Method for aftertreatment of exhaust gases in a hybrid machine

Abstract

The invention relates to a method for exhaust gas aftertreatment in a hybrid machine having at least one electric motor (2) and an internal combustion engine (3), wherein the method comprises operating the hybrid machine in a first operating mode in which only the electric motor (2) is switched on and the internal combustion engine (3) is switched off; determining whether heating of an exhaust gas aftertreatment system (20) of the hybrid machine is required; and in the event that heating is required, at least temporarily switching on the internal combustion engine (3) in order to heat the exhaust gas aftertreatment system (20).

Description

Technical Field

[0001] The present invention relates to a method for after-treatment of exhaust gas in a hybrid machine, as well as a computing unit and a computer program for performing the method. Background Technology

[0002] Hybrid machines, such as hybrid vehicles, which are referred to as "hybrid engines" by definition, are equipped with an internal combustion engine and an electric drive.

[0003] During the initial engagement of a vehicle or machine, the electric motor is typically used first. Then, during further operation, in order to increase total power, reduce energy consumption, and / or increase effective range and operating duration, the internal combustion engine is at least partially engaged or operates in place of the electric drive.

[0004] The internal combustion engine used in a hybrid system produces combustion gases in accordance with the power requested by the engine, just like in a conventional machine. However, unlike in a conventional drive, the internal combustion engine in a hybrid system is not forced to start when the machine is stationary, but often starts during operation. Furthermore, it is generally true that the more power is requested, the greater the emissions from the motor.

[0005] What applies here is that emissions in actual driving operation (RDE, Real Driving Emissions) are often much higher than emissions obtained in a laboratory within a legally mandated testing period. These emissions are also managed for hybrids through prescribed RDE values, as in EU Regulation 2017 / 1154, scheduled for 7 June 2017. The objective, in principle, is to achieve similar emission values ​​in hybrids as in conventional drives, and at least comply with the limits of those emission values.

[0006] To comply with these emission limits, exhaust aftertreatment is required, as in conventional cases. However, exhaust aftertreatment systems require a certain operating temperature to ensure the necessary conversion of harmful gases to comply with managed emissions and operate optimally only within a specific temperature range. Therefore, it is advantageous for exhaust aftertreatment systems to heat up rapidly and not fall below their minimum operating temperature, even during operation.

[0007] Exhaust aftertreatment systems typically heat the exhaust stream; however, the flow of untreated hazardous substances can be extremely large and unacceptably high until the system reaches its operating temperature. This is particularly problematic in hybrid systems, where the internal combustion engine frequently and irregularly draws on high power from the electric drive at other times. When the internal combustion engine is temporarily engaged during operation based on required power, the exhaust aftertreatment system, which is not yet (or no longer) adequately heated at that point, may not be able to adequately convert the hazardous gases. This situation therefore requires significantly more effort for exhaust aftertreatment than in vehicles and machines with conventional drives. Summary of the Invention

[0008] According to the present invention, a method for exhaust aftertreatment in hybrid machines, particularly hybrid vehicles, is proposed, along with a computing unit and a computer program for performing the method. Advantageous designs are the subject of preferred embodiments and the following description.

[0009] This invention is based on a method in which the exhaust aftertreatment system of a hybrid machine with an electric motor and an internal combustion engine is checked to determine whether it needs to be heated in order to reduce emissions (including carbon dioxide), and the internal combustion engine is engaged, at least temporarily, during electric operation for heating purposes. This targeted engagement of the internal combustion engine allows the exhaust aftertreatment system to be prepared for the higher motor power required at a later point in time.

[0010] In one implementation, the need to heat the exhaust aftertreatment system can be determined based on an evaluation of measurement data, wherein the measurement data has been acquired at least in part during the operation of the hybrid engine to date and includes, for example, the temperature of the exhaust aftertreatment system, power data of the electric motor and / or the internal combustion engine, or values ​​related to the exhaust stream components.

