Patent ID: 7971665

Claim:
A hybrid drive system for a motor vehicle, comprising: an internal combustion engine having a drive shaft and an engine management system; and at least one speed-controlled electric machine coupled to the drive shaft of the internal combustion engine during idling; means for determining overall power demands of an electrical system of the motor vehicle during idling, wherein the electrical system of the motor vehicle includes all electrically operated units of the motor vehicle; a pre-control unit for converting the overall power demands of the electrical system of the motor vehicle during idling into a setpoint torque of the internal combustion engine; wherein, during idling, the engine management system controls the internal combustion engine in one of open and closed loop as a function of the overall power demands of the electrical system of the motor vehicle; wherein during idling the internal combustion engine is speed-controlled with the aid of the electric machine; wherein a power output of the internal combustion engine is adjusted to an instantaneous overall power demand of the electrical system of the motor vehicle; and wherein the setpoint torque of the internal combustion engine is determined as a function of the instantaneous overall power demand of the electrical system of the motor vehicle, and at least one of an injection quantity, an air quantity, and an ignition angle of the internal combustion engine is adjusted according to the determined setpoint torque.