Method, device and computer program product for determining emitted pollutant masses of hybrid drives

Abstract

The method, the device and the computer program product relate to the detection of pollutant masses, emitted with an exhaust gas mass flow (11a), of an internal combustion engine (1a) operated in a hybrid drive system (1) together with an additional drive machine (1b) and having an exhaust gas aftertreatment device (2), by means of an electronic control device (7). In the running hybrid operating mode of the hybrid drive system (1), a start request for the internal combustion engine (1a) is first determined and the operational readiness of an associated exhaust gas sensor (6) is checked. If the operational readiness of the exhaust gas sensor (6) is not indicated, the internal combustion engine (1a) is operated in a start-up operating phase with predefined reference operating parameters (VKM_R-Pmtr) while simultaneously compensating for deviating power demands on the hybrid drive system (1), solely by means of an additional drive machine (1b), wherein the pollutant masses (S1) emitted during said start-up operating phase are determined on the basis of an emission reference value (RW_Ems), which is representative of a pollutant content (11) in the exhaust gas mass flow (11a) of the start-up operating phase. As soon as the operational readiness of the at least one associated exhaust gas sensor (6) is indicated, the start-up operating phase is ended and the pollutant masses (S2) still emitted by the internal combustion engine (1a) are determined on the basis of the emission value (AS_Sig) provided by the exhaust gas sensor (6). In this way, the emitted pollutant masses are accurately determined advantageously and in a simple manner, wherein the accuracy is steadily increased by means of continuously updated emission reference values (RW_Ems).

Description

[0001] 202400606

[0002] 1

[0003] Description

[0004] Method, device and computer program product for determining emitted pollutant masses from hybrid drives

[0005] The invention relates generally to hybrid drive systems consisting of an internal combustion engine (ICE) with an exhaust aftertreatment system and an additional drive motor, which is usually an electric motor. Such drive configurations are used particularly in motor vehicles, but also, for example, in construction machinery. These systems are increasingly used to reduce the operating time of the ICE and thus its emissions into the environment.

[0006] Current and future legal requirements for limiting pollutant emissions from motor vehicles necessitate effective and reliable combustion control for the internal combustion engines used, with a view to reducing pollutant emissions, as well as exhaust aftertreatment. Without these, compliance with the required emission limits, especially for nitrogen oxides (NOx), ammonia (NH3), and hydrocarbons (C), is not possible according to the current state of the art. m H n ) and carbon monoxide (CO) is not possible.

[0007] Exhaust gas sensors, such as lambda sensors, NOx sensors, HC sensors, or particle sensors, are used to control and regulate the combustion processes of the internal combustion engine (ICE) and the exhaust aftertreatment system. These sensors detect one or more components of the exhaust gas directly or in relation to each other and can be located at several different positions in the exhaust system, upstream and / or downstream in the exhaust mass flow, or even within the exhaust aftertreatment system itself. Such exhaust gas sensors are not only used for the general optimization of emissions behavior but increasingly for the continuous monitoring of pollutant emissions throughout the entire life cycle, i.e., from the initial commissioning of the ICE until its final decommissioning. This so-called on-board monitoring (OBM) continuously provides measurement data for assessing the emissions behavior of the ICE and can, if necessary,They can also be used to assess legal compliance.

[0008] Both the individual components of the exhaust aftertreatment system and the exhaust gas sensors used require 202400606 for safe and efficient operation.

[0009] 2

[0010] Operation occurs at operating temperatures above certain activation thresholds. Below these activation thresholds, the exhaust aftertreatment system does not operate at the required conversion rate, and the exhaust gas sensors deliver faulty or no usable readings.

[0011] In the intended operation of hybrid drive systems, operating phases in which the internal combustion engine (ICE) is switched off are frequent and intentional. Such operating phases include, for example, coasting phases when driving downhill, so-called sailing phases in which the vehicle rolls due to inertia and does not require propulsion, or propulsion phases in which propulsion is provided solely by the additional drive motor, such as an electric motor. During extended operating phases with the ICE switched off, both the exhaust aftertreatment system and the exhaust gas sensors may cool below the activation temperature threshold.

[0012] On the other hand, such mixed operation often leads to unpredictable, short-term activation of the internal combustion engine (ICE). Such activations can be caused, for example, by the user (vehicle driver) requesting increased drive power, but also by a lack of energy for operating the additional drive motor, such as the electric motor, for instance, due to a depleted battery. However, the exhaust gas sensors and the exhaust aftertreatment system require a certain amount of time (warm-up time) to reach operating temperature above their respective activation thresholds and function reliably.