[0011] Furthermore, determining whether a heated exhaust aftertreatment system is needed may include: forecasting future measurement data anticipated over a specific time period, wherein the forecast is calculated based on stored measurement data, which may be from past operation or vehicle data collected from other vehicles. The forecast may alternatively or additionally be based on data that determines the expected drive power required over a predetermined future time period. This data may include time, date, internal and external temperature and weather data (temperature, humidity, light intensity, precipitation, rolling resistance and slippage measurements of the vehicle's wheels), visual traffic sign recognition, accumulator ("battery") charging status, and forecasts (e.g., local weather forecasts). This data may also be, for example, navigation data, upon which road segment characteristics, speed limits, uphill sections, turns, and / or stopping points can be identified. This data may also be generated and calculated from current traffic conditions, such as measurements via spacing radar, and from anticipated traffic conditions on the approaching road segment, the traffic density of that segment, and average speeds (e.g., congestion forecasts). Current vehicle adjustments selected by the driver (especially so-called "driving modes," such as autonomous driving, semi-autonomous driving, driver assistance systems-supported modes, or purely manual driving, optimizing cost-effective, comfort-oriented, time-optimized, or dynamic driving) and driver characteristics based on historical data (especially driving dynamics such as acceleration characteristics, spacing characteristics, coasting and braking characteristics, especially even if these driving dynamics result in power consumption or energy recovery) and preferences regarding temperature control and air conditioning before and during vehicle operation (e.g., pre-cooling, or parking for heating) are further examples of measurements that can be used to predict future trends.

[0012] The application of the data mentioned and calculated is not necessarily limited to a single machine. Direct or indirect communication between two, a small number, or a large number of machines in a group or in multiple interconnected groups is advantageous. For the transmission, storage, and evaluation of this data for subsequent similar or other applications, it is advantageous to connect the machines to the Internet. During evaluation, according to one implementation, it is preferable to compare the measured and / or predicted measurement data with at least one predetermined threshold, and determine whether heating is required if the temperature is below or above said at least one predetermined threshold (e.g., the exhaust aftertreatment system temperature is too low). This ensures that the exhaust aftertreatment system is always maintained within the range of minimum or optimal operating temperatures, or at least at a determined minimum temperature from which it can be reheated sufficiently quickly.

[0013] In another implementation, the internal combustion engine is engaged at predetermined times and / or for predetermined durations. These times can be stored and followed individually, or in combination with other assessments and predictions. These predetermined times and / or predetermined durations of engagement can optionally be changed during operation based on stored or detected data. Such changes can be made once or stored as permanent changes.

[0014] In another implementation, at least a portion of the exhaust aftertreatment system can be electrically heated for a predetermined period of time before the internal combustion engine is turned on to heat the exhaust aftertreatment system. This allows the time during which the internal combustion engine must be turned on for heating to be kept short, or a very small amount of the engine's power to be utilized during this time.

[0015] It is also advantageous to implement the method according to the invention in the form of a computer program for performing all the method steps or a computer program product with program code, because this results in particularly low cost, especially when the implemented controller can also be used for other tasks and therefore already exists. Suitable data carriers for providing the computer program are, in particular, magnetic, optical, and electrical memories, such as hard disks, flash memory, EEPROM, DVDs, etc. The program can also be downloaded via computer networks (Internet, intranet, mobile wireless connection, etc.).

[0016] The computing unit according to the invention, such as a controller for a motor vehicle, is particularly configured in terms of programming technology to execute the method according to the invention.

[0017] The present invention is schematically illustrated in the accompanying drawings with reference to embodiments, and will be described more precisely below with reference to the accompanying drawings. Attached Figure Description

[0018] Figure 1 An exhaust aftertreatment system according to one embodiment of the present invention is illustrated schematically;

[0019] Figure 2 A flowchart of a commonly used method according to an embodiment of the present invention is illustrated by way of example; and

[0020] Figure 3 A flowchart illustrating the steps of an exemplary method according to an embodiment of the present invention is shown. Detailed Implementation

[0021] Figure 1An exemplary system, such as a vehicle, is schematically illustrated, in which the method according to the invention can be used. Here, the drive system 1, which combines an electric motor 2 and an internal combustion engine 3, operates as a hybrid. The exhaust gas from the internal combustion engine is directed to the exhaust aftertreatment system 20 via a piping system 22. Optionally, an electric heating device 24 may be present to heat a portion of the exhaust aftertreatment system.

[0022] The control unit 10 can be used to control motors 2 and 3 and also to regulate and monitor the operating temperature of the exhaust aftertreatment system 20 according to the present invention. Even though the control unit is shown here as the only module, multiple separate or connected modules with different tasks may be involved. A suitable storage device 11 is connected to the control unit.

