Patent ID: 8177680

Claim:
A control system for a drive unit of a vehicle, which has an electrically controlled speed change unit electrically controlling a speed change ratio thereof governed by an input revolution and an output revolution, and a mechanically controlled speed change unit mechanically changing a gear stage thereof governed by an input revolution and an output revolution; and in which a speed change mode can be selected from a first speed change mode wherein a total speed change ratio governed by the speed change ratio of the electrically controlled speed change unit and the gear stage of the mechanically controlled speed change unit is set on the basis of a running condition of a vehicle, and a second speed change mode wherein the total speed change ratio is set on the basis of a signal for applying a power source braking, the control system comprising: a gear stage limiting means for reducing a number of settable gear stages of the mechanically controlled speed change unit in case the second speed change mode is selected; an electric storage device storing mechanical energy resulting from running of the vehicle in the form of electric power; an electric motor to which the electric power is fed from the electric storage device, and which outputs power for running; a state of charge determining means for determining a state of charge of the electric storage device in case the downshift signal for increasing the total speed change ratio is outputted to apply the power source braking; and a charge expediting means for setting a high speed side gear stage of the mechanically controlled speed change unit in case the state of charge determining means determines that a charging capacity of the electric storage device is low, wherein the total speed change ratio is set according to the gear stage of the mechanically controlled speed change unit set by the gear stage limiting means, and to the speed change ratio of the electrically controlled speed change unit, in case the second speed change mode is selected, so as to equalize an amount of charge and an amount of discharge of the electric storage device, in case the state of charge determining means determines that the charging capacity is high.