Flow-based control method for an engine control valve
US6293267A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2000 |
| Grant date | Sep 25, 2001 |
| Priority date | — |
| Expiry date | Mar 23, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An improved control methodology for an engine control valve, in which the valve is positioned in response to a commanded flow rate of the controlled medium. The method involves a valve characterization procedure in which the actual flow rate is measured for various combinations of valve position and pressure ratio across the valve, subject to a standard set of upstream pressure and temperature values. This results in a table of valve position in terms of pressure ratio and standard flow rate--that is, flow rate under the standard upstream pressure and temperature values. In operation, a controller addresses the table to obtain the desired valve position as a function of a determined pressure ratio across the valve, and a desired standard flow rate determined based on the commanded flow rate and the pressure and temperature of the controlled medium upstream of the valve, relative to the standard pressure and temperature values. The required calibration effort is significantly reduced compared to the usual ad-hoc approach, and the control is based on the physical characteristics of the valve so that the commanded flow rate can be scheduled based on engine control considerations. Addi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.