CONTROL SYSTEM AND CONTROL METHOD FOR HYBRID VEHICLE

• US 20140148985A1
• Filed: 11/21/2013
• Published: 05/29/2014
• Est. Priority Date: 11/24/2012
• Status: Abandoned Application

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: KUWAHARA, Seiji, SATO, Shun, SUGIMURA, Toshio, TSUTSUMI, Takahiko, MINAMIKAWA, Koki
• Application Number:
  US14/086,379
• Publication Number:
  US 20140148985A1
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 30/18127 Regenerative braking
• CPC Class Codes: B60W 30/186 excessive wear or burn out of friction elements, e.g. clutches
• CPC Class Codes: B60W 30/19 Improvement of gear change, e.g. by synchronisation or smoothing gear shift
• CPC Class Codes: F16H 63/50 Signals to an engine or motor
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor

Abstract

A control system for a hybrid vehicle includes a controller. When a downshift of a transmission and an increase in an amount of regeneration are carried out during regenerative coast traveling in which regeneration is carried out by an electric motor, and when a state of charge of a battery is lower than a predetermined value, the controller increases the amount of regeneration before completion of the downshift. When the state of charge of the battery is higher than or equal to the predetermined value, the controller increases the amount of regeneration after completion of the downshift.

Claims

1. A control system for a hybrid vehicle, comprising:

an engine serving as a driving force source;

an electric motor serving as a driving force source;

a transmission provided on a power transmission path between a drive wheel and both the engine and the electric motor;

a battery configured to exchange electric power with the electric motor; and

a controller configured to, when a downshift of the transmission and an increase in an amount of regeneration are carried out during regenerative coast traveling in which regeneration is carried out by the electric motor and when a state of charge of the battery is lower than a predetermined value, increase the amount of regeneration before completion of the downshift, the controller being configured to, when the state of charge of the battery is higher than or equal to the predetermined value, increase the amount of regeneration after completion of the downshift.

2. The control system according to claim 1, wherein

the controller is configured to, when the amount of regeneration is increased before completion of the downshift and when the state of charge of the battery is low, extend a period of time from an increase in the amount of regeneration to completion of the downshift as compared to that when the state of charge of the battery is high.

3. A control method for a hybrid vehicle, the hybrid vehicle including an engine and an electric motor, each of which serves as a driving force source, a transmission provided on a power transmission path between a drive wheel and both the engine and the electric motor, and a battery configured to exchange electric power with the electric motor, the control method comprising:

starting a downshift of the transmission during regenerative coast traveling in which regeneration is carried out by the electric motor;

detecting a request to increase an amount of regeneration carried out by the electric motor;

determining whether a state of charge of the battery is higher than or equal to a predetermined value; and

increasing the amount of regeneration before completion of the downshift when the state of charge of the battery is lower than the predetermined value, and increasing the amount of regeneration after completion of the downshift when the state of charge of the battery is higher than or equal to the predetermined value.

4. The control method according to claim 3, wherein

when the amount of regeneration is increased before completion of the downshift and when the state of charge of the battery is low, a period of time from an increase in the amount of regeneration to completion of the downshift is extended as compared to that when the state of charge of the battery is high.