축차 제어기에 관한 강인 안정성 조건

Abstract

This paper deals with the robust stability condition of the closed-loop system with a low-order controller which is obtained via balanced truncation for an originally designed high-order controller. It is assumed that controller reduction error and plant``s uncertainty are represented by using coprime matrix fractions. The stability condition is derived from the small gain theorem. It is shown that the resulting robust stability condition is better than known results. As a special case, the nominal stability condition for the low-order controller is also dealt with.