Patent ID: 6349236
Filing Date: 2002-02-19
Classification: G05B

Abstract:
In a multivariate control system havingan ordered plurality of controlled variables, each of said controlled variables having a measured value a predefined value defining its position within the order, and an associated setpoint having an original setpoint value, each of said controlled variables being selected from active controlled variables and inactive controlled variables, and a plurality of manipulated variables, each of said manipulated variables being selected from available manipulated variables and unavailable manipulated variables, a method for changing the difference between the number of active controlled variables and the number of available manipulated variables, said method comprising: classifying each of said controlled variables as belonging to one of an ordered plurality of classes, each of said classes having a rank defining its position within the order, and, changing the number of said active controlled variables, said changing further including at least one of, relinquishing control over a lowest priority controlled variable, said lowest priority controlled variable being that active controlled variable which is in the class having the lowest rank and which has the lowest priority of all controlled variables in that class, and asserting control over a highest priority controlled variable, said highest priority controlled variable being that inactive controlled variable which is in the class having the highest rank and which has the highest priority of all controlled variables in that class.