Engine data processor and computer-implemented method for adjusting an exhaust gas composition

Abstract

Engine data processor (1) for adjusting an exhaust gas composition (25) for an internal combustion engine, wherein the engine data processor (1) is configured to receive a geometric characteristic (10) of a discharge unit (11) through which the exhaust gas composition (25) can be discharged, and to determine a smoke visibility limit (21,3) from this, to receive filter fill state information (20) of an exhaust gas filter (16) designed to filter the exhaust gas composition (25), to receive a mean catalyst temperature (22) of an exhaust gas catalyst (18) designed to catalyze the exhaust gas composition (25), and to determine a nitrogen dioxide conversion rate (12) as a function of the filter fill state information (20) and the mean catalyst temperature (22), and to determine the nitrogen dioxide conversion rate (12) and the smoke visibility limit (21,3) to compare them with each other and to determine a control variable (5) for the internal combustion engine such that the exhaust gas composition (25) is invisible, and to output the control variable (5).

Description

[0001] The present invention relates to an engine data processor according to independent claim 1. It further relates to a computer-implemented method for adjusting an exhaust gas composition according to independent claim 12.

[0002] Internal combustion engines are often equipped with control units. These units receive and evaluate sensor data, process it using algorithms, and determine and output control signals. The control signals output by a controller are usually intended to operate various actuators of the internal combustion engine within safe limit ranges. These limit ranges can, for example, define a permissible temperature range or a permissible pressure range.

[0003] Internal combustion engines are used in vehicles as drive systems or in buildings in combination with a generator as a power supply unit. In an internal combustion engine, fuel is burned, producing mechanical power. This power can be used to drive a vehicle or a generator.

[0004] Internal combustion engines must be operated in such a way as to comply with legal emission limits. A legal emission limit often includes a limit for the maximum amount of nitrogen oxides that may be emitted as exhaust gas by the internal combustion engine. Such a limit is usually stored, preferably, in the engine's control unit. During operation, several sensors monitor the engine's condition. The engine's control unit evaluates these state variables and calculates several control variables, which are used to operate actuators that are part of the engine. This allows the engine to deliver the mechanical power for which it was designed, to remain in a safe condition at all times, and to comply with legal emission limits.

[0005] An internal combustion engine of the type mentioned above is designed to monitor the amount of nitrogen oxides emitted and to comply with the emission limits regarding the maximum permissible amount of nitrogen oxides.

[0006] One disadvantage for operators of conventional internal combustion engines is that the engine can emit visible smoke, even if it complies with all legal emission standards. Visible smoke emitted by an internal combustion engine is more likely to soil and discolor the surface of objects or components located near the engine. Therefore, internal combustion engines that emit visible smoke are becoming increasingly undesirable for a growing number of operators. DE 10 2014 002037 A1 discloses an NO2 visibility control for passively regenerating DPF systems.

[0007] The invention is based on the objective of enabling cost-effective, safe, and clean operation of internal combustion engines that produce no visible smoke. In particular, an improved internal combustion engine is to be provided that complies with all legal emission requirements and does not emit any visible, yellow smoke induced by nitrogen dioxide.

[0008] The problem is solved with a motor data processor according to independent claim 1.

[0009] An engine data processor according to the invention for an internal combustion engine serves to adjust the composition of the exhaust gas. The exhaust gas composition includes a certain amount of nitrogen oxides. For example, the exhaust gas composition exits an internal combustion engine or an exhaust aftertreatment system connected to an engine. In particular, the engine data processor serves to adjust the amount of nitrogen dioxide in the exhaust gas composition.

[0010] The engine data processor is designed to receive a geometric characteristic of a discharge unit through which the exhaust gas composition can be discharged and to determine a smoke visibility limit from this. The discharge unit can be assigned to the internal combustion engine or be part of an exhaust aftertreatment system separate from the internal combustion engine.

