Abstract: Determining a functionality of an exhaust gas sensor in an exhaust gas system having a catalytic converter and a first exhaust gas sensor upstream of the catalytic converter and a second exhaust gas sensor downstream of the catalytic converter. The first and the second exhaust gas sensors are heated to a temperature above a minimum operating temperature. A first sensor signal of the first exhaust gas sensor; and a second sensor signal of the second exhaust gas sensor are determined. The first and the second sensor signals are compared in an operating period in which a temperature of the at least one catalytic converter does not exceed a temperature threshold value; and an operating parameter of the first exhaust gas sensor (121) is determined on the basis the comparison.

Abstract: Device and method for correcting an offset in a signal of a first sensor for determining a residual oxygen content in an exhaust gas. A first actual ratio of air and fuel being determined as a function of a first residual oxygen content, a second actual ratio of air and fuel being determined as a function of a second residual oxygen content, a first offset of a first actual ratio relative to a reference ratio being determined for the first actual ratio when the second actual ratio is greater than the reference ratio, a second offset of a first actual ratio relative to the reference ratio being determined for the first actual ratio when the second actual ratio is smaller than the reference ratio, and a deviation being detected between the first offset and the second offset.

Abstract: A method is directed to operating an internal combustion engine having at least one catalytic converter, wherein control interventions of a lambda control for controlling an exhaust gas composition of the engine are deactivated. The method includes the steps of ascertaining a current exhaust gas composition upstream of the catalytic converter, determining a current oxygen fill level of the catalytic converter on the basis of the ascertained current exhaust gas composition, ascertaining a planned control intervention on a composition of an air-fuel mixture supplied to the engine on the basis of the determined current oxygen fill level of the catalytic converter, ascertaining a current exhaust gas composition downstream of the catalytic converter, ascertaining a future exhaust gas composition downstream of the catalytic converter resulting on the basis of an air-fuel mixture already supplied to the engine, and reactivating the lambda control and specifying a control intervention to be carried out.

Abstract: A method for operating an internal-combustion engine having an exhaust gas catalyst, a first exhaust gas sensor upstream of the exhaust gas catalyst and a second exhaust gas sensor downstream of the exhaust gas catalyst. A fill level of an exhaust gas component that can be stored in the exhaust gas catalyst is determined using a theoretical catalyst model, into which, as the input value, a signal of the first exhaust gas sensor (a first signal); a signal of the second exhaust gas sensor (a second signal); and a target signal are provided. The target signal corresponds to the signal that would be expected at the determined fill level in the exhaust gas catalyst. The catalyst model is reinitiated when the deviation of the second signal from the target signal exceeds a predetermined threshold value. The fill level is also regulated, and an air-fuel mixture is adjusted.

Abstract: A method for ascertaining fill levels of first and second exhaust gas catalytic converters in an exhaust gas system downstream from an internal combustion engine with respect to at least one exhaust gas component. The method includes detecting, using a sensor upstream from the first exhaust gas catalytic converter, at least one operating parameter of the exhaust gas system, ascertaining the fill level of the first exhaust gas catalytic converter based on the detected at least one operating parameter using a first calculation rule, ascertaining a total fill level of the first exhaust gas catalytic converter and second exhaust gas catalytic converter based on the ascertained at least one operating parameter using a second calculation rule, and ascertaining the fill level of the second exhaust gas catalytic converter as a difference between the total fill level and the fill level of the first exhaust gas catalytic converter.

Abstract: The invention relates to a method (200) for operating an internal combustion engine (110), comprising providing and combusting an air-fuel mixture of a first composition, determining (210) a current composition of a combustion exhaust gas produced during the combustion, determining (220) an emission collective, which comprises a total amount emitted over a predefined interval for at least one component of the combustion exhaust gas, from multiple successively determined current compositions of the combustion exhaust gas, and setting (250) a second composition of the air-fuel mixture depending on the emission collective determined. The invention also relates to a computing unit and a computer program product for carrying out such a method.

Abstract: Device and method for correcting an offset in a signal of a first sensor for determining a residual oxygen content in an exhaust gas. A first actual ratio of air and fuel being determined as a function of a first residual oxygen content, a second actual ratio of air and fuel being determined as a function of a second residual oxygen content, a first offset of a first actual ratio relative to a reference ratio being determined for the first actual ratio when the second actual ratio is greater than the reference ratio, a second offset of a first actual ratio relative to the reference ratio being determined for the first actual ratio when the second actual ratio is smaller than the reference ratio, and a deviation being detected between the first offset and the second offset.

