METHOD AND CONTROL DEVICE WHICH CAN COPE WITH PROCESS CHARACTERISTIC CHANGE

摘要

PROBLEM TO BE SOLVED: To provide a technique for solving the problems of increased frequency of blade replacement, increased cost, reduced operation rate and increased operator load in coating machine control in which an inverse range having an inverse relationship between a coating amount and a control signal shifts with time to make it necessary to narrow down a control range of blade position apart from the inverse range, and when the inverse range overlaps the control range, an operator must manually control it.;SOLUTION: It is determined whether an inverse range is reached on the basis of current and past process quantity measurements and control signals, and if the inverse range is reached, an inverse gain different from a gain used for a normal range is set and a control signal is computed from the set gain and the difference of the measurement from a process quantity set point. A process characteristic is further estimated, and if it is about the boundary, the control signal is temporarily increased to shift it away from the boundary. When the characteristic changes, the control signal is changed to compensate for the change.;COPYRIGHT: (C)2011,JPO&INPIT