earticle

영어

Fuel ratio (FR) is the mass ratio of air and fuel trapped inside a cylinder before combustion begins, and it affects engine emissions, fuel economy, and other performances. For a dual fuel engine equipped with both port-fuel-injection (PFI) and direct injection (DI) systems, the fuel ratio is the ratio of the first fuel and total fuel masses. In this research, a multi-input-multi-output baseline chattering free sliding mode methodology scheme is developed with guaranteed stability to simultaneously control fuel ratios to desired levels under various air flow disturbances by regulating the mass flow rates of engine PFI and DI injection systems. A baseline estimator with varying parameter gain is designed with guaranteed stability to allow implementation of the proposed state feedback sliding mode methodology into a MATLAB simulation environment, where the sliding mode strategy is implemented into a model engine control module (“software”). The baseline sliding methodology performance was compared with a well-tuned baseline multi-loop PID controller through MATLAB simulations and showed improvements, where MATLAB simulations were conducted to validate the feasibility of utilizing the developed controller and state estimator for automotive engines. A baseline sliding mode tracking methodology is developed to regulate the transient and steady state FR based upon a control oriented model of the engine PFI wall wetting dynamics. The proposed tracking method is designed to optimally track the desired FR by minimizing the error between the trapped in-cylinder mass and the product of the desired FR and fuel mass over a given time interval. The performance of the optimal proposed tracking methodology was compared with the conventional fueling control based on the inverse fueling dynamics through simulations and showed improvement over the baseline conventional inverse fueling dynamics methodology.