[0013] During this period between the activation of the internal combustion engine and exceeding the activation thresholds, pollutant emissions are increased, and, conversely, no usable measurement data from the exhaust gas sensors is available during this time. Consequently, significant emission components are sometimes overlooked or inaccurate when integrating the emission masses over the operating period, potentially leading to impermissible deviations when compared with externally measured "Real Driving Emissions" (RDE).

[0014] Existing approaches to compensate for this disadvantage of missing measurement data model emission behavior based on various available measurement or model parameters. Alternatively, emission behavior can be described as 202400606

[0015] A constant offset of 3 is assumed. This offset, like any modeling, requires worst-case data, since the assessment of the conformity of each individual system in ferry operation (RDE) is based on limit values ​​that must not be exceeded under any circumstances without this being detected and displayed by the on-board monitoring (false good detection). From this perspective and with worst-case data, due to the inaccuracy of these two approaches, a system may be identified as non-compliant even though it is still compliant with the requirements when assessed using an external, continuously operating measurement system (RDE measurement) (false bad detection).

[0016] The present invention therefore aims to provide a method that enables a more accurate and thus more realistic and reliable determination of pollutant emission masses from an internal combustion engine equipped with an exhaust aftertreatment device during intended operation in a hybrid drive system. Furthermore, a control device and a computer program for carrying out the method are to be provided.

[0017] This task is solved by a method, an electronic control device, and a computer program for determining the mass of pollutants emitted with an exhaust gas mass flow from an internal combustion engine operated in a hybrid drive system together with an additional drive motor. Within the scope of this patent application, the determination, storage, summation, etc., of the emitted pollutant masses essentially refers to the determination, storage, summation, etc., of values ​​or pollutant mass values ​​that represent the mass of the emitted pollutants.

[0018] Advantageous embodiments, further developments and details of the present invention will become apparent from the dependent claims, the description and the drawing.

[0019] According to the invention, the internal combustion engine is equipped with an exhaust aftertreatment device and at least one exhaust gas sensor associated with the exhaust aftertreatment device for providing an emission value, wherein the emission value is representative for 202400606

[0020] 4. At least one pollutant content in the exhaust gas mass flow. To determine the emitted masses of different pollutants, several exhaust gas sensors can be installed, for example, which provide emission values ​​that are representative of the respective pollutant content. Exhaust gas sensors that provide multiple emission values ​​or total emission values ​​can also be used.

[0021] The method comprises the following process steps, which can be carried out with the electronic control device based on the computer program product according to the invention.

[0022] First, when the hybrid drive system is started or in an ongoing hybrid operating mode and the internal combustion engine is switched off, it is determined whether there is a start request for the internal combustion engine. If a start request is detected, the operational readiness of at least one associated exhaust gas sensor is checked and monitored.

[0023] If and as long as it is indicated that the operational readiness of at least one assigned exhaust gas sensor is not present, the internal combustion engine is started and operated in a start-up phase with predefined reference operating parameters. During this start-up phase, any power demands on the hybrid drive system that would require a deviation from the operation of the internal combustion engine with the predefined reference operating parameters—that is, demands that would require a deviation from the reference operating parameters in regular hybrid operating mode—are compensated solely by the additional drive motor.

[0024] The determination of the pollutant masses emitted by the internal combustion engine during this start-up operating phase is based on at least one emission reference value that is representative of at least one pollutant content in the exhaust gas mass flow during the start-up operating phase with predefined reference operating parameters. To determine the emission masses of various pollutants contained in the exhaust gas mass flow, respective assigned emission reference values ​​can be used. 202400606

[0025] 5

[0026] As soon as and as long as the monitoring of the operational readiness of the at least one assigned exhaust gas sensor indicates that the operational readiness of the at least one assigned exhaust gas sensor is given, the start-up operating phase is ended and the internal combustion engine continues to operate in hybrid operating mode, whereby the pollutant masses emitted by the internal combustion engine are determined on the basis of the emission value provided by the at least one exhaust gas sensor.

[0027] Ending the start-up phase means that the internal combustion engine is no longer operated constantly with the specified reference operating parameters, but with operating parameters of the internal combustion engine that are adapted to the power requirements of the hybrid drive system and may change dynamically.

[0028] The advantages of the invention essentially lie in the fact that the pollutant masses emitted during the intended operation of the internal combustion engine within the hybrid drive system can be reliably determined for all operating phases and used to assess exhaust emission behavior within the framework of legal regulations. The increased accuracy reduces the risk of false positive or premature negative detection.

[0029] In one embodiment of the method, at least one emission reference value is determined in preceding adaptation operating phases, given the operational readiness of at least one associated exhaust gas sensor, based on the emission value provided by the exhaust gas sensor, and continuously updated and stored during operation. During these adaptation operating phases, the internal combustion engine operates with the same predefined reference operating parameters, while simultaneously compensating for any deviating power requirements for the hybrid drive system (1), which would also necessitate a deviation from the operation of the internal combustion engine (1a) with the reference operating parameters (VKM_R-Pmtr), solely by means of the additional drive motor (1b). Naturally, the corresponding pollutant masses emitted during these adaptation operating phases are recorded simultaneously.Pollutant mass values, representing the emitted pollutant masses, are determined. The advantages of this design lie in the fact that the 202400606.

