METHOD FOR PERFORMING ROTATIONAL SPEED SYNCHRONISATION

A method for performing rotational speed synchronisation of a first transmission component having a first initial rotational speed with a second transmission component having a second initial rotational speed, by means of a three-phase AC electric motor that is rotationally connected to the first transmission component, during a gear switch in a stepped gear transmission of a drive train having a switching mechanism enabling the stator windings of the AC electric motor to be selectively connected in star configuration or delta configuration. The method includes obtaining a command, or determining, that a gear switch should be performed; shifting the stator winding configuration of the AC electric motor to delta configuration, or ensuring that the stator winding configuration of the AC electric motor is in delta configuration; and controlling operation of the AC electric motor for accomplishing rotational speed synchronisation of the first and second transmission components.