Control of multi variable processes

摘要

A system for controlling multi variable processes 4 comprises a means for defining a feasible region for the process variables, means to define, for each process variable, a range due to the values of the other process variables, means for detecting whether an alarm condition exists, means responding to the existence of an alarm condition, means to calculate a change required to rectify the alarm condition and means for displaying or implementing the change. The defined feasible region for the process variables is based on sets of values accumulated in relation to multiple operations of the process. An alarm condition is said to exist when the current value of a variable lies outside the range defined for it. The feasible region may be defined by convex hulls derived between pairs of the process variables. An iterative process may be used to calculate the change required to rectify an alarm condition.