[0030] 6

[0031] The determination of emitted pollutant masses is dynamically adapted to the current operating conditions and thus carried out with further increased accuracy.

[0032] Since the exhaust gas sensor is already operational at the beginning of the adaptation phase, this phase continues for a predetermined duration. This predetermined adaptation duration can, for example, be the typical time required to bring the exhaust gas sensor to operational readiness, particularly to heat it up to an activation temperature. However, the adaptation duration can also be determined based on the specific thermal state of the exhaust aftertreatment system. In particular, certain characteristics of previous driving cycles, such as the distance traveled, the power profile of the internal combustion engine, or local minimum temperatures of the exhaust aftertreatment system, can also be used to determine the adaptation duration.

[0033] The initiation or execution of an adaptation operating phase can depend on certain adaptation prerequisites. These prerequisites can include specific typical or atypical operating conditions of the hybrid drive system, such as low, medium, or high drive loads, operating temperatures, energy storage charge levels (especially for the auxiliary drive motor), or environmental parameters such as ambient temperature, humidity, and air pressure. Adaptation operating phases can also simply occur at recurring intervals during the operation of the hybrid drive system.

[0034] In a further development of the above-described design, it is possible to add up the determined emitted pollutant masses, or the values ​​representing the emitted pollutant masses, or to integrate them over the operating time of the internal combustion engine to obtain a total pollutant mass emitted by the internal combustion engine over an operating cycle. The respective operating cycle can be defined, for example, by a number of operating hours, a distance traveled, or the entire service life of the internal combustion engine. The corresponding total pollutant mass can then advantageously be allocated to the distance traveled over the operating cycle by the vehicle powered by the hybrid drive system.

[0035] 7

[0036] vehicle-related data can be used to assess conformity with current pollutant emission legislation.

[0037] In a further embodiment, it can be provided that at least one emission reference value is determined, stored, and dynamically made available for determining the pollutant masses emitted during the start-up phase, depending on at least one additional parameter that can influence the pollutant fraction in the exhaust gas mass flow and / or the heating behavior of the exhaust aftertreatment device. Dynamic in this context means that the emission reference value changes with the changing additional parameter and is retrieved and made available for determining the emitted pollutant masses according to the currently available additional parameter. This advantageously allows for a further increase in the accuracy of determining the emitted pollutant masses.

[0038] In a further development of the previously described design, at least one of the additional parameters can be representative of the thermal state of the exhaust aftertreatment device, which can influence a pollutant fraction in the exhaust mass flow. The thermal state can be continuously determined based on temperature models or by means of a temperature sensor. This advantageously allows the emission reference value to be adjusted, for example, to the conversion rate of a catalyst installed in the exhaust aftertreatment device, which varies with the operating temperature.

[0039] In a further development of the two previously described embodiments, the current ambient temperature of the internal combustion engine (1a) and / or the current humidity of an air mass drawn in by the internal combustion engine (1a) can be used as additional parameters. This allows, for example, ambient conditions that can influence the pollutant emission behavior of the internal combustion engine to be taken into account when determining the emitted pollutant masses.

[0040] Another embodiment of the invention provides that, based on the reference operating parameters, the thermal states of the exhaust aftertreatment device and the at least one exhaust gas sensor at the start of the internal combustion engine, as well as at least one additional parameter, a maximum time duration from the start of the internal combustion engine until 202400606

[0041] 8

[0042] The system estimates when at least one assigned exhaust gas sensor will reach operational readiness. Based on this maximum time and at least one emission reference value, the pollutant masses emitted by the internal combustion engine within this maximum time period are determined and added to a total pollutant mass accumulated over the engine's operating time. Once the determined maximum time period has elapsed, the system indicates when the at least one exhaust gas sensor is operational. In this way, a defined time period is specified for which the emission reference value is determined to calculate the emitted pollutant mass for the period during which the exhaust gas sensor is not operational.

[0043] A further embodiment of one of the aforementioned embodiments of the invention is characterized in that the exhaust gas sensor provides emission values ​​that are representative of at least one of the pollutants from the group consisting of nitrogen oxides (NOx), hydrocarbons (HnCm), carbon oxides (COx), ammonia (NH3), soot particles, or particulate matter. This advantageously enables the determination of all relevant pollutant emissions from an internal combustion engine.

