In-cylinder Burned Gas Rate Estimation and Control on VVA Diesel Engines

In this paper, we propose a strategy to control the in-cylinder burned gas rate inside the combustion chambers of turbocharged Diesel engines equipped with low pressure EGR loop and VVA actuator. We first design a mean-value model of the in-cylinder composition and validate it on a high frequency reference simulator. Then, we develop the control strategy. It is based on the coordination of existing low-level controllers acting separately on the EGR valve and on the VVA actuator. The objective is to improve transient response, taking into account the responses of the low-level controllers. Supportive simulation results show the relevance of this approach.