Patent ID: 7669583

Claim:
An internal combustion engine control apparatus comprising: heat release amount information acquisition means for acquiring heat release amount information about an internal combustion engine; relationship information acquisition means for acquiring relationship information, which is derived from a first relationship information and a second relationship information, and which is information about in-cylinder pressure at least one crank angle other than a combustion start time and a combustion end time, and the first relationship information indicates in-cylinder combustion ratio information about the internal combustion engine in accordance with the heat release amount information at the combustion start time, the heat release amount information at the combustion end time, and the heat release amount information at said at least one crank angle, and the second relationship information indicates the in-cylinder combustion ratio information in accordance with a Weibe function including the combustion start time, the combustion end time, and a combustion speed as a parameter; and pressure estimation means for estimating the in-cylinder pressure in accordance with the relationship information.