Method for parameterizing emission model of internal combustion engine having exhaust gas aftertreatment system

Abstract

The invention relates to a method for parameterizing an emission model of an internal combustion engine having an exhaust gas after-treatment device, comprising the following steps: storing an adaptable emission model, in which engine control data and / or measured values of sensors of the internal combustion engine and / or of the exhaust gas after-treatment device thereof are used as input data, the emission model comprises an algebraic formula with adjustable parameters, and the physical and chemical processes of the internal combustion engine and the exhaust gas aftertreatment equipment thereof are simulated through the algebraic formula; comparing the virtual measurement value calculated by the emission model with the real measurement value recorded by the sensor in the test stand test; minimizing a deviation between the virtual measurement value and the real measurement value by matching adjustable parameters of an algebraic formula of the emission model; a matched emissions model with the determined parameters is stored.

Description

Technical Field

[0001] This invention relates to a method for parameterizing the emission model of an internal combustion engine with an exhaust aftertreatment device. Background Technology

[0002] Modern gasoline internal combustion engines typically employ at least two three-way catalytic converters and a particulate filter as exhaust aftertreatment devices to minimize pollutants as required by law. Diesel engines, in addition to particulate filters, typically include oxidation catalysts, selective catalytic reduction (SCR) catalysts, and ammonia slip catalysts. Because it is not possible to continuously and accurately measure the quantities of various components of emissions generated and released into the environment at the exhaust outlet of the exhaust system within the vehicle, emissions must be calculated based on available vehicle data to comply with on-board monitoring regulations and ensure compliance with legal limits. To this end, emission models have been developed for simulating both the combustion process and the process within the exhaust aftertreatment system to calculate the composition and quantity of exhaust gases emitted into the environment. For example, a combustion-raw emission model for calculating emissions generated during combustion is described in DE 10 2015 207252 A1.

[0003] In addition, modern internal combustion engines contain multiple sensors that control and monitor optimal combustion and subsequent exhaust aftertreatment.

[0004] However, it has been found that feature-map-based emission models are always only valid for specific internal combustion engines, and therefore, separate emission models must be developed for each internal combustion engine and its exhaust aftertreatment device. For this reason, an emission model was created in which the combustion process and the physical and chemical processes of each exhaust aftertreatment device are described separately using algebraic formulas. Although emissions can be approximated for each engine type and size using this emission model by applying algebraic formulas to the exhaust aftertreatment devices present on the internal combustion engine, it has been shown that the accuracy achievable in this way is insufficient for different engine types and sizes. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to provide a method for parameterizing the emission model of an internal combustion engine with an exhaust aftertreatment device, thereby achieving high accuracy of the simulation measurement values ​​for different engines without having to change the emission model itself.

[0006] In the method according to the invention for parameterizing an emission model of an internal combustion engine with an exhaust aftertreatment device, a matchable emission model is first stored, wherein engine control data and / or sensor measurements of the internal combustion engine and / or its exhaust aftertreatment device are used as input data, and the emission model contains algebraic formulas with adjustable parameters by which the physical and chemical processes of the internal combustion engine and its exhaust aftertreatment device are simulated. This emission model thus calculates measured values, particularly emission values ​​of the internal combustion engine or its exhaust aftertreatment device, from the input data (which may in particular include fuel quantity and air quantity, and valve timing) using one or more associated algebraic formulas. The algebraic formulas herein relate at least to the simulation of the exhaust aftertreatment device or the internal combustion engine.

[0007] The adjustable parameters are first set to initial values, which may correspond, for example, to the average of past measurements, and may be formed, for example, by a correction factor or correction and, more specifically, by a correction function. Furthermore, a test bench test is conducted on the internal combustion engine and its exhaust aftertreatment equipment, with the emission model matched to the test bench test, wherein, in addition to the input data of the emission model, actual measurements are recorded by sensors. These actual measurements can be measured at the end of the entire exhaust aftertreatment equipment, downstream of each individual exhaust aftertreatment unit, and at the outlet of the internal combustion engine and in front of the exhaust aftertreatment equipment. This depends in particular on which unit is simulated by a corresponding algebraic formula with adjustable parameters. The output data of the emission model is calculated in parallel with the recording of these actual measurements, forming virtual measurements. These output data, i.e., the virtual measurements calculated using the emission model, are then compared with the actual measurements recorded by sensors. Here, the deviation between the virtual and actual measurements is then minimized by matching the adjustable parameters of the algebraic formula of the emission model. Different known mathematical standard methods, such as least squares, are used for this purpose. The parameters obtained in this way are ultimately stored in the matched emission model, allowing the model to be used for prediction of the corresponding internal combustion engine and its exhaust aftertreatment equipment. Because a generally effective emission model can be used, and this model can be easily matched to the corresponding internal combustion engine and its exhaust aftertreatment equipment, the development time required for an exhaust model to achieve highly reliable exhaust emission prediction is significantly reduced. The virtual emission values ​​determined in this way have high accuracy during subsequent vehicle operation and are correspondingly suitable for onboard monitoring systems.

