Method for determining the rotor angular position of a rotating electrical machine

Abstract

A method is disclosed for determining the rotor angular position of a rotating electrical machine, which machine has a set of stator windings and a set of rotor windings, and in which method the set of stator windings is fed by an associated converter unit. First, the set of stator windings is then short-circuited at at least three predeterminable short-circuiting times by means of the converter unit within one revolution of the rotor given an assumed speed of the rotor. Then, the phase angle of the respective stator current is determined at each short-circuiting time, a differential phase angle being formed from phase angles determined at in each case two temporally adjacent short-circuiting times. Then, the minimum differential phase angle is determined from the differential phase angles, in the event of a negative minimum differential phase angle, a correction phase angle being added to the most recently determined phase angle, and, in the event of a positive minimum differential phase angle, the correction phase angle being subtracted from the most recently determined phase angle.