Vehicle system and method for controlling torque delivery during transmission engagements with road grade and mass estimation

• US 10,005,375 B2
• Filed: 01/19/2017
• Issued: 06/26/2018
• Est. Priority Date: 10/02/2014
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Yamazaki, Mark Steven, Yu, Hai, Nefcy, Bernard D., Nedorezov, Felix, Liang, Wei
• Primary Examiner(s): Holmes, Justin
• Assistant Examiner(s): Hannon, Timothy
• Application Number:
  US15/409,650
• Publication Number:
  US 20170129363A1
• Time in Patent Office: 523 Days
• 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: B60L 15/2054 by controlling transmissions or clutches
• CPC Class Codes: B60L 15/2081 for drive off on a slope
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/642 Slope of road
• CPC Class Codes: B60L 2260/44 by parameter estimation
• 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 20/30 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 2050/0012 Feedforward or open loop systems
• CPC Class Codes: B60W 2530/10 Weight
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 30/19 Improvement of gear change, e.g. by synchronisation or smoothing gear shift
• CPC Class Codes: B60W 40/076 Slope angle of the road
• CPC Class Codes: B60W 40/13 Load or weight
• CPC Class Codes: B60Y 2400/79 Drive shafts, output shafts or propeller shafts
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y10S 903/902 : Prime movers comprising electrical and internal combustion motors

Abstract

A method includes controlling a torque output of an electric machine of an electrified vehicle based on estimated loads present during a transmission engagement of the electrified vehicle. Controlling the torque output may include merging a first feed-forward torque with a feedback torque if an input shaft of a transmission gearbox is spinning, or merging a second, different feed-forward torque with the feedback torque if the input shaft is not spinning.

Claims

1. A method, comprising:

adjusting a torque output of an electric machine during a transmission engagement of an electrified vehicle, wherein adjusting the torque output includes merging a first feed-forward torque with a feedback torque if an input shaft of a transmission gearbox is spinning and merging a second, different feed-forward torque with the feedback torque if the input shaft is not spinning.

2. The method as recited in claim 1, comprising estimating torque loads present during the transmission engagement.

3. The method as recited in claim 2, wherein the torque loads are based on at least a road grade estimate, a vehicle mass estimate, driveline loads, and transmission pump loads.

4. The method as recited in claim 2, wherein the torque loads are based on at least an amount of inertia required to spin up the input shaft of the transmission gearbox.

5. The method as recited in claim 1, wherein the torque output is adjusted each time a shift device of the electrified vehicle is moved from a neutral gear to a drive gear.

6. The method as recited in claim 5, wherein movement of the shift device from the neutral gear to the drive gear indicates that the transmission engagement is likely.

7. The method as recited in claim 1, wherein the first feed-forward torque and the second, different feed-forward torque compensate for expected changes in torque loads that are present during the transmission engagement.

8. The method as recited in claim 1, wherein the feedback torque is an adjustment torque that maintains a smooth speed profile of the electric machine as the torque output is adjusted to achieve a target speed of the electric machine.

9. The method as recited in claim 1, wherein the first feed-forward torque is a pre-determined torque based on a plurality of loads present during the transmission engagement when the input shaft is spinning.

10. The method as recited in claim 1, wherein the second, different feed-forward torque is a pre-determined torque based on a plurality of loads present during the transmission engagement when the input shaft is not spinning.

11. The method as recited in claim 1, wherein the first feed-forward torque and the second, different feed-forward torque are derived by summing a plurality of torque compensation values that estimate loads present during the transmission engagement.

12. The method as recited in claim 1, wherein the electrified vehicle is a modular hybrid transmission (MHT) vehicle that includes the transmission gearbox, the electric machine, and a torque converter disposed between the electric machine and the transmission gearbox.