Future energy networks may need to have increased cross vector coupling as well as renewable generation to meet the requirements of carbon reduction. This will introduce complexities to the task of network operation especially if this must be achieved without cross vector communication. In this research, the mutual benefits of integrated operation of gas and electricity networks at both transmission and distribution levels in terms of techno-economic-environmental parameters using a whole system approach were investigated. A simulation framework was developed for this purpose and a case study of integrated gas and electricity networks at both transmission and distribution levels as well as several scenarios were designed. This also allowed an assessment of the impacts of transmission systems on distribution systems and vice versa. It was observed that each coupled network could support the operation of the other network in case of occurrence of any faults, and change of operating conditions or renewable generation. In the considered cases, integration of network operation increased the cost of operation of the networks, however, the integrated networks could continue to meet demand and decrease the carbon footprint.

A framework is introduced for monitoring the interrupting faults in the timed discrete events systems. We introduce the notion of acceptable behavior of the system subjected to these faults: permanent or intermittent. The acceptable behavior of a system is modeled by a stopwatch automaton. The timed sub-spaces in the locations of the automaton delimit exactly the range of the acceptable behavior. They are synthesized using the techniques of reachability analysis of stopwatch automata in a way to detect the system faults as early as possible.

This paper extends the notion of residuals for fault detection, well known in the continuous system to the timed discrete events systems. The aim is to design the fault indicators, two problems are considered. Firstly, the dynamics of clocks which monitor the system must be sensible to the behavior change resulting from a fault. Secondly, we must specify the inequality clocks constraints for which the system is normal as long as they are satisfied. We introduce the notion of acceptable system behavior modeled by stopwatch automata. This behavior is supervised by two clocks for each interruptible task of the system. The time sub-spaces in the stopwatch automaton locations delimit exactly the range of acceptable behavior. They are synthesized using an algorithm based on the reachability analysis techniques of stopwatch automata. One of the main results of designing this time space is the detection the system faults as early as possible.