[0011] The smoke visibility limit is a nitrogen dioxide limit below which no visible smoke escapes from the exhaust unit, but above which visible smoke is to be expected. This value can be determined, for example, using a reference table that lists values ​​for a quantity, such as a nitrogen oxide emission value, along with corresponding values ​​for the geometric characteristic.

[0012] For example, the smoke visibility limit is a nitrogen dioxide limit that should not be exceeded in order to remain invisible. Alternatively, the smoke visibility limit is a nitrogen dioxide limit that may be included in the exhaust gas composition to remain invisible, but exceeding this limit makes the exhaust gas composition visible.

[0013] The exhaust unit is designed, for example, as a cylindrical chimney. A cylindrical chimney offers a flow geometry that is gentle on the machinery and the exhaust gas composition.

[0014] The geometric characteristics of the exhaust unit include, for example, its diameter, cross-sectional area, or radius. In particular, the diameter of the exhaust unit has proven to be a geometric parameter that significantly influences the visibility of the exhaust gas composition, although this value typically varies in each system employing an internal combustion engine.

[0015] Furthermore, the engine data processor is designed to receive filter fill status information from an exhaust gas filter designed to filter the exhaust gas composition. This filter fill status information indicates the fill level of the exhaust gas filter, which can be, for example, empty, partially filled, or full.

[0016] Advantageously, the engine data processor is designed to receive filter fill status information from an exhaust gas filter designed to filter the exhaust gas composition and to determine a series of nitrogen dioxide conversion rates based on this filter fill status information. A nitrogen dioxide conversion rate indicates the value of a certain amount of nitrogen dioxide in the exhaust gas composition. The series of nitrogen dioxide conversion rates indicates the values ​​that the amount of nitrogen dioxide in the exhaust gas composition can assume when the exhaust gas composition is filtered at a filter fill status according to the received filter fill status information.

[0017] The engine data processor is further designed to receive an average catalyst temperature of an exhaust gas catalyst designed to catalyze the exhaust gas composition and to determine a nitrogen dioxide conversion rate depending on the received filter fill state information and the average catalyst temperature.

[0018] Advantageously, the engine data processor is designed to determine a nitrogen dioxide conversion rate from a specific series of nitrogen dioxide conversion rates, depending on the received mean catalyst temperature.

[0019] The nitrogen dioxide conversion rate, determined as a function of the mean catalyst temperature and the filter fill level information, indicates the amount of nitrogen dioxide present in the exhaust gas composition after catalysis in the exhaust catalyst at the mean catalyst temperature and after filtration in the exhaust filter at the measured filter fill level. Taking the mean catalyst temperature and the filter fill level into account allows for a precise determination of the nitrogen dioxide conversion rate.

[0020] The engine data processor is designed to compare the calculated nitrogen dioxide conversion rate and the smoke visibility limit value and to determine a control variable for the internal combustion engine so that the exhaust gas composition is invisible, and to output the control variable.

[0021] By incorporating the geometric characteristics of the exhaust unit when determining the control variable for internal combustion engine operation, an important, customer-specific operating attribute is taken into account to ensure a permanently invisible exhaust gas composition. Considering the geometric characteristics allows each engine data processor to be configured according to the installation conditions of the corresponding internal combustion engine, enabling clean and cost-effective operation with a clean and invisible exhaust gas composition, regardless of the engine's installation space.

[0022] The solution according to the invention can be improved by various embodiments, each advantageous in itself and arbitrarily combinable with one another. These embodiments and their associated advantages are discussed below. The advantages described with regard to the engine data processor and the internal combustion engine also apply to the computer-implemented method according to the invention, and vice versa.

[0023] In its initial configuration, the engine data processor is designed to receive a nitrogen oxide emission value and a pressure value from the exhaust unit, and to determine the smoke visibility limit from these values. Considering these parameters at the exhaust unit allows for a more precise determination of the smoke visibility limit.

