FR3006372A1 - METHOD OF ESTIMATING POLLUTING EMISSIONS OF INTERNAL COMBUSTION ENGINE AND ASSOCIATED METHOD OF CONTROLLING ENGINE - Google Patents

Abstract

The invention proposes a method for managing an internal combustion engine (1), in which at least one pollutant emission value of a polluting species is estimated using engine parameters other than the pressure of the engines. gas in the cylinders (6) of the engine (1), at least one emission value being calculated as the product of a first function affine fuel consumption (Qcarb), a second function affine of the advance (φ) at the ignition of the engine, a third function refines the temperature (T) of the engine coolant, and a negative exponential term of a power of the wealth (R) of the engine; combustion mixture in the cylinders (6) of the engine.

Description

The invention relates to the control of polluting emissions of an internal combustion engine. The pollutant emission level of the engine depends in particular on the combustion conditions of the combustion mixture in the engine cylinders. It therefore depends on the composition of the mixture, but also on the temperature and pressure conditions at which the combustion takes place in the cylinders. One of the known variables for evaluating the level of production of various polluting emissions is the pressure developed in the cylinders at the time of combustion. The knowledge of this pressure, however, requires the use of specific sensors, which leads to an additional cost of the engine. The sensor can also be easily damaged by the pressures and temperatures used. The aim of the invention is to propose methods for evaluating the emissions of one or more polluting species, which use sensors and estimators other than pressure sensors in the cylinders, the sensors used being in general already present on the engine for other engine control purposes, for example to optimize engine fuel consumption.

The invention also aims to propose inexpensive estimation methods in computing capabilities, and methods that require, to be calibrated, a reduced number of bench tests. The invention also aims to allow a reduction of the pollutant emissions of the engine, by introducing a consideration of the estimated values of polluting emissions, when controlling the engine to obtain the desired engine torque by the driver of the vehicle .

To this end, the invention proposes an internal combustion engine, the engine comprising a pollutant emission estimating device. Preferably, the engine has no pressure sensor in any cylinder of the engine, or at least the pollutant estimator does not use pressure values obtained by sensor measurement in one or more cylinders of the engine. The estimation device is configured to calculate a first pollutant emission value by taking into account the rotational speed of the engine, a measured temperature of coolant circulating in the engine, a fuel consumption of the engine, an estimated indicative value. the richness of the gases entering the engine cylinders, and a level of advance ignition engine. The richness of the gases can be calculated in different ways according to the embodiments. According to a first embodiment, the richness can be calculated from a flow of fresh air entering the engine, and the fuel consumption of the engine. The fresh air flow can itself be measured by a flow meter, or can be estimated by means of a flow map which is a function, in particular, of the engine rotation speed and a gas pressure measured in the engine. intake manifold. The value extracted from the flow map can be multiplied by a measured pressure in the engine intake manifold, and can be divided by a temperature measured in the engine intake manifold. The cartography can also take into account instructions for controlling intake valves and gas exhaust from the engine cylinders. According to another embodiment, the richness of the gases entering the cylinders of the engine can be estimated by taking into account the mass actually trapped in the combustion chamber of the cylinders. It can then typically be calculated by reading a first value in a fill map, and a second value in a trapping map, and multiplying these two values by a constant coefficient and by a measured gas pressure in the intake manifold. of the engine and dividing the result by a measured gas temperature in the engine intake manifold.

In the case where the engine is equipped with a phase shift system of the openings of the intake and exhaust valves of the cylinders, the filling mapping and trapping mapping can take into account, in addition to the engine speed and the pressure of the engines. gas in the intake manifold, intake valve control instructions and gas exhaust of the engine cylinders. According to a first embodiment, the estimation device is configured to calculate a first pollutant emission value as the product of a first affine function of the fuel consumption, a second function affine of the advance of the fuel. ignition, a third function refines the coolant temperature, and a negative exponential term of a power of the richness of gas entering the cylinders. Advantageously, the first emission value is used to estimate the emissions of nitrogen oxides from the engine. By negative exponential term we mean a term where the value under the exponential is of negative sign. Preferably, the negative term under the exponential function is proportional to a power function of a difference between the richness of gas entering the engine and a threshold richness. According to a preferred embodiment, the power function is a power equal to two. According to a second embodiment which can be combined with the above, the estimation device is configured to calculate a second emission value, as a product of an affine function of the coolant temperature by the fuel consumption. of the engine, and by a third function refines the richness of the gases entering the cylinders of the engine. Advantageously, the second emission value is used to estimate the carbon monoxide emissions of the engine. Below a threshold richness, the estimation device can be configured to replace the third affine function of the richness of the gases entering the cylinders of the engine by a constant value.

