Patent ID: 8246509
Filing Date: 2012-08-21
Classification: B60K,B60L,B60W,Y02T,Y10T

Abstract:
1. A method of operating a drive train of a motor vehicle, the drive train comprising a hybrid drive with an internal combustion engine and an electric motor, a transmission being arranged between the hybrid drive and a drive output, and a clutch being arranged between the internal combustion engine and the electric motor, in which, when only the electric motor is working, the internal combustion engine is started by engaging the clutch between the internal combustion engine and the electric motor, the method comprising the steps of: when, during electric motor powered driving with the electric motor running and the internal combustion engine not operating, carrying out a shift operation in the transmission to change gear with an interruption of the traction force, immediately after the gear change of the shift operation and during a load build-up phase of the shift operation, starting the internal combustion engine with the electric motor without a traction force interruption by engaging and disengaging the clutch, arranged between the internal combustion engine and the electric motor, in a controlled manner such that by being partially engaged the clutch is brought to a slipping condition for starting the internal combustion engine, and then completely disengaging the clutch again before reaching a synchronous speed between the internal combustion engine and the electric motor.