[0023] For example, different sensors 31, 32, 33, and 34 can be installed on the exhaust aftertreatment system 20, on the motors 2 and 3, in the exhaust pipe 22, or in other suitable locations. The control device can read the data from the sensors or the data from the sensors can be transmitted to the control device from other parts.

[0024] exist Figure 2 The basic process of the method according to the invention is illustrated by way of example.

[0025] In the first embodiment of the hybrid machine, the hybrid motor first operates in electric drive mode in step 200, that is, only the electric motor 2 is used, and the internal combustion engine 3 is turned off. The control device 10 or other regulating device of the hybrid motor typically regulates when the internal combustion engine is engaged and for how long, for example, to increase drive power or save electrical energy.

[0026] In one embodiment, it is now additionally determined in step 210 whether heating the exhaust aftertreatment system 10 is necessary. If so, then in step 230, the internal combustion engine is turned on to heat the exhaust aftertreatment system. Optionally, component 220 may have been preheated by, for example, an electric heating device, as will be described in more detail below.

[0027] In a simplified implementation, for example, it can be determined that, in electric drive mode, the internal combustion engine is activated at predetermined time intervals for heating. The duration of the engine activation and the selected operating state for this purpose can also be predetermined, resulting in irregular or regular periodic activation. Alternatively, the internal combustion engine can operate for longer periods, with selectable power adjustments and correspondingly changeable operating states, until sustained activation (e.g., using predetermined power in the selected operating state), especially if the operating temperature required by the exhaust aftertreatment system cannot be reached. In this way, time rules can be determined and stored, according to which the internal combustion engine should be activated. The control device can repeatedly invoke these rules and accordingly initiate engine activation.

[0028] For example, in one implementation, it can be determined that, in electric drive mode, the internal combustion engine is engaged to heat the vehicle, and the power generated therein is used to propel the vehicle (or, correspondingly, to perform machine work, such as in agricultural or construction machinery), or to charge an electric storage device (“battery”). The internal combustion engine can here be particularly advantageous for heat removal, emission, and fuel consumption in connection with the exhaust aftertreatment system. This is especially true in situations where the power of the internal combustion engine is not to be used, or should not be primarily used, for machine work (e.g., for propulsion). The duration of the internal combustion engine engagement and the selected operating state for this purpose can also be predetermined, resulting in irregular or regular periodic engagement.

[0029] The control device can also determine whether heating and adjustment of the internal combustion engine are needed based on the measured or stored data, or it can also change the predetermined conditions for turning on the internal combustion engine during operation based on this data.

[0030] There are different possibilities for using data to assess and adjust the connection. Figure 3 It is shown in the form of another method diagram. Figure 2 The exemplary detailed process for determining step 210 is provided, wherein the steps are not necessarily all performed and are not necessarily performed in the order shown. Other method steps not shown in the figures may also occur. The described process illustrates only one possible implementation.

[0031] In step 310, the control device acquires the measurement data from the sensor. This data can be read and transmitted by other devices.

[0032] In step 320, these data are now evaluated and processed, for example, by averaging them over a specific time period, transforming them into a predetermined form, or converting them into matching values ​​using a predetermined calculation method.

[0033] Next, in step 330, these obtained values ​​are compared with one or more limit values. If the values ​​are within a predetermined range, the control device continues to continuously check the measured values ​​and evaluate the next series of measured data, returning to step 310 (or alternatively 320). However, if the values ​​exceed predetermined limit values ​​or thresholds indicating the need to heat the exhaust aftertreatment system, this heating is initiated in step 340. This may involve immediately turning on the internal combustion engine or pre-heating the exhaust aftertreatment system electrically, or it may involve determining a specific time at which the heating begins. These subsequent steps then correspond to... Figure 2 Steps 220 or 230 in the process.

[0034] Alternatively, in step 330, instead of directly comparing the evaluated current measurement data with the threshold, step 370 might predict future values ​​based on existing values ​​using different calculation methods.

