| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a reducing agent injection control device and a control method of a reducing agent injection device, making correction so that the actual injection quantity of a reducing agent is optimized, and an exhaust emission control device of an internal combustion engine including the reducing agent injection control device. <P>SOLUTION: This reducing agent injection control device includes: a required injection quantity computing part for calculating a required injection quantity of a reducing agent based on parameter values including NO<SB>X</SB>discharged at least from the internal combustion engine, the temperature of a reduction catalyst and an adsorption quantity of ammonia in the reduction catalyst; a reducing agent injection control part for injecting the reducing agent from the reducing agent injection device according to the required injection quantity; an injection quantity abnormality determination part for determining abnormality of the actual injection quantity of the reducing agent by comparing the sensor value of a specific gas concentration sensor provided on the downstream side of the reduction catalyst and sensitive to at least NO<SB>X</SB>and ammonia with a predetermined threshold; and an injection quantity computing parameter value correction part for correcting the parameter values of the required injection quantity computing part when abnormality of the actual injection quantity occurs. <P>COPYRIGHT: (C)2010,JPO&INPIT |