According to a third embodiment which can be combined with the two previous ones, the estimation device is furthermore connected to a pressure sensor in an intake manifold of the engine and to a gas temperature sensor in the intake manifold. the engine, and means for estimating the rotational speed of the engine and a means for estimating the air flow entering the engine. The pollutant estimating device is then configured to calculate a third pollutant value, such as a product of an affine function of the ignition timing, by an affine function of the coolant temperature. multiplied by a first polynomial of the second degree, which is a function of the inverse of the speed of rotation of the motor, by a second polynomial of the second degree, which is a function of richness, and by a third polynomial of the second degree according to a reduced variable. The reduced variable is proportional to the air flow entering the engine and the temperature of the gases in the intake manifold, and inversely proportional to the gas pressure in the intake manifold of the engine. Advantageously, the third emission value is used to estimate emissions of incompletely burned hydrocarbons. According to an advantageous embodiment, the motor may further comprise a regulator configured to take into account a signal of an accelerator pedal. The controller is configured to develop from this signal a position setpoint of an actuator of the engine, by weighting the position setpoint with a value mapped according to at least one polluting emission value calculated by the estimator of the engine. polluting emissions. According to an advantageous embodiment, the engine comprises a first mapping giving a first multiplying coefficient function of one or more pollutant values calculated by the pollutant estimator, and comprises a second mapping making it possible to read a second multiplier coefficient depending on the pedal signal and the motor rotation speed. The regulator is then configured to apply the product of the first and second coefficients to a setpoint deviation variable, the setpoint deviation variable translating a difference between a setpoint value calculated as a function of the pedal signal, and a variable measured -or a variable derived from measurements- on the engine. The invention also proposes a hybrid vehicle comprising an electric machine and comprising a motor as described above. The vehicle may comprise an energy management module configured to deliver an electric torque setpoint to be supplied by the electric machine and to deliver a desired value of thermal torque to be supplied by the internal combustion engine. The vehicle may furthermore comprise a moderator module configured to weight the desired value of thermal torque as a function of an estimated value of pollutant emissions, and to deliver a setpoint thermal torque for developing a position setpoint of an actuator of the internal combustion engine. According to a preferred embodiment, the moderator module also returns the target thermal torque to the energy management module, which accordingly adapts the electrical torque setpoint.

