CLUTCH ENGAGEMENT CONTROL APPARATUS AND METHOD FOR HYBRID VEHICLE

• US 20070276557A1
• Filed: 05/23/2007
• Published: 11/29/2007
• Est. Priority Date: 05/26/2006
• Status: Abandoned Application

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Ashizawa, Hiroyuki, Adachi, Kazutaka, Motosugi, Jun
• Application Number:
  US11/752,550
• Publication Number:
  US 20070276557A1
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/486 Operating parameters
• 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 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• 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 2050/0006 Digital architecture hierarchy
• CPC Class Codes: B60W 2050/0012 Feedforward or open loop systems
• CPC Class Codes: B60W 2510/0241 Clutch slip, i.e. difference between input and output speeds
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2530/16 Driving resistance
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2710/023 Clutch engagement rate
• CPC Class Codes: B60W 2710/0666 : Engine torque
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 2710/105 : Output torque
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility

Abstract

An apparatus and method for controlling operation of a clutch in a hybrid vehicle. A basic transmission torque capacity target value is calculated based on a vehicle driving operation and a vehicle running condition. A target value for the output side rpm of a clutch is calculated from the basic clutch transmission torque capacity target value. A final transmission torque capacity target value of the clutch, which makes smaller a clutch output side rpm difference Noerr between the clutch output side rpm target value and a clutch output side rpm detection value detected by an rpm detecting device, is calculated, and engagement of the clutch is controlled so that the transmission torque capacity of the clutch becomes equal to the final clutch transmission torque capacity target value.

Claims

1. A clutch engagement control apparatus for a hybrid vehicle, comprising:

a plurality of different kinds of power sources;

a clutch interposed between the power sources and driving wheels, the clutch capable of varying a transmission torque capacity and having an input side and an output side;

a clutch output side rpm detecting device that detects an rpm detection value of the output side of clutch; and

a controller configured to;

calculate a basic transmission torque capacity target value of the clutch based on a vehicle driving operation by a driver and a vehicle running condition;

calculate a target rpm value for the output side of the clutch based on the basic clutch transmission torque capacity target value;

calculate a final transmission torque capacity target value for the clutch that decreases a difference between the target rpm value and the rpm detection value; and

control engagement of the clutch so that the transmission torque capacity of the clutch becomes equal to the final transmission torque capacity target value.

2. The apparatus according to claim 1 wherein the controller is further configured to:

calculate a transmission torque capacity correction value that decreases the difference between the target rpm value and the rpm detection value; and

calculate the final transmission torque capacity target value by correcting the basic clutch transmission torque capacity target value with the transmission torque capacity correction value.

3. The apparatus according to claim 2 wherein the controller is further configured to calculate the transmission torque capacity correction value Tc1fb according to an equation Tc1fb=Kc1p+(Kc1i/s)}·

Noerr wherein Kc1p is a proportional control gain, Kc1i is an integration control gain, and Noerr is the difference between the target rpm value and the rpm detection value.

4. The apparatus according to claim 1 wherein the controller is further configured to:

calculate an output shaft driving torque target value tTo according to an equation tTo=tTc1base−

Tr wherein tTc1base is the basic clutch transmission torque capacity target value and Tr is a vehicle running resistance at a level road; and

calculate the target rpm value tNo according to an equation tNo/tTo={(Gm·

Gf)²/Jo}×

1/s) wherein Jo is a moment of inertia of the vehicle, Gm is a gear ratio of a transmission in a drive train of the vehicle and Gf is a final reduction ratio of a final reduction gear unit in the drive train.

5. The apparatus according to claim 1 wherein the controller is further configured to:

calculate an output shaft driving torque target value tTo according to an equation tTo=tTc1base−

Tr−

(Tslope×

Kslope) wherein tTc1base is the basic clutch transmission torque capacity target value, Tr is a vehicle running resistance at a level road, Tslope is a slope portion vehicle running resistance due to a road surface slope, and Kslope is a slope portion running resistance coefficient between 0 and 1.0; and

calculate the target rpm value tNo according to an equation tNo/tTo={(Gm·

Gf)²/Jo}×

1/s) wherein Jo is a moment of inertia of the vehicle, Gm is a gear ratio of a transmission in a drive train of the vehicle and Gf is a final reduction ratio of a final reduction gear unit in the drive train.

6. The apparatus according to claim 1, further comprising:

a clutch input side rpm detecting device that detects a clutch input side rpm detection value of the input side of the clutch; and

wherein the controller is further configured to;

calculate a clutch output side rpm upper limit value by subtracting a predetermined value from the clutch input side rpm detection value; and

restrict the target rpm value by the clutch output side rpm upper limit value.

7. The apparatus according to claim 1 wherein the plurality of different kinds of power sources comprise:

an engine; and

a motor disposed between the engine and the input side of the clutch, the apparatus further comprising;

a second clutch disposed between the engine and the motor.