[0008] Preferably, in the combustion-raw emission model of the first part of forming the emission model, engine geometry data, internal combustion engine operating data and engine control data, fuel injection data, air mass flow rate and fuel composition are used as input data, and the exhaust gas composition, exhaust gas mass flow rate and air-fuel ratio of the exhaust gas downstream of the internal combustion engine combustion chamber are calculated according to one or more associated algebraic formulas having at least one adjustable parameter. λ) is used as output data. If other physical or chemical processes change besides the engine's input data, this adjustable parameter can be used to match the emission model with the engine involved.

[0009] In another implementation, the output data calculated by the combustion-raw emissions model is compared with measurements determined downstream of the combustion chamber by sensors, and the parameters of the algebraic formulas simulating the chemical and physical processes within the internal combustion engine are matched in such a way that the deviation between the output data of the combustion-raw emissions model and the measurements determined downstream of the internal combustion chamber is minimized. Because the operating parameters of the internal combustion engine (such as ignition timing, scavenging element position, injection pressure, and injection timing) are provided within the engine control unit, the physical and chemical combustion processes can be well approximated and modeled using the algebraic formulas of the combustion-raw emissions model, and the exhaust gas composition and mass can be determined. Better consistency is achieved by using this or these additional parameters.

[0010] Furthermore, it is advantageous that in the exhaust gas aftertreatment model, the second part of the emission model, the output data calculated from the combustion-raw emission model or the measurements determined by the sensors of the internal combustion engine, along with individual or associated algebraic formulas simulating the physical and chemical processes within each individual exhaust gas aftertreatment unit, are used to calculate the exhaust gas composition and mass flow rate at the outlet of the exhaust gas aftertreatment unit as output data. In the exhaust gas aftertreatment model, all chemical and physical processes within each exhaust gas aftertreatment unit are therefore simulated and compared at least with the corresponding measurements from the sensors at the outlet of the exhaust gas aftertreatment unit. Thus, for each exhaust gas aftertreatment unit, its algebraic formula contains corresponding adjustable parameters that can be matched to the actual conditions of the corresponding engine at the outlet of the exhaust gas aftertreatment unit, allowing for matching with the corresponding engine and the corresponding exhaust gas aftertreatment unit simply by matching these parameters of the algebraic formula. This results in good emission predictions from the exhaust gas aftertreatment model.

[0011] In another embodiment, an algebraic formula with at least one adjustable parameter is stored in the exhaust aftertreatment model for multiple exhaust aftertreatment devices. The exhaust aftertreatment model calculates respective output data for each of these devices, compares the output data with measurements downstream of each aftertreatment device determined by sensors of the aftertreatment devices and, if necessary, other existing sensors, and matches the adjustable parameter to the algebraic formula simulating the chemical and physical processes within each aftertreatment device such that the deviation between the output data of the exhaust aftertreatment model and the determined measurements downstream of each aftertreatment device is minimized. Therefore, for each aftertreatment device, its process is simulated using an algebraic formula with adjustable parameters, and the corresponding parameters are individually matched to the actual conditions of the corresponding engine. This matching of parameters in the algebraic formulas allows for matching to the actual conditions of each exhaust aftertreatment device for the corresponding engine, resulting in highly accurate emission predictions from the exhaust aftertreatment model for the entire exhaust aftertreatment system.

[0012] To match the parameters of the algebraic formula for the exhaust aftertreatment model, it is preferable to use actual measurements from sensors that measure nitrogen concentration, ammonia concentration, and air-fuel ratio as input values ​​for the exhaust aftertreatment model. These concentrations have actual measurements in modern internal combustion engines because these measurements are present in the onboard monitoring system, allowing data to be read and used for parameter matching without the need for additional sensors on a test bench.