The invention also proposes an engine equipped with a polluting species trap (s) and an estimation device configured to calculate an instantaneous value of polluting emissions corresponding to the species to be trapped. The engine may include a trap monitor configured to determine the amount of pollutant species accumulated in the trap by integrating a value estimated by the estimator. The pollutant species trap may for example be a nitrogen oxide trap. According to a preferred embodiment, the trap monitor is configured to trigger a purge of the trap when the amount of polluting species in the trap reaches or exceeds a threshold, which may be a function of the driving conditions of the vehicle. Purge means elimination by oxidation or reduction of polluting species. In the case of the nitrogen oxide trap, the purge can be done by modifying the operating parameters of the engine so as to heat the trap and to send therein reducing chemical species. These purge methods are known, for example to reduce nitrogen oxides to nitrogen. The invention also applies to a method for managing an internal combustion engine, in which at least one emission value of a polluting species is estimated using engine parameters other than the gas pressure in the engine. the engine cylinders, at least one polluting emission value being calculated as the product of a first function affine of the fuel consumption, a second function affine of the ignition advance, a third function refining of the coolant temperature, and a negative exponential term of a power of the richness of the combustion mixture in the engine cylinders. Other objects, features and advantages of the invention will become apparent on reading the following description, given solely by way of nonlimiting example, and with reference to the appended drawings, in which: FIG. 1 is a diagrammatic representation of an internal combustion engine equipped with a pollutant emission estimator according to the invention, FIG. 2 is a diagrammatic representation of an internal combustion engine equipped with a nitric oxide trap as well as a pollutant emission estimating device according to the invention, FIG. 3 is a schematic representation of a hybrid thermal-electric motorisation system provided with a pollutant emission estimator according to the invention. As illustrated in FIG. 1, an internal combustion engine 1, for example a gasoline type engine, comprises combustion cylinders 6, of which there are four in number, and comprises an air supply circuit 30 extending from one engine to the other. fresh air inlet 3 to an exhaust outlet 31. The air enters through the fresh air inlet 3, passes through an air filter 4, which may or may not have a flow meter, then passes through a compressor 5a of a turbocharger 5, to arrive in an intake manifold 32 from which it can be admitted into the cylinders 6 of the engine 1. The gas circuit 30 continues downstream of the cylinders 6 by an exhaust manifold 39 which receives the burnt gases from the cylinders 6. The burnt gases then pass through a turbine 5b of the turbocharger 5, then eventually pass through a pollution control system 33, to be returned to the atmosphere by the exhaust outlet 31. The arrival of essence to each cylinder 6 from the re fuel tank 19 of the vehicle is controlled by an engine control unit 8 which determines the amount of gasoline 0, carb admitted into each cylinder at each "stroke" engine, that is to say for each engine cycle of the cylinder . The engine control unit 8 also determines an ignition advance cp which is the angle that remains to be traveled to the crankshaft before reaching the top dead center, at the moment when a spark is triggered in the corresponding cylinder. The amount of fuel each "stroke" or engine cycle, as well as the ignition advance cp, are sent to a pollutant estimator 10.

The pollutant estimator 10 is an electronic control unit further receiving a T value of "water temperature" of the engine as measured by a sensor 34 measuring the temperature of the coolant passing through the engine. The estimator 10 also receives a value of engine speed N, which can for example be expressed in revolutions per minute, and which is measured by a tachometer 35, placed for example in front of a toothed wheel integral with the crankshaft of the engine 1. The pollutant estimator 10 also receives a value R of richness of the oxidant mixture entering the cylinders of the engine. This wealth value can be delivered by a wealth estimator 2. The oxidizer mixture richness estimator 2 can in particular use the fuel flow 0, carb entering the cylinders of the engine at each stroke, and the air flow Qair entering the gas supply circuit 30. L 2 estimator Qcarb sent in each cylinder may, according to other embodiments, perform the estimation of wealth from other parameters, as detailed below. Qair airflow can be measured by a flowmeter, for example placed at the level of the air filter 4, or can be estimated for example by means of a cartography making it possible to determine the air flow rate according to the speed of rotation of the engine and the pressure of the gases in the intake manifold 32. The intake manifold 32 may be provided with a collector pressure sensor 9 and a gas temperature sensor 11 in the manifold. 'admission.

