| 摘要 |
PROBLEM TO BE SOLVED: To improve combustion stability at the time of laminated combustion operation by detecting a combustion parameter which represents a fuel ignition lag from in-cylinder pressure detected by an in-cylinder pressure detection means, and correcting ignition timing so that the combustion parameter may be within a set value at the time of laminated combustion operation. SOLUTION: In the light-load area of an engine, laminated combustion operation is conducted, in which fuel is injection-supplied into the second half of a compression stroke from a fuel injector 27, and lean air-fuel mixture is formed in a cylinder as a whole while forming air-fuel layer in the vicinity of an ignition plug 23. On the other hand, in the heavy-load area, homogeneous combustion operation is conducted, in which fuel is injection-supplied from the fuel injector 27 into an intake stroke, and the air-fuel ratio of the cylinder as a whole is formed so as to be uniform. At the time of the laminated combustion operation, ignition timing is calculated based on an ignition timing map from an engine rotational speed, an intake air amount and so on, and by reading in-cylinder pressure detected by an in-cylinder pressure sensor 24, and obtaining a combustion parameter, the ignition timing is corrected so that the combustion parameter may be within a set value. |
