Development of an Electronic Fuel Injection System for Two Stroke SI Engine Using Virtual Instrumentation

At present, the modern vehicles are embedded with Electronic Fuel Injection (EFI) system for better fuel economy and reduced emission. But the automation software used in this system is not user friendly because of preset program based μP control. To overcome these difficulties, in the present paper, it has been proposed for an interactive EFI system for Spark Ignition (SI) engines. It has been replaced μP based software and hardware structures with a modern client/server solution. On the client side, the virtual instrumentation software program used for data acquisition. The fuel map and time maps are generated for the various operating conditions of the engine. For the mapping, the visualization tool is used in 3-d plot. From the mapping, the fuel injection time and fuel delivery quantity is estimated for the required running condition of the engine. The system that has been designed accesses the data using interfaces. As a result, users can easily create company and field specific extension because of the openness of the client solution. Users can also store their analysis results directly in the data server through interfaces. Various sensors have been used through RS-232 port to sense the parameters such as manifold depression, angular position of throttle valve and engine speed. These data were used in the analysis for delivering the output such as quantity of fuel injected and start of injection etc,. The program can be developed in several modes and the user can choose any mode during operation of the vehicle according to the requirements. Thus, the interface used has simplified the implementation and reduced project time and cost compared to a conventional solution.