Supervisory Control of Networked Timed Discrete Event Systems and Its Applications to Power Distribution Networks

This paper treats the problem of existence of a controller for networked-timed discrete-event systems. The results are new and useful for any networked discrete-event system for which it is important that time be explicitly considered in the model. We assume that a controller (supervisor) communicates with the system to be controlled via a shared communication network. Delays and losses in communication systems and their impacts on control are investigated. Under the assumption that the delays and losses are bounded, we derive a necessary and sufficient condition for the existence of a controller. The condition is expressed as network T-controllability and network T-observability, which are defined in this paper. We apply the results to power distribution network management, and illustrate the application using a 33-node (bus) test system, where the objective is to ensure that the total substation transformer power stays within prespecified safety limits.