8. A clutch engagement control apparatus for a hybrid vehicle including a power train having at least two power sources and a clutch between the at least two power sources and a driving wheel, the apparatus comprising:

means for calculating a basic transmission torque capacity target value of the clutch based on a vehicle driving operation by a driver and a vehicle running condition;

means for calculating a target rpm value for the output side of the clutch based on the basic clutch transmission torque capacity target value;

means for calculating a final transmission torque capacity target value for the clutch that decreases a difference between the target rpm value and a detected rpm value on the output side of the clutch; and

means for controlling engagement of the clutch so that the transmission torque capacity of the clutch becomes equal to the final transmission torque capacity target value.

9. The apparatus according to claim 8, further comprising:

means for detecting the detected rpm value on the output side of the clutch.

10. A clutch engagement control method for a hybrid vehicle including a power train having at least two power sources and a clutch between the at least two power sources and a driving wheel, the method comprising:

calculating a basic transmission torque capacity target value of the clutch based on a vehicle driving operation by a driver and a vehicle running condition;

calculating a target rpm value for an output side of the clutch based on the basic clutch transmission torque capacity target value;

calculating a final transmission torque capacity target value for the clutch that decreases a difference between the target rpm value and a detected rpm value on the output side of the clutch; and

controlling engagement of the clutch so that the transmission torque capacity of the clutch becomes equal to the final transmission torque capacity target value.

11. The method according to claim 10, further comprising:

calculating a transmission torque capacity correction value that decreases the difference between the target rpm value and the detected rpm value; and

wherein calculate the final transmission torque capacity target value further comprises;

correcting the basic clutch transmission torque capacity target value with the transmission torque capacity correction value to obtain the final transmission torque capacity target value.

12. The method according to claim 11 calculating the transmission torque capacity correction value further comprises:

calculating the transmission torque capacity correction value Tc1fb according to an equation Tc1fb={Kc1p+(Kc1i/s)}·

Noerr wherein Kc1p is a proportional control gain, Kc1i is an integration control gain, and Noerr is the difference between the target rpm value and the detected rpm value.

13. The method according to claim 11, further comprising:

detecting a clutch input side rpm detection value of an input side of the clutch;

calculating a clutch output side rpm upper limit value by subtracting a predetermined value from the clutch input side rpm detection value; and

restricting the target rpm value by the clutch output side rpm upper limit value.

14. The method according to claim 10, further comprising:

calculating an output shaft driving torque target value tTo according to an equation tTo=tTc1base−

Tr wherein tTc1base is the basic clutch transmission torque capacity target value and Tr is a vehicle running resistance at a level road; and

wherein calculating the target rpm value further comprises;

calculating the target rpm value tNo according to an equation tNo/tTo=((Gm·

Gf)2/Jo}×

1/s) wherein Jo is a moment of inertia of the vehicle, Gm is a gear ratio of a transmission in a drive train of the vehicle and Gf is a final reduction ratio of a final reduction gear unit in the drive train.

15. The method according to claim 10, further comprising:

calculating an output shaft driving torque target value tTo according to an equation tTo=tTc1base−

Tr−

(Tslope×

Kslope) wherein tTc1base is the basic clutch transmission torque capacity target value, Tr is a vehicle running resistance at a level road, Tslope is a slope portion vehicle running resistance due to a road surface slope, and Kslope is a slope portion running resistance coefficient between 0 and 1.0; and

wherein calculating the target rpm value further comprises;

calculating the target rpm value tNo according to an equation tNo/tTo={(Gm·

Gf)2/Jo}×

1/s) wherein Jo is a moment of inertia of the vehicle, Gm is a gear ratio of a transmission in a drive train of the vehicle and Gf is a final reduction ratio of a final reduction gear unit in the drive train.

16. The method according to claim 10, further comprising:

detecting the detected rpm value on the output side of the clutch.

17. The method according to claim 10, further comprising:

detecting a clutch input side rpm detection value of an input side of the clutch;

calculating a clutch output side rpm upper limit value by subtracting a predetermined value from the clutch input side rpm detection value; and

restricting the target rpm value by the clutch output side rpm upper limit value.

18. The method according to claim 10 wherein calculating the basic transmission torque capacity target value of the clutch based on the vehicle driving operation by the driver and the vehicle running condition further comprises:

determining a vehicle driving torque target value using an accelerator opening degree and a vehicle speed, the vehicle driving torque target value being the basic transmission torque capacity target value.

19. The method according to claim 10, further comprising:

obtaining a transmission torque capacity coefficient Cc1 of the clutch using a speed ratio of the detected rpm value to a clutch input side rpm detection value Ni of an input side of the clutch and a predetermined relationship between transmission torque capacity coefficients and speed ratios; and

wherein calculating the basic transmission torque capacity target value of the further comprises;

calculating the basic transmission torque capacity target value tTc1base according to an equation tTc1base=Cc1×

Ni².