CONTROL DEVICE FOR HYBRID VEHICLE

• US 20090120700A1
• Filed: 11/06/2008
• Published: 05/14/2009
• Est. Priority Date: 11/08/2007
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: FUKUMURA, Mitsumasa
• Granted Patent: US 7,950,485 B2
• Time in Patent Office: Days
• US Class Current: 180/65.265
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/115 with planetary gears
• 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 20/30 Control strategies involving selection of transmission gear ratio control of change speed gearings, together with other vehicle sub-units B60W10/10; HEV transmission gearing B60K6/36; gearings and control thereof F16H
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: F16H 2037/0866 Power split variators with distributing differentials, with the output of the CVT connected or connectable to the output shaft
• CPC Class Codes: F16H 2200/2007 with two sets of orbital gears
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

The control device for the hybrid vehicle is mounted on the hybrid vehicle including the engine and the motor generator as the driving source and capable of switching at least two modes, i.e., the infinite variable speed mode and the fixed gear ratio mode. When the speed change is performed from the infinite variable speed mode to the fixed gear ratio mode, the first speed change control to maintain the number of revolutions equal to or larger than the number of engine revolutions at the time of setting the infinite variable speed mode and reduce the engine torque to shift the speed gear in the fixed gear ratio mode is executed. Thereby, when the speed change is performed from the infinite variable speed mode to the fixed gear ratio mode, it becomes possible to appropriately suppress the drivability deterioration caused due to the change of the number of engine revolutions.

Claims

1. A control device for a hybrid vehicle which comprises an engine and a motor generator as a driving source, and which switches at least two modes:

an infinite variable speed mode; and

a fixed gear ratio mode, comprising;

a speed change control unit which executes a first speed change control that maintains a number of revolutions equal to or larger than a number of engine revolutions at a time of setting the infinite variable speed mode, and reduces an engine torque to change to the fixed gear ratio mode, when the speed change is performed from the infinite variable speed mode to the fixed gear ratio mode.

2. The control device for the hybrid vehicle according to claim 1, further comprising a speed change determination unit which predicts a future operation state and determines whether or not to execute the first speed change control based on the predicted operation state,

wherein, only when the speed change determination unit determines to execute the first speed change control, the speed change control unit executes the first speed change control.

3. The control device for the hybrid vehicle according to claim 2,

wherein, when an operation state does not become the operation state predicted by the speed change determination unit during executing the first speed change control, the speed change control unit stops the execution of the first speed change control, and executes a second speed change control that moves an operation point of the engine on a fuel consumption optimum line and an equipower line to change to the fixed gear ratio mode.

4. The control device for the hybrid vehicle according to claim 1,

wherein the speed change control unit sets the number of engine revolutions so that a difference between numbers of revolutions of engaging components used for switching the infinite variable speed mode and the fixed gear ratio mode becomes substantially 0, and executes the first speed change control.

5. A control device for a hybrid vehicle which comprises an engine and a motor generator as a driving source, and which switches at least two modes:

an infinite variable speed mode; and

a fixed gear ratio mode, comprising;

a speed change control unit which executes a first speed change control that maintains a number of revolutions equal to or larger than a number of engine revolutions at a time of setting the fixed gear ratio mode, and increases an engine torque to change to the infinite variable speed mode, when the speed change is performed from the fixed gear ratio mode to the infinite variable speed mode.

6. The control device for the hybrid vehicle according to claim 5, further comprising a speed change determination unit which predicts a future operation state and determines whether or not to execute the first speed change control based on the predicted operation state,

wherein, only when the speed change determination unit determines to execute the first speed change control, the speed change control unit executes the first speed change control.

7. The control device for the hybrid vehicle according to claim 6, wherein, when an operation state does not become the operation state predicted by the speed change determination unit during the execution of the first speed change control, the speed change control unit stops the execution of the first speed change control, and executes a second speed change control that moves an operation point of the engine on a fuel consumption optimum line and an equipower line to change to the fixed gear ratio mode.