A vehicle driving force control apparatus is configured to provide a
vehicle drive force control apparatus that can expand the operating
region within which an electric motor can be driven in a stable manner.
The output of an engine is delivered to the main drive wheels through a
transmission and also to an electric generator. The output voltage of the
electric generator is supplied to the electric motor and the output of
the electric motor drives the subordinate drive wheels. When it is
determined that the generator output voltage will not be sufficient to
meet the requirement of the electric motor, the amount of acceleration
slippage allowed at the left and front wheels is increased.