A Virtual Queuing based Algorithm for Delays Evaluation in Networked Control Systems

Boussad Addad (1) , Saïd Amari (1) , Jean-Jacques Lesage (1)

1 LURPA - Laboratoire Universitaire de Recherche en Production Automatisée

In this paper, an approach to evaluate time performances of networked control systems (NCS) is presented. Switched-Ethernet with Client/Server protocol is considered for communication. As a result, the reactivity of these NCS is not only affected by the network delays but also by the field devices due delays. Obviously, all of them have to be taken into account to evaluate efficiently the NCS reactivity. So, by including some preliminary results, we propose an overall study in an effort to achieve this aim. First, we model the traffic of the NCS and provide formal proofs to characterize the scenarios leading to the worst delays. Subsequently, we develop a virtual queuing based algorithm (VQA) to search these scenarios and deduce the corresponding delays. Through a practical case study, it is shown how VQA fits experimental observations both quantitatively and qualitatively.

Mots clés: Networked Control Systems; Client/Server Protocol; Switched Ethernet; Delays Evaluation; Virtual Queue

Domaines: Automatique

Boussad Addad, Saïd Amari, Jean-Jacques Lesage. A Virtual Queuing based Algorithm for Delays Evaluation in Networked Control Systems. IEEE Transactions on Industrial Electronics, 2010, pp.9. ⟨10.1109/TIE.2010.2098358⟩. ⟨hal-00546532⟩