PIIF D CONTROLLER FOR LINEAR TIME INVARIANT SINGLE INPUT/SINGLE OUTPUT SYSTEMS
S.M. Radaideh, Mohammed T. Hayajneh, Issam A. Smadi · 2004
The aim of this paper is to auto tune the length of the integration interval, �, of the PIID controller in such a manner as to increase its accuracy using the fuzzy theory which generalizes 0 and 1 membership values of a crisp set to a membership function of a fuzzy sets which are classes with an un-sharp boundary. In other words, the length of integration in the proposed controller is a function of the error signal, and computed using a fuzzy logic controller. The modified controller will be denoted as PIIFD, which is a modification for PIID controller. In order to test the effectiveness of the proposed controller and to compare the performance of the proposed controller with PID and PIID controllers, numerical examples are presented. Using Ziegler-Nichols tuning rules, all simulation results prove that the performance of the PIIFD controller is better than the performance of the others. K e y w o r d s: fuzzy logic controller, PID, PIID, Ziegler-Nichols, fuzzification, defuzzification