Abstract: A control system frequency response curve forming device for forming an comprising an original frequency response curve of an object to be controlled according to the dynamic characteristic data of the object; a model selector for selecting one of transfer function models which are low degree transfer functions prepared in advance to the original frequency response curve of the objects; an approximate curve moving device for moving an approximate curve corresponding to the selected model transfer function toward and away in order to fit the original frequency response curve and fixing a position of the approximate curve; a parameter deciding device for deciding parameters of the selected model transfer function according to the fixed position of the approximate curve; a selector for selecting one of control parameters deciding algorithms; and a control parameters deciding device for deciding the control parameters based on the selected model transfer function and according to the selected control deciding alg

Abstract: An adaptive process control system comprises a controller of an I-P type generating a manipulating variable signal with a feed forward circuit responsive to the set-point signal r(t), an integrator responsive to a difference between a process variable signal y(t) and set-point signal r(t), and a feedback circuit responsive to the process variable signal y(t). An identification signal generator superposes a persistantly exciting identification signal h(t) to the control system. A frequency characteristic identifying circuit receives a discrete controlled data u(k) and y(k), estimates the parameters of the ARMA model by the least square method to identify the pulse transfer function, and obtains the transfer function in the continuous system as the frequency characteristics of gain and phase. A controller parameter calculating circuit calculates the controller parameters of the controller, such as integration gain K, proportional gain f.sub.o, and feed forward gain f.sub.