THE CENTRAL ROLE OF AUTOMATION ON MV ELECTRIC POWER DISTRIBUTION

The Energy concept has always been a focal point in human life. In the past, and still today, the majority of energy is generated mainly by the exploitation of fossil fuels as primary energy source. But it is well known how dangerous are the pollutant emissions produced by these fossil plants, bringing to the Climate Change and to the Global Warming, two of the most discussed themes all over the world. For this reason, nowadays the continuous increase of electricity demand is leading to global politics focused on the electrification of consumptions for the new models of distributed generation: it means that the existing electricity distribution network has to be enhanced in terms of Qualitiy of Service performances, in order to allow the improvement of its hosting capacity by keeping always a good level of satisfaction for its customers. About this last statement, it is fundamental to develop the concept of Smart Grid. One of the most important cornerstones of Smart Grids, concerns the electricity distribution network automation: if distribution lines are able to manage independently, they will certainly guarantee a good level of Quality of Service to all customers and they will be able to host new electrical loads expected with the actual and future electrification of consumptions. In this scenario, the most important leader company here in Italy involved in the mission of distribution grids automation is e-Distribuzione: it is part of Enel Group company and it is the responsible of electricity Distribution and Measurement with 1.100.000 km networks in the national area. The main purpose of the present work is to highlight the presence of automation on e-distribuzione electricity distribution grids by showing the obtained advantages from different perspectives. Starting from a first introduction on the concepts of Smart Grid and Distributed Generation, a general analysis of the most important characteristics of MV lines is provided: the distinction between the two main methods of neutral earthing systems is performed, followed by the explanation of protection systems own to e-distribuzione MV distribution lines. At this point, the concept of automation is introduced and the required equipment in Primary and Secondary Substations is illustrated. After that, automation cycles evolution for the fast selection of the faulty grid point is discussed and the five different techniques useful to detect the failed branch are explained (Automatic Reclosure in Primary Substation without automation, FRG technique, FNC technique, FSL and SFS techniques and SHA technique). Finally, the main goal of this work is reached with the highlighting of main benefits brought by automation of MV distribution lines from different point of views: it will be analyzed the positive influence of the increasing automation volume on Quality of Service main KPIs (DIL and NILB), together with a focus on the significant time reduction in the process of failed branch selection thanks to automated devices and a discussion about rewards taken from e-distribuzione for the compliance of QoS targets thanks to the help of its automated MV distribution lines. At the end of this document, there will be also a little chapter specific for the illustration of possible automation failures focusing on critical automated devices.