Method of controlling drive request torque in hybrid electric vehicle

• US 8,340,882 B2
• Filed: 05/12/2008
• Issued: 12/25/2012
• Est. Priority Date: 12/13/2007
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Kim, Jeong Eun
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): Nguyen, Bao Long T
• Application Number:
  US12/152,159
• Publication Number:
  US 20090157243A1
• Time in Patent Office: 1,688 Days
• Field of Search: None
• US Class Current: 701/90
• CPC Class Codes: B60L 2240/486 Operating parameters
• 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 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2710/1022 Input torque
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers

Abstract

The present invention provides a method of controlling a driver request torque in a hybrid electric vehicle, in which a driver request torque is calculated by determining that a driver has an intention to accelerate, if an accelerator opening degree detected by an accelerator pedal position sensor (APS) is greater than 0% when the accelerator pedal is depressed by the driver who intends to re-accelerate after coasting or decelerating, and a torque discontinuity, which may be caused when the APS is turned on→off→on according to the depression operation of the accelerator pedal by the driver, is controlled using an up/down torque rate limit logic, thus preventing deterioration of driving performance.

For this purpose, the present invention provides a method of controlling a driver request torque in a hybrid electric vehicle, the method including: monitoring a vehicle speed; calculating a maximum torque with respect to the vehicle speed; monitoring an APS; and calculating a driver request torque by determining that a driver has an intention to accelerate and recognizing a minimum request torque as 0 Nm, if an opening degree of the APS is greater than 0%.

Claims

1. A method of controlling a driver request torque in a hybrid electric vehicle, the method comprising:

monitoring, by a processor, a vehicle speed

calculating, by the processor, a maximum

monitoring, by the processor, an accelerator

calculating, by the processor, a driver request torque by determining that a driver has an intention to accelerate and recognizing a minimum request torque of at least 0 Nm, when the calculated request torque is less than 0 nm and the APS is greater than 0%,

wherein an up/down torque rate limit logic is performed to limit a discontinuous change in torque caused when the APS is turned on→

off→

on according to the driver'"'"'s accelerator pedal operation.

2. The method of claim 1, wherein, if the opening degree of the APS is 0%, a minimum torque with respect to a vehicle speed is determined as a creep torque.

3. The method of claim 1, wherein a range of up/down torque rate limit values by the up/down torque rate limit logic is set to an appropriate level in consideration of acceleration performance and driving performance.