• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Method for calculating a monitoring criterion which is an indicator of the presence of a SCR catalyst (4) containing zeolites in the exhaust gas duct (1) of a motor vehicle, according to which the criterion of monitoring by calculating the enthalpy difference (wDiff) of the exhaust gas stream on the SCR catalyst (4).
    公开号:FR3044354A1
    申请号:FR1661567
    申请日:2016-11-28
    公开日:2017-06-02
    发明作者:Cornelia Nagel；Tobias Pfister
    申请人:Robert Bosch GmbH；
    IPC主号:
    专利说明:

    Field of the invention
    The present invention relates to a method for calculating a monitoring criterion which is an indicator of the presence of a SCR catalyst containing zeolites in the exhaust gas duct of a motor vehicle. The invention also relates to two computer programs that each perform a step of the method of the invention for calculating and applying the monitoring criterion when the programs are applied by a computer. The invention applies to a machine-readable memory medium that contains the programs. The invention also applies to an electronic control apparatus for carrying out the method of the invention.
    State of the art
    As the limit values for nitrogen oxides NOx emissions are becoming more stringent, different exhaust aftertreatment techniques have been developed to control the emissions of nitrogen oxides NOx contained in the exhaust gases. exhaust of a diesel engine. One of the exhaust aftertreatment techniques is the selective catalytic reduction carried out in an SCR catalyst. For this, the nitrogen oxides contained in the exhaust gas are reduced on an SCR catalyst with ammonia, giving nitrogen (N2). In the case of the use of an SCR catalyst in a construction remote from the engine installed in the exhaust system, aging of such SCR catalyst is relatively limited because the SCR catalyst is exposed to high temperatures, rare, because of the hot exhaust gases and to meet the emission requirements, it is necessary to monitor the operating ability of the SCR catalyst.
    Current SCR catalysts are composed of several components. A honeycomb-like support material has a so-called washcoat coating. This one is formed in particular of zeolites. Zeolites are a finely porous crystalline material used to increase the surface area. The washing coating or its surface comprise catalytically active metals such as in particular copper or iron. It is known that zeolites absorb water and other low molecular weight materials, these materials being restored by heating without the crystal structure being destroyed. A characteristic quantity for exploiting the adsorption and desorption effect of water in zeolites is the adsorption enthalpy. It describes the increase or reduction of the energy content of the zeolite thermodynamic system of the exhaust gas / SCR catalyst.
    DE 10 2009 007 763 A1 discloses a known method for determining an operability of a SCR catalyst subjected to the action of a reducing agent and which is installed in the exhaust gas duct of a combustion engine. internal combustion. With the aid of the SCR catalyst at least one material is fixed in the exhaust gas mixture and the state of charge of the SCR catalyst is determined with a substance of the exhaust gas mixture which is different from the reducing agent and which is fixed by the SCR catalyst. The method described first consists in measuring at least one parameter of the exhaust gas mixture which changes as a function of the efficiency of the SCR catalyst during the passage of the mixture of exhaust gases through the SCR catalyst. From the measured value thus obtained and from a comparative value, a difference is formed which is compared with a set value.
    Description and advantages of the invention
    The subject of the present invention is a method for calculating a monitoring criterion which is an indicator of the presence of an SCR catalyst containing zeolites in the exhaust gas duct of a motor vehicle, the method being characterized in that the monitoring criterion is determined by calculating the enthalpy difference of the exhaust gas stream on the SCR catalyst.
    In other words, the method according to the invention for calculating a monitoring criterion which is an indicator of the presence of an SCR catalyst containing zeolites in the exhaust gas duct of an internal combustion engine. consists in determining the monitoring criterion by calculating the difference in enthalpy of an exhaust gas stream on the SCR catalyst. This method is particularly advantageous because to determine the monitoring criterion it is sufficient to have a temperature sensor downstream of the SCR catalyst, which avoids installing a NOx nitrogen oxide sensor downstream of the SCR catalyst. This solution would be more complicated and more expensive than the use of a temperature sensor. In addition, for the process of the invention, it is not necessary to add an additional material such as a reducing agent.
