Particulate accumulation amount estimating system

A particulate accumulation amount estimating system comprising:

• a pressure difference detecting section configured to detect a pressure difference across a particulate filter that is configured and arranged to capture particulate matter contained in exhaust gas discharged from an engine;
• an ash accumulation amount estimating section configured to estimate an ash accumulation amount of ash accumulated in the particulate filter;
• an effective area determining section configured to determine
• a change in an effective area of the particulate filter resulting from the ash accumulated in the particulate filter based on the estimated value of the ash accumulation amount,
• a pressure loss rate corresponding to a change in the effective area, and
• an accumulated ach portion of the pressure difference that was detected due to the accumulated ash based on the estimated value of the ash accumulation amount;
• and
• a particulate accumulation amount estimating section configured to
• estimate a particulate accumulation amount of particulate matter accumulated in the particulate filter based on an amended pressure difference and the effective area change that was determined, the amended pressure difference resulting from amending the pressure difference based on the pressure loss rate, and
• calculate an accumulated particulate matter portion of the detected pressure difference due to the accumulated particulate matter by subtracting the accumulated ash portion of the detected pressure difference resulting from the accumulated ash from the amended pressure difference.

A particulate accumulation amount estimating system comprising:

• a pressure difference detecting section configured to detect a pressure difference across a particulate filter that is configured and arranged to capture particulate matter contained in exhaust gas discharged from an engine;
• an ash accumulation amount estimating section configured to estimate an ash accumulation amount of ash accumulated in the particulate filter;
• an effective area determining section configured to determine a change in an effective area of the particulate filter resulting from the ash accumulated in a particulate filter based on the estimated value of the ash accumulation amount;
• and
• a particulate accumulation amount estimating section configured to estimate a particulate accumulation amount of particulate matter accumulated in the particulate filter based on the pressure difference that was detected and the effective area change that was determined,
• the particulate accumulation amount estimating section being further configured to change an estimation characteristic used to estimate the particulate accumulation amount to a pressure difference increase characteristic when the particulate accumulation amount is increasing and a pressure difference decrease characteristic when the particulate accumulation amount is decreasing.

A particulate accumulation amount estimating system comprising:

• a pressure difference detecting section configured to detect a pressure difference across a particulate filter that is configured and arranged to capture particulate matter contained in exhaust gas discharged from an engine;
• an ash accumulation amount estimating section configured to estimate an ash accumulation amount of ash accumulated in the particulate filter;
• an effective area determining section configured to determine a change in an effective area of the particulate filter resulting from the ash accumulated in the particulate filter based on the estimated value of the ash accumulation amount;
• and
• a particulate accumulation amount estimating section configured to estimate a particulate accumulation amount of particulate matter accumulated in the particulate filter based on the pressure difference that was detected and the effective area change that was determined,
• the ash accumulation amount estimating section further configured to amend the estimated value of the ash accumulation amount based on a detected frequency with which the particulate filter has been subjected to a vehicle traveling condition in which ash accumulates inside a wall of the particulate filter, the ash accumulation amount estimating section determining that the vehicle traveling condition exists when the particulate accumulation amount is below a prescribed amount and when a temperature of at least one of the particulate filter and the exhaust gas is equal to or above a prescribed temperature.