Method for starting up an internal combustion engine

Abstract

A method is provided for starting up an internal combustion engine in a drive train using a torque of a multi-pole electric motor which is torque-transmittingly connected to the internal combustion engine, encoderlessly operated and has a rotor that can be rotated relative to a stator and to which a co-rotating QD-coordinate system is assigned. A rotor rotational speed of the rotor is increased from a resting rotor and, during this starting process of the rotor, in the D-direction, a first excitation voltage is applied at the electric motor, which is greater than a comparison excitation voltage by an electrical additional voltage, which is applied under the same conditions at the electric motor during a starting process of the electric motor omitting a starting-up of the internal combustion engine.

Dependencies are inferred from the claim text.