[0035] When a suitable prediction is made, the value obtained for a specific future point in time or time period is compared with a threshold in step 380. If the calculated future value is within a predetermined limit, heating is not planned, and other values ​​are evaluated or predicted, returning to step 370. However, if at least one of the predicted values, which is important to the determination process, is outside a predetermined limit (above and / or below, depending on the value), heating of the exhaust aftertreatment system is started in step 340. This may involve immediate heating, determining the time when heating should begin or when the internal combustion engine should be turned on, or determining a change in the rules for turning on and heating. Of course, current measurement data from steps 310 or 320 can also be incorporated into the prediction in step 370.

[0036] Instead of the evaluation or prediction based on the current measurement data in steps 320 and 370, or in addition to the evaluation or prediction based on the current measurement data in steps 320 and 370, the control device may also use data obtained from other sources or stored in or connected to the control device at the time of determination. The control device obtains this data in step 360 by calling from a storage device or via a communication connection. This data can then be used, either alone or together with the current data, either directly or with prior further processing, in the threshold comparison.

[0037] Measurements from sensors 31, 32, 33, 34, and other elements, acquired during the hybrid's operation to date, can be obtained (310) and evaluated (320). This can be done, for example, by using values ​​measured currently and continuously and / or evaluating data measured and stored over longer periods, or by data available via communication links. These measurements may include, for example, temperatures at one or more points in the exhaust system, particularly the temperature of the exhaust aftertreatment system, measured at appropriate points by sensor 31, but alternatively or additionally, the temperature of the exhaust stream measured by 33 before the exhaust aftertreatment system or by 34 after the exhaust aftertreatment system. Furthermore, measurements include exhaust characteristic values ​​relating to the exhaust stream and, particularly, the composition and / or concentration and / or volume and / or components of the hazardous substances contained therein, or data that allows for their deduction. These measurements can also be measured by sensor 32 before and / or after the exhaust aftertreatment system, or calculated from data. Similarly, motor power data, such as energy consumption and fuel consumption, can be evaluated, for example, the average power over a predetermined time period or the maximum power invoked. All of these and other data can be evaluated individually or in combination to control the heating of the exhaust aftertreatment system. The data can also be stored or retrieved in a suitable manner (360) to supplement current measurements. Of course, the evaluation of measurements can also be used in combination with determined time intervals as described above.

[0038] Here, one or more thresholds can be used in step 330 to determine whether heating is needed or what heating measures to take. If the temperature is below (e.g., the required or optimal operating temperature) and / or above (e.g., harmful substances in the exhaust stream) a threshold, it can be determined in step 340 when and whether to engage the internal combustion engine. The system can optionally identify which threshold is valid for the current and predetermined or currently predicted upcoming road segment; when the vehicle is, for example, in a specific area with specific management (e.g., regulations) and this is known through the vehicle's positioning system, the currently used threshold can be adjusted accordingly, such as the localizable limits of a particular region, such as urban living spaces like city centers, rural areas and farms (within which, for example, combine harvesters operate in a different mode than on rural roads outside villages, on their paths to fields), coastal areas, and ports (different from open water and high seas areas). In this way, temporally restricted or localized, such as urban operating limitations of the internal combustion engine can be taken into account, for example.

[0039] Measurement data and / or predicted data can also be used in step 340 to modify the established rules for engaging the internal combustion engine. For example, when an evaluation of the measurement data indicates that specific limits or thresholds are consistently reached under certain conditions, the power delivery of the internal combustion engine can be adjusted accordingly, or the previously determined time interval can be shortened until the next engagement for heating. This adjustment can also be persistently determined. In this way, the rules for engagement can be variably adjusted in hybrid operation, particularly in a feedback control manner, where the rules are continuously checked to determine whether the currently used rules correspond to optimal operation of all components, and if not, the rules are adjusted. Different rules can also be determined for different operating modes: pure electric operation, pure internal combustion engine operation, and combined operation of the electric motor and internal combustion engine.

[0040] In addition to directly evaluating the measurement data and making decisions based on it, according to one possible embodiment of the invention, a prediction can also be determined in step 370. This prediction may include numerical extrapolation based on the measurement data over a determined future time period, or more expensive methods for prediction and feedback, such as fuzzy logic methods and neural networks. When, for example, it is known from previous operation or stored data (360) how exhaust emissions rise or fall depending on engine engagement, this data can be used to estimate the expected future characteristics of temperature and emissions through appropriate calculations and, based on this, determine (370) the regulation for engine engagement. For this purpose, the predicted data is again compared with limit values ​​in step 380, similar to step 330 for the current measurement values.

