Modified PI Control using Model Driven Control for Certain Class of Non-minimum Phase Systems

Abstract

In this paper, we examine PI (Proportional-Integral) control using model driven control for certain class of non-minimum phase systems. PI control systems work as one of powerful methods for controlling several plants. However, PI control remains two difficulties. One is that there exist plants which cannot be stabilized by PI controller. The other is that when P-parameter and I-parameter in the PI controller is adjusted using previously proposed methods, the sets of P-parameter and I-parameter, which guarantee the stability of PI control system, are related to each other. Therefore if P-parameter is changed, the set of I-parameter which make the feedback control system stable is also changed. If the sets of P parameter and I-parameter are independent each other, then we can easily settle P-parameter and I-parameter in the PI controller to achieve desirable control specifications. However, no paper gives the sets of P-parameter and I-parameter which are independent each other. The purpose of this paper is to overcome these problems and propose a modified PI control systems such that the stability of control system is guaranteed and the sets of P-parameter and I parameter, which guarantee the stability of PI control system, are independent. The modified PI control systems is built based on fusion of the idea of the model driven control and the parametrization of all stabilizing controllers for certain class of non-minimum phase systems. A numerical example is illustrated to show the effectiveness of the proposed method.