Patent ID: 8352106

Claim:
A method for operating a power-branching hybrid drive of a vehicle having a first electric machine, a second electric machine and an internal combustion engine outputting a torque, wherein the first and second electric machines are coupled via a transmission, the method comprising: connecting drives of the internal combustion engine, the first electric machine and the second electric machine; at least intermittently controlling a) operation of the first electric machine by rotation-speed regulation and b) operation of the second electric machine by torque regulation; controlling operation of the internal combustion engine by rotation-speed regulation; and performing, based on a first system deviation between a setpoint rotation speed and an actual rotation speed of the internal combustion engine, a torque intervention in the internal combustion engine, wherein the setpoint rotation speed of the internal combustion engine is specified, and a setpoint rotation speed of the first electric machine is calculated based on the setpoint rotation speed of the internal combustion engine.