Abstract: A method for operating an internal-combustion engine having an exhaust gas catalyst, a first exhaust gas sensor upstream of the exhaust gas catalyst and a second exhaust gas sensor downstream of the exhaust gas catalyst. A fill level of an exhaust gas component that can be stored in the exhaust gas catalyst is determined using a theoretical catalyst model, into which, as the input value, a signal of the first exhaust gas sensor (a first signal); a signal of the second exhaust gas sensor (a second signal); and a target signal are provided. The target signal corresponds to the signal that would be expected at the determined fill level in the exhaust gas catalyst. The catalyst model is reinitiated when the deviation of the second signal from the target signal exceeds a predetermined threshold value. The fill level is also regulated, and an air-fuel mixture is adjusted.

Abstract: Determining a functionality of an exhaust gas sensor in an exhaust gas system having a catalytic converter and a first exhaust gas sensor upstream of the catalytic converter and a second exhaust gas sensor downstream of the catalytic converter. The first and the second exhaust gas sensors are heated to a temperature above a minimum operating temperature.; A first sensor signal of the first exhaust gas sensor; and a second sensor signal of the second exhaust gas sensor are determined.

Abstract: A method for ascertaining a fill level of at least one exhaust-gas component, which can be stored in a catalytic converter and which is generated in a combustion process, in the catalytic converter, wherein a variation of the fill level of the at least one exhaust-gas component in the catalytic converter during the combustion process is determined, wherein, during time periods in which the combustion process is not operated, a diffusion-induced change of the fill level of the at least one exhaust-gas component in the catalytic converter is determined, and wherein, on the basis of the determined variation during the combustion process and the diffusion-induced change, a fill level of the at least one exhaust-gas component in the catalytic converter is ascertained. The invention furthermore relates to a processing unit and to a computer program for carrying out such a method.

Abstract: The invention relates to a method (200) for operating an internal combustion engine (110) having at least one catalytic converter (122), wherein control interventions of a lambda control for controlling an exhaust gas composition of the internal combustion engine are deactivated, comprising ascertaining a current exhaust gas composition upstream of the at least one catalytic converter (122), determining a current oxygen fill level of the at least one catalytic converter (122) on the basis of the ascertained current exhaust gas composition, ascertaining (210) a planned control intervention on a composition of an air-fuel mixture supplied to the internal combustion engine (110) on the basis of the determined current oxygen fill level of the at least one catalytic converter, ascertaining a current exhaust gas composition (123) downstream of the at least one catalytic converter (122), ascertaining a future exhaust gas composition (123) downstream of the at least one catalytic converter (122) resulting on the basi

Abstract: A method (200) for ascertaining a catalytic converter state is proposed, wherein an exhaust-gas catalytic converter (130) is monitored on the basis of a catalytic converter model. Here, the catalytic converter model is adapted (250) in a manner dependent on measured values detected by means of one or more sensors (145, 147), wherein a frequency and/or a degree of the adaptation of the catalytic converter model is detected (260). The catalytic converter state is ascertained (270) as non-critical if the frequency and/or the degree of the adaptation do not exceed a predeterminable threshold value or is ascertained (270) as critical if the frequency and/or the degree of the adaptation exceed the predeterminable threshold value.

Abstract: A method for controlling an internal combustion engine with a catalytic converter for exhaust-gas aftertreatment, comprising specification of a target fill level profile is proposed, which fluctuates between an upper threshold value and a lower threshold value, of at least one exhaust-gas component that can be stored in the catalytic converter, determination of a present fill level of the at least one exhaust-gas component in the catalytic converter on the basis of a theoretical catalytic converter model, and control of the internal combustion engine so as to generate an exhaust gas with a target concentration of the at least one exhaust-gas component such that a deviation between the present fill level and the present target fill level in accordance with the target fill level profile is reduced. A processing unit and a computer program product for carrying out a method of said type, and a vehicle which is configured for carrying out the method, are likewise proposed.