[0044] The electronic control device according to the invention for operating a hybrid drive system with an internal combustion engine with exhaust aftertreatment device and an additional drive motor comprises at least one electronic storage device in which at least one computer program product with program instructions is provided, and an input / output interface configured for receiving and outputting electrical signals, as well as an electronic processing unit for executing the program instructions, with access to the at least one electronic storage device and the input / output interface. When executed by the electronic processing unit, the program instructions cause the electronic control device to execute the method according to one of the embodiments described above.The electronic control device can be designed as a standalone unit or as an integral component of a higher-level central control unit for the hybrid drive system. 202400606.

[0045] 9

[0046] The advantages of the electronic control device according to the invention correspond to the advantages offered by the described method according to the invention.

[0047] The computer program product according to the invention for operating a hybrid drive system with an internal combustion engine with exhaust aftertreatment device and an additional drive motor comprises program instructions for execution by the electronic computing unit of the previously described electronic control device, wherein the program instructions, when executed by the electronic computing unit, cause the electronic control device to carry out the method according to the invention in accordance with one of the previously described embodiments.

[0048] The features and combinations of features of the embodiments of the invention described above or described below in the figure descriptions are to be applied individually, partially, or in their entirety, including in combination or complementary form, in further developments of the invention, without departing from the scope of the invention, provided they are not alternatively applicable or mutually exclusive. Features and details described in connection with the method naturally also apply in connection with the electronic control device and the computer program product, and vice versa, so that mutual reference can always be made to the individual aspects of the invention with regard to the disclosure of this invention.

[0049] The figures below illustrate particularly advantageous embodiments, details or further developments of the invention, although the subject matter of the invention is not limited to these examples.

[0050] They show:

[0051] Fig. 1 is a simplified flowchart illustrating the procedure 202400606

[0052] 10

[0053] Fig. 2 shows a simplified schematic representation of a hybrid drive system with an internal combustion engine, exhaust aftertreatment device and an additional drive motor.

[0054] The figures in this application are to be considered schematic only, and the relative sizes of the individual figures and the elements depicted within them are not to scale. Rather, individual elements may be exaggerated for clarity and / or to improve comprehensibility. Elements with identical functions, names, or similar effects are identified across all figures by the same reference symbols. In some figures, individual reference symbols may be omitted to improve clarity.

[0055] Figure 1 shows a highly simplified example of the process flow of an embodiment of the method according to the invention, depicted in individual process steps. The method is carried out by means of an electronic control device 7 associated with the hybrid drive system and / or the internal combustion engine 1 and / or the exhaust aftertreatment device 2. However, the method according to the invention and its described embodiments are not to be interpreted as being limited to the process steps and relationships shown in Figure 1. Rather, the illustrated method represents an embodiment in an advanced stage of development, which nevertheless contains the fundamental process steps as a basis.

[0056] The process step VS_1 shown in Fig. 1 represents the ongoing hybrid operating mode or also a rest mode of the hybrid drive system 1 with the internal combustion engine 1 a switched off.

[0057] In the subsequent decision step ES_1, it is monitored and determined whether a start request exists for the internal combustion engine 1a. As long as no start request exists, the system returns to the decision path marked "no," and the hybrid drive system 1 continues to operate with the internal combustion engine 1a switched off, or remains in standby mode. However, if a start request is detected, the process step VS_2 is called via the decision path marked "yes."

[0058] In process step VS_2 and the subsequent decision step ES_2, the operational readiness of at least 202400606 is checked and monitored.

[0059] 11 an assigned exhaust gas sensor 6. If, in decision step ES_2, it is determined that the operational readiness of at least one assigned exhaust gas sensor 6 is not indicated, the decision path marked "no" leads to process step VS_3, and the internal combustion engine 1a is started and operated in a start-up operating phase with predefined reference operating parameters VKM_R-Pmtr, while simultaneously compensating for power requirements on the hybrid drive system 1 that would require a deviation from the operation of the internal combustion engine 1a with the reference operating parameters VKM_R-Pmtr, solely by means of the additional drive motor 1b. The reference operating parameters VKM_R-Pmtr are retrieved, for example, from the operating data memory 7b2 of the electronic control device 7, represented by the dashed block marked VKM_R-Pmtr.

[0060] During the ongoing start-up phase, the pollutant masses S1 emitted by the internal combustion engine 1a during this start-up phase are determined, represented by process step VS_4. This determination is based on at least one emission reference value RW_Ems, which is representative of at least one pollutant content in the exhaust gas mass flow 11a of the start-up phase with predefined reference operating parameters VKM_R-Pmtr. The at least one emission reference value RW_Ems is also retrieved, for example, from the operating data memory 7b2 of the electronic control device 7, represented by the dashed block labeled RW_Ems. The emitted pollutant masses, or the corresponding pollutant mass values ​​S1, are then output.The pollutant masses are provided, identified by the arrow labeled S1, and added or integrated with the other determined pollutant masses to form a total pollutant mass S_GM in a designated storage area, preferably in the operating data memory 7b2 of the electronic control device 7. This is symbolically represented by the storage block labeled S_GM.

