Suitability of adaptable state feedback for keeping prescribed control quality under changing operation conditions

Abstract

A state variable feedback technique is usually used when controlled system dynamics is to be changed in a desired way. The results are very good provided that the linear state space representation used in the design is sufficiently valid in the whole operating range. In the paper, we present a case study of a tank cascade with changeable static and dynamic properties. When these changes are so significant that superior PI or PID controllers require resetting, it is advantageous to adapt the proportional state variable feedback. We assessed the impact of the feedback gain changes resulting from changes in the linear state model parameters used in the design of the gains.