[0024] Advantageously, the engine data processor is designed to receive the exhaust filter pressure value and the exhaust unit pressure value, and to determine the filter condition information from these values. Utilizing the filter and exhaust unit pressure values ​​enables a precise, real-time determination of the filter condition, which in turn allows for a more accurate determination of the nitrogen dioxide conversion rate.

[0025] In a further embodiment, the engine data processor is designed to receive a filter temperature and a catalyst temperature and to measure the mean catalyst temperature from these. This enables the determination of a more accurate mean catalyst temperature and, consequently, a more accurate determination of the nitrogen dioxide conversion rate.

[0026] Preferably, the engine data processor is designed to suppress yellow smoke and is further configured to determine at least one smoke visibility limit value, configured as a yellow smoke visibility limit value, and to determine the control variable for an internal combustion engine such that the generation of yellow smoke is suppressed. Yellow smoke is a type of visible smoke that very often occurs during the operation of internal combustion engines.

[0027] Preferably, the engine data processor includes a conversion unit configured to calculate a series of increased or decreased nitrogen conversion rates depending on the filter fill level information. Advantageously, the engine data processor includes a conversion unit configured to calculate lower nitrogen conversion rates as the exhaust filter fill level increases. This allows for continuous adjustment of the calculated nitrogen conversion rates to the currently determined filter fill level and contributes to a more accurate determination of the nitrogen dioxide conversion rate.

[0028] In an advantageous embodiment, the engine data processor comprises a model predictive controller, wherein the model predictive controller includes a limiting unit configured to receive the nitrogen dioxide conversion rate and the smoke visibility limit and to establish an operating limit for setting an invisible exhaust gas composition for the internal combustion engine. This enables cost-optimized operation of the internal combustion engine and the simultaneous avoidance of visible smoke.

[0029] The problem initially set out can also be solved by an internal combustion engine, wherein the internal combustion engine comprises an engine data processor according to one of the above configurations, an engine for providing mechanical power and an exhaust aftertreatment system which includes the exhaust catalyst and the exhaust filter.

[0030] Thanks to the described features of the engine data processor, the internal combustion engine according to the invention can be operated with optimal operating costs and without visible smoke. In particular, the adjustment of the exhaust gas composition, taking into account the engine installation space and the geometric characteristics of the exhaust unit, can advantageously be carried out entirely internally in the engine data processor and thus in the internal combustion engine.

[0031] In an advantageous embodiment, the model predictive controller is designed to generate operating-optimal controller settings for adjusting the mean catalyst temperature from the operating limit. This enables the creation of commands with which the detected mean catalyst temperature can be actively influenced, thus enabling not only the invisible exhaust gas composition but also cost-optimized operation of the internal combustion engine.

[0032] Preferably, the internal combustion engine includes an actuator controller configured to receive operating-optimal control inputs and use them to determine the manipulated variable for an actuation group of the engine. This manipulated variable consists, for example, of commands to actuate an actuation group configured as valves within the engine for a specific duration and in a specific sequence, such that a specific engine exhaust gas temperature can be set to influence the mean catalyst temperature in a cost-optimized manner. This makes it possible to use the engine exhaust gas temperature to influence the mean catalyst temperature, thus enabling cost-effective operation of the internal combustion engine.

[0033] The problem initially set out can also be solved by a computer-implemented method according to independent claim 12.

[0034] A computer-implemented method for adjusting a filtered and catalyzed exhaust gas composition at a discharge unit of an internal combustion engine comprises the following steps: Receiving a geometric characteristic of the exhaust unit, determining a smoke visibility limit from the geometric characteristic, receiving a mean catalyst temperature and filter fill state information, determining a nitrogen dioxide conversion rate as a function of the catalyst temperature and the filter fill state information, comparing the determined smoke visibility limit with the nitrogen dioxide conversion rate, and determining a control variable with which the internal combustion engine is operated so that the exhaust gas composition to be discharged at the exhaust unit is invisible.