According to the variant embodiments and depending on the polluting species that it is desired to quantify, the pollutant estimator may also be connected so as to receive, for the purpose of calculating some of the polluting emissions, the Qair air flow rate. , the pressure of the gases 13,01 in the intake manifold, and the temperature of the gases T, 01 in the intake manifold. The Qair value can be delivered, instead of a flowmeter at the level of the filter 4, by an estimator of the incoming air flow, using for example the cartography mentioned above, as a function of the rotation speed of the engine and the pressure The pollutant estimator 10 delivers one or more values each representing a quantity of polluting species emitted per unit of time. FIG. 1 shows the transmission of a single pollutant emission value "Pollut", which is sent as an input value of a mapping 13. According to the variant embodiments, the Pollut value can represent a flow of nitrogen oxides "NO x", a flow rate of carbon oxides "CO", or a flow of unburned hydrocarbons "HC". The estimator 10 can also simultaneously deliver several values corresponding to several polluting emissions. This or these pollutant emission values may be used to adapt the regulation of the engine 1, as illustrated in FIG. 1. In the example illustrated in FIG. 1, where the pollutant emission value Pollut may for example correspond to a nitrogen oxide flow rate, Pollut emission level is used as the input value of the map 13, in which is read a multiplier Kpon which is then sent to a multiplier 16. The multiplier 16 receives on another input a second coefficient KNc which is read in a second map 14. The second map 14 has at least two inputs, whose rotation speed N of the engine 1 is a reference torque C, which is determined for example from the signal d an accelerating pedal 12. The setpoint torque C is also used by a setpoint boost pressure calculator 15 which is configured to calculate a supercharger pressure. setpoint Pcons obtain in the intake manifold 32 to obtain the motor 1 the torque C required. The map 14 can use as a second input value another value related to the torque, for example the reference supercharging pressure P - cons. The multiplier 16 delivers a Krégul control coefficient which is used by a regulator 18. The regulator 18 receives at the inlet a difference c between the pressure 13.01 of gas measured in the intake manifold 32, and the corresponding setpoint pressure P 0, delivered by the set-point pressure control computer 15. The regulator 18 converts this difference c into a correction value δ sent to a conversion unit 7. The regulator 18 may be of the proportional type, but may also be of proportional integral, proportional derivative or other type of regulator, of the PID type. . Other types of regulators may also be envisaged, involving non-multiplicative type corrections and / or involving clipping functions as a function of the received Krégul control coefficients. It is not departing from the scope of the invention if the combination of the coefficients from the maps 13 and 14 is other than by a simple multiplication. The coefficient resulting from the mapping 13 may, for example, impose a limit on the coefficient resulting from the mapping 14. The conversion unit 7 is configured to deliver a position command "u" enabling the geometry of the turbine 5b to be adapted in order to change the flow rate through the turbine. The value "u" may for example correspond to the blade positions of a variable geometry turbine 5b. The conversion unit 7 uses of course other values than the correction value δ to calculate the position "u" of the actuator of the turbine 5b. These values correspond to calculation methods known from the literature and may in particular comprise a gas temperature measured upstream of the turbine, a flow of gas passing through the turbine and a gas pressure downstream of the turbine. In general, the internal combustion engine 1 may comprise a pollutant estimator 10, the Pollut estimation of which is taken into account for the calculation of a Krégul regulation coefficient making it possible to calculate a position "u" of a actuator for modifying the combustion conditions of the engine 1, and in particular for changing the pressures established inside the gas circuit 30. In a first embodiment, the estimator 10 calculates a production of nitrogen - by cylinder stroke - using the richness R, the fuel flow 0, carb, the ignition advance cp, the water temperature T and the engine speed N, according to the equation (1 ): (R-R0) \ 2 NOX = K Equation (1) mgc (Qcarb ± Q0) (p ± Po) (T ± T0) exp With: Qcarb fuel flow mg / stroke: ignition advance (position crankshaft in degrees) T: engine coolant temperature (degrees Celsius) R: richness in the cyl indres (without dimensions) The values Qo, (po, To, Ro, s are engine-specific calibration parameters, which can be determined by bench tests for a particular engine model.

The value obtained NOXmgc is expressed for a crankshaft revolution. If we want to convert mass production per unit of time, we can use the conversion formula (valid for a four-stroke and four-cylinder engine): / 1 \ Ij NOXmgis = 2.NOXmgc - Equation (2) 60 N being the rotational speed of the engine in revolutions / minute. According to another embodiment which can be combined with the preceding one, the pollutant estimator calculates the carbon monoxide emissions COo, gc, according to a formula of the type: If R <R, e COmgc = H Qcarb - (T + T0) Equation (3) If R> ee CO ', gc = M (R + Ri) - Qat - (T ± TO) Equation (4) The values H, R1, M are engine-specific calibration parameters, which can be determined by bench tests for a particular engine model. The To value can be the same as above for the evaluation of the production of nitrogen oxides.

The value obtained comgc is expressed for a crankshaft revolution. If it is desired to convert the mass production per unit of time, the conversion formula can be used: C ° mg I s = 2-C ° mgc-60 Equation (5) N being the rotational speed of the engine in revolutions / minute.