    Preferably, the monitoring criterion is determined by calculating, using the difference in the measured temperature and the modeled temperature downstream of the SCR catalyst, the difference in enthalpies of the exhaust gas stream. The difference in enthalpies wDiff is calculated as follows:
    (1)
    In this formula:
    Cp.Abgas is the specific heat capacity of the exhaust gases released by the fuel combustion, mAbgas is the mass flow of exhaust gas,
    Tm, 6 is the temperature of the exhaust gas, measured downstream of the SCR catalyst and
    Tmod is the modeled temperature magnitude downstream of the SCR catalyst.
    The value of the enthalpy difference is thus obtained, also from the comparison of the temperature measured downstream of the SCR catalyst, which gives the image of the adsorption and desorption effects of water in the SCR catalyst or in the structure of the catalyst. zeolites of the SCR catalyst and a modeled value that does not take into account this effect. The difference in enthalpy of the exhaust gas vein is thus a measure of the exothermic and endothermic characteristics of the zeolite structure and can be used as a distinguishing criterion, indicating whether the structure of the zeolite is not able to function. . Sufficient differences in enthalpy refer to the ability to
    existing operation. If there are no sufficiently significant differences, that is, if the measured value and the modeled value hardly differ, the zeolite structure is damaged, no longer functional, or probably no longer exists. . The temperatures used for the calculation can be filtered by a low-pass filter before integration into the formula (1) according to one embodiment. The advantage of the low temperature filtering Tmod of the temperature signals is to eliminate any parasitic signals. Alternatively, in formula (1), it is also possible to use the temperature gradient instead of the temperatures.
    According to another characteristic, the sufficiency criterion is monitored by calculating, using the difference of a temperature measured upstream of the catalyst SCR and a temperature measured downstream of the catalyst SCR, the difference is formed. of enthalpy of the exhaust gas vein. In this case, the difference in enthalpy is calculated as follows:
    (2)
    In this formula Tm, 5 and Tm, 6 represent the temperatures measured upstream and downstream of the SCR catalyst. These measured temperatures Tm, 5 and Tm, 6 may be replaced according to one embodiment by the temperatures Tm, 5 and Tm, 6 filtered by a low-pass filter according to the embodiment of formula 2. Alternatively, in place of temperatures, it is also possible to use the temperature gradients. The use of the temperature measured both upstream and downstream of the SCR catalyst is particularly advantageous because it eliminates the formation of model values so that no temperature model is necessary for the presence controls of the SCR catalyst. SCR catalyst.
    In particular, the monitoring criterion is calculated as a function of the amount of water in the SCR catalyst as well as the mass flow rate of the exhaust gases. This process is very advantageous because it
    optimally takes into account the exothermic and endothermic properties of the SCR catalyst for adsorption and desorption of water which have a considerable influence on the evolution of the temperature. If the instant of calculation of the difference of the enthalpies to check the operating ability of the SCR catalyst is chosen too early, the differences of the temperatures corresponding to a difference of the enthalpies may not be sufficiently too pronounced because the exothermic phase of the water adsorption will not have actually begun. If, on the other hand, the time of the comparison is chosen too late, too much water has already passed through the SCR catalyst and the adsorption and desorption effects have already taken place so that it does not occur. there will be more than small differences in temperatures and thus enthalpies.
    Advantageously, the value of the monitoring criterion is calculated as a function of the temperature of the internal combustion engine at start-up. This particularly advantageous procedure ensures that the influence of the starting temperature of the combustion engine is taken into account for the expression of the effect of the temperature and thus of the enthalpy difference. If the internal combustion engine is restarted in the "hot" state, the temperature effect for the adsorption and desorption of the water which results in a difference in enthalpy will be brief and attenuated because at high temperatures the two effects are superimposed and are less accentuated. This is why there will be unambiguous information regarding the presence of an SCR catalyst if the evaluation of the monitoring criterion is done at low engine temperatures and best at cold start.
