A system and method include determining, by a controller associated with an aftertreatment system, satisfaction of an enabling condition and in response to the satisfaction of the enabling condition pausing, by the controller, hydrocarbon dosing in a regeneration cycle of the aftertreatment system. The system and method also include upon pausing of the hydrocarbon dosing, monitoring, by the controller, an oxidation catalyst of the aftertreatment system for a light-off shift condition.

An exhaust system of an internal combustion engine of a motor vehicle includes a particulate filter where particles are filterable out from the exhaust gas by the particulate filter. A selective catalytic reduction (SCR) catalytic converter through which the exhaust gas from the internal combustion engine is flowable for denitrifying the exhaust gas from the internal combustion engine is disposed downstream of the particulate filter. The exhaust gas of the internal combustion engine is heatable by a combustor at a point disposed upstream of the SCR catalytic converter and downstream of the particulate filter where the combustor provides an exhaust gas of the combustor. Particles are filterable out from the exhaust gas of the combustor by a filter element.

A method of detecting a need for regeneration of an exhaust particulate filter is described. A first pressure drop is detected in a flow section of an exhaust system which includes the exhaust particulate filter. In addition, an exhaust gas temperature is determined. An exhaust gas mass flow flowing through the exhaust particulate filter is then calculated on the basis of the exhaust gas temperature and the pressure drop. Furthermore, a second pressure drop at the exhaust particulate filter is determined. A need for regeneration is detected when the second pressure drop exceeds a predefined pressure limit value that is dependent on the exhaust gas mass flow. Moreover, an exhaust system for an internal combustion engine is presented which includes an exhaust particulate filter.

The invention relates to a method for determining a loading of a soot filter with soot particles from an exhaust gas mass flow of an internal combustion engine in a motor vehicle, a control device for an internal combustion engine having a soot filter, and a computer program product for carrying out the method. In the first step 100 of the method a characteristic curve for the relationship between the exhaust gas mass flow, exhaust gas temperature, ambient pressure, and pressure drop across the soot filter without loading is determined; in the second step 200 a second exhaust gas mass flow and a second pressure drop that occurs during loading of the soot filter are determined; in the third step 300, from the characteristic curve the first pressure drop is determined for which the first and second exhaust gas mass flows have the same value; in the fourth step 400 an estimated value for the loading of the soot filter is computed via a real-time parameter estimation, preferably by use of the gradient method, based on the previously determined parameters. The method allows a reliable determination of the instantaneous loading of a particulate filter, regardless of the type of measuring signals used in each case for characterizing the loading behavior of the soot filter.

The invention relates in particular to a method for adjusting the loading (19) of a particulate filter (9) and to an assembly designed to carry out the method, wherein the exhaust gas aftertreatment unit (8) comprises at least two SCR systems (11, 12) and a particulate filter (9), a first operating material amount being introduced in a metered manner before the first SCR system (11), and a second operating material amount being introduced in a metered manner before the second SCR system (12), the operating material being convertible into a reducing agent. The state of loading of the particulate filter (9) is determined using a model, and, if the determined state of loading is below a previously defined loading range (16), the first operating material amount is adjusted in such a way that the amount of reducing agent is greater than or equal to the amount of reducing agent necessary for nitrogen oxide reduction in accordance with the reaction stoichiometry in the first SCR system (11), and/or, if the determined state of loading is above a previously defined loading range (16), the first operating material amount is adjusted in such a way that the amount of reducing agent is less than the amount of reducing agent necessary for nitrogen oxide reduction in accordance with the reaction stoichiometry in the first SCR system (11).

Provided are an exhaust purification device and an exhaust purification method which can achieve improved fuel efficiency. The exhaust purification device (100) is equipped with: a DOC (5) for occluding hydrocarbons in an exhaust gas; a DPF (6) that is provided downstream from the DOC (5) and is for trapping particulate matter in the exhaust gas; and an ECU (10) for determining, in accordance with the amount of occluded hydrocarbons in the DOC (5), a start time for a regeneration process for removing particulate matter accumulated in the DPF (6).

A method includes operating an engine system including a plurality of cylinders, a plurality of fuel injectors configured to provide fuel the plurality of cylinders, a compression braking system configured to selectably brake at least a first set of the plurality of cylinders, and an exhaust aftertreatment system including at least one catalyst. The method includes determining a condition for brake-fuel operation and, in response to the act of determining, operating the engine in a brake-fuel mode wherein the compression brake is actuated to provide compression braking of the first set of the plurality of cylinders and a second set of the plurality of cylinders receives and combust fuel provided from respective ones of the plurality of fuel injectors.

A control system is provided for a diesel particulate filter (DPF) system of a diesel engine configured for operation in an off-highway vehicle. The control system includes a controller configured to receive a signal corresponding to a fill state of the DPF being at or above a first threshold. The controller is configured to selectively induce a parasitic load on the diesel engine to increase an operating temperature of the engine in response to receiving the signal.

A controller for a hybrid electric vehicle including an internal combustion engine is provided. The internal combustion engine includes a filter arranged in an exhaust passage collect particulate matter from exhaust gas. The controller executes a first deceleration control process, a second deceleration control process, and a selection process. The first deceleration control process uses a fuel cutoff process when deceleration of the hybrid electric vehicle is required. The second deceleration control process does not use the fuel cutoff process when deceleration of the hybrid electric vehicle is required. The selection process selects execution of the second deceleration control process when a PM deposition amount is greater than or equal to a threshold value and selects execution of the first deceleration control process when the PM deposition amount is less than the threshold value.

A controller for a hybrid electric vehicle including an internal combustion engine is provided. The internal combustion engine includes a filter arranged in an exhaust passage collect particulate matter from exhaust gas. The controller executes a first deceleration control process, a second deceleration control process, and a selection process. The first deceleration control process uses a fuel cutoff process when deceleration of the hybrid electric vehicle is required. The second deceleration control process does not use the fuel cutoff process when deceleration of the hybrid electric vehicle is required. The selection process selects execution of the second deceleration control process when a PM deposition amount is greater than or equal to a threshold value and selects execution of the first deceleration control process when the PM deposition amount is less than the threshold value.