[0035] This method is advantageous because it enables cost-effective operation of internal combustion engines without visible smoke. Considering the geometric characteristics of the exhaust system allows for precise determination of the control parameters and flexible adaptation of the method to exhaust systems with varying geometric characteristics. Taking into account the mean catalyst temperature and filter fill level information further enhances the accuracy of exhaust gas composition adjustment.

[0036] The invention is explained in more detail below by way of example with reference to the drawings. The combination of features shown as examples in the embodiments illustrated can be supplemented by further features according to the above explanations, in accordance with the properties of the engine data processor and / or internal combustion engine according to the invention that are necessary for a specific application. Likewise, individual features can be omitted in the described embodiments according to the above explanations if the effect of that feature is not important in a specific application.

[0037] In the drawings, the same reference symbols are always used for elements of the same function and / or structure.

[0038] They show: Fig. 1 : a schematic representation of an engine data processor according to an exemplary embodiment; Fig. 2 : a schematic representation of an internal combustion engine according to an exemplary embodiment; Fig. 3 : a representation of two different filter filling states and the determination of a series of nitrogen dioxide conversion rates depending on them; and Fig. 4 : a schematic representation of a computer-implemented method according to an exemplary embodiment.

[0039] The following describes a motor data processor 1 according to the invention with reference to Fig. 1 described. Furthermore, an internal combustion engine 30 according to the invention is described based on the Fig. 2 and a method according to the invention 100 based on Fig. 4 described.

[0040] In Fig. 1 A simplified, schematic representation of the engine data processor 1 is shown. The engine data processor 1 can have a standalone processor board 6 and / or be integrated on a board of the internal combustion engine 30 (not shown). The units, blocks, and modules of the engine data processor 1 described below can each be implemented in hardware, software, or a combination of both.

[0041] The engine data processor 1 is designed to adjust the exhaust gas composition 25 for an internal combustion engine. The exhaust gas composition 25 contains a certain amount of nitrogen oxides and exits from an engine 19 or from a discharge unit 11 of an exhaust aftertreatment system 42.

[0042] The engine data processor 1 can, for example, have a discharge data interface 33 at which it receives a geometric characteristic 10 of the discharge unit 11 through which the adjustable exhaust gas composition 25 can be discharged. The discharge unit 11 is, for example, an arrangement of several cylindrical chimneys 23, and the geometric characteristic 10 is, for example, a diameter 24 of a chimney 23. Alternatively, the geometric characteristic 10 can be a cross-sectional area of ​​all chimneys 23 (not shown).

[0043] The engine data processor 1 is configured to determine a smoke visibility limit 21 depending on the geometric characteristic 10. The smoke visibility limit 21 is a specific value of a physical quantity at which no visible smoke 2 escapes from the exhaust unit 11, but above which visible smoke 2 is to be expected. This value can be determined, for example, using a unit 8 containing a reference table (not shown) for determining a smoke visibility limit, in which values ​​of a quantity, such as a nitrogen oxide emission value, are compiled with corresponding values ​​of the geometric characteristic 10. Preferably, the smoke visibility limit 21 is a nitrogen dioxide limit.

[0044] For example, the smoke visibility limit 21 is an exclusionary nitrogen dioxide limit that the exhaust gas composition 25 must not exceed in order to remain invisible. Alternatively, the smoke visibility limit 21 is an inclusive nitrogen dioxide limit that the exhaust gas composition 25 may exceed in order to remain invisible, but exceeding this limit results in the exhaust gas composition 25 becoming visible.

[0045] Furthermore, the engine data processor 1 can have a filter status data input 51, at which filter fill status information 20 of an exhaust gas filter 16 designed to filter the exhaust gas composition 25 can be received (see Fig. 2 ). The received filter fill status information 20 includes a statement about how empty or full the exhaust gas filter 16 currently is and has an effect on the amount of nitrogen dioxide present in the exhaust gas composition 25 after it has been filtered.

[0046] Furthermore, the engine data processor 1 can have a temperature data input 31 at which a mean catalyst temperature 22 of an exhaust catalyst 18 designed to catalyze the exhaust gas composition 25 can be received (see Fig. 2 ). The mean catalyst temperature 22 has an effect on the amount of nitrogen dioxide present in the exhaust gas composition 25 after it has been catalyzed.