    At the beginning of a driving cycle, after a sufficiently long stopping time, it can be assumed that the temperatures at the measuring points, ie the temperatures measured upstream and downstream of the SCR catalyst to determine the monitoring criterion, are substantially equal upstream and downstream of the SCR catalyst. If the temperature of the exhaust pipe at the beginning of the driving cycle is too high, for example because the engine has been stopped for a short period of time, the criteria described can not be applied or only very limited to control the presence of the SCR catalyst. Therefore, it is interesting to balance the measuring points of the temperature at the beginning of the driving cycle. Any offset of the sensors can be taken into account in the following calculation for the difference in enthalpy. If one observes increasing deviations of the initial values provided by the temperature sensors, over a prolonged period, it is absolutely not worthwhile to monitor the SCR catalyst with the enthalpy difference and this monitoring can be stopped to avoid wrong results.
    The method according to the invention, the monitoring criterion is executed in particular in several. First, it is checked whether the heating condition of the SCR catalyst is satisfied. Thus, at the beginning of each driving cycle, it is checked whether the SCR catalyst has operated at sufficiently high temperatures in the preceding driving cycle and that the water fixed in the zeolite coating can be sufficiently expelled. For this, one uses, for example, the engine stopping time, the start temperature and / or the final system temperature and / or the average temperature or maximum temperature. The final temperature is the stopping temperature in the previous driving cycle. The amount of added heat passed through the SCR catalyst during the previous driving cycle can serve as a measure of the heating state of the SCR catalyst. Then, the calculation of the monitoring criterion and the amount of water accumulated in the SCR catalyst are started. Then, it is checked whether a sufficient amount of water has arrived in the SCR catalyst since the start of the engine. If the predefined threshold for the quantity of water is reached, a time dependent on the exhaust gas mass flow rate can be expected before operating.
    The method according to the invention of the application of the monitoring criterion thus calculated consists in concluding the presence of an SCR catalyst in the exhaust gas pipe after carrying out the steps of the method of calculating the monitoring criterion. Using these two methods, it is advantageous to simply calculate a monitoring criterion by means of which it is concluded that the presence or the operating ability of a SCR catalyst installed in the gas line exhaust of a motor vehicle; the effects of temperature are taken into account in the calculation of the enthalpy difference on the zeolite coating of the SCR catalyst.
    In particular, it is concluded that there is an SCR catalyst in the exhaust gas line if the monitoring criterion has a value greater than that of a threshold. Comparison of the monitoring criterion and the predefined threshold advantageously makes it possible, with a reduced calculation, to have information as to whether an SCR catalyst is or is not installed in the exhaust gas pipe.
    According to one embodiment, after calculating the monitoring criterion, it is verified for which quantity of water the local maximum of the enthalpy difference is obtained. This method is particularly advantageous because the extreme local values of the enthalpy difference that can be achieved in a certain period of time constitute a particularly significant characteristic for judging SCR catalyst. In an exhaust system equipped with an SCR catalyst, because of the characteristic change in temperature at the beginning of a driving cycle, the calculated enthalpy difference increases strongly over a certain period of time. Depending on the quality of the modeled value used for the temperature downstream of the SCR catalyst, in the following, the enthalpy difference can again decrease. As the distinguishing criterion, the maximum enthalpy difference is applied in a predefined time window. It is a measure of the amount of energy that can be maximally released in the SCR catalyst by the water-zeolite effect. To evaluate the SCR catalyst, it can be related to the moment when the maximum of the enthalpy difference is reached, this quantity of water and that reached from the start of the engine to the SCR catalyst. If the SCR catalyst can still operate, the local maximum of the enthalpy difference is set according to the operating conditions and symmetry tolerances for a characteristic quantity of water. In the opposite case, either the maximum of the enthalpy difference can not be determined, that is the maximum is established at a moment which differs significantly, for example if already a significant quantity of water, visible has arrived in the SCR catalyst.
    According to another development, it is checked if after establishment of the local maximum of the difference of enthalpy, a minimum of the difference of enthalpy is established again.
