PM EMISSION AMOUNT ESTIMATION DEVICE FOR DIESEL ENGINE

摘要

The PM emission amount and accumulation amount in all operation states including a transition state and a steady state are precisely estimated by increasing the correcting precision of a base value of the PM emission amount obtained from a PM emission amount map, thereby specifically making it possible to precisely calculate the PM emission amount in the transition state. A PM emission amount estimation device for a diesel engine having a DPF which collects PM discharged from an exhaust passage is provided with a base PM emission amount map (3) for calculating a base emission amount of PM in accordance with the operation state of the engine, a PM emission amount correction map (5) for calculating a correction coefficient used to correct the base PM emission amount calculated using the base PM emission amount map (3) in accordance with the transition state, a transition state detection means (7) for detecting the transition state from a change in an excess air ratio of the engine, and a PM emission amount calculation means (9) for correcting the base PM emission amount using the correction coefficient from the PM emission amount correction map (5) only when the transition state is detected by the transition state detection means (7) and for outputting the base PM emission amount directly in the case of the steady state.