METHOD FOR OPERATING A MOTOR VEHICLE WITH A COMBUSTION ENGINE

Abstract

The invention concerns a method (200) for operating a motor vehicle (100) with a combustion engine (110), including the determination (210) of a current operating state of the vehicle (100), the determination (220) of an emission state of the vehicle (100) during the determined operating state, carrying out (230) at least one measure to reduce emissions depending on the emission state and evaluating (240) the at least one measure in connection with the operating state with regard to its success in reducing emissions. Furthermore, a computing unit (130) and a computer program product for carrying out such a method (200) are proposed.

Claims

1. A method (200) for operating a motor vehicle (100) with a combustion engine (110), including determining (210), via a computing unit (130), a current operating state of the vehicle (100), determining (220), via the computing unit (130), an emission state of the vehicle (100) during the determined operating state, implementing (230), via the computing unit (130), at least one measure to reduce emissions depending on the emission state, and evaluating (240), via the computing unit (130), the at least one measure in connection with the operating state with regard to its success in reducing emissions.

2. The method (200) according to claim 1, wherein the evaluation (240) of the at least one measure includes a combination of multiple evaluations (240) carried out in connection with comparable operating conditions and/or in relation to identical measures.

3. The method (200) according to claim 2, wherein the combination of multiple evaluations (240) includes a combination of evaluations (240) concerning multiple driving cycles.

4. The method (200) according to claim 2, wherein the combination of multiple evaluations (240) is carried out by determining an emission state and assigning a frequency of the at least one operating state to the integrated emission state and/or by accumulating separately made evaluations (240).

5. The method (200) according to claim 1, wherein the evaluation (240) of the at least one measure includes a weighting of the results of the evaluation (240) depending on a time that has elapsed since the evaluation (240), wherein more recent results are weighted more strongly than older results.

6. The method (200) according to claim 1, wherein the implementation (230) of the at least one measure to reduce emissions depending on the emission state includes an implementation (230) of the at least one measure depending on the result of the evaluation(s) (240) and on the current emission state and the operating state.

7. Method (200) according to claim 1, wherein the at least one measure is selected from the group consisting of a reduction or increase of rich gas components in a catalytic converter purging, a time extension or shortening of a catalytic converter purging, an increase or decrease of a minimum temperature of a catalytic converter (122, 124), an influence of a catalytic converter lambda control towards a rich or lean target lambda, an adjustment of a target oxygen level in a catalytic converter (122, 124), a restriction of permissible operating points of the combustion engine (110), inhibition of engine overrun switch-off, inhibition of start-stop mode, influence on enabling and/or inhibition and/or coordination of intrusive diagnoses, tank ventilation, an operating point shift, dynamic influencing, and exhaust gas recirculation.

8. The method (200) according to claim 1, wherein the operating state is determined on the basis of at least one operating parameter, including one or more of the group consisting of a drive power, a torque, a revolution rate, an exhaust gas mass flow, an exhaust gas composition, a catalytic converter state, a temperature of the combustion engine (110) and/or of a catalytic converter (122, 124), an outside temperature, a driving speed, a geographical position and a personal identity.

9. The method (200) according to claim 1, wherein the emission state includes a current exhaust gas composition and/or a current amount of exhaust gas components selected from the group consisting of carbon monoxide, carbon dioxide, hydrocarbons, nitrogen oxides, ammonia and particles, wherein the emission state is related to an exhaust gas leaving the motor vehicle.

10. (canceled)

11. (canceled)

12. A non-transitory, computer-readable medium containing instructions that when executed by a computer cause the computer to control a motor vehicle (100) with a combustion engine (110), by determining (210) a current operating state of the vehicle (100), determining (220) an emission state of the vehicle (100) during the determined operating state, implementing (230) at least one measure to reduce emissions depending on the emission state, and evaluating (240) the at least one measure in connection with the operating state with regard to its success in reducing emissions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Further advantages and embodiments of the invention result from the description and the enclosed drawing.

[0021] The invention is schematically illustrated in the drawing by means of an exemplary embodiment and is described below with reference to the drawing.

[0022] FIG. 1 shows an example of a motor vehicle that can be used in the context of the invention in a schematic representation

[0023] FIG. 2 shows an advantageous embodiment of a method according to the invention in the form of a highly simplified flowchart.

DETAILED DESCRIPTION

[0024] In FIG. 1, an example of a motor vehicle, such as can be used in the context of the invention, is shown schematically and designated as a whole by 100. The vehicle 100 comprises a combustion engine 110, here for example with six indicated cylinders, an exhaust system 120, which has multiple cleaning components 122, 124, for example catalytic converters and/or particulate filters, as well as a computing unit 130, which is set up for the control of the combustion engine 110 and the exhaust system 120 and is connected to these for data transfer. Furthermore, the computing unit 130 in the example shown is connected for data transfer to sensors 112, 127 which record the operating parameters of the combustion engine 110 and/or the exhaust system 120. It is understood that there may be other sensors that are not displayed.