[0013] Furthermore, to match the parameters of the algebraic formulas used to simulate the chemical and physical processes within the catalyst used as an exhaust gas aftertreatment device, it is advantageous to use actual measurements from sensors that measure the concentrations of nitrogen oxides and ammonia upstream and downstream of the corresponding catalyst, respectively. In particular, the chemical processes in existing catalysts can be well simulated using algebraic formulas. The corresponding sensors used to verify the calculated values ​​are located within the exhaust gas aftertreatment equipment or on a test bench, making it easy to use these measurements to match the parameters. Specifically, the actual conversion rate of the catalyst varies slightly depending on the implementation, allowing for a significant improvement in prediction accuracy through parameter matching with the algebraic formulas.

[0014] In another implementation, to match the parameters of the algebraic formula of the exhaust gas aftertreatment model, the output data of the exhaust gas aftertreatment model's nitrogen oxide concentration, ammonia concentration, carbon monoxide concentration, methane concentration, and non-methane hydrocarbon concentration are compared with the measurements of these concentrations at the outlet of the exhaust gas aftertreatment equipment. These sensors are also located at the outlet of the exhaust gas aftertreatment equipment, or can be conveniently installed in the outlet area on a test bench. The existing parameters can be further matched by using additional data on the concentrations of other exhaust gas components, or additional formulas with corresponding parameters can be used according to the emission model to further improve prediction accuracy.

[0015] To obtain reliable sensor measurements to match parameters, stable, defined operating points are run on the test bench, where the input data for the combustion-raw emissions model are constant. This eliminates errors caused by inaccurate values ​​or time delays.

[0016] In another implementation, the system operates at a stable, defined operating point during test bench testing, with defined speeds and load conditions. Such operating points typically also result in constant conditions within the exhaust gas aftertreatment equipment, and consequently, a constant concentration of exhaust gas components.

[0017] In a preferred embodiment of the invention, the parameters for matching the algebraic formula are determined to have constant values ​​throughout the entire operating range. This means determining the optimal values, where the error is minimized at all operating points through parameter matching. This matching requires only a small computational cost in subsequent runs.

[0018] In the alternative design, the parameters for matching the algebraic formula are determined to have at least one value that has a functional correlation with the input data of the emission model (and particularly the input data of the combustion-raw emission model). This functional correlation (e.g., dependence on the existing air-fuel ratio) allows for a more accurate match to real-world conditions, which further improves the prediction of exhaust emissions.

[0019] Therefore, a method is provided for parameterizing an emission model of an internal combustion engine with an exhaust aftertreatment device. Because the emission model can be matched to the corresponding internal combustion engine or its exhaust aftertreatment device, the method can satisfy legal requirements for reliably determining exhaust emissions under all operating conditions. The values ​​determined by the emission model have high accuracy because the emission model is corrected during calculation by incorporating real sensor data used to match parameters present in the algebraic formulas simulating the exhaust aftertreatment device, such that the actual measurements correspond as accurately as possible to the simulation output data. Therefore, a universally effective emission model can be used for different engines and exhaust aftertreatment devices simply by matching it. This significantly reduces the workload for determining an effective emission model. Attached Figure Description

[0020] The following describes an embodiment of the method for parameterizing the emission model of an internal combustion engine with an exhaust aftertreatment device according to the present invention, using a gasoline internal combustion engine as an example, with reference to the accompanying drawings.

[0021] Figure 1 The diagram schematically illustrates the structure of a gasoline internal combustion engine and its exhaust aftertreatment equipment on a test bench, as well as the operating method used to match emission models. Detailed Implementation

[0022] exist Figure 1 The diagram illustrates an internal combustion engine 10. Air is supplied to the engine through an intake manifold 12, within which a throttle valve 14 is arranged to regulate the air volume. Air reaches the combustion chamber 15 of the engine, where gasoline is injected from the fuel rail 17 via an injection valve 16. The gasoline and air in the combustion chamber 15 are compressed, ignited, and burned, and then expelled from the combustion chamber 15 again by piston movement. A first sensor 18 on the test bench 42 is positioned on the combustion chamber, detecting the onset of combustion. From this point, combustion products forming the initial emissions of the engine 10 reach the exhaust manifold 20. An exhaust aftertreatment device 22 is installed in the exhaust manifold 20, where harmful substances in the initial emissions are catalytically converted and filtered to reduce harmful emissions at the end of the exhaust aftertreatment device 22 in accordance with legal regulations.

