Apparatus and method for controlling operating point of hybrid electric vehicle

• US 9,827,988 B2
• Filed: 09/13/2015
• Issued: 11/28/2017
• Est. Priority Date: 03/02/2015
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Kim, Do Hee, Kim, Tae Soo
• Primary Examiner(s): Khatib, Rami
• Assistant Examiner(s): Wiltey, Nicholas K
• Application Number:
  US14/852,570
• Publication Number:
  US 20160257298A1
• Time in Patent Office: 807 Days
• Field of Search: None
• 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• 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 2050/0051 combined with averaging
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2710/081 Speed
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 30/188 Controlling power parameters of the driveline, e.g. determining the required power
• CPC Class Codes: B60W 30/1882 characterised by the working point of the engine, e.g. by using engine output chart
• CPC Class Codes: B60W 50/10 Interpretation of driver requests or demands
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/84 Data processing systems or methods, management, administration
• CPC Class Codes: Y10S 903/902 Prime movers comprising electrical and internal combustion motors

Abstract

An apparatus and a method for controlling an engine operating point of a hybrid electric vehicle are provided to determine charging and discharging tendency based on a moving average of an engine torque and a demand torque as well as a dynamical event capture. The method includes detecting a demand torque of a driver and determining a charging and discharging tendency by calculating a moving average based on the demand torque. System efficiency is then reflected using a dynamical event capture and the charging and discharging tendency is leveled. A compensation amount of the operating point is also determined based on the leveling of the charging and discharging tendency and the operating point of the hybrid electric vehicle is adjusted based on the compensation amount of the operating point.

Claims

1. A method for controlling an engine operating point of a hybrid electric vehicle, comprising:

detecting, by a controller, a demand torque of a driver;

determining, by the controller, a charging and discharging tendency by calculating a moving average based on the demand torque;

reflecting, by the controller, system efficiency using a dynamical event capture and leveling the charging and discharging tendency;

determining, by the controller, a final compensation amount of the engine operating point based on the leveling of the charging and discharging tendency; and

adjusting, by the controller, the engine operating point of the hybrid electric vehicle based on the final compensation amount of the engine operating point,

wherein the moving average is calculated by determining a charging and discharging tendency torque based on a difference between an engine reference torque and the demand torque.

2. The method of claim 1, wherein the determination of a final compensation amount of the engine operating point based on the leveling of the charging and discharging tendency comprises:

determining, by the controller, a basic compensation amount of the engine operating point;

determining, by the controller, an entry point of compensation;

determining, by the controller, a compensation scaling factor based on the leveling of the charging and discharging tendency; and

determining, by the controller, the final compensation amount of the engine operating point based on the basic compensation amount of the engine operating point and the compensation scaling factor.

3. The method of claim 1, wherein the dynamical event capture is performed by capturing a flow of the demand torque on coordinates including an engine torque and an engine speed.

4. The method of claim 3, wherein the dynamical event capture includes:

subdividing, by the controller, the coordinates of the engine torque and the engine speed into a box and

determining, by the controller, the charging and discharging tendency based on a number of times the flow of the demand torque passes through a boundary of the box.

5. An apparatus for controlling an engine operating point of a hybrid electric vehicle, comprising:

a memory configured to store program instructions; and

a processor configured to execute the program instructions, the program instructions when executed configured to;

detect a running state of the hybrid electric vehicle and a demand torque of a driver;

calculate a moving average based on a received signal of the running state and demand torque and determine a charging and discharging tendency using a dynamical event capture; and

determine a final compensation amount of the engine operating point based on the charging and discharging tendency,

wherein the program instructions when executed are further configured to calculate the moving average by determining a charging and discharging tendency torque based on a difference between an engine reference torque and the demand torque.

6. The apparatus of claim 5, wherein the apparatus further includes:

an accelerator pedal position sensor configured to detect a position value of an accelerator pedal;

a vehicle speed sensor configured to detect a vehicle speed;

an engine speed sensor configured to detect an engine speed; and

a motor speed sensor configured to detect a motor speed.

7. The apparatus of claim 5, wherein the dynamical event capture is performed by capturing a flow of the demand torque on coordinates of an engine torque and an engine speed.

8. The apparatus of claim 7, wherein the dynamical event capture is performed by subdividing the coordinates of the engine torque and the engine speed into a box and determining charging and discharging tendency based on a number of times the flow of the demand torque passes through a boundary of the box.

9. The apparatus of claim 5, wherein the program instructions when executed are further configured to:

reflect system efficiency using the dynamical event capture and level the charging and discharging tendency.

10. The apparatus of claim 5, wherein the program instructions when executed are further configured to:

determine a basic compensation amount of the engine operating point, a basic compensation amount of the engine operating point, a compensation scaling factor, and the final compensation amount of the engine operating point.

11. A non-transitory computer readable medium containing program instructions executed by a controller, the computer readable medium comprising:

program instructions that detect a running state of the hybrid electric vehicle and a demand torque of a driver;

program instructions that calculate a moving average based on a received signal of the running state and demand torque and determine a charging and discharging tendency using a dynamical event capture;

program instructions that determine a final compensation amount of an engine operating point based on the charging and discharging tendency; and

program instructions that calculate the moving average by determining a charging and discharging tendency torque based on a difference between an engine reference torque and the demand torque.

12. The non-transitory computer readable medium of claim 11, further comprising:

program instructions that detect a position value of an accelerator pedal using an accelerator pedal position sensor;

program instructions that detect a vehicle speed using a vehicle speed sensor;

program instructions that detect an engine speed using an engine speed sensor; and

program instructions that detect a motor speed using a motor speed sensor.

13. The non-transitory computer readable medium of claim 11, wherein the dynamical event capture is performed by capturing a flow of the demand torque on coordinates of an engine torque and an engine speed.

14. The non-transitory computer readable medium of claim 13, wherein the dynamical event capture is performed by subdividing the coordinates of the engine torque and the engine speed into a box and determining charging and discharging tendency based on a number of times the flow of the demand torque passes through a boundary of the box.

15. The non-transitory computer readable medium of claim 11, further comprising:

program instructions that reflect system efficiency using the dynamical event capture and level the charging and discharging tendency.

16. The non-transitory computer readable medium of claim 11, further comprising:

program instructions that determine a basic compensation amount of the engine operating point, a basic compensation amount of the engine operating point, a compensation scaling factor, and the final compensation amount of the engine operating point.