Hybrid vehicle, controller for hybrid vehicle, and control method for hybrid vehicle with a change of the switching conditions from a depleting mode to a sustaining mode

A controller for a hybrid vehicle, the hybrid vehicle including an internal combustion engine, an electrical storage device and a rotary electric machine,

• the internal combustion engine including a variable valve actuating device configured to change an operation characteristic of an intake valve,
• the electrical storage device being configured to be charged, and
• the rotary electric machine being configured to generate driving force for propelling the hybrid vehicle by using electric power that is supplied from the electrical storage device,
• the controller comprising:
• a mode control unit configured to
• change a switching condition for switching from the a charge depleting mode to the a charge sustaining mode such that a first state of charge is higher than a second state of charge,
• the first state of charge being a state of charge at which the controller switches from the charge depleting mode to the charge sustaining mode at the time when the operation characteristic of the intake valve is unchangeable to a desired operation characteristic,
• the second state of charge being a state of charge at which the controller switches from the charge depleting mode to the charge sustaining mode at the time when the operation characteristic of the intake valve is changeable to the desired operation characteristic, and
• select one of the charge sustaining mode and the charge depleting mode;
• and a traveling control unit configured to cause the hybrid vehicle to travel in the mode selected by the mode control unit,
• the charge sustaining mode being a mode in which a state of charge of the electrical storage device is kept within a predetermined range, and
• the charge depleting mode being a mode in which consumption of the state of charge is given a higher priority as compared to the charge sustaining mode.

A control method for a hybrid vehicle, the hybrid vehicle including an internal combustion engine, an electrical storage device, a rotary electric machine and a controller,

• the internal combustion engine including a variable valve actuating device configured to change an operation characteristic of an intake valve,
• the electrical storage device being configured to be charged, and
• the rotary electric machine being configured to generate driving force for propelling the hybrid vehicle by using electric power that is supplied from the electrical storage device, the control method comprising:
• changing, by the controller, a switching condition for switching from the a charge depleting mode to the a charge sustaining mode such that a first state of charge is higher than a second state of charge, the first state of charge being a state of charge at which the controller switches from the charge depleting mode to the charge sustaining mode at the time when the operation characteristic of the intake valve is unchangeable to a desired operation characteristic, the second state of charge being a state of charge at which the controller switches from the charge depleting mode to the charge sustaining mode at the time when the operation characteristic of the intake valve is changeable to the desired operation characteristic;
• and
• causing, by the controller, the hybrid vehicle to travel in a selected one of the charge sustaining mode and the charge depleting mode, the charge sustaining mode being a mode in which a state of charge of the electrical storage device is kept within a predetermined range, the charge depleting mode being a mode in which consumption of the state of charge is given a higher priority as compared to the charge sustaining mode.