Stability of Multi-Rate Internet-Based Control Systems with Time-Delay at Feeback and Feed-forward Channels

Internet-based control is the way of monitoring and adjusting plants from a remote site over the Internet. The major challenge of this new kind of control systems is how to deal with Internet time delay. Our recent study illustrated that there is a great potential to overcome Internet time delay from the control system architecture aspect such as by using multi-rate control schemes. In this paper, we formulate a new class of dual-rate control systems with Internet time delay at both feedback and feed-forward channels and investigate their asymptotic stability properties. Some new necessary and sufficient criteria of asymptotic stability for such dual-rate control systems are established. Two examples are given to illustrate the effectiveness of the theoretical results.