According to a third embodiment which can be combined with the first and / or second embodiment, the pollutant estimator calculates the unburned hydrocarbon emissions HC mgc, according to a formula of the type. - R + p). (X2 + uX + HC gc = + + T o): Equation (6) d \ + + - - e r2 N Where T: engine coolant temperature (degrees Celsius) R: cylinder richness (without dimensions) N: the speed of rotation of the motor in revolutions / minute The value X is a reduced variable defined as follows: x = Q air * Tc01 _ 0 air mgc T col, 13Q N Pcoi Pcoi Equation (7) with Q air flow de air in kg / h Qair mgc air flow in mg / blow pressure in the manifold [Pa] Tc01: intake manifold temperature in [K] The values L, To, (pi, d, e, r, p, u, v are engine-specific calibration parameters that can be determined by bench tests for a particular engine model The To value can be the same as above, of course, equations (1), (3), (4) and (6) can be replaced by equivalent equations by different factorization of the calibration constants.The value obtained HCmgc is expressed for a turn of crankshaft. If it is desired to convert the mass production per unit of time, the conversion formula can be used: HCmg I s = 2.HCmgc - Equation (8) 6N0 j The value obtained HC mgc is expressed for a crankshaft revolution. If we want to convert the mass production per unit of time, we can use the conversion formula: Nj 5Equation (9) HCmg I s = 2.HCmgc - 60 Equations (1), (3), (4) can be replaced by equivalent equations, where for example the fuel flow is expressed in mg / s instead of being expressed in mg / stroke. The terms relating to the fuel flow 0, carb and Qo are then to be taken into account divided by the rotation speed N, and the calibration constants K, H, M are to be adapted, for example by dividing them by 30. In all the above calculations, the air richness R of the oxidant mixture in the cylinders can be evaluated in different ways. According to a first embodiment, it can be measured by a probe of the "lambda probe" type. The lambda probe is generally placed on the gas circuit 30, downstream of the cylinders and upstream of the possible pollution control system 33. It makes it possible to determine the oxygen richness of the exhaust gases and to deduce the composition therefrom. gases entering the cylinders. According to another embodiment, the richness R of the gases in the cylinders is calculated by taking into account the flow of air entering and the flow of fuel entering the cylinders. According to the simplest model, the richness R of the gases enclosed in the cylinders at the moment of combustion can be calculated by R = Qcarb / Qa * PCO Equation (10) With PCO = fuel comburivore power, PCO = 14.7 30 for gasoline for example. Qcarb and Qair are both expressed here per unit of time, or both "per shot".

