Vehicle control system

A vehicle control system, comprising:

• a first motor;
• a differential mechanism including a first rotary element connected to the first motor, a second rotary element connected to drive wheels, and a third rotary element connected to a rotary shaft;
• a second motor that applies a drive force to a power transmitting route between the differential mechanism and the drive wheels;
• a locking mechanism that selectively stops a rotation of the rotary shaft;
• and
• a controller that controls power outputs of the first motor and the second motor,
• wherein the locking mechanism is adapted to keep stopping the rotation of the rotary shaft when a torque of the rotary shaft is smaller than a predetermined torque, and to allow the rotary shaft to rotate when the torque of the rotary shaft is larger than a predetermined torque, and
• wherein the controller is configured to
• estimate an input torque from the drive wheels based on a condition of a road on which the vehicle is currently travelling or on a planned route on which the vehicle is going to travel, when the vehicle is powered by the first motor and the second motor while stopping the rotation of the rotary shaft,
• determine an operating point of the first motor in such a manner as to increase the power output from that of a case in which the estimated input torque is smaller than the predetermined torque, and an operating point of the second motor in such a manner as to decrease the power output from that of a case in which the estimated input torque is smaller than the predetermined torque, in a case that a change rate of a rotational speed of the drive wheel or a predetermined rotary member in the powertrain is greater than a predetermined value, or in a case that a difference between:
• an actual torque applied to the predetermined;
• and an expected torque applied to the predetermined rotary member calculated based on output torques of the first motor and the second motor, is greater than a predetermined value, and
• operate the first motor and the second motor at the determined operating points.