Patent ID: 8388494
Filing Date: 2013-03-05
Classification: B60K,B60W,B60Y,F16H,Y02T,Y10T

Abstract:
1. A method of controlling a hybrid drive-train of a motor vehicle, in which the hybrid drive-train comprises an internal combustion engine (VM) with a driveshaft ( 2 ), an electric machine (EM) that is operable at least as a motor and which has a rotor ( 3 ) that is connectable to the driveshaft ( 2 ) of the internal combustion engine (VM) by an automated separator clutch (K 0 ), an automated powershift transmission (LSG, LSG′) with an input element ( 4 , 4 ′) which is in driving connection with the rotor ( 3 ) of the electric machine (EM), and with at least two frictional shifting elements (K 1 , K 2 ; K 1 ′, K 2 ′) for time-overlapped shifting between two gears, such that during electric driving operation with the internal combustion engine (VM) stopped and the separator clutch (K 0 ) disengaged, the internal combustion engine (VM) can be drag-started in combination with a downshift in the powershift transmission (LSG, LSG′), the method comprising the following steps: disengaging a frictional shifting element (K_ab) to be disengaged to below its slipping limit; engaging the separator clutch (K starting the internal combustion engine (VM); partially disengaging the separator clutch (K separately adjusting the internal combustion engine (VM) and the electric machine (EM) to a synchronous speed (n fully disengaging the frictional shifting element (K_ab) to be disengaged and fully engaging a frictional shifting element (K_zu) to be engaged and the separator clutch (K