It can be seen that the pollutant estimator 10, using equations (1) and (2) to estimate the production of nitrogen oxide, makes it possible to introduce an additional control factor when developing the setpoint "u" for the turbine 5b. It is thus possible, for example, during a rise in power of the engine required from the pedal 12, to moderate the rise in power of the engine 1 as a function of the nitrogen oxide emission values calculated by the estimator 10: it can for example make this increase in power more progressive, limit the instantaneous emissions, and if possible the overall emissions, of nitrogen oxide by the engine 1. The same type of limitation can be applied, independently or simultaneous, from carbon monoxide emission values calculated from equations (3), (4) and (5). The pollutant emission estimator 10 may, for example, deliver two separate values NOX ', gis and COmg / s giving instantaneous productions of these two pollutants. These values (or their values converted into mass / second) can be sent to two maps (not shown in FIG. 1) making it possible to read two correction coefficients that will multiply the KNC coefficient delivered by the map 14 according to the operating point of the engine. . A third correction may be added, depending on the amount of unburned hydrocarbons, also calculated by the pollutant estimator, and which may be read a third time in another map (not shown). to extract a dedicated correction coefficient. FIG. 2 illustrates another application of the pollutant calculation methods according to the invention. FIG. 2 shows a motor equipped with the same sensors as that of FIG. 1, the same sensors being designated by the same references. In Figure 2 however, the air filter 4 is not equipped with a flow meter. The incoming airflow Qair and the richness R must therefore be evaluated from the data of the other sensors. For this purpose, an air mass estimator 40 is used which passes through the intake valves of the cylinders. The estimator comprises a mapping 41 of filling, which gives a filling coefficient ih, as a function of the pressure Pcol measured in the intake manifold 32, the rotation speed N of the engine, and setpoints VVTa and VVTe for driving respectively the intake valves and the cylinder exhaust valves. These instructions may correspond for example to a position at a given moment, or to a phase shift with respect to the passage of the piston of the cylinder by its top dead center. The estimator 40 may further comprise a map 42 which gives a "trapping" coefficient according to the same four parameters. Thus, the estimator 40 reads in the map 41: 11, = f, (N, Pcoi, VVT ,, VVT Equation (11): filling coefficient and reads possibly in the mapping 42 ft (N, P ,,,, VVT ,, VVT,) laughs: trapping coefficient (mapped) An estimate of the air flow entering () air mgc can then be obtained by the following equation: 20Qalr Pcoi Equation (12) -mgc = r .0 287 T 01 v with Qair mgc: estimated air mass passing through the intake valves, in mg "per stroke" Cyl: maximum internal volume of a cylinder of the engine 25 ("displacement") And the air mass actually trapped in the cylinders and available for combustion can be estimated by Qair_piégé = Q air mg, - 11 t Equation (13) In Figure 2, these estimates are obtained by means of a divider 43, sending the ratio 13.01 / T , 01 to a multiplier 44 receiving on its other input the fill factor entered riv The result () air mgc is then sent, if necessary, to the estimator 10 of emi pollutants, and is sent to another multiplier 45 receiving on its other input the trapping coefficient laughs. The trapped Qair result is sent to the wealth estimator 2, which then estimates the richness R, for example according to the formula: b Equation (14) Richness R = QcarPCO Q trapped air With PCO: comburivorous fuel power (for example 14.7 for gasoline) The engine 1 of Figure 2 equipped with the pollutant estimator 10, using the same types of equations as those mentioned above to estimate the level of production of one or more polluting species. The engine 1 is equipped with a trap 33 of nitrogen oxides and a trap monitor 20 configured to trigger "purge" phases of the trap, during which the operating conditions of the engine are such that the oxides of nitrogen accumulated in the trap are reduced, at the cost of temporary overconsumption of engine fuel. In the example illustrated in FIG. 2, the production value of nitric oxide is sent to the trap monitor 20, which is a computation unit cumulating, for example using an integrator 21 of the values nitrogen oxide production calculated by the estimator 10.

