Vehicle control apparatus and vehicle control method

A vehicle control apparatus for a vehicle,

• the vehicle including an engine and a motor,
• the engine including at least one cylinder, a valve and a crankshaft, the valve being configured to control flow of air out of and into the at least one cylinder, and
• the motor being configured to adjust a crank angle of the crankshaft by outputting a torque to the crankshaft,
• the vehicle control apparatus comprising an electronic control unit configured to:
• perform feedback control of the motor, during stop control of the engine, based on the crank angle such that the torque is output for stopping the crankshaft at a target angle corresponding to the crank angle at which the valve is in a closed-valve state;
• detect a rotational direction of the crankshaft;
• use a first gain, during a first period, as a motor gain that prescribes a magnitude of the torque,
• the first period being a period from start of the feedback control to a timing of first detection of rotation of the crankshaft in a negative rotational direction for returning the crank angle, which has become larger than the target angle, toward the target angle;
• use a second gain as the motor gain during a second period,
• the second period being a period from lapse of the first period to a timing of detection of a changeover in a rotational direction of the crankshaft from the negative rotational direction to a positive rotational direction, and
• the second gain being a gain that prescribes a larger torque in the positive rotational direction than the first gain;
• and
• return the motor gain from the second gain to the first gain at a first timing,
• the first timing being a timing when the crank angle, which has become smaller than the target angle during the second period, becomes equal to or larger than the target angle after lapse of the second period.

A vehicle control method for a vehicle,

• the vehicle including an engine, a motor and an electronic control unit,
• the engine including at least one cylinder, a valve and a crankshaft, the valve being configured to control flow of air out of and into the at least one cylinder, and
• the motor being configured to adjust a crank angle of the crankshaft by outputting a torque to the crankshaft,
• the vehicle control method comprising:
• performing, by the electronic control unit, feedback control of the motor, during stop control of the engine, based on the crank angle such that the torque is output for stopping the crankshaft at a target angle corresponding to the crank angle at which the valve is in a closed-valve state;
• detecting a rotational direction of the crankshaft;
• using, by the electronic control unit, a first angle as the target angle during a first period,
• the first period being a period from start of the feedback control to a timing of first detection of rotation of the crankshaft in a negative rotational direction for returning the crank angle, which has become larger than the target angle, toward the target angle, and
• the first angle corresponding to the crank angle at which the valve is in the closed-valve state;
• using, by the electronic control unit, a second angle as the target angle during a second period,
• the second period being a period from lapse of the first period to a timing of detection of a changeover in a rotational direction of the crankshaft from the negative rotational direction to a positive rotational direction, and
• the second angle being larger than the first angle, and returning the target angle from the second angle to the first angle at a first timing,
• the first timing being a timing when the crank angle, which has become smaller than the first angle during the second period, becomes equal to or larger than the first angle after lapse of the second period.

A vehicle control method for a vehicle,

• the vehicle including an engine, a motor and an electronic control unit,
• the engine including at least one cylinder, a valve and a crankshaft, the valve being configured to control flow of air out of and into the at least one cylinder, and
• the motor being configured to adjust a crank angle of the crankshaft by outputting a torque to the crankshaft,
• the vehicle control method comprising:
• performing, by the electronic control unit, feedback control of the motor, during stop control of the engine, based on the crank angle such that the torque is output for stopping the crankshaft at a target angle corresponding to the crank angle at which the valve is in a closed-valve state;
• detecting a rotational direction of the crankshaft;
• using, by the electronic control unit, a first gain, during a first period, as a motor gain that prescribes a magnitude of the torque,
• the first period being a period from start of the feedback control to a timing of first detection of rotation of the crankshaft in a negative rotational direction for returning the crank angle, which has become larger than the target angle, toward the target angle;
• using, by the electronic control unit, a second gain as the motor gain during a second period,
• the second period being a period from lapse of the first period to a timing of detection of a changeover in a rotational direction of the crankshaft from the negative rotational direction to a positive rotational direction, and
• the second gain being a gain that prescribes a larger torque in the positive rotational direction than the first gain;
• and
• returning the motor gain from the second gain to the first gain at a first timing,
• the first timing being a timing when the crank angle, which has become smaller than the target angle during the second period, becomes equal to or larger than the target angle after lapse of the second period.