Using timed automata for modeling, simulating and verifying networked systems controller's specifications

The development of dependable controllers can be a very complex task. For this purpose, some synthesis and analysis modern computational techniques can be used. In this paper, simulation and formal verification analysis techniques are used in a concurrent way in order to validate formal communication requirements of generic object oriented substation event and sample value communication protocols from the IEC 61850 standard. Because these techniques are used in a complementary way, the formalism and tools used for both are the same: timed automata for modeling, and UPPAAL model checker for performing simulation and formal verification tasks. Also, we show that the use of timed automata formalism is suitable for modeling the controllers' specifications, specifying the time requirements for information exchanging taking into account networked controllers, and, as it is a non-deterministic formalism, for analyzing the plant behavior. The concepts developed in this study were successfully tested in an application in the control system of an automated people mover.