Patent ID: 8316635
Filing Date: 2012-11-27
Classification: F01N,Y02T

Abstract:
1. A method of compensating for measurement inaccuracies in a filter, the method comprising: after a regeneration period of a regeneration on the filter, determining an estimate of removable particulate matter loading remaining in the filter after the period, wherein the regeneration on the filter is a procedure that is intended to eliminate removable particulate matter from the filter, wherein the regeneration is active during the regeneration period, and wherein the regeneration is active when the procedure that is intended to eliminate removable particulate matter from the filter is in operation; and determining a first disparate value by quantifying a difference between: wherein the regeneration on the filter is repeated until at least one predetermined criteria is met, wherein whether to repeat the regeneration is based on the predetermined criteria, wherein the determination of whether at least one predetermined criteria is net is made at an end of the regeneration period when the regeneration is inactive, and wherein the regeneration is inactive when the procedure that is intended to eliminate removable particulate matter from the filter is not in operation, the predetermined criteria being used to indicate when a sufficient amount of removable particulate matter has been eliminated, wherein the predetermined criteria is met when: (1) a percentage of time during a regeneration period in which a filter inlet temperature meets or exceeds a targeted temperature is above a predefined threshold; and (2) a percentage of time during the regeneration period in which a volumetric flow rate through the filter meets or exceeds a requested flow rate is above a predefined threshold.