Cylinder Pressure-based Combustion Control with Multi-pulse Fuel Injection

With an increased number of fuel injection pulses, the control problem in diesel engines becomes complex. Consisting of multiple single-input single-output (SISO) controllers, the conventional control strategy shows unsatisfactory dynamic performance in tracking combustion load and phase reference metrics. In this paper, a general framework is discussed that describes the combustion process on a cycle-to-cycle basis with parametrized fueling profiles. It provides a systematic approach for combustion controller design with multi-pulse fuel injection since the correlated influence of changing individual fuel injection pulses is explicitly considered. Based on a sensitivity analysis, a multi-input multi-output (MIMO) combustion controller is designed with local stability guarantee. It shows faster and decoupled tracking performance compared with the conventional (SISO) combustion controller in a numerical simulation based on a validated engine model.