, characterized in that said means for predicting the future operation of said vehicle comprises a navigation system (30) and / or capable radio-traffic type systems determining the path of said vehicle and / or the traffic conditions to come.   [4] Regeneration method according to any one of claim 1 or 2, characterized in that said future conditions of operation are deduced from the operating conditions previously encountered by said vehicle.   [5] Regeneration method according to any one of claims 1 to 4, characterized in that said determination of said regeneration time is to seek a first optimal theoretical moment of regeneration which minimizes overconsumption of engine fuel, then to seek on either side of said first moment, within a predetermined interval, a second regeneration moment which allows rapid regeneration, said second moment then being the moment chosen to operate the effective regeneration of the trap.   [6] Regeneration method according to claim 5, characterized in that said operating conditions of said vehicle are modeled from a finite number of rolling type, each corresponding rolling type of operating ranges defined by the values taken by suitable quantities such as vehicle speed and engine torque.   [7] Regeneration method according to claim 6, characterized in that each type of rolling is associated a regeneration distance optimizing overconsumption fuel and a corresponding regeneration time.   [8] Regeneration method according to claim 6, characterized in that said past and future operation of the vehicle is found expressed in the form of a succession of sections, each section being defined by a given type of rolling and a characteristic data such as than its length in number of kilometers.   A regeneration method according to claim 8, characterized in that said first optimum theoretical moment of regeneration is determined by the generic formula: Ei (Di / DistOptRegexi) = 1 where Di is the distance traveled within the section I and where DistOptRegeuii is the theoretical optimal regeneration distance for the type of rolling corresponding to the ith section.   [10] Regeneration method according to claim 5, characterized in that the length of said interval around the optimum theoretical moment of regeneration is less than or equal to substantially 30% of the distance corresponding to the optimum theoretical moment of regeneration.