Optimal Performance Analysis for Networked System with Quantitative Control Input Over Feedback Channel

Abstract

Networked control systems (NCS) have become an emerging and important research area given the rapidly developing network communication technology. Numerous studies in this area concentrate on the stability of control systems, while little has been done on its performance analysis, especially the index of an optimal control system. We fill this gap here by analysing the optimal tracking performance for an NCS that has quantitative control inputs over feedback channels. We design a dual-degree-of-freedom controller along with an optimal control system, by applying the Youla parameterization method based on the time domain and coprime decompositions. The proposed methodology is assessed by numerical simulations. The system's tracking performance is found to be deteriorated by the unstable poles and non-minimum phase zeros of the controlled object, as well as by quantization signal errors. These findings are beneficial for analysing and designing practical control systems.