DEVICE FOR CONTROLLING GAS MIXING, METHOD FOR CONTROLLING GAS MIXING RATIO THEREIN

摘要

PURPOSE: A gas mixing control device and a method for controlling gas mixing ratio therein are provided to prevent the errors of a gas mixing ratios by possessively adjusting the target flow rate of the element gas. CONSTITUTION: A method for gas mixing ratio in a gas mixing control device is as follows. The control device transmits each target flow rate value predetermined by target mixing ratio to multiple flow rate controllers for controlling flow rate in multiple pipes(S330). The control device receives the actual flow rate values of each outlet of the pipes from the flow rate controllers(S340). The control device corrects the target flow rate value for the flow rate controllers for controlling the flow rates in rest pipes except for pipes in which the target flow rate value and the practical flow rate values are escaped from a predetermined error range. The control device receives the corrected target flow rate value to the flow rate controllers for controlling the flow rate of the rest pipes. [Reference numerals] (AA) Start; (BB) Over error range; (CC) Within the error range; (DD) Finish; (S310) Input and save of a target mixing ratio; (S320) Determining a target flow rate value of each flow rate controller according to the target mixing ratio; (S330) Transmitting each target flow rate to each flow rate controller; (S340) Receiving an actual flow rate value of each outlet of multiple pipes; (S350) Discriminating the errors of the target flow rate value and the actual flow rate value; (S360) Determining a modified target flow rate value of the flow rate controllers in rest pipes except pipes diverging from the error range