Fuel Parameters Estimation and Control Adaptation for Spark-ignition Engine

Alternative fuels create a variation of fuel properties for spark-ignition engines between different geographical areas, or even inside Europe, with the introduction of biofuels. It has an impact on the engine performance, particularly in terms of consumption and knock resistance. In order to preserve an optimal engine operation facing these dispersions, this paper proposes an adaptation of the classical structure of the SI engine control, taking into account the main fuel parameters. Two issues have to be addressed: firstly, the online estimation of these parameters and secondly, the engine control adaptation in order to maintain a relevant torque response while optimizing consumption and preventing engine knock. The main claim of this work is to improve the robustness of the engine control while limiting the calibration effort by use of analytic models of combustion.