System and method for monitoring a particulate filter in a vehicle exhaust aftertreatment device

摘要

A method of monitoring a particulate filter of an exhaust aftertreatment device includes sensing a first pressure drop across the particulate filter at a first instant in time, and sensing a second pressure drop across the particulate filter at a second instant in time. A controller may then calculate a rate-of-change of the pressure drop between the first instant in time and the second instant in time while sensing a flow rate of an exhaust gas flowing through the exhaust aftertreatment device. Using the sensed exhaust flow rate, the controller may determine a rate-of-change threshold, and subsequently compare the calculated rate-of-change to the rate-of-change threshold. The method further includes updating a soot model using the sensed second pressure drop if the calculated rate-of-change is less than the rate-of-change threshold.

主权项

1. A method of regenerating a particulate filter of an exhaust aftertreatment device comprising:
sensing a first pressure drop across the particulate filter at a first instant in time via a pressure sensor; sensing a second pressure drop across the particulate filter at a second instant in time via the pressure sensor, wherein the first instant in time and the second instant in time are from 0.5 to 60 seconds apart; calculating a rate-of-change of the pressure drop between the first instant in time and the second instant in time using a controller in communication with the pressure sensor; sensing a flow rate of an exhaust gas flowing through the exhaust aftertreatment device; determining a rate-of-change threshold from the sensed exhaust flow rate; comparing the calculated rate-of-change to the rate-of-change threshold; updating a soot model maintained by the controller using the sensed second pressure drop if the calculated rate-of-change is less than the rate-of-change threshold; and regenerating the particulate filter when an amount of soot, as determined by the soot model, exceeds a soot threshold, wherein the regenerating includes burning the soot off the particulate filter by heating the particulate filter via increasing an amount of fuel provided to an engine coupled.