Modelling and Operational Testing of Pulse-width Modulation at Injection Time for a Spark-ignition Engine

Original scientific paper Nowadays, the computer control has to be taken into account in any field of study. Due to the advantage of its binary system, it can very quickly control the signals from devices. This paper is focused on the analysis of some studies carried out on the PWM (Pulse Width Modulation) technologies. The engines used nowadays are provided with an electronic injection system. During our research, we have made a connection between a few parameters which contribute to the increase of the engine performance. Our team has used the PWM, a common technique employed for controlling power to inertial electrical devices, in order to show the benefits of the injection time control; the results regarding the engine management have been very good. We have taken into account a few parameters such as pressure, battery voltage, lambda signals, fuel and air amount, etc., as well as their time evolution, with the help of the ECU control. Using the MATLAB/Simulink software, we have managed to control, by using the pulse width modulation, the reference speed, the throttle position, as well as other parameters and data collected from the tests carried out on Dacia Logan 1.4 MPI (powered by Renault), and the evolution of the injection time. By creating a PWM signal, we can precisely control the injection time.