[0025] In FIG. 2, an advantageous embodiment of a method according to the invention is schematically presented in the form of a highly simplified flowchart and designated as a whole by 200. The method is also described with reference to FIG. 1.

[0026] In a first step 210 of the method 200, one or more operating parameters of the vehicle 100 or the combustion engine 110 are recorded. For this purpose, for example, the sensor 112, for example a thermal sensor and/or a tachometer, can record data and transmit this to the computing unit 130. The detection can also be carried out using models of components of the vehicle, for example a catalytic converter model, which outputs, for example, an oxygen level of the catalytic converter or an ammonia slip through the catalytic converter among other things. From these operating parameters, a current operating state of the vehicle 100 is determined. For example, an engine overrun state can be determined if at the same time a sufficiently high speed of the combustion engine 110 and a very low or missing load requirement are determined.

[0027] In a step 220, an emission state of the exhaust system 120 can also be determined. For this purpose, for example, the sensor 127, for example, a lambda sensor and/or a concentration sensor (for example NH.sub.3 sensor, NO.sub.x sensor) downstream of a catalytic converter 124 of the exhaust system, can record a current emission value of the exhaust gas leaving the exhaust system 120 and transmit it to the computing unit 130.

[0028] The computing unit 130 can then select and initiate one or more measures for emission reduction in a step 230 on the basis of the determined operating state and the emission state.

[0029] In a subsequent step 240, the success of the measure(s) is evaluated. For this purpose, the emission state can be determined again during or after the implementation of the measure(s) and compared with the emission state before the implementation of the measure(s). The result of this evaluation can, for example, be stored in a non-volatile memory 132 of the computing unit 130. The respective operating parameters or states, emission states and measures carried out are stored together with the evaluation. For example, the evaluation of the measure(s) carried out may be positive if a sufficiently high emission reduction has been achieved, negative if no emission reduction could be identified and insufficient if an emission reduction could be identified but not sufficient to achieve a target.

[0030] In step 230 to be carried out later, evaluations stored in the memory 132 can then be accessed in order to adapt the measure(s) accordingly: for example, in comparable operating state-emission situations, a measure already assessed as positive can preferably be re-selected, while negatively evaluated measures are preferably not re-selected again because no success is to be expected. If a measure has been assessed as inadequate in comparable situations or operating conditions, the corresponding measure is carried out, for example, in later steps 230 with increased intensity or combined with other measures to achieve sufficient emission reduction.

[0031] In each subsequent evaluation of a measure, the measure evaluations already carried out in similar operating conditions are preferably weighted with a weighting factor less than 1 in order to take account of an ageing dynamic of the vehicle 100. For example, a measure may include a temperature increase on the catalytic converter 122. For new catalytic converters 122, a minimum operating temperature is typically lower than for already aged catalytic converters 122. Therefore, as the operating time progresses, a temperature increase of a certain extent becomes less effective. A weaker weighting of earlier evaluations compared to later evaluations takes into account the age-related efficacy reduction of the measure faster than would be the case without this weighting.

[0032] To illustrate, a specific example is explained here: After a short interruption of the journey (rotation of the wheels 140 stopped, combustion engine 110 switched off; corresponds for example to the start-stop phase operating state, determined for example from operating parameters travel speed and/or revolution rate of the combustion engine 110) with inhibition of engine overrun switch-off (measure), the exhaust gas composition is considered in relation to carbon monoxide (CO) and/or ammonia (NH.sub.3) and evaluated in comparison to the exhaust gas composition before the interruption of the journey or in comparison to a trip interruption without am engine overrun inhibit. If the measure (inhibition of engine overrun) is successful, it will continue to be used in similar situations in the future (for example a strong reduction of the driving speed with an imminent stop), while in the case of more negative evaluations this measure is subsequently less likely to be selected and instead preferred other measures (for example a temperature increase on the catalytic converter 122, 124 by means of a heating device 121, 123) are chosen in such situations.

[0033] Of course, other combinations of operating states and associated emission scenarios are advantageously usable in the context of the present invention, so that this example is only illustrative and by no means to be considered restrictive. The evaluation and storage within the vehicle result in a massive advantage for the development and application of emission controls, since in principle only available measures, such as emission threshold values and initial selection criteria would have to be stored and the system would then optimize itself in operation. Thus, new measures, for example after retrofitting hardware components, could also be carried out by means of software updates without great application effort, which minimizes resource consumption (for example replacement of ECUs) and workload.