    According to another embodiment, it is checked whether the minimum of the enthalpy difference is set within the predefined period after the local maximum. The invention also relates to two computer programs for executing each step of the first and / or second method of the invention, in particular when they are applied by a computer or an electronic control device. This makes it possible to implement the method of the invention on an electronic control device without having to modify its construction. The subject of the invention is also a machine-readable memory medium which contains the recording of computer programs as well as an electronic control device for carrying out the method of the invention.
    drawings
    The present invention will be described below, in more detail with the help of examples of method and device for calculating a criterion for monitoring an SCR catalyst represented in the accompanying drawings in which: FIG. 1 is a diagram of an exhaust gas pipe and a control apparatus, - Figure 2 is a flow chart of the flow of a first embodiment of the two methods of the invention, - Figure 3 shows two diagrams for calculating the enthalpy difference according to one embodiment of the invention; - FIG. 4 is a schematic flow diagram of a second embodiment of the two methods of the invention; FIG. 5 is a diagram of a flowchart of a third embodiment of the two processes of the invention, - Figure 6 is a diagram showing the relationship between the maximum difference of enthalpy and the amount of water obtained by integr and Figure 7 shows schematically the flow chart of a fourth embodiment of the two methods of the invention. Description of Embodiments of the Invention
    Figure 1 shows schematically an exhaust pipe 1 of a motor vehicle (it is not shown). This exhaust gas line is equipped with a reducing agent dosing point 2, a particulate filter with a selective catalytic reduction coating SCR 3 (SCROF), a SCR catalyst 4 with a coating of zeolites, a temperature sensor 5 upstream of the catalyst SCR 4, a temperature sensor 6 downstream of the catalyst SCR 4 and a control apparatus 7. The control apparatus 7 comprises a data transmission link with the temperature sensors 5, 6.
    FIG. 2 schematically shows the flowchart of a first embodiment of the method for calculating the monitoring criterion according to the invention. In the first step of the process, the vehicle is started. In the following step 11, it is checked whether the heating condition of the SCR catalyst 4 is satisfied. If, at the beginning of each driving cycle, it is verified whether the SCR catalyst 4 has operated at sufficiently high temperatures in the preceding driving cycle and that the water fixed in the zeolite coating has been sufficiently removed. For this, one uses, for example, the engine stopping time, the system temperature at startup and / or at the end of operation and / or the average temperature or maximum temperature. The final temperature is the temperature at the end of the previous driving cycle. By adding up the amount of water that has passed through the SCR catalyst 4 in the previous driving cycle, this amount is used as a measure of the heating state of the SCR catalyst 4. If the heating condition is not met, a message is issued in step 12 indicating that a diagnosis of the SCR catalyst 4 can not be made in this driving cycle.
    If the heating condition in step 11 is fulfilled, it is expected that there will be a temperature effect sufficiently accentuated by adsorption and desorption of water. In this case, in step 13 the calculation of the enthalpy difference wDiff which serves as a monitoring check and the quantity of water mH20 accumulated in the SCR catalyst 4 is started. In the previous embodiment, the enthalpy difference wDiff according to formula (1) is calculated, that is to say that the enthalpy difference wDiff is calculated from the measured temperature Tm, 6 downstream of the catalyst SCR 4 and the modeled temperature Tmod downstream of the catalyst 4. As the measured temperature Tm, 6 is the image of the effects of adsorption and desorption of water in the SCR catalyst 4 and the modeled temperature Tmod does not take into account such effects, the calculated enthalpy difference wDiff is thus a measure of the endothermic and exothermic characteristics of the zeolite structure of the SCR catalyst 4. This is why the enthalpy difference wDiff, calculated, is a good distinguishing criterion for determining whether the zeolite structure or catalyst SCR 4 are in working order. The calculation of the monitoring criterion is made according to the temperature of the combustion engine at start-up because the starting temperature of the combustion engine has an influence on the expression of the effect of temperature on the catalyst SCR 4.
    Figure 3 shows the calculation of the enthalpy difference wDiff using diagrams. The top diagram shows the plot of the modeled temperature Tmod downstream of the catalyst SCR 4 and the evolution of the measured temperature Tm, 6 downstream of the catalyst SCR 4 as a function of time t in seconds. The bottom diagram shows, on the one hand, the enthalpy difference wDiff as a function of the time t measured in seconds, which was calculated from the temperatures Tmod and Tm, 6 of the top diagram and, on the other hand, the quantity of water mH20, integrated since the start of the engine as a function of time in seconds. The ft arrow or the si star indicate the instant at which one is at the maximum difference of enthalpy wDiffmax. The arrow p2 indicates the time at which the enthalpy difference wDiff is again zero. The arrow p3 or the star s3 mark the moment at which the amount of water mH20 of the catalyst SCR 4 is sufficient and that the monitoring criterion, that is to say the maximum difference of enthalpies wDiffmax (Etoile si) will be exploited. In step 14 it is verified that a sufficient amount of water mH20 has arrived in the SCR catalyst 4 since the start of the engine. In step 14 it is found that there is still a sufficient amount of water mH20 that has arrived in the SCR catalyst 4 so that the previous step 13 will not be performed.