[0047] The engine data processor 1 is advantageously configured to calculate a series 28 of nitrogen dioxide conversion rates 12, depending on the received filter fill level information 20. A nitrogen dioxide conversion rate 12 indicates the value of a quantity of nitrogen oxide in the exhaust gas composition 25 that is converted into nitrogen dioxide during exhaust aftertreatment, for example in the exhaust aftertreatment system 42. It has been recognized that the nitrogen dioxide conversion rate plays an important role in the formation of visible smoke 2, in particular yellow smoke.

[0048] The series 28 of nitrogen dioxide conversion rates 12 indicates the values ​​that the amount of nitrogen dioxide in the exhaust gas composition 25 can assume when it is filtered in the exhaust gas filter 16 at a filter fill state according to the filter fill state information 20.

[0049] The engine data processor 1 is further designed to determine a nitrogen dioxide conversion rate 12 depending on the received filter fill state information 20 and the mean catalyst temperature 22.

[0050] The nitrogen dioxide conversion rate 12, determined as a function of the mean catalyst temperature 22 and the filter fill state information 20, indicates the amount of nitrogen dioxide present in the exhaust gas composition 25 after catalysis in the exhaust catalyst 18 at the mean catalyst temperature 22 and after filtration in the exhaust filter 16 at the filter fill state recorded in the filter fill state information 20. Considering the mean catalyst temperature 22 and the filter fill state information 20 enables a precise determination of the nitrogen dioxide conversion rate 12.

[0051] Fig. 3 The figure exemplifies the relationship between two different filter fill state information 20 in different time periods T1 and T2 (top left, bottom left) and the determination of the series 28 of nitrogen dioxide conversion rates 12 based on this information.

[0052] An axis Y20a shows the level of a filter fill level information 20 in a first period T1 at the top left. The level of the filter fill level information 20 along the axis Y20a is high and indicates a full exhaust filter 16. Fig. 3 In the upper right, a first curve 40 and a second curve 50 were plotted, representing possible series of nitrogen dioxide conversion rates 12 (axis Y12a) as a function of the mean catalyst temperature 22 (axis X22a). Since the exhaust filter 16 is filled (see upper left, axis Y20a), the first curve 40 is determined as series 28 of the nitrogen dioxide conversion rates 12, and the second curve 50 is not considered further.

[0053] In contrast, in the lower left, the level of the filter fill level information 20 is low during a period T2 (axis Y20b), indicating an empty or barely filled exhaust filter 16. This means that, in the lower right, the second curve 50 with the higher nitrogen dioxide conversion rates 12 is determined from the possible curves 40 and 50 and becomes series 28 of the nitrogen dioxide conversion rates 12, and in this case, the first curve 40 is not considered further.

[0054] How Fig. 3 , right, can be taken, from the selected series 28 of nitrogen dioxide conversion rates 12 depending on the mean catalyst temperature 22 received by the engine data processor 1, the nitrogen dioxide conversion rate 12 can be determined which corresponds to the conditions under which the exhaust gas composition 25 has been treated.

[0055] Advantageously, the engine data processor 1 is designed to determine a nitrogen dioxide conversion rate 12 depending on the received mean catalyst temperature 22 from the series 28 of nitrogen dioxide conversion rates.

[0056] The engine data processor 1 is configured to compare the calculated nitrogen dioxide conversion rate 12 and the smoke visibility limit 21, and to determine a control variable 5 for the internal combustion engine such that the exhaust gas composition 25 is invisible, and to output the control variable 5. The engine data processor can have an output data interface 39 for outputting the control variable 5.

