IN-CYLINDER PRESSURE ESTIMATION DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

The cylinder pressure estimation device of the invention is applied to an engine which has a cylinder pressure sensor 63 and comprises means for calculating as candidate values of an intake-valve-closing-time cylinder pressure, a plurality of candidate values of a possible cylinder pressure at an intake-valve-closing time T2, means for calculating as candidates of a cylinder pressure movement, a plurality of candidates of a possible movement of the cylinder pressure from the intake-valve-closing time T2 to a post-intake-valve-closing time T3 on the basis of the candidate values of the intake-valve-closing-time cylinder pressure, means for calculating as a detected cylinder pressure movement, a movement of the cylinder pressure detected by the cylinder pressure sensor from the intake-valve-closing time T2 to the post-intake-valve-closing time T3; and means for comparing the candidates of the cylinder pressure movement with the detected cylinder pressure movement, determining the candidate of the cylinder pressure movement to be deemed to correspond to the detected cylinder pressure movement among the candidates of the cylinder pressure movement and determining as the cylinder pressure at the intake-valve-closing time, the candidate value of the intake-valve-closing-time cylinder pressure used for calculating the determined candidate of the cylinder pressure movement.