Control apparatus, exhaust purifying apparatus for internal combustion engine, and control method for exhaust purifying apparatus

• Main Author: Tanioka, Kenichi
• Format: Patent
• Language: English
• Published: 21.08.2018
• Subjects: BLASTING; ENGINE PLANTS IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; HEATING; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; LIGHTING; MACHINES OR ENGINES IN GENERAL; MEASURING; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PHYSICS; SEPARATION; STEAM ENGINES; TESTING; TRANSPORTING; WEAPONS

A control apparatus that includes a measured NOx purification ratio calculation unit calculating a measured NOx purification ratio of a reduction catalyst based on outputs of NOx sensors and provided upstream and downstream of the reduction catalyst reducing nitrogen oxide in an exhaust gas, an estimated NOx purification ratio calculation unit calculating an estimated NOx purification ratio of the reduction catalyst based on a temperature of the reduction catalyst, a flow rate of the exhaust gas, and an absorption amount of the reducing agent by the reduction catalyst, and a reducing agent concentration estimation unit estimating a concentration of the reducing agent injected from a reducing agent injection valve based on the measured NOx purification ratio and the estimated NOx purification ratio.