Patent ID: 6293267
Filing Date: 2001-09-25
Classification: F02D,F02M,Y02T

Abstract:
A control methodology for positioning a control valve in a vehicle engine to achieve a commanded mass flow rate of a compressible medium through the valve, comprising the steps of:collecting valve characterizing data by measuring standard flow rates through the valve for various combinations of valve position and pressure ratio across the valve, subject to standard pressure and temperature conditions of the medium upstream of the valve;converting the collected valve characterizing data to form a table of standard flow rate in terms of valve position and pressure ratio across the valve;during operation of the engine, determining a pressure ratio across the valve, and pressure and temperature conditions of the medium upstream of the valve;addressing the table based on the determined pressure ratio, the commanded flow rate, and the determined pressure and temperature conditions to obtain a position command for the valve; andcontrolling the position of the valve based on the position command.