    The method of applying the monitoring criterion thus calculated will be described using the following steps 15-18. In step 14 it was found that to evaluate the monitoring criterion, there is a sufficient amount of water mH20 in the SCR catalyst 4, while in step 15 the maximum value reached of the enthalpy difference is compared. wDiffmax at the predefined threshold vth. If the maximum value of the enthalpy difference wDiffmax is greater than the threshold vth then it is concluded in step 16 of the method that there is a catalyst SCR 4 installed in the exhaust pipe 1 or that the catalyst SCR 4 installed is able to work.
    If the maximum value of the enthalpy difference wDiffmax does not exceed the threshold vth in the predefined duration, step 17 makes it possible to conclude that there is no catalyst SCR 4 in the exhaust pipe or that this one installed there does not work. This is signaled to the control unit 7 in step 18 and subsequent actions are started if necessary, especially if compliance with the limit value of nitrogen oxides NOx is no longer ensured because of the catalyst SCR 4, is defective.
    Figure 4 shows schematically the process flow corresponding to a second embodiment of the invention. Steps 10-12 and 14 of the method of calculating the monitoring criterion are identical to steps 10-12 and step 14 already described. The difference in the method for calculating the monitoring criterion according to the first and second embodiments lies in the fact that, in the second embodiment, in order to calculate the monitoring criterion, the gradients of the temperatures Tmod and Tm are used. in step 111. Then, in step 13 of the method, according to the second embodiment, as in the first embodiment, the monitoring criterion is calculated. For this, in this case, formula (1) is also used but, instead of the temperatures Tmod and Tm, 6, the temperature gradient Tmod and Tm, 6 are used in formula 1. The following steps 15-18 the method of calculating the monitoring criterion are identical to the steps 15-18 described above.
    FIG. 5 schematically shows the progress of the two processes according to the third embodiment of the invention. Steps 10-14 are identical to steps 10-14 of the first exemplary embodiment. Similarly, in this case, as in the first embodiment, in step 13 the enthalpy difference wDiff is calculated. The difference between the first and second embodiments with respect to the third embodiment lies in the fact that the method for applying the calculated monitoring criterion is that of the steps 19 to 23 already described. If, in step 14 it was found that there was a sufficient amount of water ulh2o arrived in the catalyst SCR 4, then, in the subsequent step 19, it is checked for how much water, integrated MH20 we will have the maximum value of the enthalpy difference wDiffmax.
    In order to explain, the maximum difference of enthalpy wDiffmax measured in kJ is plotted in the diagram of FIG. 6 as a function of the quantity of water mH20 measured in kg, the amount of water which has arrived up to that moment in the catalyst SCR 4. If an SCR catalyst 4 is installed in the exhaust gas duct 1 and is able to operate, the local maximum of the enthalpy difference wDiffmax is established as a function of the operating conditions and system tolerances for a characteristic amount of water. In the example shown in Figure 6, this corresponds to a quantity of water between 0.2 and 0.3 kg.
    If, in step 19 of the process, it is found that the maximum value of the enthalpy difference wDiffmax has been established for the characteristic quantity of water, then, in step 20, it is concluded that a SCR catalyst 4 is installed in the exhaust pipe 1 or the installed SCR 4 catalyst is suitable for operation. If in step 19 it is found that there is no maximum of the enthalpy difference wDiffmax or that the maximum of this difference wDiffmax for a quantity of water significantly different from the characteristic quantity, then in the step 20 it is concluded that there is no SCR catalyst 4 in the exhaust pipe 1 or that the SCR catalyst 4 installed is not able to operate. In this case, step 18 is already executed, according to which a message is sent to the control device 7 and the following necessary actions are commanded.
