Operate a drive train by short-term active short circuit

摘要

The invention relates to a method for operating an electric drive train with an electrical energy store (8), a converter (16) and an electric machine (14) for driving a motor vehicle, by disconnecting an electrical connection between the converter (16) and the electrical Energy storage (8), initiating an active short circuit by shorting a winding of the electric machine (16) and determining a current flow associated with the winding. In order to avoid the occurrence of both high voltages and high currents in the electrical machine and / or the converter when opening the separating element (10), the active short-circuit of the winding is interrupted when the current flow assigned to it makes a zero crossing.