System and method of controlling engine clutch engagement during TCS operation of hybrid vehicle

Patent metadata

Field	Value
Publication number	US-10399559-B2
Application number	US-201615363824-A
Country	US
Kind code	B2
Filing date	Nov 29, 2016
Priority date	Aug 26, 2016
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

A system and method of controlling engine clutch engagement during TCS operation of a hybrid vehicle are provided. The method includes determining whether a TCS is operating and upon determining that the TCS is operating, determining a compensation value for early engagement of an engine clutch during the TCS operation based on a difference between a front wheel speed and a rear wheel speed and a slip amount of front wheels. Additionally, the method includes determining whether engagement of the engine clutch is capable of being started based on the compensation value and starting the engine clutch engagement. Since the engagement of the engine clutch is controlled based on the speed of non-drive wheels during TCS operation, the engagement stability of the engine clutch is improved and the amount of time required to engage the engine clutch is decreased.

First claim

What is claimed is:

1. A method of controlling engine clutch engagement during traction control system (TCS) operation of a hybrid vehicle, comprising:
determining, by a high-level controller of the hybrid vehicle, whether a TCS is operating;
in response to determining that the TCS is operating, determining, by the high-level controller, a compensation value for engine clutch engagement control during the TCS operation based on a difference between a front wheel speed and a rear wheel speed and a slip amount of front wheels;
determining, by the high-level controller, whether engagement of the engine clutch is capable of being started based on the compensation value and starting the engine clutch engagement; and
engaging, by an engine electronic control unit (ECU), the engine clutch in response to receiving an engine clutch engagement control signal from the high-level controller.

2. The method of claim 1 , wherein the determination of the compensation value for engine clutch engagement control during the TCS operation includes:
calculating, by the high-level controller, the difference between the front wheel speed and the rear wheel speed; and
comparing, by the high-level controller, the difference with the slip amount of the front wheels.

3. The method of claim 2 , wherein, as the difference between the front wheel speed and the rear wheel speed increases to be greater than the slip amount of the front wheels, the compensation value increases, and as the difference between the front wheel speed and the rear wheel speed decreases to be less than the slip amount of the front wheels, the compensation value decreases.

4. The method of claim 1 , wherein the determination of whether the engagement of the engine clutch is capable of being started includes:
comparing, by the high-level controller, a difference between an engine speed and a motor speed, the motor speed being the front wheel speed, with a sum of a relative speed that enables the engine clutch engagement and the compensation value; and
when the difference between the engine speed and the motor speed is less than the sum of the relative speed and the compensation value, determining, by the high-level controller, that engagement of the engine clutch is capable of being started.

5. The method of claim 1 , further comprising:
after determining whether the engagement of the engine clutch is capable of being started based on the compensation value, determining, by the high-level controller, whether it is possible to prevent engine stall before starting the engine clutch engagement.

6. The method of claim 5 , wherein the determination of whether it is possible to prevent the engine stall includes:
comparing, by the high-level controller, a rear motor speed represented by an input shaft speed that is calculated based on the rear wheel speed with an engine stall-preventing engine speed set based on the rear wheel speed; and
when the rear motor speed is greater than the engine stall-preventing engine speed, determining, by the high-level controller, that it is possible to prevent the engine stall.

7. A system of controlling engine clutch engagement during traction control system (TCS) operation of a hybrid vehicle, comprising:
a memory configured to store program instructions; and
a processor configured to execute the program instructions, the program instructions when executed configured to:
determine whether a TCS is operating;
determine a compensation value for engine clutch engagement control during the TCS operation based on a difference between a front wheel speed and a rear wheel speed and a slip amount of front wheels in response to determining that the TCS is operating;
determine whether engagement of the engine clutch is capable of being started based on the compensation value and starting the engine clutch engagement; and
engage the engine clutch based on a signal transmitted to an engine electronic control unit (ECU).

8. The system of claim 7 , wherein the program instructions when executed that determine the compensation value for engine clutch engagement control during the TCS operation are further configured to:
calculate the difference between the front wheel speed and the rear wheel speed; and
compare the difference with the slip amount of the front wheels.

9. The system of claim 8 , wherein, as the difference between the front wheel speed and the rear wheel speed increases to be greater than the slip amount of the front wheels, the compensation value increases, and as the difference between the front wheel speed and the rear wheel speed decreases to be less than the slip amount of the front wheels, the compensation value decreases.

10. The system of claim 7 , wherein the program instructions when executed that determine whether the engagement of the engine clutch is capable of being started are further configured to:
compare a difference between an engine speed and a motor speed, the motor speed being the front wheel speed, with a sum of a relative speed that enables the engine clutch engagement and the compensation value; and
determine that engagement of the engine clutch is capable of being started when the difference between the engine speed and the motor speed is less than the sum of the relative speed and the compensation value.

11. The system of claim 7 , wherein the program instructions when executed are further configured to:
determine whether it is possible to prevent engine stall before starting the engine clutch engagement after determining whether the engagement of the engine clutch is capable of being started based on the compensation value.

12. The system of claim 11 , wherein the program instructions when executed that determine whether it is possible to prevent the engine stall are further configured to:
compare a rear motor speed represented by an input shaft speed that is calculated based on the rear wheel speed with an engine stall-preventing engine speed set based on the rear wheel speed; and
determine that it is possible to prevent the engine stall when the rear motor speed is greater than the engine stall-preventing engine speed.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Cho Teh Hwan
• Kim Sang Joon
• Du Gwang Il
• Kang Ji Hoon
• Park Seong Ik

Classifications

• B60K6/442 Primary

  Series-parallel switching type · CPC title

• F16D2500/70426

  Clutch slip · CPC title

• F16D2500/5075

  Prevention or regulation of vehicle's wheel slip · CPC title

• F16D2500/5048

  Stall prevention · CPC title

• F16D2500/3115

  Vehicle wheel speed · CPC title