Patent ID: 8001951

Claim:
A method for controlling an internal combustion engine, comprising: providing: an engine block having a cylinder, a crank shaft arranged in the block, a cylinder head arranged on the block opposite the crank shaft, a combustion chamber defined in the cylinder of the block and below the cylinder head, an intake tract connected to the combustion chamber as a function of the position of a gas intake valve, an exhaust gas tract connected to the combustion chamber as a function of the position of a gas discharge valve, and a cylinder pressure sensor that detects a pressure in the combustion chamber; measuring the pressure in the combustion chamber after closing the gas discharge valve and before subsequent opening of the gas intake valve; detecting a plurality of the measured values of the pressure in the combustion chamber; determining a polytropic exponent as a function of the plurality of detected values of the pressure in the combustion chamber; determining an exhaust gas mass in the cylinder after closing the gas discharge valve and before subsequent opening of the gas intake valve as a function of: the polytropic exponent at an estimated value of the pressure after closing the gas discharge valve and before subsequent opening of the gas intake valve, and a temperature of the exhaust gas in the cylinder after closing the gas discharge valve and before subsequent opening of the gas intake valve; and generating an actuation signal for controlling an actuating member of the internal combustion engine as a function of the determined exhaust gas mass.