[0057] By including the geometric characteristic 10 of the exhaust unit 11 when determining the control variable 5 for internal combustion engine operation, an important, customer-specific operating attribute is taken into account to achieve a permanently invisible exhaust gas composition 25. By considering the geometric characteristic 10, each engine data processor 1 can be configured, depending on the installation conditions of the corresponding internal combustion engine, so that, regardless of the internal combustion engine's installation space, clean and cost-effective internal combustion engine operation with a clean and invisible exhaust gas composition 25 can be enabled.

[0058] Furthermore, by taking into account the catalyst temperature 22 and the filter fill state information 20, an accurate nitrogen dioxide conversion rate 12 is determined, which reflects at any time, for example also in real time, the conditions under which the exhaust gas composition 25 is post-treated, thereby increasing the setting accuracy of the exhaust gas composition 25.

[0059] The internal combustion engine 30 according to Fig. 2 The system comprises the engine data processor 1, an engine 19 for providing mechanical power 43, and an exhaust aftertreatment system 42, which includes the exhaust catalyst 18 and the exhaust filter 16. Advantageously, the exhaust aftertreatment system 42 can include the discharge unit 11. The engine 19 is operated, for example, with a fuel 44.

[0060] Thanks to the described features of the engine data processor 1, the internal combustion engine 30 according to the invention can be operated with optimal operating costs and without visible smoke 2. In particular, the adjustment of the exhaust gas composition 25, taking into account the engine installation space (not shown) and the geometric characteristics 10 of the exhaust unit 11, can advantageously be carried out completely internally in the engine data processor 1 and thus in the internal combustion engine 30.

[0061] In an advantageous embodiment, the engine data processor 1 is configured to receive a nitrogen oxide emission value 9 and an exhaust unit pressure value 13 detected at the exhaust unit 11 and to determine the smoke visibility limit 21 from these values. Taking these parameters into account at the exhaust unit 11 enables a more precise determination of the smoke visibility limit 21. Advantageously, the internal combustion engine 30 comprises a first pressure sensor 47 for measuring the exhaust unit pressure value 13 and a gas concentration sensor 49 for detecting the nitrogen oxide emission value 9.

[0062] Advantageously, the engine data processor 1 is configured to receive a filter pressure value 14 of the exhaust filter 16 and the discharge unit pressure value 13, and to determine the filter status information 20 from the discharge unit pressure value 13 and the filter pressure value 14. The use of the filter pressure value 14 and the discharge unit pressure value 13 enables a precise determination of the filter status information 20 in real time, which allows for a more accurate determination of the nitrogen dioxide conversion rate 12. In an advantageous embodiment, the internal combustion engine 30 includes a second pressure sensor 48 for measuring the filter pressure value 14.

[0063] In a further embodiment, the engine data processor 1 is configured to receive a filter temperature 15 and a catalyst temperature 17 and to measure the mean catalyst temperature 22 from these. This enables a more precise determination of the mean catalyst temperature 22 and, consequently, also a more precise determination of the nitrogen dioxide conversion rate 12. Preferably, the internal combustion engine 30 comprises a first temperature sensor 45 for measuring the filter temperature 15 and a second temperature sensor 46 for measuring the catalyst temperature 17.

[0064] Preferably, the engine data processor 1 is designed to suppress yellow smoke and is further configured to determine at least one smoke visibility limit 21, configured as a yellow smoke visibility limit 3, and to determine the control variable 5 for the internal combustion engine 30 such that the generation of yellow smoke is suppressed. Yellow smoke is a type of visible smoke 2 that occurs very frequently during the operation of internal combustion engines.

[0065] Preferably, the engine data processor 1 comprises a conversion unit 32 configured to calculate a series 28 of increased or decreased nitrogen conversion rates 12, depending on the filter fill level information 20. Advantageously, the engine data processor 1 comprises a conversion unit 32 configured to calculate lower nitrogen conversion rates 12 with increasing exhaust filter fill level. This enables a continuous adjustment of the calculated nitrogen conversion rates 12 to the currently determined filter fill level and contributes to a more accurate determination of the nitrogen dioxide conversion rate 12. The operation of the conversion unit 32 can advantageously be illustrated in the figure below. Fig. 3 are equivalent to.