    Figure 7 shows schematically the flow chart of a fourth embodiment of the two methods of the invention. Steps 10-14 and 19 are identical to steps 10-14 and 19 described in the previous embodiment. If, in step 19 of the method of applying the monitoring criterion, it has been found that the maximum value of the enthalpy difference wDiffmax has developed for a characteristic quantity of water, then, in step 22 it is then checked whether, after the maximum of the enthalpy difference wDiffmax, a minimum of the enthalpy difference wDiffmin is established. If so, it is checked in the following step 23 if this minimum of the enthalpy difference wDiffmin has been established within the predefined time tmin, if this is the case in step 20 it is concluded that there is a SCR catalyst 4 installed in the exhaust pipe 1 or the SCR catalyst 4 installed is able to operate. In step 19 it is found that a maximum criterion of the enthalpy difference wDiffmax has not developed and that the maximum of the enthalpy difference wDiffmax is obtained for a very different characteristic quantity of water, so that in step 21 it is concluded that there is no SCR catalyst 4 in the exhaust pipe 1 or that the catalyst therein is not working.
    In step 22, it is found that there is no minimum of the enthalpy difference wDiffmax or that in step 23 it has been found that within the predefined time tmin, it is not a minimum of the enthalpy of wDiffmax is developed so that in step 21 it is concluded that there is no SCR catalyst 4 in the exhaust pipe 1 or that the one installed is not working . In each of these three cases, after step 21, the following step 18 is performed in which an appropriate message is sent to the control device 7 and the following necessary measurements are commanded.
    In the third and fourth embodiments of the invention, as in the second embodiment, temperature gradients can be used.
    According to another development of the calculation method of the monitoring criterion, for the calculation of the enthalpy difference wDiff, the temperature Tm, 6 measured downstream of the catalyst SCR 4 and the modeled temperature Tmod, a temperature Tm, are not used. , Measured upstream of the catalyst SCR 4 and the temperature Tm, 6 measured upstream of the catalyst SCR 4 is used.
    NOMENCLATURE OF MAIN COMPONENTS 1 Exhaust gas line 2 Reducing agent dosing point
    3 SCR coated particle filter
    4 SCR Catalyst 5 Temperature Sensor 6 Temperature Sensor 7 Control Unit 10-18 Process Steps
    权利要求:
    Claims (14)
    [1" id="c-fr-0001]
    CLAIMS 1 °) Method for calculating a monitoring criterion which is an indicator of the presence of a SCR catalyst (4) containing zeolites in the exhaust gas duct (1) of a motor vehicle, characterized in that determining the monitoring criterion by calculating the enthalpy difference (wDiff) of the exhaust gas stream on the SCR catalyst (4).
    [0002]
    2) Method according to claim 1, characterized in that the monitoring criterion is determined by calculating, using the difference between a measured temperature (Tm, 6) and a modeled temperature (Tcal, 6), downstream of the catalyst SCR (4), the difference of the enthalpies (wDiff) of the exhaust valve.
    [0003]
    3) Method according to claim 1, characterized in that the monitoring criterion is determined by calculating the difference of enthalpies (wDiff) of the exhaust gas stream with the difference of the temperature (Tm, 5) measured in upstream of the SCR catalyst (4) and the temperature (Tm, 6) measured downstream of the SCR catalyst (4).
    [0004]
    Method according to Claim 2 or 3, characterized in that the temperature gradient (Tm, 5, Tm, 6, Tmod) is used (111) to calculate the monitoring criterion.
    [0005]
    Process according to one of Claims 1 to 4, characterized in that the value of the monitoring criterion is calculated as a function of the amount of water (mH 2 O) in the SCR catalyst (4).
    [0006]
    6 °) Method according to one of claims 1 to 5, characterized in that one calculates the value of the monitoring criterion as a function of the temperature at the start of the combustion engine.
    [0007]
    7) Method according to one of claims 1 to 6, characterized in that the method comprises the following steps consisting of: a. verify (11) whether the heating condition of the SCR catalyst (4) is satisfied, b. start (13) the calculation of the monitoring criterion and a quantity of water (mH20) accumulated in the catalyst SCR (4) and c. check (14) if a sufficient amount of water has been reached in the SCR catalyst (4) since the start of the engine.