[0023] Within the exhaust gas aftertreatment device 22, a second sensor 24, in the form of a first oxygen sensor, is arranged downstream of the combustion chamber 15 of the internal combustion engine 10. This second sensor 24 can determine the air-fuel ratio by directly measuring the residual oxygen content. This sensor 24, designed as an oxygen sensor, is located upstream of a first three-way catalytic converter 26 arranged close to the combustion chamber 15 of the internal combustion engine 10. Within the first three-way catalytic converter 26, except for further conversions, carbon monoxide, nitrogen oxides, and unburned hydrocarbons present in the original exhaust gas are primarily converted into carbon dioxide, nitrogen, and water. The first three-way catalytic converter 26 also serves as a first exhaust gas aftertreatment device 27. Downstream of the first three-way catalytic converter 26, a third sensor 28, in the form of an oxygen sensor, is arranged in the exhaust gas aftertreatment device 22. This third sensor 28 measures the residual oxygen content, allowing monitoring of the efficiency or conversion rate of the three-way catalytic converter 26. A fourth sensor 29, configured as a multi-gas sensor, is also arranged, allowing measurement of at least the concentrations of ammonia and nitrogen oxides at this location. This fourth sensor 29 is typically part of the test bench 42. The exhaust gas further flows from here to a particulate filter 31, which serves as another exhaust gas aftertreatment device 30, filtering out soot particles generated during combustion. Downstream of the particulate filter 31, a second three-way catalytic converter 32 is arranged as a third exhaust gas aftertreatment device 33, where unconverted carbon monoxide, nitrogen oxides, and hydrocarbons are converted into carbon dioxide, nitrogen, and water. The exhaust gas then reaches a fifth sensor 34, which is also configured as a multi-gas sensor. This fifth sensor 34 measures the concentrations of oxygen, ammonia, and nitrogen oxides present at this location, and is positioned within the area of ​​the outlet 35 of the exhaust gas aftertreatment device 22. However, only one sensor may be positioned at this location to measure one of the aforementioned concentrations, or three separate sensors may be arranged, each measuring the concentration of one of the aforementioned exhaust gas components. Furthermore, other sensors 36, 38, and 40 are also arranged at the outlet 35 of the exhaust gas aftertreatment device 22 to measure the concentrations of carbon monoxide, methane, and all hydrocarbons, allowing the determination of the concentrations of non-methane hydrocarbons.

[0024] The latter three sensors 36, 38, and 40 are typically measuring elements of the test bench 42 to which the internal combustion engine 10 is connected, and the test bench 42 has a dynamometer 44, through which the load state and speed of the internal combustion engine 10 can be accurately determined or adjusted.

[0025] The internal combustion engine 10 is controlled by an engine control unit 46, which regulates the position of the throttle valve 14, the injection pressure and injection timing of the injection valve 16, and other actuators. The interface of the engine control unit 46 is correspondingly connected to the respective regulators and sensors 24, 28, and 34 (i.e., combustion detection sensor, multi-gas sensor, and oxygen sensor) via electrical connections.

[0026] Furthermore, the engine control unit 46 is connected to the evaluation unit 50 of the test bench 42, making engine control data and the measurements from sensors 24, 28, and 34 fully available to the evaluation unit 50. Additionally, this evaluation unit 50 is connected to sensors 18, 29, 36, 38, and 40 of the test bench 42. However, it should be noted that, depending on the construction of the exhaust aftertreatment device 22, the sensors may be part of the exhaust aftertreatment device 22 or formed on the test bench 42. Sensors not present in the exhaust aftertreatment device 22 may be connected to the evaluation unit 50 of the test bench 42, rather than to the engine control unit 46 of the exhaust aftertreatment device 22.

[0027] Emission model 52 is additionally integrated into engine control unit 46 or evaluation unit 50. Through emission model 52, the emissions produced can be calculated from existing data using algebraic formulas that simulate the chemical and physical processes of the internal combustion engine 10 and its exhaust aftertreatment devices 27, 30, and 33. The algebraic formulas used at least partially include parameters that allow this emission model 52 to be calibrated or parameterized for each internal combustion engine 10 through experiments on test bench 42.