[0061] In decision step ES_3, it is monitored whether the operational readiness of at least one assigned exhaust gas sensor 6 is indicated. If this is not the case, the start-up operating phase continues with predefined reference operating parameters VKM_R-Pmtr, which is indicated by the 202400606

[0062] 12

[0063] The return to process step VS_3 is shown via the decision path marked "no".

[0064] However, as soon as and as long as the operational readiness of at least one assigned exhaust gas sensor 6 is indicated, the start-up operating phase is terminated and the internal combustion engine 1a continues to operate in the intended hybrid operating mode, as represented by process step VS_5. During the operation of the internal combustion engine 1a in the intended hybrid operating mode, the pollutant masses S2 emitted by the internal combustion engine 1a are then determined based on the emission value AS_Sig provided by the exhaust gas sensor 6. The provision of the emission value AS_Sig is symbolized in Fig. 1 by the dashed block labeled AS_Sig. The pollutant masses emitted in this operating phase, or the corresponding pollutant mass values ​​S2, are then output.provided, characterized by the arrow marked S2, and in a storage area provided for this purpose, preferably in the operating data storage 7b2 of the electronic control device 7, together with the other determined pollutant masses, added or integrated to a total pollutant mass S_GM, as already described above.

[0065] Process step VS_6 then marks the switching off of the internal combustion engine 1 a and there is a jump back to the beginning of the process at process step VS_1.

[0066] However, if in decision step ES_2 it is determined that the operational readiness of at least one assigned exhaust gas sensor 6 is indicated, the process proceeds via the decision path marked "yes" to the further decision step ES_2.1, in which it is checked whether certain adaptation prerequisites are met. If these adaptation prerequisites are not met, the process proceeds directly via the decision path marked "no" to the process step VS_5, which represents the intended hybrid operating mode of the internal combustion engine 1a, as already described above.

[0067] However, if it is determined in decision step ES_2.1 that the specific adaptation prerequisites are met, an adaptation operational phase is initiated via the decision path marked "yes". In the adaptation operational phase, represented by process step VS_3.1, the 202400606

[0068] 13

[0069] Internal combustion engine 1 a with the same specified reference operating parameters VKM_R-Pmtr while simultaneously compensating for power requirements to the hybrid drive system 1 which would require a deviation from the operation of the internal combustion engine 1 a with the reference operating parameters VKM_R-Pmtr, is operated solely by means of the additional drive engine 1 b.

[0070] However, as shown in process step VS_4.1, the pollutant masses, or rather the pollutant mass values ​​S3, are determined here, given the operational readiness of the exhaust gas sensor 6, based on the emission value AS_Sig provided by the exhaust gas sensor 6. This is illustrated by the dashed arrow that originates from the block labeled AS_Sig and ends in process step VS_4.1.

[0071] The pollutant mass values ​​determined in this way are then provided as emission reference values ​​RW_Ems and continuously updated and stored during operation, for example in the operating data storage 7b2 of the electronic control device 7, where they are available for retrieval for the start-up operating phase according to procedure step VS_4.

[0072] Naturally, the pollutant mass values ​​S3 determined during the adaptation operating phase are also output or made available, indicated by the arrow marked S3, and added or integrated together with the other determined pollutant masses to a total pollutant mass S_GM in a storage area provided for this purpose, preferably in the operating data memory 7b2 of the electronic control device 7, as described above.

[0073] The at least one emission reference value RW_Ems can be determined in process step VS_4.1 as a function of at least one additional parameter Z_Pmtr, which can influence the pollutant fraction in the exhaust gas mass flow 11 a and / or the heating behavior of the exhaust gas aftertreatment device 2. This emission reference value RW_Ems is then also stored as a function of the at least one additional parameter Z_Pmtr and dynamically provided to determine the pollutant mass values ​​S1 emitted during the start-up operating phase as a function of the at least one current additional parameter Z_Pmtr. 202400606

[0074] 14

[0075] This is shown in Fig. 1 by the dashed block labelled Z_Pmtr.

[0076] In the decision step ES_4, which follows process step VS_4.1, it is monitored and determined whether the adaptation operating time specified for the adaptation operating phase has expired. As long as this is not the case, the internal combustion engine 1a continues to operate in the adaptation operating phase, as can be seen from the return to process step VS_3.1 via the decision path marked "no".

[0077] However, if it is determined in decision step ES_4 that the specified adaptation operating time has expired, the procedure is continued in the previously described procedure step VS_5 until the internal combustion engine 1 a is switched off in procedure step VS_6.