The monitor 20 comprises a comparator 22 which detects when the total amount of nitrogen oxides accumulated in a decontamination system 33 exceeds a threshold designated herein as "ThresholdCumul". As long as this threshold is not reached, the monitor 20 continues to calculate each increase of the total quantity stored in the pollution control system 33. When the threshold is reached, the trap monitor 20 initiates a procedure 23 which makes it possible to reduce the nitrogen oxides present in the pollution control system 33. The procedure 23, triggered by a purge control unit, may for example consist of modifying the air / fuel ratios sent to the cylinder as well as the pressures in the fuel supply circuit. gas 30, so as to obtain at the cylinder outlet reducing chemical species which will reduce the nitrogen oxides stored in the pollution control system 33. This "purge" operating mode may typically involve a combustion at higher temperature, and thus be less expensive to trigger for some modes of driving than for others. The trigger threshold indicated in step 22 may therefore be a function of the instantaneous driving conditions of the vehicle. In the example illustrated in FIG. 2, the estimation of the total quantity of pollutants accumulated in the pollution control system 33 makes it possible to trigger the elimination phases of these pollutants, which are energy-intensive, only when these phases are really become necessary. FIG. 3 illustrates yet another example of application of an engine equipped with a system 10 for estimating pollutant emissions according to the invention. FIG. 3 shows elements that are common to FIGS. 1 and 2, the same elements being designated by the same references. In the example illustrated in FIG. 3, the vehicle on which the gasoline engine 1 is mounted is also provided with a second electric motor unit 38 comprising, for example, an electric motor 36 and a battery 37. To arbitrate on the distribution of couples to be provided by the internal combustion engine 1 and the electric motor 36, the vehicle is equipped with a power management module 25 "LGE" referenced 25. The Ctot torque setpoint emanating from the pedal 12 is thus transmitted to the energy management module 25 which, depending on the requested torque level, the instantaneous speed of the vehicle, and possibly other parameters, sends a first setpoint torque Cote, the electric motor group 38 and a second Ctherm torque setpoint to a calculation module 24 involved in the regulation of the heat engine 1. The arbitration between the amount of torque to be supplied by the electric motor and the amount of torque to provide for example, the thermal engine can take into account the low efficiency of the heat engine at moderate torques and reduced speeds, for example when starting the vehicle, which is preferably done using the electric motor 36. safe to intervene in the arbitration, such as the level of charge of the battery 37 and / or the reserves of energy available in the battery 37 and in the fuel tank 19. The calculation unit 24, which can play the the role of a moderator module, can return a modified setpoint value Ccons to the energy management module 25, this modified setpoint Ccons being that the control systems of the engine 1 will actually seek to achieve by acting on various parameters of operation, in particular on the position setpoint "u" of the turbine 5b. The energy management module 25 can thus take into account this modified setpoint to compensate the differential between the initial setpoint Ctherm and the modified setpoint Ccons by increasing or decreasing accordingly the setpoint Celec sent to the electric motor 36. The estimator pollutant emissions 10, again using the sets of equations described above, can calculate one or more quantities of polluting species that can read, in one or more maps 26, the correction coefficients of which here only one is represented Kp012. This corrective coefficient may, for example, multiply the setpoint torque Ctherm sent a priori by the management module 25 to the moderator module 24. A multiplier 27 can thus deliver the modified torque setpoint Ccons, on the one hand to the management module. energy 25, and secondly, to a calculator 15 supercharging pressure setpoint Pcons -Paons corresponding to the gas pressure to be reached in the intake manifold 32. This setpoint pressure can then be subtracted, at the level of a subtractor 29, the measured pressure 13.01 delivered by the pressure sensor 9. The deviation from the setpoint c can be sent to a regulator 8 which can be a PID type regulator or another type of regulator and which delivers a control value to the conversion unit 7 which using other control parameters and the value then develops the position setpoint "u" of the blades of the turbine 5b. In the example illustrated in FIG. 3, the pollutant estimator 10 therefore makes it possible to optimize the distribution of couples between thermal engines and electric motors, not only on consumption criteria, which are taken into account at the module level. energy management 25, but also to limit the instantaneous emission, and if possible the global emissions, of one or more polluting species. In the application examples described in FIGS. 1, 2, or 3, which are in no way limiting, a limited number of sensors, sensors which are generally already present for other aspects of the control of the heat engine 1, are therefore used. extracts from the measurements of these sensors, with the aid of the estimator 10, information enabling the control of the internal combustion engine 1 to be adapted in order to limit the polluting discharges thereof. According to the variant embodiments, these sensors may comprise a flowmeter placed to measure the flow of incoming fresh air, or may not include such a flow meter, the estimates of the incoming air flow and of the richness being then, for example, as in the embodiment illustrated in Figure 2. Therefore reduces the ecological footprint of the vehicle, by not modifying almost the engine architecture, and without increasing the cost of the vehicle. The sensors used are already present for other stages of engine control, and are usually already subject to control procedures as the vehicle rolls, which ensures the reliability of the data transmitted to the estimator polluting emissions 10.

The invention is not limited to the embodiments described, and can be declined in many variants. Thus the richness and flow rates of air entering the cylinders and trapped in the cylinders can be estimated in various ways, corresponding to the embodiment of Figure 1, the embodiment of Figure 2, or other modes of realization. Filling coefficient mapping 41 can be used and no trapping coefficient mapping can be used, considering that it is equal to 1 in first approximation. Only mapping that is already the product of filler mapping and trapping mapping can be used, omitting the multiplier 44, if for example there is no need to calculate HC production of unburnt hydrocarbons, and therefore no need to know the total flow of air entering the cylinders Qa '

Claims (10)