[0041] The determination of whether heating is needed and the corresponding predictions within a predetermined time period can also be based on navigation data, traffic forecasts, weather forecasts, and similar predictions. When, for example, the vehicle's navigation system can determine which road segment the vehicle is on, data about the expected upcoming road segment can be inferred, at least within a limited time period, such as up to the next junction. This data may include information about the speed characteristics of vehicles there, delay information such as traffic jams, traffic lights, field and ocean markers, and / or road segment characteristics such as uphill, downhill, and speed limits, as well as additional information from communication connections, such as local weather conditions from the Internet. Vehicle adjustments selected by the driver (e.g., autonomous driving and cost-optimized driving) and typical driver characteristics and user-related preferences, such as the vehicle's air conditioning, acceleration characteristics, and braking characteristics, can also be used for these predictions. Based on this, the system can also assess the power consumption value at the next time and determine, according to established rules, whether and when the operating temperature of the exhaust aftertreatment system is likely to be below a threshold and whether and when heating is needed. These data can also be combined with current or older measurements, such as those from hybrid operation, to make predictions as accurate as possible. Specific characteristic data can also be pre-stored in the system or accessed via communication connections, for example, on the manufacturer's side, to illustrate the interrelationships between temperature, power, and emissions values, taking into account the aforementioned additional information, and to use this data for calculations and predictions.

[0042] As an alternative to local regulation, or in addition to local regulation, measurement data can also be transmitted at other locations via communication links, for example, to a central processing unit, where the measurement data is evaluated and / or the corresponding forecast data is calculated, and only the resulting rules for starting the motor are transmitted back to the local control unit.

[0043] Another possibility for achieving the desired operating temperature is to preferably directly heat portions of the exhaust aftertreatment system (or the entire system) via an electric heating device 24. Thus, sensors, gas mixing elements, catalytic converters, piping, and other components can be electrically heated, for example, in specific areas or entirely. This has been achieved with low-pressure hybrids, but higher voltages are advantageous.

[0044] When the internal combustion engine is not in operation or not yet connected, especially for parts that already have electrically heated exhaust aftertreatment systems, see [link to relevant documentation]. Figure 2Step 220. Then, electric heating can be performed continuously, at defined intervals, or immutably within defined time periods, with modulated power before machine startup or before the internal combustion engine is engaged. Here, electric heating can also occur independently of whether the internal combustion engine is engaged to increase drive power or, according to the invention, to increase the temperature of the exhaust aftertreatment system. For example, the aforementioned predictive model can be used so that the system has been preheated by electric heating beforehand at the expected high drive power and thus the expected engagement of the internal combustion engine for drive.

[0045] Once the control unit determines that the internal combustion engine should be immediately turned on, a signal for electric heating can be sent to the corresponding element. Alternatively, it can be determined, for example, that electric heating is performed at specific time intervals when the internal combustion engine is turned off, even if the internal combustion engine is not turned on or not safely turned on within a foreseeable time. Similarly, optional temperature measurement can again be incorporated into the decision for electric heating, thus electrically heating the exhaust aftertreatment system below a threshold temperature until a desired minimum temperature is reached. Upon reaching this minimum temperature, the internal combustion engine can be turned on, either additionally or alternatively. In one possible embodiment of the invention, the signal for turning on the internal combustion engine is given only when a predetermined temperature of the exhaust aftertreatment system is reached.

[0046] It is also possible that, when the motor controller determines or anticipates a high-power start-up of the internal combustion engine, a preliminary heating phase is always performed first. During this initial phase, the internal combustion engine operates at low power, and the remaining drive power continues to be provided by the electric motor. After a predetermined time or once the desired operating temperature of the exhaust aftertreatment system is reached, the power of the internal combustion engine can be increased. The power of the internal combustion engine can also be increased gradually or continuously from the heating phase.

[0047] The control unit responsible for starting the internal combustion engine to heat it, determining regulation data, predicting data, and monitoring temperature values, can be the motor controller. However, it can also involve separate regulation units or other control mechanisms that perform other tasks or are only designed for this regulation.

[0048] When the internal combustion engine should be engaged to heat the exhaust aftertreatment system, the control unit ideally allows only this much power so that emissions are always kept below predetermined limits. Emissions generated by engaging the internal combustion engine should therefore be continuously taken into account during controlled heating to ensure they do not exceed the limits. The internal combustion engine operates at a lower power for heating; the remaining power used by the vehicle is preferably provided by the electric motor.

