Elektronisk motorstyrning för ottomotorer

Sammanfattning: The combustion engines in today’s vehicles are getting more and more advanced and there are increasing demands on that the engines should operate during optimal conditions. Examples of internal combustion engine parameters which may be carefully controlled are the rate between fuel and air, that this gas mixture is homogenous enough and that it is ignited at the correct moment. Moreover, the requirements of these parameters vary depending on, among other, engine speed and load. To meet these requirements in all occurring operation conditions, it is required that many subsystems work together. An important subsystem is the engine management system. This project is about electronic engine management, basically it implies that the engine is controlled by a microcontroller. To manage this, the microcontroller is connected to different sensors and actuators. The project is separated into two parts. The first part is based on theoretical studies of internal combustion engines, obtained results from this area is later used as background material for studies of electrical engine management. The focus lies on the overall function and the technologies which are used of the different components. In the second part a comparison of the basic versions of the electronic engine management systems Motronic and Trionic, developed by Bosch and Saab respectively, is made. This comparison is mainly based on differences between the components used in the different systems. It was found that there are significant differences in how the ignition systems work out. The two main differences are how high-voltage pulses are produced and how a special art of misfiring, knocking, is detected.