Patent ID: 8109856

Claim:
A method of operating a drivetrain ( 1 ) of a vehicle during thrust operation, the drivetrain comprising an internal combustion engine ( 2 ), an electric machine ( 3 ) and a transmission device ( 4 ), the electric machine ( 3 ) being located in a force flow between the combustion engine ( 2 ) and the transmission device ( 4 ) and a shift element ( 8 ), with a continuously variable transmission capacity, being located between the electric machine ( 3 ) and a drive output ( 5 ) such that a nominal output torque (m_fahr_soll) delivered to the drive output ( 5 ) is a function of the transmission capacity of the shift element ( 8 ), the method comprising the steps of: adjusting the transmission capacity of the shift element ( 8 ), in a controlled manner as a function of the nominal output torque (m_fahr_soll), such that the transmission capacity of the shift element ( 8 ) is as required for delivering the nominal output torque (m_fahr_soll) to the drive output ( 5 ); adjusting a speed (n_ 3 ) of the electric machine ( 3 ), in a controlled manner during a shut-off process of the combustion engine ( 2 ), to maintain the shift element ( 8 ) in a slipping operation at least during the process of shutting off the combustion engine ( 2 ); and reducing a speed of the combustion engine ( 2 ) to zero, via the electric machine ( 3 ).