Method and apparatus for controlling operation of hydraulic idle stop and go (ISG) system using electro hydraulic power steering (EHPS) system

• US 10,252,718 B2
• Filed: 09/12/2016
• Issued: 04/09/2019
• Est. Priority Date: 10/15/2015
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Choi, Young-Seol
• Primary Examiner(s): Goldman, Richard A
• Application Number:
  US15/262,122
• Publication Number:
  US 20170106868A1
• Time in Patent Office: 939 Days
• Field of Search: 701 70, 701112, 701113, 701 90, 180442, 180441
• CPC Class Codes: B60W 2510/20 Steering systems
• CPC Class Codes: B60W 2510/30 Auxiliary equipments
• CPC Class Codes: B60W 2556/00 Input parameters relating to data
• CPC Class Codes: B60W 30/18018 Start-stop drive, e.g. in a traffic jam
• CPC Class Codes: B62D 5/065 characterised by specially adapted means for varying pressurised fluid supply based on need, e.g. on-demand, variable assist
• CPC Class Codes: E02F 9/2087 Control of vehicle steering for steering with hydraulic or pneumatic drives E02F9/225
• CPC Class Codes: F02N 11/084 State of vehicle accessories, e.g. air condition or power steering
• CPC Class Codes: F02N 2200/0808 Steering state, e.g. state of power assisted steering
• CPC Class Codes: F02N 7/00 Starting apparatus having fluid-driven auxiliary engines or apparatus
• CPC Class Codes: F15B 1/024 used as a supplementary power source, e.g. to store energy in idle periods to balance pump load
• CPC Class Codes: F15B 1/027 having accumulator charging devices
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method for controlling operation of a hydraulic idle stop and go (ISG) system using an electro hydraulic power steering (EHPS) system includes measuring a pressure in an accumulator, a steering angle, and a steering angular velocity; determining whether the measured pressure in the accumulator is less than an absolute value of a first reference pressure; determining whether the measured steering angle is less than an absolute value of a reference angle when the measured pressure in the accumulator is less than the absolute value of the first reference pressure; determining whether the measured steering angular velocity is less than an absolute value of a reference angular velocity when the measured steering angle is less than the absolute value of the reference angle; and opening a solenoid valve when the measured steering angular velocity is less than the absolute value of the reference angular velocity.

Claims

1. A method for controlling operation of a hydraulic idle stop and go (ISG) system using an electro hydraulic power steering (EHPS) system, comprising:

measuring, by sensors, a pressure in an accumulator, a steering angle, and a steering angular velocity;

determining, by a controller, whether the measured pressure in the accumulator is less than an absolute value of a first reference pressure;

determining, by the controller, whether the measured steering angle is less than an absolute value of a reference angle when the measured pressure in the accumulator is less than the absolute value of the first reference pressure;

determining, by the controller, whether the measured steering angular velocity is less than an absolute value of a reference angular velocity when the measured steering angle is less than the absolute value of the reference angle; and

opening, by the controller, a solenoid valve when the measured steering angular velocity is less than the absolute value of the reference angular velocity.

2. The method of claim 1, further comprising determining whether the measured pressure in the accumulator exceeds an absolute value of a second reference pressure after the opening the solenoid valve.

3. The method of claim 2, further comprising closing the solenoid valve when the measured pressure in the accumulator exceeds the absolute value of the second reference pressure.

4. The method of claim 3, further comprising operating the ISG system after the closing the solenoid valve.

5. The method of claim 4, wherein the step of operating the ISG system is performed when the measured pressure in the accumulator is equal to or greater than the absolute value of the first reference pressure.

6. The method of claim 1, wherein the step of measuring the pressure is executed again when the measured steering angle is equal to or greater than the absolute value of the reference angle.

7. The method of claim 1, wherein the step of measuring the pressure is executed again when the measured steering angular velocity is equal to or greater than the absolute value of the reference angular velocity.

8. The method of claim 1, wherein the reference angle is 540°

.

9. The method of claim 1, wherein the reference angular velocity is 180°

/sec.

10. The method of claim 2, wherein the first reference pressure is equal to the second reference pressure.

11. The method of claim 10, wherein the first reference pressure and the second reference pressure are 10 MPa.