Abstract: A method for diagnosing a plurality of lambda sensors which are arranged upstream of an exhaust gas catalytic converter in a plurality of exhaust gas banks of a multi-flow exhaust gas system of an internal combustion engine. An opposite lambda offset of the lambda sensors is identified (54) when a difference (?T) between a measured exhaust gas temperature (Tmeasure) and a modeled exhaust gas temperature (Tmod) downstream of the exhaust gas catalytic converter overshoots a threshold value (S).

Abstract: Operating a combustion engine with an exhaust gas aftertreatment system. In one example, a method includes determining a level of at least one exhaust gas component using a theoretical catalytic converter model in which at least one signal of a first exhaust gas sensor is input as a first signal, detecting a signal of a second exhaust gas sensor downstream of the exhaust gas catalytic converter as a second signal, determining a deviation of the second signal from a target signal, reinitializing the catalytic converter model if the deviation of the second signal from the target signal exceeds a predetermined threshold value, regulating the level by setting an air-fuel mixture supplied to the combustion engine according to a target level based on the determined level, determining a deviation between the first and the second signals, and correcting the first signal.

Abstract: A method for adapting modeled reaction kinetics of a reaction taking place in a catalytic converter, with model-based fill level feedback control. The method includes specifying a setpoint value for at least one fill level of at least one exhaust-gas component that can be stored in the catalytic converter; calculating at least one fill level of the catalytic converter using a signal of an exhaust-gas sensor upstream of the catalytic converter and using a catalytic converter model with at least one storage capacity and reaction kinetics of the at least one reaction taking place in the catalytic converter; setting an air-fuel mixture such that the calculated fill level approximates the specified setpoint value; ascertaining a difference between a signal of the exhaust-gas sensor upstream of the catalytic converter and a signal of an exhaust-gas sensor downstream of the catalytic converter; and deactivating the fill-level-dependent setting of the air-fuel mixture.

Abstract: A method is proposed for regulating a fill level of an exhaust component storage of a catalyst (26) of an internal combustion engine (10), wherein the regulating of the fill level is done by using a system model (100), comprising a catalyst model (102), and wherein uncertainties of measured or model variables influencing the regulating of the fill level are corrected by an adaptation, which is based on signals of an exhaust gas probe (34) arranged at the outlet side of the catalyst (26). The method is characterized in that the adaptation takes multiple pathways (200, 210, 220), wherein signals from different signal regions (260, 280, 300) of the exhaust gas probe (34) situated at the outlet side are processed on different pathways. An independent claim is addressed to a controller designed to carry out the method.

Abstract: A method for operating an exhaust-gas burner (B) of a vehicle (100) which has at least an internal combustion engine (V) and a catalytic converter (C1, C2), wherein exhaust gases (22, 24) of the exhaust-gas burner (B) are merged, upstream of the catalytic converter (C1, C2), with exhaust gases (12) of the internal combustion engine (V), forming an exhaust-gas mixture, wherein a lambda value of the exhaust gases (22, 24) of the exhaust-gas burner (B) is set in a manner dependent on a lambda value of the exhaust gases (12) of the internal combustion engine (V).

Abstract: A method for operating an engine system that includes an internal combustion engine and an exhaust aftertreatment device. The method includes: carrying out a filling control in order to regulate a filling level of the exhaust aftertreatment device as a function of a predefined filling level setpoint value, a lambda setpoint value for a lambda regulation being predefined as a manipulated variable, adapting the filling control with the aid of an adaptation variable that indicates a correction value for the lambda setpoint value, and storing an adaptation value as a function of an operating range of the engine system, the adaptation value in question being updated with the value of the adaptation variable for the instantaneous operating range.

Abstract: Operating a combustion engine with an exhaust gas aftertreatment system. In one example, a method includes determining a level of at least one exhaust gas component using a theoretical catalytic converter model in which at least one signal of a first exhaust gas sensor is input as a first signal, detecting a signal of a second exhaust gas sensor downstream of the exhaust gas catalytic converter as a second signal, determining a deviation of the second signal from a target signal, reinitializing the catalytic converter model if the deviation of the second signal from the target signal exceeds a predetermined threshold value, regulating the level by setting an air-fuel mixture supplied to the combustion engine according to a target level based on the determined level, determining a deviation between the first and the second signals, and correcting the first signal.