Patent ID: 7668630

Claim:
An electromechanically power-splitting hybrid drive system for a motor vehicle that includes an internal combustion engine, a first electric motor, a second electric motor, and a transmission coupling the first electric motor and the second electric motor, the hybrid drive system comprising: a control system that, based on a coupling condition of the transmission, calculates respective target rotation speeds and target torques for the internal combustion engine, the first electric motor, and the second electric motor; and a plurality of rotation speed controllers for the internal combustion engine, the first electric motor, and the second electric motor, wherein: the rotation speed controllers compare the calculated target rotation speeds with the pertinent actual rotation speeds, and in the case of a deviation between one of the actual rotation speeds and the pertinent target rotation speed, the rotation speed controllers calculate, on the basis of the deviation, at least one additional torque that are taken into account, in addition to at least one of the target torques calculated by the control system, in controlling the torque of the internal combustion engine, the first electric motor, and the second electric motor.