Patent ID: 8826884

Claim:
Method for controlling combustion in a multi-cylinder internal combustion engine operating in a controlled auto-ignition mode, comprising: determining a respective peak cylinder pressure and a respective crank angle location of the peak cylinder pressure for each cylinder during each combustion cycle; determining a respective cylinder volume at the respective crank angle location of the peak cylinder pressure for each cylinder during each combustion cycle; determining a respective cylinder pressure at a respective intake valve closing for each cylinder during each combustion cycle; determining a respective cylinder volume at the respective intake valve closing for each cylinder during each combustion cycle; calculating an instantaneous combustion parameter for each cylinder based upon the respective peak cylinder pressure, the respective cylinder pressure at the respective intake valve closing, the respective crank angle location of the respective peak cylinder pressure, the respective cylinder volume at the respective crank angle location of the peak cylinder pressure, and the respective cylinder volume at the respective intake valve closing; providing unmodified combustion control parameters which are identical in each cylinder; determining a target combustion parameter to be maintained in each cylinder based upon the provided unmodified combustion control parameters and the calculated instantaneous combustion parameters for each cylinder, wherein the unmodified combustion control parameters provided for determining the target combustion parameter correspond to a combustion cycle immediately subsequent to a present combustion cycle at which the instantaneous combustion parameters are calculated for determining the target combustion parameter; comparing the calculated instantaneous combustion parameter for each cylinder in the present combustion cycle to the target combustion parameter; individually adjusting the provided unmodified combustion control parameters in each respective cylinder to balance the calculated instantaneous combustion parameter across all cylinders in the immediately subsequent combustion cycle based on the comparing, wherein the individually adjusted provided unmodified combustion control parameters in each respective cylinder only affects the calculated instantaneous combustion parameter for the respective cylinder being adjusted; and controlling the engine during the immediately subsequent engine cycle based on the individually adjusted provided combustion control parameters.