SELF-TUNING CONTROLLER

PURPOSE:To execute self-tuning without receiving directly the influence caused by a fluctuation of a manipulated variable. CONSTITUTION:The controller is provided with a control operating part 12, a closed loop transfer function identifying part 20 for identifying a closed loop transfer function of the whole control system, based on a target value and a controlled variable, an object transfer function identifying part 22 for identifying a transfer function of a control object 30 by using a coefficient of the identified closed loop transfer function and a control parameter of the control operating part 12, a reference model setting part 18 for setting a reference model for showing a desirable control performance of the whole control system, and a parameter calculating part 16 for determining a new control parameter of the control operating part 12 for realizing the control system being equivalent to the reference model.