    [0008]
    8 °) Method for applying the calculated monitoring criterion according to any one of claims 1 to 7, characterized in that the method consists in concluding the presence of an SCR catalyst (4) in the gas line of exhaust (1).
    [0009]
    Method according to Claim 8, characterized in that the presence of an SCR catalyst (4) in the exhaust gas duct (1) is determined if the monitoring criterion has a value greater than a threshold (Vth).
    [0010]
    10 °) Method according to one of claims 7 or 8, characterized in that after the calculation of the monitoring criterion, one checks (19) for which amount of water (mH20) establishes the local maximum (wDiffmax) of the enthalpy difference (wDiff).
    [0011]
    Method according to Claim 10, characterized in that (24) is checked whether after adjustment of the local maximum (wDiffmax) of the enthalpy difference (wDiff) a minimum is set again (wDiff- min) of the enthalpy difference (wDiff).
    [0012]
    Method according to Claim 11, characterized in that (25) is checked whether the minimum (wDiffmin) of the enthalpy difference (wDiff) is established in a predefined time interval (tmin) after the maximum local (wDiffmax).
    [0013]
    13 °) computer program designed for the implementation of the method according to any one of claims 1 to 12, a monitoring criterion which is an indicator of the presence of a catalyst SCR (4) containing zeolites in the exhaust gas duct (1) of a motor vehicle, according to which the monitoring criterion is determined by calculating the enthalpy difference (wDiff) of the exhaust gas stream on the SCR catalyst (4).
    [0014]
    14 °) A machine-readable memory medium having the recording of a computer program according to claim 13 and an electronic control apparatus (7) adapted to apply the method according to any one of claims 1 to 12.
    类似技术:
    公开号 | 公开日 | 专利标题
    FR3044354A1|2017-06-02|METHOD FOR CALCULATING A MONITORING CRITERIA FOR DETECTING THE PRESENCE OF A SCR CATALYST CONTAINING ZEOLITES IN THE EXHAUST GAS PIPING AND APPLICATION OF THE CRITERION
    FR2883922A1|2006-10-06|Vehicle`s internal combustion engine controlling method, involves emitting defect signal if conversion signal is less than threshold signal, where conversion signal is determined upstream and downstream of exhaust gas processing unit
    JP2010537117A5|2012-06-07|
    FR2876149A1|2006-04-07|METHOD AND DEVICE FOR DIAGNOSING A NOX NITROGEN OXIDE SENSOR INSTALLED IN AN EXHAUST GAS AREA OF AN INTERNAL COMBUSTION ENGINE
    FR2931879A1|2009-12-04|METHOD AND DEVICE FOR RECOGNIZING COMBUSTION IN A PARTICLE FILTER
    FR2941262A1|2010-07-23|METHOD AND INSTALLATION FOR DIAGNOSING AN EXHAUST GAS PARTICLE FILTER
    FR2878284A1|2006-05-26|METHOD FOR MANAGING AN INTERNAL COMBUSTION ENGINE AND DEVICE FOR IMPLEMENTING SAID METHOD
    FR2897105A1|2007-08-10|Internal combustion engine`s exhaust gas processing device diagnosing method for vehicle, involves measuring pressure of reactive agent between valves and between one of valves and injector
    FR2963388A1|2012-02-03|METHOD FOR DIAGNOSING AN EXHAUST GAS SENSOR AND DEVICE FOR IMPLEMENTING THE METHOD
    FR2914354A1|2008-10-03|METHOD OF DIAGNOSING AN EXHAUST GAS SENSOR INSTALLED IN THE EXHAUST GAS ZONE OF AN INTERNAL COMBUSTION ENGINE AND DIPOSITIVE FOR IMPLEMENTATION
    WO2008142342A2|2008-11-27|Method of monitoring the effectiveness of a catalytic converter storing the noxs located in an exhaust line of an internal combustion engine and engine comprising a device implementing said method
