Synchronization conditions and Real-time constraints in co-simulation and Hardware-in-the-Loop techniques for Cyber-Physical Energy System assessment

Co-simulation and Hardware-in-the-Loop, as well as the integration of Hardware-in-the-Loop to a co-simulation framework are innovative approaches that can get a step closer to a complete and realistic assessment and validation of cyber-Physical energy system (i.e. smart grid). While the coupling techniques and the master algorithms ensure good functionality of the experiment, the whole framework has to follow a rigorous time semantic so that the results would be accurate and meaningful. In this paper, we present a formalization of the synchronization aspect in co-simulation and Hardware-in-the-Loop. Using this formulation, we propose synchronization and real-time conditions under which a co-simulation/Hardware-in-the-Loop framework is well-posed and correctly synchronized. Moreover, the classical real-time constraint in Hardware-in-the-Loop is relaxed for more flexible application. The proposed formulation is illustrated via an cross-infrastructure implementation of secondary control in micro-grid, with integration of remote controllers to real-time co-simulation framework. (C) 2019 Elsevier Ltd. All rights reserved.