Patent ID: 7921832

Claim:
A control system for a plant, comprising: feedback controlling means for calculating a feedback control input so that a controlled output of said plant coincides with a target value; hold control input calculating means for calculating a hold control input according to a parameter indicative of the controlled output of said plant, the hold control input being a control input for maintaining a control deviation between the controlled output and the target value at a value equal to or less than a predetermined threshold value when the target value is maintained at a constant value; and control input setting means for setting a control input to the feedback control input of said plant, when the control deviation is greater than the predetermined threshold value, and setting the control input to the hold control input, when the control deviation is equal to or less than the predetermined threshold value, wherein the feedback controlling means is further for controlling the feedback control input to gradually approach to or coincide with the hold control input, when the control input is set to the hold control input.