Patent ID: 7587889
Filing Date: 2009-09-15
Classification: F01N,F02B,F02D,Y02T

Abstract:
1. A system for determining a NOx conversion efficiency of an exhaust gas aftertreatment component coupled to an internal combustion engine, comprising: means for determining an operating temperature of the exhaust gas aftertreatment component, and a control circuit including a memory having instructions stored therein that are executable by the control circuit to determine a time duration that the operating temperature of the exhaust gas aftertreatment component is above a predefined temperature, and to determine the NOx conversion efficiency of the exhaust gas aftertreatment component as a function of the time duration, the memory further having stored therein a conversion model of the NOx conversion efficiency of the exhaust gas aftertreatment component as a function of the time duration and a multiplier model producing a multiplier as a function of at least one operating parameter that is different from the operating temperature of the exhaust gas aftertreatment component, and wherein the instructions executable by the control circuit include instructions to determine an initial value of the NOx conversion efficiency of the exhaust gas aftertreatment component, as a function of the time duration, according to the conversion model and to multiply the initial value of the NOx conversion efficiency by the multiplier to determine the NOx conversion efficiency of the exhaust gas afterireatment component.