Title:
FLOW RATE CONTROL METHOD
Document Type and Number:
Japanese Patent JP3523997
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To always accurately control flow rte without needing manual adjustment operation by correcting periodic target flow rate value for every correction unit period based on an error between measured total flow rate value as total quantity that actually flowed in the past control unit period and total flow rate plan value.
SOLUTION: The target correction deviation Esv is calculated from the error between measured total flow rate TPVc and total flow rare plan value TSVn (St1). Whether or not to correct cyclic target flow rte value SVn with the deviation Esv is judged and when correction is performed (St2), the deviation Esv is added to the value SVn to correct periodic target flow rate value SVc (St3). Deviation E between the current flow rate value PV that is acquired by real measurement and corrected cyclic target flow rate value SVn is calculated (St4). The necessary opening degree of a valve in a sampling period in the next period is calculated by PID control with the calculated deviation E as a control index (St5) and the opening degree of the valve is operated as a flow rate control output (St6).
Inventors:
Nagao, Tetsuya
Application Number:
JP118498A
Publication Date:
April 26, 2004
Filing Date:
January 07, 1998
Export Citation:
Assignee:
KUBOTA CORP
International Classes:
F16K31/06; G05B11/36; G05B21/02; G05D7/06; (IPC1-7): G05D7/06; G05B11/36
Attorney, Agent or Firm:
森本 義弘