Abstract: A traveling mode setting unit configured to cause a shift to shift to a second traveling mode via a third traveling mode based on a traveling state of the vehicle traveling in the first traveling mode. The internal combustion engine control unit includes a derivation unit configured to derive a second rotational speed of the internal combustion engine at the time of transition from the third traveling mode to the second traveling mode based on a first rotational speed of the internal combustion engine at the time of transition from the first traveling mode to the third traveling mode, the traveling state of the vehicle and the second reduction ratio, and the internal combustion engine control unit is configured to control a third rotational speed of the internal combustion engine in the third traveling mode to be a value between the first rotational speed and the second rotational speed.

Abstract: A traveling mode setting unit configured to cause a shift to shift to a second traveling mode via a third traveling mode based on a traveling state of the vehicle traveling in the first traveling mode. The internal combustion engine control unit includes a derivation unit configured to derive a second rotational speed of the internal combustion engine at the time of transition from the third traveling mode to the second traveling mode based on a first rotational speed of the internal combustion engine at the time of transition from the first traveling mode to the third traveling mode, the traveling state of the vehicle and the second reduction ratio, and the internal combustion engine control unit is configured to control a third rotational speed of the internal combustion engine in the third traveling mode to be a value between the first rotational speed and the second rotational speed.

Abstract: A hybrid electric vehicle including a gradient acquiring portion which acquires a gradient of a road surface on which the vehicle is running, and a control portion which determines whether the vehicle runs on a first driving by means of power from the motor by releasing the engagement and disengagement portion, or on a second driving by means of power from at least the internal combustion engine by applying the engagement and disengagement portion. The control portion restricts a switch from the second driving to the first driving when the gradient of the downward slope is equal to or greater than a threshold value. The control portion holds the second driving when the switch from the second driving to the first driving is restricted, even though the control portion obtains a request for a switch to the first driving while the vehicle runs the downward slope on the second driving.

Abstract: A hybrid electric vehicle including a gradient acquiring portion which acquires a gradient of a road surface on which the vehicle is running, and a control portion which determines whether the vehicle runs on a first driving by means of power from the motor by releasing the engagement and disengagement portion, or on a second driving by means of power from at least the internal combustion engine by applying the engagement and disengagement portion. The control portion restricts a switch from the second driving to the first driving when the gradient of the downward slope is equal to or greater than a threshold value. The control portion holds the second driving when the switch from the second driving to the first driving is restricted, even though the control portion obtains a request for a switch to the first driving while the vehicle runs the downward slope on the second driving.