摘要:
A temperature of exhaust gas downstream of an oxidation catalyst is compared to a temperature of the exhaust gas upstream of the oxidation catalyst to determine if the downstream temperature is increasing over time or decreasing over time as hydrocarbons are injected into the flow of exhaust gas to regenerate a particulate filter. The oxidation catalyst is determined to be quenched when the temperature of the exhaust gas downstream of the oxidation catalyst remains constant or decreases over time as the rate at which the hydrocarbons are injected into the exhaust gas increases. The oxidation catalyst is determined to not be quenched when the temperature of the exhaust gas downstream of the oxidation catalyst increases over time as the rate at which the hydrocarbons are injected into the exhaust gas increases.
摘要:
A method of controlling an exhaust gas treatment system for an engine includes relating the usage of an oxidation catalyst to a temperature offset value, and increasing a current burn threshold temperature by the temperature offset value to define an adjusted burn threshold temperature. Hydrocarbons may be injected into a flow of exhaust gas when the temperature of the oxidation catalyst is equal to or greater than the adjusted burn threshold temperature. The temperature at which the hydrocarbons are injected into the exhaust gas is thereby increased to accommodate performance degradation in the oxidation catalyst, which extends the life of the oxidation catalyst.
摘要:
An engine control system comprises an oxygen comparison module and a regeneration control module. The oxygen comparison module compares an oxygen concentration of an exhaust gas of an engine to an oxygen threshold. A regeneration control module initiates regeneration of a particulate filter and controls regeneration based on the oxygen comparison and at least one of a particulate filter load, a particulate filter temperature, and a speed of the engine.
摘要:
A temperature control system comprises a temperature determination module, a temperature correction module, a temperature control module, and an updating module. The temperature determination module determines a desired outlet temperature for an oxidation catalyst (OC) that is located upstream of a particulate filter (PF) in an exhaust system. The temperature correction module determines a temperature correction from a plurality of temperature corrections. The temperature control module controls an outlet temperature of the OC based on the desired outlet temperature and the temperature correction. The updating module selectively updates at least one of the plurality of temperature corrections when an engine speed and an engine load are within respective predetermined ranges.
摘要:
A method controls an exhaust gas temperature from a vehicle engine during regeneration of particulate filter (PF) in a vehicle having an oxidation catalyst (OC) and a selective catalytic reduction catalyst (SCR). The method ensures that a final OC temperature does not exceed a maximum of the target OC outlet temperature and a calibrated maximum OC outlet temperature. An apparatus for controlling a temperature of the exhaust gas includes sensors for measuring a temperature within the exhaust system and a controller having an algorithm, an OC temperature lookup table, and a PF temperature lookup table. The algorithm calculates a target OC outlet temperature using the lookup tables and a delayed error value that compensates for a thermal mass of the SCR. Actual OC outlet temperature is limited during regeneration of the PF to the lesser of the target OC outlet temperature and a calibrated maximum OC outlet temperature.