System methodologies for situation awareness and risk management for critical infrastructure protection

The Mixed Holistic Reductionist Approach is a methodology that merges the holistic and the reductionist techniques trying to conserve the pros. The aim is the modelling of critical infrastructure interdependencies and the assessment of impact due to physical failures and to cyber threats. This approach can be applied both in distributed and in centralised contexts. The distributed framework is mandatory if the communication among control centres is peer-to-peer. In order to manage also cyber threats, Situation Awareness models and techniques help in order to classify faults and failures. In fact, Data Fusion methodologies, as Evidence Theory, can detect the most probable cause of faults happened in facilities and, therefore, we uses the other information, coming from Evidence Theory results, as another input for the MHR approach. The state estimation is one of the key functions of SCADA systems for grids. In order to identify the state of the system, state estimation helps in accurate and efficient monitoring of operational constraints. The ability to provide a reliable state can also help in contingency analyses and in the required corrective actions. The smart grid context is quite different respect to traditional distribution grid, starting from different topology features, so a new approach to state estimation is mandatory