Study On The Modeling And Simulation Of Electronically Controlled Marine Diesel Engine

With the development of electronics, marine diesel engine gradually realizes the control and management of electronic, information and intelligent. The electronic control technology can greatly reduce diesel emissions and improve the economy and reliability of the diesel engine.Volumetric model can be used to the simulation of control system with fast calculation speed and high accuracy. Based on the modularization theory a marine diesel engine model is established by using MATLAB/SIMULINK. The model describes working process of diesel engine, intake and exhaust systems, intercooler, turbocharger, governor, torque output and multi-cylinder model. Cylinder working process uses multi-cylinder model, thereby reducing the amount of calculation and speeding up the simulation.Electric control unit and its control strategy is the key of the electronically controlled diesel engine. A high pressure common rail fuel system is established to realize the PID control of rail pressure, and injection quantity and injection timing control. Two combustion processes including economy mode and low NOx mode (pre-injection mode) are studied and compared, of which two kinds indicator diagram are simulated. The model improves the calculation of the exhaust valve lift, which can still be obtained by using look-up table method accordance with the time.The results show that the modified volumetric diesel engine model, the main parameters and the formulation of MAP is correct, and the model can predict dynamic performance of the diesel engine. As compared with experimental results, the model has smaller relative error, which can be used to analyze and predict the characteristic parameters, and has guiding significance for establishment of the control strategy, initial MAP formulation as well as the last parameter calibration.The electronically controlled diesel engine model can be applied to the marine simulator after using MATLAB to verify its validity. The paper simulates and designs interactive interface of the model in C#. The model can meet the simulation and training requirements to marine simulator with good simulation accuracy and good real-time performance.