[0028] In this scenario, emission model 52 consists of a combustion-raw emission model 53 and an exhaust aftertreatment model 54. The combustion-raw emission model 53 allows the raw emissions from the operating data of the internal combustion engine 10 to be calculated, while the exhaust aftertreatment model 54 allows the emissions at the outlet 35 of the exhaust aftertreatment device 22 to be calculated from the output data 58 determined by the combustion-raw emission model 53. For this purpose, the operating data of the internal combustion engine 10 is provided to the combustion-raw emission model 53. This operating data, used as input data 56, specifically includes: engine geometry data, data relating to the internal combustion engine load, and engine control data of the internal combustion engine 10, namely, ignition and injection timing as functions of crankshaft angle, operating pressure and temperature, load condition, crankshaft speed, fuel injection data, air mass flow rate as a function of throttle position 14 and valve timing, compression ratio, and fuel composition. For this purpose, the injected fuel mass is first calculated from the fuel pressure and the valve opening time of the injection valve 16. Then, the calculated fuel mass, together with the determined combustion data, air mass, and residual gas share, is used in the combustion-raw emission model 53 to calculate the combustion start time based on the crankshaft angle, the exhaust gas composition downstream of the combustion chamber 15 of the internal combustion engine 10, and the exhaust gas mass flow rate.

[0029] Therefore, the obtained output data 58 is further used as input data 60 for the exhaust gas aftertreatment model 54. In the exhaust gas aftertreatment model 54, the conversion process of the two three-way catalytic converters 26 and 32 and the particulate filter 31 is simulated using algebraic formulas, so that the exhaust gas composition and exhaust gas mass flow rate at outlet 35 can be calculated from the original exhaust gas composition and the original exhaust gas mass flow rate as output data 62 of the exhaust gas aftertreatment model 54. The output data 62 includes values ​​such as nitrogen oxide concentration, ammonia concentration, oxygen concentration, carbon monoxide concentration, methane concentration and non-methane hydrocarbon concentration, which form virtual emission measurements.

[0030] Emission model 52 is first constructed as a universally valid emission model, containing algebraic formulas with adjustable parameters. These formulas simulate processes within the internal combustion engine 10 and existing exhaust aftertreatment devices 27, 30, and 33. To create a parameterized emission model 52 suitable for the tested internal combustion engine 10, corresponding bench tests are performed on the internal combustion engine 10 to match the parameters of emission model 52, thereby reproducing real-world conditions as accurately as possible. For this purpose, the internal combustion engine 10 is subjected to as many different steady-state conditions as possible in terms of load and speed on bench 42. The output data 58, 62 recorded here, as well as the measurements from sensors 18, 24, 28, 29, 34, 36, 38, and 40, are collected within evaluation unit 50 and compared with the data in evaluation unit 50. This can be done in the exhaust gas aftertreatment model 54 or individually for each exhaust gas aftertreatment device 27, 30, 33, at least for those exhaust gas aftertreatment devices 27, 30, 33 simulated by a formula with parameters that provides values ​​as output data 62 for which actual measurements exist within the exhaust gas aftertreatment device 22, or by executing the exhaust gas aftertreatment device 22 as a whole, such that only output data 62 is used. Actual measurements from existing sensors 18, 24, 28, 29 or virtual measurements at their corresponding locations can also be used as input data 60 for each exhaust gas aftertreatment device 27, 30, 33 for further calculations.

[0031] The determined virtual measurement value is then compared with the determined real measurement value. This comparison is illustrated in Figures 64 and 66 as an example of the simulation of the combustion start time and the nitrogen oxide content at the outlet 35 of the exhaust aftertreatment device 22. Here, the first Figure 64 shows a comparison between the simulated measurement value calculated by the combustion-raw emission model 53 and the real measurement value of the first sensor 18 used to detect the start of combustion, and a comparison with the straight line that appears when the simulated measurement value equals the real measurement value. It can be seen that by moving and slightly tilting this straight line, it can be matched well with the determined value pairs, as illustrated in the second Figure 66, which describes the results of the parameterized combustion-raw emission model 53. The movement of this straight line illustrated here can be simply performed by matching the parameters of the formula used to calculate the start of combustion, for example by matching the parameters by minimizing the square of the error. The movement of the straight line thus forms a correction function for matching adjustable parameters.

