Vehicle equipped with electric motor and stability control method therefor

Patent metadata

Field	Value
Publication number	US-12122247-B2
Application number	US-202117459574-A
Country	US
Kind code	B2
Filing date	Aug 27, 2021
Priority date	Sep 23, 2020
Publication date	Oct 22, 2024
Grant date	Oct 22, 2024

Abstract

A method of controlling stability of a motorized vehicle having an electric motor as a drive source includes determining a slope of a road ahead, when sensing a sudden slope change point as a result of determination, determining a correction section based on the sudden slope change point, and correcting stability control torque in the correction section to compensate for motion of the vehicle body due to a change in the slope of the road using a pitching motion of the vehicle body caused by the torque of the electric motor.

First claim

What is claimed is:

1. A method of controlling stability of a motorized vehicle having an electric motor as a drive source, the method comprising:
determining a slope of a road ahead;
determining a sudden slope change point comprising a point where a sign of the slope changes or a point where the slope changes by a predetermined amount as a result of the determination of the slope of the road;
determining a correction section along the road based on the sudden slope change point, the correction section comprising a section before the sudden slope change point on the road; and
correcting a stability control torque in the correction section to compensate for motion of a vehicle body due to a change in the slope of the road using a pitching motion of the vehicle body caused by a torque of the electric motor,
wherein determining the correction section comprises:
determining the sudden slope change point based on slope information of a navigation system;
setting a reference point ahead of the sudden slope change point based on a resolution of the slope information; and
setting the correction section based on the reference point.

2. The method according to claim 1 , wherein setting the reference point comprises:
setting the reference point ahead of the sudden slope change point at a distance corresponding to the resolution.

3. The method according to claim 1 , wherein determining the correction section further comprises:
correcting the reference point based on at least one of acceleration sensor information, information on whether a preceding vehicle is sensed, or information on whether a lane disappears.

4. The method according to claim 3 , wherein setting the correction section based on the reference point comprises:
when the reference point is corrected, setting the correction section based on the corrected reference point.

5. The method according to claim 1 , wherein, when a slope at the sudden slope change point changes from an uphill slope to a downhill slope, correcting the stability control torque comprises:
lowering an upper limit of the stability control torque; or
applying a negative linear torque offset to the stability control torque.

6. The method according to claim 1 , wherein, when a slope at the sudden slope change point changes from an uphill slope to a downhill slope, correcting the stability control torque comprises:
increasing a coasting torque; or
enhancing an up-rate limit of torque increment according to operation of an accelerator pedal.

7. The method according to claim 1 , wherein, when a slope at the sudden slope change point changes from a downhill slope to an uphill slope, correcting the stability control torque comprises:
increasing a lower limit of the stability control torque; or
applying a positive linear torque offset to the stability control torque.

8. The method according to claim 1 , wherein, when a slope at the sudden slope change point changes from a downhill slope to an uphill slope, correcting the stability control torque comprises:
decreasing a coasting torque; or
enhancing a down-rate limit of torque decrement according to operation of an accelerator pedal.

9. A non-transitory computer-readable recoding medium having a program recorded thereon, the program to direct a processor to perform acts of:
determining a slope of a road ahead;
determining a sudden slope change point comprising a point where a sign of the slope changes or a point where the slope changes by a predetermined amount as a result of the determination of the slope of the road;
determining a correction section along the road based on the sudden slope change point, the correction section comprising a section before the sudden slop change point on the road; and
correcting a stability control torque in the correction section to compensate for motion of a vehicle body due to a change in the slope of the road using a pitching motion of the vehicle body caused by a torque of an electric motor,
wherein determining the correction section comprises:
determining the sudden slope change point based on slope information of a navigation system;
setting a reference point ahead of the sudden slope change point based on a resolution of the slope information; and
setting the correction section based on the reference point.

10. A motorized vehicle comprising:
an electric motor;
a first controller configured to control the electric motor; and
a second controller configured to:
determine a slope of a road ahead;
determine a sudden slope change point comprising a point where a sign of the slope changes or a point where the slope changes by a predetermined amount as a result of the determination of the slope of the road;
determine a correction section along the road based on the sudden slope change point, the correction section comprising a section before the sudden slope change point on the road;
correct a stability control torque in the correction section to compensate for motion of a vehicle body due to a change in the slope of the road using a pitching motion of the vehicle body caused by a torque of the electric motor; and
transmit, to the first controller, a torque command to which the corrected stability control torque is applied,
wherein the second controller is configured to:
determine the sudden slope change point based on slope information of a navigation system;
set a reference point ahead of the sudden slope change point based on a resolution of the slope information; and
set the correction section based on the reference point.

11. The motorized vehicle according to claim 10 , wherein the second controller is configured to:
set the reference point ahead of the sudden slope change point at a distance corresponding to the resolution.

12. The motorized vehicle according to claim 10 , wherein the second controller is configured to:
correct the reference point based on at least one of acceleration sensor information, information on whether a preceding vehicle is sensed, or information on whether a lane vanishes.

13. The motorized vehicle according to claim 12 , wherein, when the reference point is corrected, the second controller is configured to:
set the correction section based on the corrected reference point.

14. The motorized vehicle according to claim 10 , wherein, when a slope at the sudden slope change point changes from an uphill slope to a downhill slope, the second controller is configured to:
lower an upper limit of the stability control torque; or
apply a negative linear torque offset to the stability control torque.

15. The motorized vehicle according to claim 10 , wherein, when a slope at the sudden slope change point changes from an uphill slope to a downhill slope, the second controller is configured to:
increase a coasting torque; or
enhance an up-rate limit of torque increment according to operation of an accelerator pedal.

16. The motorized vehicle according to claim 10 , wherein, when a slope at the sudden slope change point changes from a downhill slope to an uphill slope, the second controller is configured to:
increase a lower limit of the stability control torque; or
apply a positive linear torque offset to the stability control torque.

17. The motorized vehicle according to claim 10 , wherein, when a slope at the sudden slope change point changes from a downhill slope to an uphill slope, the second controller is configured to:
decrease a coasting torque; or
enhance a down-rate limit of torque decrement according to operation of an accelerator pedal.

Assignees

• Hyundai Motor Co Ltd
• Kia Corp

Inventors

• Son Hui Un
• Lee Jea Mun
• Park Jae Young
• Kim Young Eun
• Kim Sang Joon
• Yu Sung Hoon

Classifications

• B60L2250/26

  by pedal actuation · CPC title

• B60Y2300/02

  Control of vehicle driving stability · CPC title

• B60Y2300/18066

  Coasting · CPC title

• B60Y2200/92

  Hybrid vehicles · CPC title

• B60Y2200/91

  Electric vehicles · CPC title