To efficiently suppress a rise of the temperature of an torque electric machine in a hybrid vehicle.
The hybrid vehicle (10) includes: power elements including an internal combustion engine (200) and the torque electric machine (MG1); a differential mechanism (300) in which a plurality of rotating elements connecting the power elements are configured to mutually perform differential rotation; and a lock mechanism (400) configured to switch a rotating element (304) connected to the rotating electric machine among a plurality of the rotating elements between a locked state and an unlocked state. The control device (100) includes: a control means for controlling the rotating electric machine in such a way that the rotational speed of the rotating electric machine is transited while spending a set transition time since a point of time when the transition is started toward a rotational speed equal to or lower than a prescribed value including a value 0 until the rotational speed reaches a value equal to or lower than the prescribed value including the value 0 when the rotational element is switched from the unlocked state to the locked state; and a changing means for changing the set transition time when predetermined change conditions are established.
Koji Yamamoto
Satoshi Nakamura