[0032] Figure 68 in the third figure compares the virtual measurements of the exhaust gas aftertreatment model 54 with the measurements of the fifth sensor 34, where the measurements relate to the nitrogen oxide concentration at outlet 35. It is evident that the straight line representing the state where the virtual measurement equals the actual measurement is located slightly below the actual value pair and rotated slightly to the right. In Figure 70 in the fourth figure, this straight line is again matched with the discovered value pair, and thus the function used to adjust the parameters for forming the minimum deviation between the measurements of sensor 34 and the virtual measurement is determined.

[0033] The parameters obtained in this manner can take the form of correction factors, additive correction terms, and / or correction functions. They can also depend on one or more input data 56, 60, and are subsequently stored in the emission model 52 of the engine control unit 46 to match the emission model 52 with the internal combustion engine 10 under test. Therefore, the output data A of the emission model can be directly corrected by parameter P, i.e., with A... 新 =P*A or A 新 The form =P+A is corrected, and the output data A can also be included in the calculation function of emission model 52. Therefore, for example, the amount of nitrogen oxides m downstream of combustion chamber 15... NOx The combustion-raw emissions model 53 can be used to determine the air-fuel ratio λ and the residual gas fraction R in the cylinder. zyl Combustion center of gravity S v and the temperature T inside the cylinder at ignition zyl The measured values ​​or engine data are used to determine the nitrogen oxide concentration, which in this case are used as input data in the combustion-raw emissions model 53 56. The matching of the determined nitrogen oxide concentration is, in this example, achieved through parameter P. NOx This is done through m Nox =X+Y+Z is achieved, where

[0034] X=f(λ) 2 *c1+f(R zyl ) 2 *c2+f(S V ) 2 -c3

[0035] Y = f(R) zyl )*P NOx *c4+f(SV)*P NOx *c5

[0036] Z = f(λ) * c6 + f(R) zyl )*c7+f(S v )*c8+f(T zyl )*c9+P NOx *c 10 +c 11 ,

[0037] Where c1-c 11 It is a constant value.

[0038] Correspondingly, in this case, the parameter is used as a correction factor in the function used for calculation to match the calculated amount of nitrogen oxides with the measured amount of nitrogen oxides.

[0039] It should be apparent that the parameterization of the emission model performed herein is merely exemplary. A corresponding match can be made for each arbitrary measurement determined by the emission model. This matching does not necessarily require the determination of parameters, which are determined by comparing them with measurements at the outlet. Instead, this parameterization can be performed for each individual exhaust aftertreatment device simulated using a formula incorporating these parameters. Therefore, a large amount of output data can be compared with the corresponding measurements for correction. This method is also applicable to all engines equipped with exhaust aftertreatment devices, i.e., gasoline engines, diesel engines, gas engines, or hydrogen engines. In the structure described herein, the corresponding formulas can also be parameterized using ammonia concentration, hydrocarbon emissions, and methane emissions.

Claims

1. A method for parameterizing an emissions model of an internal combustion engine with exhaust gas aftertreatment, the method having the following steps: - engine control data and / or measured values of sensors (24, 28, 29) of the internal combustion engine (10) and / or its exhaust gas aftertreatment (22) are used as input data (56, 60), and the emissions model comprises an algebraic formula with adjustable parameters, and a simulation of physical and chemical processes of the internal combustion engine (10) and its exhaust gas aftertreatment (22) is carried out by means of the algebraic formula, - a bench test is carried out on the internal combustion engine (10) and its exhaust gas aftertreatment (22) to which the emissions model (52) should be matched, wherein in addition to the input data (56, 60) of the emissions model (52) real measured values are recorded by sensors (18, 24, 28, 29, 34, 36, 38, 40), - output data (58, 62) of the emissions model (52) are calculated, which form virtual measured values, - the virtual measured values calculated by means of the emissions model (52) are compared with the real measured values recorded by means of the sensors (18, 24, 28, 29, 34, 36, 38, 40), - deviations between the virtual measured values and the real measured values are minimized by matching the adjustable parameters of the algebraic formula of the emissions model (52), - the matched emissions model (52) with the determined parameters is stored. - storing the matchable emission model (52), wherein, In a combustion-raw emissions model (53) forming a first part of the emissions model (52), engine geometry data, operating data and engine control data of the internal combustion engine (10), data of fuel injection, air mass flow and fuel composition are used as input data (56), and the composition of the exhaust gas downstream of the combustion chamber (15) of the internal combustion engine (10), the exhaust gas mass flow and the combustion air ratio of the exhaust gas are calculated as output data (58) in accordance with one or more associated algebraic formulae with at least one adjustable parameter. The calculated output data (58) of the combustion-raw emissions model (53) are compared with the measured values downstream of the combustion chamber (15) determined by means of the sensors (24), and the parameters of the algebraic formula simulating the chemical and physical processes within the internal combustion engine (10) are matched in such a way that the deviations between the output data (58) of the combustion-raw emissions model (53) and the determined measured values downstream of the combustion chamber (15) of the internal combustion engine (10) are minimized. ​ ​ ​ ​ 2. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to claim 1, characterized in that ​ 3. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to claim 2, characterized in that ​ 4. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to any one of the preceding claims, characterized in that In the exhaust gas aftertreatment model (54) forming the second part of the emissions model (52), the exhaust gas composition and the exhaust gas mass flow at the outlet (35) of the exhaust gas aftertreatment device (22) are calculated as output data (62) from the calculated output data (58) of the combustion-raw emissions model (53) or from measured values determined by sensors (18, 24, 28, 29) and from individual or interrelated algebraic formulas emulating the physical and chemical processes in each of the exhaust gas aftertreatment devices (27, 30, 33) individually present for the exhaust gas aftertreatment device (22).

5. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to claim 4, characterized in that For a plurality of the exhaust gas aftertreatment devices (27, 30, 33), algebraic formulas with at least one adjustable parameter are stored in the exhaust gas aftertreatment model (54), wherein for each of these exhaust gas aftertreatment devices (27, 30, 33) a respective output data (62) is calculated by the exhaust gas aftertreatment model (54), the output data (62) is compared with measured values determined by sensors (28, 29, 34, 36, 38, 40) downstream of each of these exhaust gas aftertreatment devices (27, 30, 33), and the parameters of the algebraic formulas emulating the chemical and physical processes in each of these exhaust gas aftertreatment devices (27, 30, 33) are adapted such that for each of these exhaust gas aftertreatment devices (27, 30, 33) a deviation between the output data (62) of the exhaust gas aftertreatment model (54) and the determined measured values downstream of each of these exhaust gas aftertreatment devices (27, 30, 33) is minimized.

6. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to claim 5, characterized in that For adapting the parameters of the algebraic formulas of the exhaust gas aftertreatment model (54), real measured values of sensors (24, 28, 29) measuring nitrogen concentration, ammonia concentration and combustion air ratio are used as input data (60) of the exhaust gas aftertreatment model (54).

7. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to claim 5, characterized in that For adapting the parameters of the algebraic formulas emulating the chemical and physical processes in the catalytic converters (26, 32) used as the exhaust gas aftertreatment devices (27, 33), respectively, real measured values of sensors (29, 34) for measuring nitrogen oxide concentration and ammonia concentration upstream and downstream of the respective catalytic converter (26, 32) are used.

8. The method for parameterizing an emission model of an internal combustion engine with exhaust aftertreatment according to any one of claims 4 to 7, characterized in that For adapting the parameters of the algebraic formulas of the exhaust gas aftertreatment model (54), the output data (62) of the exhaust gas aftertreatment model (54) for nitrogen oxide concentration, ammonia concentration, carbon monoxide concentration, methane concentration and non-methane hydrocarbon concentration are compared with measured values of sensors (34, 36, 38, 40) for measuring nitrogen oxide concentration, ammonia concentration, carbon monoxide concentration, methane concentration and non-methane hydrocarbon concentration at the outlet (35) of the exhaust gas aftertreatment device (22).

9. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to any one of the preceding claims, characterized in that A defined operating point is operated stably during a bench test, in which the input data (56) of the combustion-raw emissions model (53) remain constant, respectively.

10. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to claim 9, characterized in that A stable operating limit operating point is run in the test bench test, in which a defined rotational speed and a defined load state exist.

11. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to any one of the preceding claims, characterized in that A constant value is determined for the matching parameter of the algebraic formula over the entire operating range.

12. The method for parameterizing an emission model of an internal combustion engine with exhaust gas aftertreatment according to claim 10, characterized in that A value having a functional dependency on at least one of the input data (56) of the emission model (52) is determined for the matching parameter of the algebraic formula.

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