A method for controlling a fill level of an exhaust gas component store of a catalytic converter of an internal combustion engine, in which the fill level is controlled by using a system model, which includes a catalytic converter model, and uncertainties of measurement or model variables, which influence the control of the fill level, being corrected by an adaptation that is based on signals of an exhaust-gas probe situated on the output side of the catalytic converter. The method provides that an adaptation requirement is learned as a function of the operating point, the learned adaptation requirement is stored as a function of the operating point, and a distinction is made based on the operating point dependency between different causes of the uncertainties. Also described is a control unit to carry out the method.

A learning use data set showing relationships among an engine speed, an engine load rate, an air-fuel ratio of the engine, an ignition timing of the engine, an HC or CO concentration of exhaust gas flowing into an exhaust purification catalyst and a temperature of the exhaust purification catalyst is acquired. The acquired engine speed, engine load rate, air-fuel ratio of the engine, ignition timing of the engine, and HC or CO concentration of the exhaust gas flowing into the exhaust purification catalyst are used as input parameters of a neural network and the acquired temperature of the exhaust purification catalyst is used as training data to learn a weight of the neural network. The learned neural network is used to estimate the temperature of the exhaust purification catalyst.

A method and control device for monitoring the function of a particulate filter in an exhaust gas duct of an internal combustion engine. A soot emission in the exhaust gas duct downstream from the particulate filter is determined with a particle sensor, an expected soot emission after a limit particulate filter at the location of the particle sensor is simulated and a comparison value is ascertained. A good particulate filter is found if the measured soot emission is less than the comparison value of the simulated soot emission. A defective particulate filter is found if the measured soot emission is higher than the comparison value of the simulated soot emission. The simulated soot emission is determined as being a simulated soot particle concentration at the installation site of the particle sensor such that a basic soot concentration in a soot concentration model is corrected at least with an oxygen correction.

A learning use data set showing relationships among an engine speed, an engine load rate, an air-fuel ratio of the engine, an ignition timing of the engine, an HC or CO concentration of exhaust gas flowing into an exhaust purification catalyst and a temperature of the exhaust purification catalyst is acquired. The acquired engine speed, engine load rate, air-fuel ratio of the engine, ignition timing of the engine, and HC or CO concentration of the exhaust gas flowing into the exhaust purification catalyst are used as input parameters of a neural network and the acquired temperature of the exhaust purification catalyst is used as training data to learn a weight of the neural network. The learned neural network is used to estimate the temperature of the exhaust purification catalyst.

A method of adaptively sampling data to determine the start of injection in a solenoid actuated valve of a fluid injector includes, in an operating cycle or portion thereof of the valve, sampling the signal of current through a solenoid of the valve at sampling points having a pre-defined interval therebetween. At each sampling point, determining the value of the first derivative of current and detecting the sampling point at which the first derivative achieves a maximum as the start of injection. Values of the first derivative of the sampling points immediately preceding and immediately following the start of injection are determined. In a subsequent operating cycle, sycrhonisation of sampling is altered to shift sampling times depending on the values of the first derivative of the sampling points immediately preceding and immediately following the start of injection.

A method for adapting a characteristic curve of a nitrogen oxide sensor of a combustion engine with exhaust gas recirculation having the first nitrogen oxide sensor upstream of an SCR catalytic converter and a second nitrogen oxide sensor downstream of the SCR catalytic converter includes determining that a particle filter is in a regeneration phase, increasing the exhaust gas recirculation rate, interrupting the supply of urea by a urea injection device, acquiring first nitrogen oxide values from signals generated by the first nitrogen oxide sensor, determining that the first nitrogen oxide values are within a first nitrogen oxide interval, acquiring values from second nitrogen oxide signals generated by the second nitrogen oxide sensor, and determining that the second nitrogen oxide values are within a second nitrogen oxide interval, and adapting the characteristic curve of the first nitrogen oxide sensor by the second nitrogen oxide values.

A method for operating a system having an internal combustion engine and an exhaust aftertreatment system having an SCR catalyst, wherein the internal combustion engine is controlled on the basis of at least one process parameter that influences a nitrogen oxide raw emission, wherein aging detection is performed for the SCR catalyst, wherein in a first operating mode of the internal combustion engine, if aging of the SCR catalyst is detected, the at least one process parameter is changed in the direction of a reduced nitrogen oxide raw emission, wherein the internal combustion engine is controlled on the basis of the changed at least one process parameter.

A method for correcting for aging in particulate matter sensors for a diesel engine includes calculating calculated particulate matter values for a modeled diesel engine exhaust system over a period of time, measuring measured test particulate matter values with a test particulate matter sensor over the period of time in a test diesel engine exhaust system, determining differences between the calculated particulate matter values and the measured test particulate matter values from the test particulate matter sensor over the period of time, and correcting measured particulate matter values in at least one other particulate matter sensor over a same period of time based on the determined differences to obtain a corrected particulate matter value. A particulate matter sensor arrangement and a vehicle including a particulate matter sensor arrangement are also provided.

A method and system controls a regeneration of a particle filter of an internal combustion engine. A first value is measured for the oxygen content in exhaust gas upstream from the particle filter. A second value is measured for the oxygen content in exhaust gas downstream from the particle filter. The particle filter is determined to be free of soot when the second value for the oxygen content is equal to the first value for the oxygen content.

Systems and associated methods of treating diesel exhaust in a vehicle are disclosed. An example method includes providing an exhaust aftertreatment device in an exhaust tailpipe, and a first nitrogen oxide (NO.sub.x) sensor upstream of the exhaust aftertreatment device, with the exhaust aftertreatment device configured to reduce NO.sub.x present in an exhaust flow through the exhaust aftertreatment device with a treatment fluid applied to the exhaust flow. This example method may also include measuring a concentration of NO.sub.x in the exhaust flow with the first sensor, determining an error in the measurement of the NO.sub.x concentration, and applying a learning corrective adjustment in a subsequent measurement of the NO.sub.x concentration in the exhaust flow in response to that determination. A first magnitude of the learning corrective adjustment may be based at least in part upon a second magnitude of the error in the measurement.