    WO2007090975A2|2007-08-16|SYSTEM AND METHOD FOR THE ELIMINATION OF SOx |, SUPERVISOR FOR SAID SYSTEM
    EP2134940B1|2012-06-20|Method and device for the control of the operating state of a catalytic converter of the exhaust line of an internal combustion engine
    FR2893354A1|2007-05-18|METHOD FOR MANAGING AN EXHAUST GAS TREATMENT DEVICE AND DEVICE FOR IMPLEMENTING THE METHOD
    FR2952124A1|2011-05-06|METHOD AND DEVICE FOR MONITORING AN EXHAUST GAS CLEANING INSTALLATION
    EP1834074B1|2011-03-02|Protecting an oxidation catalyst upstream of a particulate filter for a diesel engine by limitation of injected fuel
    FR2976321A1|2012-12-14|METHOD AND DEVICE FOR DIAGNOSING AN INTERNAL COMBUSTION ENGINE PARTICLE FILTER
    FR2855847A1|2004-12-10|Particle filters load state determining process for internal combustion engine, involves determining pressure variation in upstream of filter in exhaust gas zone, and determining load state of filter from pressure variation
    FR2935432A1|2010-03-05|METHOD AND DEVICE FOR CONTROLLING A FUEL DOSING SYSTEM IN THE EXHAUST GAS CHANNEL OF AN INTERNAL COMBUSTION ENGINE FOR REGENERATING A PARTICLE FILTER
    FR2906312A1|2008-03-28|Exhaust gas sensor diagnosing method for internal combustion engine, involves carrying out diagnosis only if preset variation of engine operating parameter and/or characteristic value of gas is detected during current engine operation
    EP2182191B1|2011-10-19|Method for monitoring a particle filter
    FR3002783A1|2014-09-05|METHOD AND DEVICE FOR MONITORING A NITROGEN OXIDE ACCUMULATOR CATALYST
    FR2818311A1|2002-06-21|Checking NOx sensor in engine exhaust system, initiates rich running to detect low initial ramping rate and low maximum value of ammonia produced
    FR2914693A1|2008-10-10|Gaseous effluent processing unit's i.e. catalytic converter, functioning state diagnosing method for internal combustion engine of motor vehicle , involves comparing test criteria with threshold value defining performance fall of converter
    FR3040074A1|2017-02-17|METHOD FOR DIAGNOSING A SYSTEM COMPRISING A NITROGEN OXIDE ACCUMULATOR CATALYST AND A SCR CATALYST
    同族专利:
    公开号 | 公开日
    FR3044354B1|2020-08-07|
    DE102015223686A1|2017-06-01|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    FR3081917A1|2018-05-29|2019-12-06|Renault S.A.S|SYSTEM AND METHOD FOR ESTIMATING THE PRESENCE OF A CATALYSIS MONOLITE OF AN EXHAUST GAS CATALYSIS SYSTEM OF AN INTERNAL COMBUSTION ENGINE FOR A MOTOR VEHICLE.|
    FR3106366A1|2020-01-21|2021-07-23|Renault S.A.S.|A method of monitoring the operational condition of a selective catalytic reduction system for nitrogen oxides for a vehicle.|DE102009007763B4|2009-02-06|2021-08-12|Audi Ag|Method for determining the effectiveness of an SCR catalytic converter|JP6780763B2|2018-12-25|2020-11-04|トヨタ自動車株式会社|Internal combustion engine control device|
    US11149615B2|2018-12-25|2021-10-19|Toyota Jidosha Kabushiki Kaisha|Control device for internal combustion engine|
    CN111878204B|2020-07-21|2021-09-03|同济大学|Fault diagnosis method for diesel oxidation catalyst|
    法律状态:
    2017-11-24| PLFP| Fee payment|Year of fee payment: 2 |
    2018-11-16| PLSC| Publication of the preliminary search report|Effective date: 20181116 |
    2019-11-21| PLFP| Fee payment|Year of fee payment: 4 |
    2020-11-19| PLFP| Fee payment|Year of fee payment: 5 |
    2021-11-19| PLFP| Fee payment|Year of fee payment: 6 |
    优先权:
    申请号 | 申请日 | 专利标题
    DE102015223686.2A|DE102015223686A1|2015-11-30|2015-11-30|Method for calculating and using a monitoring criterion|
    [返回顶部]