Patent ID: 8831812

Claim:
In a hybrid drivetrain for a motor vehicle, the drivetrain comprising an internal combustion engine; an electric machine; a twin-clutch gearbox having a first friction clutch, a first sub-gearbox, a second friction clutch, and a second sub-gearbox, the first friction clutch and the first sub-gearbox forming a first branch of the twin-clutch gearbox, the second friction clutch and the second sub-gearbox forming a second branch of the twin-clutch gearbox, and the electric machine being coupled to an input shaft of one of the sub-gearboxes; and a controller; in which drivetrain power is provided by the internal combustion engine in a first operating mode and power is provided by the electric machine in a second operating mode, wherein a change from one operating mode into the other operating mode is carried out according to the state of at least one of the drivetrain and the motor vehicle, a method for operating the hybrid drivetrain comprises the step of controlling, in the controller, the change of the operating mode according to at least one switching variable, which is a function of a requested power target value; wherein the switching variable is further a function of a limit power value of the electric machine and the limit power value is a function of at least one limiting factor.