REVENDICATIONS1. Internal combustion engine (1), comprising a device (10) for estimating pollutant emissions, the estimating device being configured to calculate a first pollutant value of pollutant emissions taking into account the (N) of rotation of the engine (1), a measured temperature (T) of coolant circulating in the engine (1), a fuel consumption (), (0 in fuel of the engine, an estimated value (R) indicative of the gas entering the cylinders (6) of the engine, and a level of ignition advance ((p) of the engine. An engine according to claim 1, wherein the estimating device (10) is configured to calculate a first pollutant value of pollutants as the product of a first affine function of the fuel consumption (0). a second affine function of the ignition advance (q), a third affine function of the coolant temperature (T), and a negative exponential term of a power of the richness (R) gas entering the cylinders. 3. Motor according to claim 2, the negative term under the exponential function being proportional to a power function of a difference between the richness (R) of gas entering the engine and a threshold richness. An engine according to claim 3, wherein the estimating device (10) is configured to calculate a second pollutant value (Pollut) as a product of an affine function of the temperature (T) of the liquid of cooling by the fuel consumption carb, (0) of the engine, and by a third, affine function of the richness (R) of the gases entering the cylinders of the engine. 5. Motor according to claim 4, wherein, below a threshold richness, the estimation device (10) is configured to replace the third affine function of the richness (R) of the gases entering the engine cylinders by a constant value. 6. Motor according to any one of claims 3 to 5, wherein the estimating device (10) is further connected to a pressure sensor (9) (13,01) in an intake manifold (32). of the engine (1) and a temperature sensor (11) (11) of the gases in the intake manifold (32) of the engine, as well as means for estimating (35) the speed of rotation (N). ) of the engine (1) and an estimation means (44) of the air flow rate (Qair, Qair mgc) entering the engine (1), and wherein the device (10) for estimating polluting emissions is configured to calculate a third Pollut value of pollutant emissions, such as a product of an affine function of ignition timing ((p), by an affine function of the temperature (T) of coolant , multiplied by a first polynomial of the second degree as a function of the inverse of the motor rotation speed (N), by a second polynomial of the second degree depending on the richness (R), and by a third e second degree polynomial function of a reduced variable, the reduced variable being proportional to the air flow rate (Qair, Qair mgc) entering the engine and the temperature (Law) of the gases in the intake manifold, and vice versa proportional to the pressure (13,01) of the gases in the intake manifold (32) of the engine. 7. Motor according to any one of the preceding claims, further comprising a controller (18) configured to take into account a signal of an accelerator pedal, and configured to develop from this signal a position command (u ) of an actuator of the motor (1), by weighting the position setpoint (u) with a mapped value (Kpoli) as a function of at least one pollutant emission value (Pollut) calculated by the estimator (10) emissions. 8. Motor according to any one of claims 1 to 7, comprising a trap (33) polluting species and an estimation device (10) configured to calculate an instantaneous value (pollut) of pollutant emissions corresponding to the species to trap, the engine (1) further comprising a trap monitor (20) configured to determine the amount (Cumul) of pollutant species accumulated in the trap (33) by integrating an estimated value (Pollut) by the device estimate (10). 9. Hybrid vehicle comprising an electric machine (36) and comprising an internal combustion engine (1) according to any one of claims 1 to 8, the vehicle comprising an energy management module (25) configured to deliver a set of instructions (Celec) of electric torque to be supplied by the electric machine (36) and to deliver a desired value (Ctherm) of thermal torque to be supplied by the internal combustion engine (1), the vehicle further comprising a moderator module (24) configured to weight the desired value (Ctherm) of thermal torque according to an estimated value (Pollut) of pollutant emissions, and to deliver a setpoint thermal torque (Ccons) for developing a position command (u) of an actuator of the internal combustion engine (1). A method of managing an internal combustion engine (1), wherein at least one pollutant emission value of a polluting species is estimated using engine parameters other than the gas pressure in the engines. cylinders (6) of the engine (1), at least one polluting emission value being calculated as the product of a first function affine of the fuel consumption, (0 of fuel, of a second, affine function of the advance ((p) on ignition of the engine, a third function refines the temperature (T) of engine coolant, and a negative exponential term of a power of wealth (R) of the combustion mixture in the cylinders (6) of the engine.