Loading patent…
AssigneeRobert Bosch GmbH
InventorsAndreas Eckert, Herbert Schoemig, Tobias Pfister
Estimating the term…
The present invention relates to a method for operating an exhaust gas aftertreatment apparatus (13) of an internal combustion engine (11), which comprises an oxidation catalytic converter (29), an SCR catalytic converter (35) and a first temperature sensor (32) disposed in the direction of flow downstream of the oxidation catalytic converter (29) and upstream of the SCR catalytic converter (35), an exhaust gas atmosphere capable of exothermal reaction in said oxidation catalytic converter (29) being generated by the metering of hydrocarbons into the exhaust gas (3) upstream of said oxidation catalytic converter (29) during a heating operation. The method is thereby characterized in that a first numerical measurement value of a nominal value of a hydrocarbon conversion in said oxidation catalytic converter (29) is formed, in that a second numerical measurement value of an actual value of the hydrocarbon conversion in said oxidation catalytic converter (29) is determined as a function of the signals of the first temperature sensor (32), in that the second numerical measurement value is compared with the first numerical measurement value and in that the metering of the hydrocarbons is reduced if said second numerical measurement value is smaller than said first numerical measurement value. An independent claim relates to a control device set up for carrying out the method.
Method for operating an exhaust gas aftertreatment apparatus of an internal combustion engine, which comprises an oxidation catalytic converter, an SCR catalytic converter and a first temperature sensor disposed in the direction of flow downstream of the oxidation catalytic converter and upstream of the SCR catalytic converter, an exhaust gas atmosphere capable of exothermal reaction in said oxidation catalytic converter being generated by the metering of hydrocarbons into the exhaust gas upstream of said oxidation catalytic converter during a heating operation, wherein a first numerical measurement value of a nominal value of a hydrocarbon conversion in said oxidation catalytic converter is formed, in that a second numerical measurement value of an actual value of the hydrocarbon conversion in said oxidation catalytic converter is determined as a function of the signals of the first temperature sensor, in that the second numerical measurement value is compared with the first numerical measurement value and in that the metering of the hydrocarbons is reduced if said second numerical measurement value is smaller than said first numerical measurement value.
Open-loop and/or closed-loop control device, which is set up to operate an exhaust gas aftertreatment apparatus of an internal combustion engine, which comprises an oxidation catalytic converter, an SCR catalytic converter and a first temperature sensor disposed in the direction of flow downstream of the oxidation catalytic converter and upstream of the SCR catalytic converter, the open-loop and/or closed-loop control device being set up to generate an exhaust gas atmosphere capable of exothermal reaction in said oxidation catalytic converter by the metering of hydrocarbons into the exhaust gas upstream of said oxidation catalytic converter during a heating operation, wherein the open-loop and/or closed-loop control device is set up to form a first numerical measurement value of a nominal value of a hydrocarbon conversion in said oxidation catalytic converter, to determine a second numerical measurement value of an actual value of the hydrocarbon conversion in said oxidation catalytic converter as a function of the signals of the first temperature sensor, to compare the second numerical measurement value with the first numerical measurement value and to reduce the metering of the hydrocarbons if said second numerical measurement value is smaller than the first numerical measurement value.
Dependencies are inferred from the claim text.