Modeling And Simulation Of An Automotive Diesel Engine Cranking System

Abstract

This master thesis is a study of the starting system for a diesel engine and its components. Theories for each component were presented and models were derived for a complete starting system. Focus lied on the starter motor and the losses in the diesel engine, and the models were implemented in the simulation environment Saber. The starter motor model consists of a permanent magnet direct current (PMDC) motor with additional parts which complete the starter motor. The loss components in the engine were manly derived from theoretical equations but also by measured data. The components were used as building blocks and put together to the entire engine losses model. Measurements of the starting system were done and compared with the model s simulation results for different temperatures. The simulated average engine speed is approximately 20 % less than the measured.