Speed change control system for vehicle
AssigneeToyota Jidosha Kabushiki Kaisha
InventorKen Kuretake
Life of this patent
Estimating the term…
Abstract
A speed change control system that suppress a change in a vehicle behavior, and prevents a reduction in an energy efficiency. The speed change control system is applied to a vehicle comprising: a transmission; a wheel connected to the transmission; a motor in which torque or speed is changed by changing a speed ratio of the transmission; and an electric storage device connected to the motor. A controller is configured to select a first mode if an SOC level of an electric storage device is lower than a predetermined level, and select a second mode if the SOC level of the electric storage device is equal to or higher than the predetermined level.
Claims5
A speed change control system for a vehicle, comprising:
- a transmission;
- a drive wheel that is connected to the transmission;
- a motor in which at least any one of a torque and a speed is changed by changing a speed ratio of the transmission;
- and
- an electric storage device that is connected to the motor,
- wherein the speed change control system comprises a controller that controls the transmission, and
- wherein the controller is configured to:
- select a shifting mode of the transmission from a first mode in which a speed ratio of the transmission is changed in accordance with an operating condition of the vehicle, and a second mode in which the speed ratio of the transmission is fixed to a predetermined ratio,
- select the first mode in a case that a state of charge level of the electric storage device is lower than a predetermined level, and select the second mode in a case that the state of charge level of the electric storage device is equal to or higher than the predetermined level,
- select the shifting mode of the transmission from a normal shifting mode in which the speed ratio of the transmission is controlled in accordance with a vehicle speed and a required drive force in such a manner that a system efficiency is optimized, and a seamless mode in which the speed ratio of the transmission is controlled in such a manner that a change in a behavior of the vehicle is reduced, wherein the seamless mode includes the first mode and the second mode, and the first mode includes a mode in which at least any one of the speed ratios available in the normal shifting mode is inhibited,
- calculate an increasing amount of an energy loss resulting from propelling the vehicle in the seamless mode,
- calculate a difference between an amount of regenerative energy by the motor in a case of maintaining the current speed ratio during deceleration of the vehicle, amount of regenerative energy by the motor in a case of changing the speed ratio of the transmission to increase the regenerative energy,
- allow execution of a speed change operation of the transmission during deceleration of the vehicle in a case that the difference between the regenerative energies is greater than the increasing amount of the energy loss, and
- inhibit execution of a speed change operation of the transmission during deceleration of the vehicle in a case that the difference between the regenerative energies is smaller than the increasing amount of the energy loss.
Dependencies are inferred from the claim text.