METHOD FOR PREPARING THE START UP OF AN INTERNAL COMBUSTION ENGINE BY MEANS OF A BELT DRIVEN STARTER GENERATOR

摘要

The invention relates to a method for preparing the start up of an internal combustion engine (300) by means of a belt driven starter generator (100) which has a stator winding (11) and a rotor winding (12) wherein the starter generator (100) is operated such that the generated torque thereof gradually increases over a duration of more than two rotor winding time constants. Current is fed to the stator winding (11) in such a manner that the generated torque gradually increases over a duration of more than two rotor winding time constants. Current is fed to the rotor winding (12) and if an excitation current through the rotor winding (12) is below a lower threshold before the current feed the stator winding (11) is fed with current before the excitation current is above an upper threshold. According to the invention the belt of the starter generator is pretensioned prior to the actual starting process by means of actuation of the electrical machine and thus lurches vibrations and noises that occur during the start up of the internal combustion engine by means of a starter generator can be prevented.