Study On Engine Fuel Injection Control System Based On Model

Model-based design approach is a kind of new method for the development of embedded system. When we use this method to design the embedded system, the development time and the system cost will be obviously reduced. The electronic control system of engine is a type of complicated embedded control system, which is especially fit for making use of the model-based design approach to design. In this article, we discuss how to use this method to design the fuel injection control system of the engine.We make comprehensive analysis and summary to the model-based design approach. Then we point out that the most important feature of this method is that the automatic code generation technology is adopted, which benefits the reduction of development time and system cost. Finally, we summarize that the most important process of this method is to create the plant and the controller model.According to the engine operating feature, we make out the control strategy of injection system. In stable operating condition we adopt close-loop control and in transient condition we use open-loop control based on manifold pressure observer and fuel dynamic compensator and in idle speed condition we employ the fuzzy—PI(D) controller to maintain the stable engine speed.We establish the engine model and make simulation trials on the model. Creating the model, we firstly divide the engine into several subsystems according to their functions. Then we establish mathematic equations to describe the dynamics of these subsystems. Finally we set up the model of these subsystems based on these equations and combine the established subsystems into the engine model. After creating the model, we make some simulation trials and the results prove that the model can perfectly simulate the dynamics of the real engine system.Also we make the controller model and test the main control module though simulation trials. Creating the controller model, we firstly divide the controller into three task modules and a scheduler module. Then we begin to design control algorithm for each control module and create their models. When we complete themodel of all control modules, we make testing trials on the engine model and the results prove that the established control modules are satisfactory.