Use of upper bound delay estimate in stability analysis and robust control compensation in networked control systems

TL;DR

This paper proposes a unified approach to analyze and improve the stability of networked control systems by estimating upper bound delays using network calculus and applying this in stability analysis and control compensation.

Contribution

It introduces a method to estimate upper bound delays in switched Ethernet networks and integrates this estimate into stability analysis and control strategies.

Findings

Delay estimation improves stability analysis accuracy.

Using upper bound delay enhances control compensation effectiveness.

The approach is applicable to Ethernet-based networked control systems.

Abstract

Recent interest in networked control systems (NCS) has instigated research in various areas of both communication networks and control. The analysis of NCS has often been performed either from the network, or the control point of view and not many papers exist were the analysis of both is done in the same context. Here a simple overall analysis is presented. In the paper the procedure of obtaining the upper bound delay value in the switched Ethernet network is proposed and the obtained delay estimate is used in stability analysis of the feedback loop and in the control compensation. The upper bound delay algorithm is based on the network calculus theory, the stability analysis uses the small gain theorem, and control compensating strategy is based on Smith predictor, where however the upper bound delay is utilised in obtaining the delay estimate.