Patent ID: 8554399

Claim:
A method for operating a drive train of a motor vehicle, the drive train having a hybrid drive that comprises an internal combustion engine, an electric motor, an electrical energy storage means and a transmission, the method comprising: measuring an actual charge state of the electrical energy storage means; measuring data indicative of an instantaneous driving state of the motor vehicle and independent of any anticipatory data from a navigation apparatus; determining a setpoint charge for the electrical energy storage means based on the measured data indicative of the instantaneous driving state of the motor vehicle; comparing the measured actual charge state of the electrical energy storage means to the setpoint charge state for the electrical energy storage means; determining one of several operating modes for the drive train as a function of the comparison of the actual charge state and the setpoint charge state; and shifting range boundaries or range extents of the operating modes as a function of the setpoint charge state; and shifting a load point of the internal combustion engine to lowering the load point and to discharge the electrical energy storage means when the setpoint charge state of the electrical energy storage means is less than the actual charge state of said electrical energy storage means.