Patent ID: 7267191

Claim:
A method for controlling a hybrid powertrain system for an automotive vehicle operated by a user, the system having an engine, an electric machine that performs as a motor in one mode of operation and performs as a generator in another mode of operation, a battery connected to the electric machine, and a generator configured to receive mechanical power from the engine and to present electrical power to at least one of the electric machine and the battery, and at least one of the engine and the electric machine establish a power source for providing power to vehicle traction wheels, the method comprising the steps of: determining a first power state of the hybrid powertrain system; limiting electrical power generated by the generator to the minimum of the rated power limit of the generator and the first power state, when the first power state is greater than zero; and limiting the electrical power generated by the generator to zero, and limiting the power limit of the electric machine during generating to a first operating condition of the hybrid powertrain system, when the first power state is less than or equal to zero, to provide over-charge protection to the battery.