FLUID CONTROL DEVICE, CONTROL PROGRAM AND FLUID CONTROL SYSTEM

• Main Authors: KUNIDA DAICHI, TAKIJIRI KOTARO, IEKI ATSUSHI
• Format: Patent
• Language: English; Japanese
• Published: 29.08.2019
• Subjects: CONTROL OR REGULATING SYSTEMS IN GENERAL; CONTROLLING; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS ORELEMENTS; PHYSICS; REGULATING; SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES

To provide a fluid control device that is less likely to cause control failure even in the event of an abnormal state in which a condition in which an opening/closing valve is closed continues while feedback control continues in a fluid control system.SOLUTION: A fluid control device comprises: a fluid sensor that measures a fluid flowing in a channel; a fluid control valve that controls the fluid; and a fluid control unit that executes feedback control for the fluid control valve such that a measurement value measured by the fluid sensor reaches a predetermined target value. The fluid control unit comprises: a determination unit that determines whether an abnormal state, in which the measurement value measured by the fluid sensor is equal to or smaller than an insufficient fluid threshold and an opening degree of the fluid control value is equal to or larger than a limit value, has arisen or not; and a gain alteration unit that, in a case where the determination unit determines that the abnormal state has arisen, alters a gain value used for the feedback control to a value smaller than a gain value used for the feedback control executed when the abnormal state is not arising.SELECTED DRAWING: Figure 2 【課題】流体制御システムにおいてフィードバック制御が継続しながら開閉弁が閉じられた状態が継続する異常状態になった場合においても、制御不良が生じ難い流体制御装置を提供する。【解決手段】流路を流れる流体を測定する流体センサと、前記流体を制御する流体制御弁と、前記流体センサで測定される測定値が予め定められた目標値に近づくように前記流体制御弁をフィードバック制御する流体制御部とを具備し、前記流体制御部が、前記流体センサで測定された測定値が前記目標値よりも小さい値である過少流量閾値以下であり、かつ、前記流体制御弁の弁開度が限界値以上になっている状態を継続する異常状態になったか否かを判定する判定部と、前記判定部によって前記異常状態になったと判定された場合に、前記フィードバック制御に用いられるゲイン値を、前記異常状態でない場合に前記フィードバック制御に用いられるゲイン値よりも小さな値に変更するゲイン変更部とを備える。【選択図】図２