Mode control apparatus of hybrid vehicle and control method thereof

• US 9,862,369 B2
• Filed: 12/07/2014
• Issued: 01/09/2018
• Est. Priority Date: 02/17/2014
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.)
• Inventors: Park, Joonyoung, Kim, Tae Woo, Park, Song-Il
• Primary Examiner(s): Khatib, Rami
• Assistant Examiner(s): Wiltey, Nicholas K
• Application Number:
  US14/562,736
• Publication Number:
  US 20150232080A1
• Time in Patent Office: 1,129 Days
• Field of Search: None
• CPC Class Codes: B60K 2006/4825 Electric machine connected or connectable to gearbox input shaft
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• 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 10/113 with two input flow paths, e.g. double clutch transmission selection of one of the torque flow paths by the corresponding input clutch
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 2510/0241 Clutch slip, i.e. difference between input and output speeds
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/1015 Input shaft speed, e.g. turbine speed
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/902 Prime movers comprising electrical and internal combustion motors

Abstract

A mode control apparatus of a hybrid vehicle is provided. The apparatus includes a first clutch that is disposed between an engine and a motor generating power and a second clutch that is disposed between the motor and a transmission. In addition, a controller is configured to execute engagement and disengagement of the first clutch and the second clutch. The controller is also configured to adjust the speed of the motor and the transmission to be synchronized by generating slip in the second clutch when a transition from an EV mode to an HEV mode is requested.

Claims

1. A mode control apparatus of a hybrid vehicle, comprising:

a first clutch disposed between an engine and a motor generating power;

a second clutch disposed between the motor and a transmission; and

a controller configured to execute engagement and disengagement of the first clutch and the second clutch,

wherein the controller is configured to adjust a speed of the motor and the engine to be synchronized by generating slip in the second clutch when a transition from an electric vehicle (EV) mode to a hybrid electric vehicle (HEV) mode is requested,

wherein the EV mode is a mode that disengages the first clutch and engages the second clutch, and drives the vehicle using the motor driving torque,

wherein the HEV mode is a mode that engages the first clutch and the second clutch, and drives the vehicle using the motor driving torque and the engine driving torque,

wherein the controller is configured to start the engine, operate the second clutch to slip by reducing coupling force of the second clutch, operate the first clutch to be engaged after synchronizing an engine speed and a motor speed, and operate the second clutch to be fully engaged when the input speed of the transmission is greater than a minimum engine speed, when the transition from the EV mode to the HEV mode is requested in a state where an input speed of the transmission is less than a minimum speed of the engine, and

wherein the engagement of the first clutch is prohibited before the engine speed is synchronized with the motor speed.

2. The mode control apparatus of the hybrid vehicle of claim 1,

wherein the controller is configured to operate the second clutch to be released, operate the first clutch to be engaged by starting the engine, operate the second clutch to slip by increasing coupling force of the second clutch, and operate the second clutch to be fully engaged when input speed of the transmission is greater than a minimum engine speed, when the transition from the EV mode to the HEV mode is requested and when the motor cannot be used.

3. The mode control apparatus of the hybrid vehicle of claim 1,

wherein the controller is configured to start the engine while maintaining engagement of the second clutch, and operate the first clutch to be engaged after synchronizing the engine speed and the motor speed, when the transition from the EV mode to the HEV mode is requested and when an input speed of the transmission is greater than a minimum speed of the engine.

4. A mode control method of a hybrid vehicle, comprising:

determining, by a controller, whether a transition from an electric vehicle (EV) mode to a hybrid electric vehicle (HEV) mode is requested;

determining, by the controller, whether an input speed of a transmission is zero;

determining, by the controller, whether the input speed of the transmission is greater than a minimum engine speed, when the input speed of the transmission is greater than zero;

generating, by the controller, slip of a second clutch disposed between a motor and a transmission by reducing a coupling force of the second clutch and maintaining an engine in an idle state after starting the engine, when an input speed of the transmission is less than the minimum engine speed;

determining, by the controller, whether the engine speed is synchronized with the motor speed;

engaging, by the controller, a first clutch disposed between the engine and the motor when the engine speed and the motor speed are synchronized; and

fully engaging, by the controller, the second clutch when the input speed of the transmission is greater than the minimum engine speed,

wherein the engagement of the first clutch is prohibited before the engine speed is synchronized with the motor speed.

5. The mode control method of the hybrid vehicle of claim 4, further comprising:

operating, by the controller, the second clutch to be released by reducing coupling force of the second clutch, operating the first clutch to be engaged, starting the engine using the motor or an additional starting motor, and operating the second clutch to cause slip by increasing coupling force of the second clutch, when the input speed of the transmission is zero;

determining, by the controller, whether the input speed of the transmission is greater than the minimum engine speed; and

fully engaging, by the controller, the second clutch when the input speed of the transmission is greater than the minimum engine speed.

6. The mode control method of the hybrid vehicle of claim 4, further comprising:

synchronizing, by the controller, the engine speed with the motor speed after starting the engine while maintaining engagement of the second clutch; and

engaging, by the controller, the first clutch after synchronizing the engine speed and the motor speed when the input speed of the transmission is greater than zero and the input speed of the transmission is greater than the minimum engine speed.

7. A non-transitory computer readable medium containing program instructions executed by a controller, the computer readable medium comprising:

program instructions that determine whether a transition from an electric vehicle (EV) mode to a hybrid electric vehicle (HEV) mode is requested;

program instructions that determine whether an input speed of a transmission is zero;

program instructions that determine whether the input speed of the transmission is greater than a minimum engine speed, when the input speed of the transmission is greater than zero;

program instructions that generate slip of a second clutch disposed between a motor and a transmission by reducing a coupling force of the second clutch and maintaining an engine in an idle state after starting the engine, when an input speed of the transmission is less than the minimum engine speed;

program instructions that determine whether the engine speed is synchronized with the motor speed;

program instructions that engage a first clutch disposed between the engine and the motor when the engine speed and the motor speed are synchronized; and

program instructions that fully engage the second clutch when the input speed of the transmission is greater than the minimum engine speed,

wherein the engagement of the first clutch is prohibited before the engine speed is synchronized with the motor speed.

8. The non-transitory computer readable medium of claim 7, further comprising:

program instructions that operate the second clutch to be released by reducing coupling force of the second clutch, operate the first clutch to be engaged, start the engine using the motor or an additional starting motor, and operate the second clutch to cause slip by increasing coupling force of the second clutch, when the input speed of the transmission is zero;

program instructions that determine whether the input speed of the transmission is greater than the minimum engine speed; and

program instructions that fully engage the second clutch when the input speed of the transmission is greater than the minimum engine speed.

9. The non-transitory computer readable medium of claim 7, further comprising:

program instructions that synchronize the engine speed with the motor speed after starting the engine while maintaining engagement of the second clutch; and

program instructions that engage the first clutch after synchronizing the engine speed and the motor speed when the input speed of the transmission is greater than zero and the input speed of the transmission is greater than the minimum engine speed.