Modeling and Control Strategy Research on Diesel Engine HighPressure Common Rail System

To achieve precise control of rail pressure and enhance the performance of a diesel engine, a feedforward + sliding mode active disturbance rejection control (F-SMADRC) algorithm is proposed. Focusing on a six-cylinder high-pressure common rail diesel engine, the mathematical models of its fuel metering unit, high-pressure fuel pump, common rail pipe, and fuel injector are derived. An experimental design is implemented to identify the parameters and validate the accuracy of the controlled object model. Finally, the proposed control algorithm is validated on the Simulink simulation platform, including testing its control effectiveness under both steady-state and transient conditions. A comparative evaluation is conducted against traditional PID and ADRC algorithms, considering performance metrics such as overshoot, response time, and absolute error. Additionally, the adaptive and anti-interference capabilities of the algorithm are explored under conditions of injector nozzle blockage, sudden changes in engine speed and fuel injection pulse width. Simulation results demonstrate that the proposed control algorithm exhibits minimal fluctuations in steady-state conditions, low overshoot and fast response time in transient conditions, effectively regulating rail pressure, and possessing robustness and adaptive capabilities.