抄録
This paper proposes a new tuning method for PID; I-PD process control system, and describes its control characteristics for various controlled objects.
The procedure of the improved ultimate sensitivity method consists of
(1) measuring the ultimate sensitivity KC, the ultimate period PC, and the dead time L of process.
(2) estimating the characteristic type of process.
(3) finding the multiplier factors fK; fI; fD in the charts-based on the Kitamori's partial model matching method, using the normalized dead time LN (=L/PC) and the characteristic type of process.
(4) calculating the optimal values of the PID; I-PD control parameter from the followings, the proportional gain KP=fK·KCthe integral time TI=fI·PCthe derivative time TD=fD·PC
For controlled objects with the wide range of the ratio of dead time L to lag time constant T, step response curves, which are demonstrated in simulation studies, show the effectiveness of the method, and the importance of the parameter LN in the design of control system.