[0049] Therefore, in one possible implementation, after the internal combustion engine is turned on, the volume and / or composition of the exhaust flow are calculated, either temporarily and partially, by one or more sensors, or by data stored or retrieved via a communication connection. This calculation can be performed continuously or at defined intervals. A control device, such as a motor controller, processes the sensor signals and monitors whether the threshold values ​​are met. Similarly, regionally prescribed, i.e., legally mandated limits, can be used as thresholds, as well as other or additional thresholds deviating from them (e.g., those determined by the manufacturer). For example, it is conceivable to use different thresholds graded below the legally mandated limits to determine when to initiate different measures to improve emissions values.

[0050] The threshold is preferably stored in the storage unit of the control device for processing.

[0051] If the measured and received sensor signals on the control unit indicate that a threshold in the exhaust flow is exceeded, the control unit can now initiate additional measures that may result in the exhaust aftertreatment system reaching its minimum operating temperature or a specific desired operating temperature.

[0052] Different methods for further heating the exhaust aftertreatment system are also possible here. For example, a limited exhaust flow, particularly suitable for heating, can be directed to the exhaust aftertreatment system continuously or for a limited time, such as less than 600 seconds, advantageously less than 60 seconds, and especially advantageously only a few seconds, which heats the exhaust aftertreatment system for subsequent higher exhaust flows.

[0053] For this purpose, various substances can be added to the exhaust stream, substances suitable for increasing the temperature of the exhaust aftertreatment system. One possibility is to supply combustible materials to the exhaust stream inside the motor or directly to the exhaust aftertreatment system, so that these combustible materials can at least partially be converted into heat through the combustion process. Such substances are, for example, fuels, nitric oxide (NO), methanol, and other additives known in the industry, which can be injected at suitable locations. Alternatively or additionally, adsorbable / absorbable substances are enriched in the combustion gases and / or supplied to the exhaust stream, which then at least partially contribute to the heating of the exhaust aftertreatment system. Substances suitable for this purpose are also known, such as water, hydrogen urinate (HWL), ammonia (NH3), and nitrogen oxides (NO, NO2). At a subsequent point in time, the adsorption / absorption sites of the exhaust aftertreatment system should be regenerated.

[0054] It is also advantageous to use methods in which different measures for heating the exhaust aftertreatment system are combined with each other, such as non-mandatory full and non-mandatory sequential electronic heating of at least one (if necessary later) gas-passing, preferably functional unit (e.g., mixing pipe, gas mixer, catalytic converter, etc.) to bring the unit to its minimum operating temperature; for example, generating absorbent heat in the exhaust aftertreatment system due to the metering of reducing agents (e.g., NH3, HWL, propylene, etc.) and / or by conveying and adsorbing unburned fuel molecules; measures in the motor for increasing exhaust temperature together with high-pressure AGR (exhaust gas recirculation) and / or low-pressure AGR; conveying oxidizable molecules (hydrocarbons, unburned fuel, NH3, etc.) to oxidizing catalytic converter components to generate combustion heat within the exhaust aftertreatment system.

[0055] The method according to the invention relates to every type of hybrid machine, such as low-voltage hybrids, high-voltage hybrids, plug-in hybrids, range-extender hybrids, and especially hybrid vehicles. The described method is also independent of the type of hybrid machine, including, for example, low-duty (LD), medium-duty (MD), and high-duty (HD) hybrids, including buses; off-highway (OHW) machines, including motorboats, aircraft such as small planes, locomotives, or large motors for example, marine applications. The method can be used with any form of internal combustion engine in a hybrid, such as hybrids with diesel motors, gasoline motors, or motors that run on gas or methanol.

[0056] Because all exhaust aftertreatment systems require a minimum temperature above ambient temperature to convert harmful gases, the methods described can be used for every type and combination of exhaust aftertreatment for hybrid engines, as well as for NOx storage catalysts such as NSC (NOx Storage Converter) and three-way catalytic converters (TWC); for NH3 storage catalysts such as SCR (Selective Catalytic Reduction) catalysts; for oxidation catalysts such as DOC (Diesel Oxidation Catalyst), NSC, TWC, AMOX (NH3 Oxidation Catalyst); and for reduction catalysts such as SCR, NSC, and TWC; and for particulate filters with and without oxidation or reduction coatings. The limiting temperature can be adjusted accordingly to the desired and optimal operating temperature.

