Patent ID: 7603186
Filing Date: 2009-10-13
Classification: G05B,G05D,Y10T

Abstract:
1. A method for adapting a response time of a mass flow controller while the mass flow controller is controlling flow of a fluid to a reaction vessel, comprising: receiving a set point indicator, the set point indicator indicating a desired flow rate of the fluid; receiving a sensor indicator generated by a sensor, the sensor indicator indicating a flow rate of the fluid being delivered to the vessel; biasing the response time of a closed loop control algorithm to a slow mode; briefly modifying the closed-loop-control algorithm to a fast mode when at least one threshold condition is satisfied based on the at least one of the sensor indicator or the set point indicator, the closed-loop-control algorithm affecting the rate which a valve in the mass flow controller changes position to provide the desired flow rate; gradually modifying the closed-loop-control algorithm back to the slow mode; stabilizing the closed-loop-control algorithm in response to the modifying the response time of the closed-loop-control algorithm by adjusting at least one parameter associated with the closed-loop-control algorithm.