Shifting control method for vehicle with dual clutch transmission

Patent metadata

Field	Value
Publication number	US-10589744-B2
Application number	US-201816009563-A
Country	US
Kind code	B2
Filing date	Jun 15, 2018
Priority date	Feb 13, 2018
Publication date	Mar 17, 2020
Grant date	Mar 17, 2020

Abstract

A shifting control method for a vehicle with a dual clutch transmission (DCT), the shifting control method may include controlling engine torque to be increased according to reserve demand torque by giving the reserve demand torque of an engine to be increased to a predetermined value or more when if a controller determines that the vehicle enters a manual power off and downshift shifting; controlling, by the controller, a release side clutch to be released; controlling, by the controller, an engine torque to perform a control so that engine speed follows coupling side input shaft speed; and completing the shifting by performing a control so that a coupling side clutch is coupled when it is determined that the actual shift is completed.

First claim

What is claimed is:

1. A shifting control method for a vehicle with a dual clutch transmission (DCT), the shifting control method comprising:
an initial shift step of controlling an engine torque to be increased according to a reserve demand torque by giving the reserve demand torque of an engine to be increased to a predetermined value or more when a controller determines that the vehicle enters a manual power off and downshift shifting;
a clutch release step of controlling, by the controller, a release side clutch to be released;
an actual shift step of controlling, by the controller, the engine torque so that engine speed follows a coupling side input shaft speed; and
a shift completion step of completing shifting of the DCT by the controller so that a coupling side clutch is coupled when the controller determines that the shifting is completed.

2. The shifting control method of claim 1 , wherein in the initial shift step, the reserve demand torque is set to be in proportion to an amount of slip of the coupling side clutch.

3. The shifting control method of claim 1 , wherein in the clutch release step, a cooperative control demand torque is controlled to 0 Nm.

4. The shifting control method of claim 1 , wherein the actual shift step includes:
a demand torque determination step of determining the reserve demand torque and a cooperative control demand torque of the engine by feeding back a difference between a differential value of a target amount of slip and a differential value of a current amount of slip of the coupling side clutch to a value obtained by multiplying engine inertia and a differential value of an amount of slip of the coupling side clutch; and
an engine torque control step of controlling the engine torque based on the reserve demand torque or the cooperative control demand torque.

5. The shifting control method of claim 4 , wherein the engine torque control step includes:
controlling the engine torque according to the reserve demand torque; and
controlling the engine torque according to the cooperative control demand torque while releasing the reserve demand torque when the engine torque reaches the cooperative control demand torque.

6. The shifting control method of claim 5 , wherein when the engine torque reaches the cooperative control demand torque, the engine torque is controlled based on the cooperative control demand torque, such that the engine speed is converged on the coupling side input shaft speed and the amount of slip of the coupling side clutch is reduced.

7. The shifting control method of claim 1 , wherein in the shift completion step, when a current amount of slip of the coupling side clutch is an amount of synchronization reference slip or less and a target stage gear is coupled, the coupling side clutch is coupled by increasing a coupling side clutch torque to an absolute value or more of a cooperative control demand torque.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp
• Hyundai Motor Compnay

Inventors

• Cho Sung Hyun

Classifications

• B60W2510/0657

  Engine torque · CPC title

• B60W2510/1015

  Input shaft speed, e.g. turbine speed · CPC title

• F16H61/688 Primary

  with two inputs, e.g. selection of one of two torque-flow paths by clutches · CPC title

• B60W2710/021

  Clutch engagement state · CPC title

• B60W2510/0208

  Clutch engagement state, e.g. engaged or disengaged · CPC title