[0066] In an advantageous embodiment, the engine data processor 1 comprises a model predictive controller 35, wherein the model predictive controller 35 includes a limiting unit 41 configured to receive the nitrogen dioxide conversion rate 12 and the smoke visibility limit 21, compare them, and thereby establish an operating limit 34 for setting an invisible exhaust gas composition 25 for the internal combustion engine 30. This enables cost-optimized operation of the internal combustion engine and simultaneously avoids visible smoke 2.

[0067] In an advantageous embodiment, the model predictive controller 35 is configured to generate operationally optimal controller settings 38 for adjusting the mean catalyst temperature 22. This enables the creation of commands with which the detected mean catalyst temperature 22 can be actively influenced in order to enable not only the invisible exhaust gas composition 25 but also cost-optimized operation of the internal combustion engine 30.

[0068] Preferably, the internal combustion engine 30 comprises an actuator controller 37 configured to receive the operating-optimal controller parameters 38 and to determine the manipulated variable 5 for an actuation group 29 of the engine 19 from these parameters. The manipulated variable 5 consists, for example, of commands to actuate an actuation group 29, configured as valves, in the engine 19 for a specific duration and in a specific sequence, such that a specific engine exhaust gas temperature 4 can be set to influence the mean catalyst temperature 22 in a cost-optimal manner. This makes it possible to use the engine exhaust gas temperature 4 to influence the mean catalyst temperature 22, thus enabling cost-effective operation of the internal combustion engine.

[0069] The motor data processor 1 advantageously comprises a control unit 36, which includes the model predictive controller 35 and the actuator controller 37.

[0070] In an advantageous embodiment, the motor data processor 1 can have an input data interface 27 via which the control unit 36 ​​can receive operating parameters 26 from the motor 19 in order to monitor the operation of the actuation group 29 designed as valves.

[0071] Advantageously, the engine data processor includes a data memory 7 in which data from unit 8 for determining a smoke visibility limit, conversion unit 32, and control unit 36 ​​can be stored. These units can also access the data. In this way, the representation from Fig. 3 , on the right, next to the row 28 of nitrogen dioxide conversion rates 12, a current smoke visibility limit value 21.3 is also plotted.

[0072] According to Fig. 4A computer-implemented method 100 for adjusting a filtered and catalyzed exhaust gas composition 25 at a discharge unit 11 of an internal combustion engine 30 comprises the following steps: 101: Receiving a geometric characteristic 10 of the exhaust unit 11, 102: Determining a smoke visibility limit 21.3 from the geometric characteristic 10, 103: Receiving a mean catalyst temperature 22 and a filter fill state information 20 and determining a nitrogen dioxide conversion rate 12 as a function of the catalyst temperature 22 and the filter fill state information 20, 104: Comparing the determined smoke visibility limit 21.3 with the nitrogen dioxide conversion rate 12 and, 105: Determining a control variable 5 with which the internal combustion engine 30 is operated so that the exhaust gas composition 25 to be discharged at the exhaust unit 11 is invisible.

[0073] Method 100 is advantageous because it enables cost-effective operation of internal combustion engines without visible smoke 2. Consideration of the geometric characteristics 10 of the exhaust unit 11 allows for precise determination of the control variable 5 and flexible adaptation of Method 100 to exhaust units 11 with different geometric characteristics 10. Consideration of the mean catalyst temperature 22 and the filter fill level information 20 increases the accuracy of adjusting the exhaust gas composition 25.

