Control apparatus of internal combustion engine

A control apparatus of an internal combustion engine provided with at least one combustion chamber and at least one fuel injector for injecting fuel to supply the fuel to said combustion chamber, wherein the control apparatus comprises an electronic control unit which memorizes:

• a base position corresponding to a heat release rate gravity position to be acquired when a first injection for injecting a predetermined first amount of a fuel from said fuel injector is normally carried out;
• and
• a base rate corresponding to a heat release rate corresponding to one of said heat release rate gravity position and a heat release rate gravity point to be acquired when said first injection is normally carried out,
• said electronic control unit being configured:
• to acquire any of a combination of a cylinder pressure and a crank angle, and an ion current generated due to combustion of the fuel used in determining the heat release rate expressing an operation state of said engine;
• to calculate said heat release rate gravity position on the basis of the heat release rate;
• to carry out said first injection when a required load of said engine is zero;
• to calculate a gravity position correction coefficient for correcting a reference position corresponding to said heat release rate gravity position when said first injection is carried out such that said reference position corresponds to said base position;
• to calculate a heat release rate correction coefficient for correcting a reference rate corresponding to said heat release rate when said first injection is carried out such that said reference rate corresponds to said base rate;
• to carry out:
• a correction process for correcting said heat release rate gravity position by said gravity position correction coefficient when said required load is larger than zero, and
• a correction process for correcting said heat release rate gravity position by said heat release rate correction coefficient when said required load is larger than zero;
• and
• to control said corrected heat release rate gravity position to a target position by changing at least one combustion parameter for controlling a combustion state in said combustion chamber of said engine when said required load is larger than zero.