In order to improve the accuracy and steadiness of rail pressure

modeling and optimizing of rail pressure control strategy were completed through the Matlab/Simulink. A double-level closed-loop control algorithm based on rail pressure signal and current signal of fuel meter valve was designed to enhance the control accuracy degenerated by actuators. A feed-forward control model was adopted to make transient response better. Finally the optimized control strategy was demonstrated with diesel fuel injection pump bench test and engine bench test. The result shows that the rail pressure deviation is within ±0.5 MPa at stable condition and within ±(2~5) MPa at transient condition

meeting the requirements of domestic common rail pressure control systems.