Plant control system

A plant control system for controlling a plant, comprising:

• an actuator for generating an input to the plant;
• first detecting means for detecting an output from the plant;
• manipulated variable determining means for sequentially generating a manipulated variable which manipulates the input to the plant to converge the output from said first detecting means to a predetermined target value;
• actuator control means for controlling operation of said actuator based on said manipulated variable to manipulate the input to the plant;
• estimating means for sequentially generating data representing an estimated value of the output from said first detecting means after a total dead time which is the sum of a first dead time of said plant and a second dead time of an input manipulating system, according to a predetermined algorithm constructed based on a model of a behavior of the plant as a system for generating the difference between the output from said first detecting means and said target value with a response delay and the first dead time from the difference between the input to the plant and a predetermined reference value, and a model of a behavior of the input manipulating system as a system comprising said actuator control means and said actuator for generating the input to said plant with said second dead time from said manipulated variable, said manipulated variable determining means comprising means for generating said manipulated variable using the data generated by said estimating means;
• and
• reference value variably setting means for variably setting said predetermined reference value depending on the manipulated variable generated by said manipulated variable determining means.