Decentralized pole-placement using generalized sampled-data hold functions

This paper presents a novel sequential technique for pole-assignment in linear time-invariant (LTI) decentralized control systems. Generalized sampled-data hold functions (GSHF) are used as local controllers to place the modes of the equivalent discrete-time closed-loop system in the desired locations in the z-plane. These locations are assumed to be obtained by using a proper mapping from the continuous-time domain. The GSHFs are obtained one at a time, in a sequential fashion. In other words, each local controller is designed for the equivalent discrete-time closed-loop model associated with the previously designed controllers. While no bound is provided on the intersample ripple, the convergence of the samples to zero ensures that the intersample values will also approach zero as time increases. The main characteristic of the proposed method is that unlike conventional pole-placement algorithms, the design complexity here does not increase after each local controller is obtained. A numerical example is provided which confirms the efficacy of the proposed pole-placement technique.