Modeling and control of a Gasoline Direct Injection fuel system

Fuel economy and emissions are the two main concerns to many automobile engineers. The Gasoline Direct Injection (GDI) fuel systems are widely used in internal combustion engines to improve fuel economy with reduced emissions.;This study focuses on the development of a MotoTron based fuel rail pressure control system. This work is motivated by the need for maintaining higher fuel rail pressure for improved fuel injection accuracy. The developed fuel rail control system consists of a MotoTron control module, a customized actuator drive box, and a host computer with LabVIEW GUI (graphic user interface) and the MotoTune calibration tool for MotoTron. The MotoTron and the host computer communicate through CAN (control area network). A mathematical model of the fuel rail control system was developed using MATLAB/Simulink.;The pressure controller for the fuel system contains three parts: a bumpless and anti-windup PI (proportional and integral) controller, a feed-forward controller, and a dead-zone compensator. The closed-loop control was simulated and validated in Simulink using the developed model, where the fuel injection process was also considered. The simulation results of tracking the desired pressure were compared with the experiment data.;The comparison with the Simulink simulation results and experiment data shows that the Simulink model is able to reflect the characteristics of the actual fuel rail system; and the experiment data show that the closed-loop controller is able to maintain the fuel system pressure at the desired level.