Claims

1. Engine data processor (1) for setting an emerging exhaust gas composition (25) for an internal combustion engine, wherein the engine data processor (1) is configured: - to receive a geometric characteristic (10) of a discharge unit (11) through which the exhaust gas composition (25) can be discharged, and to determine a smoke visibility limit value (21,3) therefrom, - to receive filter fill level information (20) relating to an exhaust gas filter (16) designed to filter the exhaust gas composition (25), - to receive an average catalytic converter temperature (22) of an exhaust gas catalytic converter (18) designed to catalyse the exhaust gas composition (25), and to determine a nitrogen dioxide conversion rate (12) on the basis of the filter fill level information (20) and the average catalytic converter temperature (22), - to compare the nitrogen dioxide conversion rate (12) and the smoke visibility limit value (21,3) with each other, and to determine a manipulated variable (5) for the internal combustion engine therefrom such that the exhaust gas composition (25) is invisible, and - to output the manipulated variable (5).

2. Engine data processor (1) according to Claim 1, wherein the engine data processor (1) is configured: - to calculate a series (28) of nitrogen dioxide conversion rates (12) on the basis of the filter fill level information (20), and - to determine the nitrogen dioxide conversion rate (12) from the series (28) on the basis of the average catalytic converter temperature (22).

3. Engine data processor (1) according to Claim 1 or 2, wherein the engine data processor (1) is configured to receive a nitrogen oxide emission value (9) captured at the discharge unit (11) and a discharge unit pressure value (13) and to determine the smoke visibility limit value (21) therefrom.

4. Engine data processor (1) according to Claim 3, wherein the engine data processor (1) is configured to receive a filter pressure value (14) and to determine the filter fill level information (20) from the discharge unit pressure value (13) and the filter pressure value (14).

5. Engine data processor (1) according to one of the preceding claims, wherein the engine data processor (1) is configured to receive a filter temperature (15) and a catalytic converter temperature (17) and to determine the average catalytic converter temperature (22) therefrom.

6. Engine data processor (1) according to one of the preceding claims for suppressing yellow smoke (2), wherein the engine data processor (1) is configured: - to determine at least one smoke visibility limit value (21) in the form of a yellow smoke visibility limit value (3), - to determine the manipulated variable (5) in such a way that the production of visible yellow smoke (2) is suppressed.

7. Engine data processor (1) according to one of the preceding claims, comprising a conversion computing unit (32) which is configured to calculate a series (28) of increased or reduced nitrogen dioxide conversion rates (12) on the basis of the filter fill level information (20) .

8. Engine data processor (1) according to one of the preceding claims, comprising a model-predictive controller (35), wherein the model-predictive controller (35) comprises a limiting unit (41) which is configured to receive the nitrogen dioxide conversion rate (12) and the smoke visibility limit value (21) and to use them to create an operating limit (34) for setting an invisible exhaust gas composition (25) for the internal combustion engine.

9. Internal combustion engine (30) comprising an engine data processor (1) according to one of the preceding claims, an engine (19) for providing a mechanical power (43) and an exhaust gas aftertreatment system (42) comprising the exhaust gas catalytic converter (18) and the exhaust gas filter (16).

10. Internal combustion engine (30) according to Claim 9, wherein the model-predictive controller (35) is configured to derive from the operating limit (34) operationally optimal controller specifications (38) for setting the average catalytic converter temperature (22).

11. Internal combustion engine (30) according to Claim 10, comprising an actuator controller (37) which is configured to receive the operationally optimal controller specifications (38) and to determine the manipulated variable (5) for an actuation group (29) of the engine (19).

12. Computer-implemented method (100) for setting a filtered and catalysed exhaust gas composition (25) at a discharge unit (11) of an internal combustion engine (30), comprising the following steps: Step 101: receiving a geometric characteristic (10) of the discharge unit (11), Step 102: determining a smoke visibility limit value (21) from the geometric characteristic (11), Step 103: receiving an average catalytic converter temperature (22) and filter fill level information (20), and determining a nitrogen dioxide conversion rate (12) on the basis of the catalytic converter temperature (17) and the filter fill level information (20), Step 104: comparing the determined smoke visibility limit value (21) with the nitrogen dioxide conversion rate (12), and Step 105: determining a manipulated variable (5) that is used to operate the internal combustion engine (30) in such a way that the exhaust gas composition (25) to be discharged at the discharge unit (11) is invisible.

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