[0057] Here, the method may include, particularly when detecting and measuring data, heating elements, and adjusting additives and operating conditions, any components of the exhaust aftertreatment system, such as gas mixers and dual-material mixers; liquid atomizers and evaporators (hydraulic, mechanical, and electrical operation), including their wiring terminals, cables, and software; catalyst housings (tanks), filters, low-pressure zones, gas scrubbers, piping, disconnecting elements, mixing chambers, and other metal components that may be detachable from each other; sensors (volume flow rate, temperature, NOx, particles, Lambda, NH3, O2, NO, NO2, N2O, absolute pressure, differential pressure, oxidation potential, conductivity, etc.) along with their wiring terminals, cables, and software, and any combination thereof.

[0058] It should be emphasized again that the listed methods and steps, such as predefined internal combustion engine activation, prediction of peak power, evaluation of measurement data, prediction of future measurement data, and modification of predefined activation rules, can be combined or used in parallel to achieve optimal emission characteristics comfortably with desired drive power and energy consumption optimization.

Claims

1. A method for exhaust aftertreatment in a hybrid machine comprising at least one electric motor (2) and an internal combustion engine (3), wherein, The method includes: The hybrid machine is operated in a first operating mode (200), in which only the electric motor (2) is turned on and the internal combustion engine (3) is turned off; Determine (210) whether the exhaust aftertreatment system (20) of the hybrid engine needs to be heated; and If heating is required, the internal combustion engine (3) shall be temporarily switched on (230) to heat the exhaust aftertreatment system (20). When the internal combustion engine should be turned on to heat the exhaust aftertreatment system, the control unit ideally allows only so much power so that emissions are always kept below a predetermined limit. The internal combustion engine operates at a lower power for heating, while the remaining power called upon by the vehicle continues to be provided by the electric motor. In electric drive mode, the internal combustion engine is turned on for heating at predetermined time intervals. The duration of the internal combustion engine on and the operating state selected for this purpose can also be predetermined, thus resulting in irregular or regular periodic on / off cycles.

2. The method according to claim 1, wherein, Based on the evaluation (320) of the measurement data, a determination (210) is made as to whether the exhaust aftertreatment system needs to be heated, wherein the measurement data has been acquired at least in part during the operation of the hybrid engine to date, wherein the measurement data includes at least one of the following: the temperature of the exhaust aftertreatment system, the power data of the electric motor and / or the internal combustion engine, and values ​​for exhaust flow components.

3. The method according to claim 2, wherein, Determining whether a heated exhaust aftertreatment system is required includes: (370) a prediction of future measurement data expected within a specific time period, wherein the prediction is calculated based on stored and / or data available through a communication connection and / or current measurement data.

4. The method according to claim 3, wherein, The prediction is calculated based on data that determines the expected drive power required within a predetermined future time period.

5. The method according to claim 3 or 4, wherein, The measured and / or predicted measurement data are compared with at least one predetermined threshold (330, 380), and it is determined whether heating is required when the data is below or above at least one predetermined threshold (340).

6. The method according to any one of claims 1 to 4, wherein, The internal combustion engine is switched on at a predetermined time and / or for a predetermined duration and / or with a predetermined power output.

7. The method according to claim 6, wherein, The predetermined time of connection and / or the predetermined duration and / or the predetermined power output change during operation based on at least one of the data from stored data, transmitted data, or detected measurement data.

8. The method according to any one of claims 1 to 4, further comprising: During a predetermined time period, before and / or during the internal combustion engine is turned on (230) for heating the exhaust aftertreatment system, at least one part of the exhaust aftertreatment system is electrically heated (220).

9. A computing unit configured to perform all the method steps of the method according to any one of the preceding claims.

10. A computer program product having a computer program that, when implemented on a computing unit, causes the computing unit to perform all the method steps of the method according to any one of claims 1 to 8.

11. A machine-readable storage medium having a computer program stored thereon, which, when implemented on a computing unit, causes the computing unit to perform all the method steps of the method according to any one of claims 1 to 8.

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