[0078] Figure 2 shows a hybrid drive system 1 with an internal combustion engine 1a and an additional drive machine 1b. The additional drive machine 1b is, for example, an electric machine, in particular an electric motor, which, as shown here, is coupled to the internal combustion engine 1a. However, the additional drive machine 1b can also be arranged at another point in a drive train common with the internal combustion engine 1a (not shown). For control purposes, the additional drive machine 1b is connected to the electronic control device 7 via at least one signal line 8.

[0079] The internal combustion engine 1a can, for example, be designed as a reciprocating piston engine with four cylinders (indicated). The internal combustion engine 1a is supplied with air-fuel mixture 10a from the intake side via an air-fuel mixture supply unit 10. The air-fuel mixture supply unit 10 represents, for example, a fuel injection system in conjunction with a throttle valve, which is connected to the electronic control device 7 via signal lines 8 and is controlled in such a way that an air-fuel mixture 10a is supplied to the combustion chambers of the internal combustion engine 1 in a predetermined quantity and composition. Thus, the electronic control device can influence both the available power and the composition of the exhaust gas flow 11a, according to the program instructions contained therein.

[0080] 15 in particular the so-called lambda value, which provides information about the oxygen content in the exhaust gas stream 11 a.

[0081] An exhaust aftertreatment device 2 is connected to the exhaust side of the internal combustion engine 1. This device comprises a first exhaust catalyst 3, a second exhaust catalyst 4, and a particulate filter 5, which are connected to the internal combustion engine 1 via an exhaust pipe 11 and interconnected. This exhaust aftertreatment device 2 corresponds to a conventional design in a gasoline internal combustion engine, but this configuration is not strictly necessary for carrying out the method according to the invention. It is explicitly noted that the methods and components according to the invention can also be used with different configurations of internal combustion engines and exhaust aftertreatment devices, such as those used, for example, in diesel internal combustion engines.Of particular importance, however, is the exhaust gas sensor 6 at the outlet of the exhaust gas aftertreatment device 2, through which the exhaust gas flow 11a is released into the environment after aftertreatment has taken place.

[0082] The exhaust gas flow 11a is directed through the exhaust pipe 11 to the aforementioned components of the exhaust aftertreatment device 2. The exhaust gas flow 11a is represented by arrow symbols indicating the direction of flow. The first exhaust catalyst 3 is located close to the engine, directly at the exhaust outlet of the internal combustion engine 1, and is designed, for example, as a three-way catalyst (TWC). Downstream of the first exhaust catalyst 3, with respect to the exhaust gas flow 11a, is a particulate filter 5, which is designed, for example, as a gasoline particulate filter (GPF), followed by the second exhaust catalyst 4, which can also be designed as a three-way catalyst (TWC) and can, for example, be arranged as a so-called underbody catalyst (UBC) on the underbody of a motor vehicle.

[0083] In the exhaust pipe 11, a first exhaust gas sensor 6a is arranged upstream of the first exhaust gas catalyst 3, a second exhaust gas sensor 6b is arranged downstream of the first exhaust gas catalyst 3, and a third exhaust gas sensor 6 is arranged downstream of the second exhaust gas catalyst 4 in the exhaust gas stream 11a. Additionally, a temperature sensor 9 for measuring the temperature of the exhaust gas stream 11a is arranged in the exhaust pipe 11 between the first exhaust gas catalyst 3 and the particulate filter 5. 202400606

[0084] 16 arranged. The pressure drop across the particle filter 5, which provides information about the soot loading of the particle filter 5, is determined by means of a differential pressure sensor Ap.

[0085] The sensors 6, 6a, 6b and 9 mentioned above are connected via electrical signal lines 8 to the input / output interface 7c of an electronic control device 7 according to the invention for transmitting the sensor signals to the control device 7. The air-fuel mixture supply unit 10 of the internal combustion engine 1 and the additional drive motor 1b are also connected via electrical signal lines 8 to the input / output interface 7c of the electronic control device 7 according to the invention.

[0086] The electronic control device 7 sketched here as an example comprises an electronic computing unit 7a, also referred to as a processor, an electronic storage device 7b, and an input / output interface 7c. In this embodiment, the electronic storage device 7b includes a program memory 7b1 in which a computer program product 20 according to the invention, containing program instructions, is available. Furthermore, the electronic storage device 7b includes an operating data memory 7b2 in which predefined operating data 21, as well as data acquired during operation, can be stored, for example, arranged in characteristic maps. A portion of this operating data memory 7b2 can also be used, for example, as an error memory.

[0087] However, within the scope of the invention, different architectures of the electronic control device 7 are also possible, as long as the functionalities required for carrying out the method are provided.

