METHOD AND CONTROLLER FOR CONTROLLING VESSEL FLUID LEVEL BY OUTFLOW FLOW RATE

摘要

PROBLEM TO BE SOLVED: To provide a vessel fluid level control method which is excellent in control followingness to an outflow flow rate, maintains a vessel fluid level within a desired range and depends on mechanical reliability and an outflow flow rate with high robustness. ;SOLUTION: A flow rate controller 5 is provided with an inflow and outflow flow rate difference correcting means 11 which estimates inflow and outflow flow rate difference (Q2-Q1) to a relay tank 1 from the level fluctuation value Δh of the tank 1, a fluid level improving and correcting means 512 which outputs flow rate correction Qc to a level target value LSV at control time Tc, starts a correcting means 511 when the level control deviation (h) of the relay tank deviates equally to or more than threshold (h1 and -h1) to operate flow rate correction Qd1, controls an inflow flow rate Q2 with a flow rate target value QSV correcting an outflow flow rate Q1 with the correction Qd1 and the correction Qc, restarts the means 511 when the control deviation (h) comes to within threshold (h2 and -h2) to operate flow rate correction quantity Qd2 and controls the inflow flow rate Q2 with the value QSV correcting the flow rate Q1 with correction Qd2.;COPYRIGHT: (C)2000,JPO