PURPOSE: To make optimum adjustments of target value follow-up characteristics and disturbance suppression characteristics by multiplying the output of a dynamic characteristic transfer function means, separated from a controlled variable filter, by a necessary differential quantity optimization coefficient and applying the result to the output of PI adjustment arithmetic.

CONSTITUTION: A target value R (s) and the controlled variable Y01 (S) for adjustment obtained by passing the feedback controlled variable PS (s) of a controlled system through the controlled variable filter 2 are led to a deviation arithmetic means 3 to obtain a deviation E (s). Then PI adjustment arithmetic for eliminating the deviation E (s) is performed by a PI adjusting means 4 and the obtained operation output and disturbance D (s) are added and applied to the controlled system 1. At this time, the controlled variable filter 2 is separated into the dynamic characteristic transfer function means 14 and a static transfer function means 14 and the signal obtained by multiplying the target value by a coefficient (r) is applied to the dynamic transfer function means 14 from the signal obtained by multiplying the controlled variable by a coefficient δ without directly applying the controlled variable. Consequently, differentiating operation can be optimized with a coefficient by combining the PI adjusting means 4 and controlled variable filter 2 together.