Controller of a vehicle power transmission system

Control apparatus for a vehicular power transmission system, the power of an engine (8) to a drive wheel (34) transmits, said control device comprising: an electric differential unit (11) that allows controlling a differential state between a rotational speed of an input shaft (14) which is coupled to the engine (8), and a rotational speed of an output shaft by controlling an operating state of an electric motor (M1, M2) with a rotary element of a differential mechanism (16) is coupled; and a transmission unit (20) which is disposed in a power transmission path between the electric differential unit (11) and the drive wheel (34), characterized, in that comprises the control unit further comprises a machine upper limit setting means (86) from the start of a switching operation of the transmission unit (20) up to the beginning of a torque reduction control by the electric motor (M1, M2) an upper limit (N a determination of whether ...