Patent ID: 7275365

Claim:
A method for controlling temperature in a Diesel particulate filter during regeneration, said Diesel particulate filter being disposed in an exhaust system of a Diesel engine, and said method comprising: determining the amount of particulate matter extant in said Diesel particulate filter; determining the temperature of the Diesel particulate filter in response to determining that regeneration of the Diesel particulate filter is required; sensing at least one engine operating parameter; determining if said engine is operating in an adverse condition conducive to uncontrolled regeneration of the Diesel particulate filter; determining the values of oxygen concentration and mass flowrate of oxygen in exhaust gas passing through the Diesel particulate filter; determining desired values for net oxygen concentration and mass flowrate of exhaust gas passing through said Diesel particulate filter for the sensed at least one operating parameter correlative of engine speed and load, said desired values being values below which uncontrolled regeneration of the Diesel particulate filter will occur, and said net oxygen concentration passing through the Diesel particulate filter includes the convective and diffusion flow of oxygen into the Diesel particulate filter; abruptly reducing the net oxygen concentration of exhaust gas passing through said Diesel particulate filter to a value less than said desired concentration in response to determining that the engine is operating in said adverse condition conducive to uncontrolled regeneration of the Diesel particulate filter; and, abruptly adjusting the exhaust mass flowrate through said Diesel particulate filter to a flowrate at which the mass flowrate of oxygen passing through the Diesel particulate filter is less than said desired mass flowrate of oxygen.