To always perform stable combustion even if deterioration by variation with age of an intake valve or the like is present and PCI combustion is adopted.
Based on actual machine operation data comprising an operation amount by a controller obtained at trial operation, an operation state observation value and a combustion characteristic amount calculated based on a measurement value from an in-cylinder pressure sensor, a forecasting model equation for presuming each of a PM concentration forecasting value 108, a NOx concentration forecasting value 106, a Pmax forecasting value 102 and PmiCOV 104 is previously prepared, and a combustible area map is prepared based on the restriction condition that a permitted range of a value calculated by the forecasting model equation is determined. When the combustion point calculated by the actual machine operation data is relatively displaced in a direction out of the combustible area map, two or more of parameters selected from a fuel injection amount 78, a fuel injection timing 80, an intake valve opening degree 82, an EGR ratio 92 and an air/fuel ratio 94 are varied, and the combustion point is corrected/controlled so as to be relatively returned to an inner side of the combustible area.
MURAKAMI KUNIAKI
CHIBA JUNICHI
NOMURA MASUMI
NAKAYAMA YOSHIHIRO
