Towards Quality-of-Service Control of Networked Control Systems: A Switched Time Delay Systems Approach

Abstract

Abstract-The stability and performance of a networked control system (NCS) strongly depends on the communication quality in terms of time delay for example. According to the Quality-of-Service (QoS) concept in modern communication technology, the communication quality can be adapted to the requirements of the network application. This paper presents a first approach to conjointly control the NCS as well as the communication quality on basis of the QoS concept. We assume that the controller together with the time delay is switched to meet control and network performance objectives. Sufficient stability conditions are presented for the resulting switched time delay system based on the concept of piecewise continuous Lyapunov functions and the Razumikhin approach. Simulations and experiments validate the proposed approach.

Switching controller for stabilization of linear systems with switched time-varying delays

“…It means that the control gain switches when the delay crosses the value of 0.05sec. According to the approach in this paper, the decay rate ensuring the exponential stability in every modes are: α 1 = 1.1, α 2 = 0.89 and the maximum exponential values for SU 1 and SU 2 respectively are:…”

“…A common Lyapunov-Krasovskii Functional can ensure the stability with arbitrary switching but it does not always exist. As an alternative, dwell-time based switching is considered in [7] but time delay is not considered, while in [1], [20], the time delay is constant one.…”

“…In general, the stability of the subsystems themselves are not sufficient for the stability of the overall system. A lot of studies have dealt with the stability analysis and design of switched systems [1], [7], [12], [19]. According to Liberzon and Morse, these problems can be divided into three basic problems: (1) Construction of a common Lyapunov functional to guarantee the stability for arbitrary switching sequences [10], [13], [18]; (2) Multiple Lyapunov functions are applied to the stability for certain useful classes of switching sequences; (3) Construction of stabilizing switching sequences.…”