[0088] The electronic computing unit 7a is configured to carry out the method according to the invention in the embodiments described above and, if applicable, in addition thereto. For this purpose, the electronic computing unit 7a has access to, or is in a data connection (symbolized by connecting arrows) with, the input / output interface 7c, the program memory 7b1, and the operating data memory 7b2. When executing the program instructions, the electronic computing unit 7a uses the relevant operating parameters, for example, the reference operating parameters VKM_R-Pmtr and the emission reference value RW_Ems, as well as, if applicable, various other threshold values ​​for, e.g., pollutant emission masses, emission comparison values ​​202400606.

[0089] 17 or emission ratio values ​​from pollutant emission mass and distance traveled, the electronic control device 7 is prompted to execute the inventive method for determining pollutant masses emitted with an exhaust gas mass flow 11 a of the internal combustion engine 1 a operated in the hybrid drive system 1 together with an additional drive engine 1 b, optionally with simultaneous execution of a lambda control of the fuel-air mixture 10a supplied to the internal combustion engine 1 a during operation.

[0090] In accordance with the program instructions, sensor data or operating parameters, such as the AS_Sig signal from the exhaust gas sensor 6, which represents the pollutant content and / or the oxygen content in the exhaust gas stream 11a, and signals from the temperature sensor 9, are received via the input / output interface 7c and, if necessary, stored as operating data 21 in the operating data memory 7b2. The program then executes the calculations specified for operating and on-board diagnostics of an exhaust gas control system of an internal combustion engine 1 according to the method according to the invention. Based on this, control commands, for example, for controlling the air-fuel mixture 10a, are then output to the air-fuel mixture supply unit 10 of the internal combustion engine 1.

[0091] For the execution of the method, the sensor signal values, AS_Sig, provided by the exhaust gas sensor 6 and representative of the concentration of at least one pollutant in the exhaust gas stream 11a of the internal combustion engine 1a released into the environment are used in particular. The sensor signal values ​​AS_Sig provided by at least one exhaust gas sensor 6 can, for example, be representative of a total pollutant concentration of NOx and NH3 in the exhaust gas stream 11a of the internal combustion engine 1 leaving the exhaust aftertreatment device 2. 202400606

[0092] 18

[0093] Reference symbol list

[0094] 1 Hybrid drive system

[0095] 1a Internal combustion engine

[0096] 1 b Additional drive motor

[0097] 2 Exhaust aftertreatment device

[0098] 3 first exhaust catalyst

[0099] 4 second exhaust catalyst

[0100] 5 particle filters

[0101] 6 Exhaust gas sensor

[0102] 6a - b further exhaust gas sensors

[0103] 7 electronic control device

[0104] 7a Electronic computing unit

[0105] 7b Electronic storage device

[0106] 7b1 Program memory

[0107] 7b2 Operational data storage

[0108] 7c Input / Output Interface

[0109] 8 signal lines

[0110] 9 Temperature sensor

[0111] 10 Air-fuel mixture supply unit

[0112] 10a Air-fuel mixture

[0113] 11 Exhaust pipe

[0114] 11a Exhaust gas mass flow

[0115] 20 computer program product

[0116] 21 Operational data

[0117] GPF Gasoline Particulate Filter

[0118] Ap differential pressure sensor

[0119] TWC three-way catalytic converter

[0120] UbKat underfloor catalytic converter

[0121] VS_1-6 Procedure steps

[0122] ES_1-4 Decision Steps

[0123] AS_Sig emission value of the exhaust gas sensor

[0124] VKM internal combustion engine VKM_R-Pmtr Reference operating parameter of the internal combustion engine RW Ems Emissions reference value

[0125] Z_Pmtr Additional parameters

[0126] S1-3 Pollutant masses / pollutant mass values

[0127] S_GM Total pollutant mass

Claims

1. 202400606 19 Patent claims 1. Method for determining pollutant masses emitted with an exhaust gas mass flow (11a) from an internal combustion engine (1a) operated in a hybrid drive system (1) together with an additional drive engine (1b), by means of an electronic control device (7), wherein the internal combustion engine (1) is equipped with an exhaust gas aftertreatment device (2) and at least one exhaust gas sensor (6) associated with the exhaust gas aftertreatment device (2) for providing an emission value that is representative of at least one pollutant content in the exhaust gas mass flow (11a), wherein the method comprises the following process steps that can be carried out with the electronic control device (7): When the hybrid drive system (1) is started or in a running hybrid operating mode and the internal combustion engine (1a) is switched off, detect a start request for the internal combustion engine (1a); Check and monitor the operational readiness of the at least one assigned exhaust gas sensor (6), if and as long as operational readiness of the at least one assigned exhaust gas sensor (6) is not indicated, start and operate the internal combustion engine (1 a) in a start-up operating phase with predefined reference operating parameters (VKM_R-Pmtr) while simultaneously compensating for power requirements on the hybrid drive system (1) that would require a deviation from the operation of the internal combustion engine (1 a) with the reference operating parameters (VKM_R-Pmtr), solely by means of the additional drive motor (1 b) and determine the pollutant masses (S1 ) emitted by the internal combustion engine (1 a) during this start-up operating phase based on at least one emission reference value (RW_Ems),which is representative for at least one pollutant content in the exhaust gas mass flow (11 a) of the start-up operating phase with specified reference operating parameters (VKM_R-Pmtr) as soon as and as long as operational readiness of the at least one associated exhaust gas sensor (6) is indicated, 202400606 20. End the start-up operating phase and continue operating the internal combustion engine (1 a) in hybrid operating mode and determine the pollutant masses (S2) emitted by the internal combustion engine (1 a) based on the emission value (AS_Sig) provided by the exhaust gas sensor (6).

