Patent ID: 7369920
Filing Date: 2008-05-06
Classification: G05D,Y10T

Abstract:
1. A pressure control system for controlling pressure of a fluid in a chamber, comprising: a pressure sensor configured to measure the pressure of the fluid in the chamber; a valve configured to regulate flow of the fluid from the chamber by moving between an open position and a closed position; and a computer processor configured to generate a pump speed curve of the valve, wherein the pump speed curve shows the pump speed C of the system as controlled by the valve and as a function of position ⊖ of the valve, the computer processor further configured to monitor and modify the pump speed curve so as to maintain a slope of the pump speed curve to at least a minimum value, the computer processor further configured to use the modified pump speed curve to adjust the position of the valve in response to pressure measurements by the pressure sensor, so as to maintain the pressure in the chamber at a desired pressure setpoint, the computer processor further configured to estimate a volume of the chamber, and to generate the pump speed curve using the estimated volume together with pressure measurements made by the pressure sensor at a plurality of positions of the valve.