A simple and direct method for reducing order of linear interval systems

This paper proposes the direct reducing order method of linear interval systems for obtaining simple models of complicated physical electronic systems. In this paper, the electronic system's behavior is governed by a high order linear interval differential equation is assumed. The four fixed Kharitonov's differential equations associated with the original interval system and interval reduced model are obtained. The coefficients of the four fixed Kharitonov's differential equations, with a set of specified initial conditions are found by matching the integrals of the square of the output. Finally the coefficients of the interval reduced model are obtained. A numerical example is included in order to demonstrate the effectiveness of the proposed method.