2. Method according to claim 1, wherein the at least one emission reference value (RW_Ems) is determined in preceding adaptation operating phases with the same predetermined reference operating parameters (VKM_R-Pmtr) while simultaneously compensating for power requirements on the hybrid drive system (1) that would require a deviation from the operation of the internal combustion engine (1a) with the reference operating parameters (VKM_R-Pmtr), solely by means of the additional drive machine (1b), but with the at least one associated exhaust gas sensor (6) being operationally ready, based on the emission value (AS-Sig) provided by the exhaust gas sensor (6) and continuously updated and stored during operation, wherein the associated pollutant masses (S3) emitted in these adaptation operating phases are simultaneously determined.

3. Method according to claim 1 or 2, wherein the determined emitted pollutant masses (S1 , S2, S3) are added to a total pollutant mass (S_GM) emitted by the internal combustion engine (1 a) over one operating cycle.

4. Method according to claim 3, wherein the at least one emission reference value (RW_Ems) is determined, stored and dynamically provided as a function of at least one additional parameter (Z_Pmtr) which can influence the pollutant content in the exhaust gas mass flow (11 a) and / or the heating behavior of the exhaust gas aftertreatment device (2).

5. Method according to claim 4, wherein at least one of the additional parameters (Z_Pmtr) is representative of the thermal state of the exhaust aftertreatment device (2) and / or of characteristics of preceding driving cycles that can influence a pollutant fraction in the exhaust mass flow (11a). 202400606 21 6. Method according to claim 4 or 5, wherein at least one of the values ​​of a current ambient temperature of the internal combustion engine (1a) or a current humidity of an air mass drawn in by the internal combustion engine (1a) is used as an additional parameter or as a further additional parameter (Z_Pmtr).

7. Method according to claims 1 to 6, wherein, based on the reference operating parameters (VKM_R-Pmtr), the thermal states of the exhaust aftertreatment device (2) and the at least one exhaust gas sensor (6) at the start of the internal combustion engine (1a), as well as at least one additional parameter (Z_Pmtr), a maximum time period from the start of the internal combustion engine (1a) until the operational readiness of the at least one associated exhaust gas sensor (6) is estimated, and based on this maximum time period and the at least one emission reference value (RW_Ems), the pollutant masses emitted by the internal combustion engine (1a) within the maximum time period are determined and added to a respective total pollutant mass summed over the operating time of the internal combustion engine (1a), wherein, after the expiry of the determined maximum time period, the operational readiness of the at least one exhaust gas sensor (6) is indicated.

8. Method according to any one of claims 1 to 7, wherein the exhaust gas sensor provides emission values ​​(AS_Sig) that are representative of at least one of the pollutants from the group consisting of nitrogen oxides, NOx, hydrocarbons, HnCm, carbon oxides COx or ammonia, NH3, or soot particles or particulate matter.

9. Electronic control device (7) for operating a hybrid drive system (1) with an internal combustion engine (1a) with exhaust aftertreatment device (2) and an additional drive engine (1b), with at least one electronic storage device (7b) in which at least one computer program product (20) with program instructions is provided and an input / output interface (7c) which is configured for receiving and outputting electrical signals, as well as 202400606 22 an electronic computing unit (7a) for performing the Program instructions, with access to the at least one electronic storage device (7b) and the input / output interface (7c); wherein the program instructions, when executed by means of the electronic computing unit (7a), cause the electronic control device (7) to execute the method according to one of the preceding claims.

10. Computer program product (20) for operating a hybrid drive system (1 ) with an internal combustion engine (1 a) with exhaust aftertreatment device (2) and an additional drive motor (1b), comprising program instructions for execution by the electronic computing unit (7a) of the electronic control device (7) according to claim 9, wherein the program instructions, when executed by the electronic computing unit (7a), cause the electronic control device (7) to carry out the method according to any one of claims 1 to 8.

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