Smart grids for power quality improvement

In the context of an increasing penetration of Distributed Generators, Distribution System Operators of any size are facing the transition to the Smart Grid, investigating how its role will change in the future. This work will present a comprehensive analysis of how a DSO would face the Power Quality issue in the future thanks to the technologies of the smart grids. The activities have been carried out in collaboration with the DSO of the city of Terni, namely ASM Terni S.p.A. (ASM) and its productivity unit Terni Distribuzione Elettrica (TDE) which owns and manages the distribution network in the municipality. During the work lifespan, there has been the opportunity to evaluate smart technologies and carry out grid analysis in a real environment, notably, the Medium Voltage distribution network of TDE and the living laboratory at ASM headquarters. Some activities have been totally developed within this work whilst others have been carried out in the context of some European projects that have been founded or cofounded by the Innovation and Research & Innovation actions for Energy sector established by the European Commission and involve ASM as consortiums’ partner. The consortiums of these projects have designed, produced and installed in the ASM facilities cutting-edge devices and software solutions for the distribution network and the electrical customers; this work has evaluated their contribution on the power quality. Considering Smart Grid definition, it is important to understand what is currently Power Quality for a DSO; in this respect, the main objective of a DSO is to reduce the interruptions, secondly abnormal voltages are also an issue as well as the reduction of technical losses (i.e., increasing the energy efficiency). However, DSOs are focused on outages since it means the lack of its main services to the users, namely, electrical energy, which also dramatically affects other crucial services such as Telecommunication, heating, cooling, water, industrial processes. Moreover, the Italian DSOs, which have been studied in this work, receive monetary incentives or have to pay penalties if the outages, recorded in a year, are less than defined objectives or more than these. Investigating on reduction of outages implies an increase of resilience of the distribution network, as the ability of a DSO to promptly react when a foreseen event and rapidly restore the network to the normal status. The reduction of outages are investigated in this work considering contributions on the network development plans and on real time operations. Therefore, in a first stage, the analysis of a component widely installed in the Italian distribution networks has been carried out; notably thermal analysis of MV cable and joint is performed in order to investigate on the anomalous number of faults on this component that have been recorded in summer during last years. Moreover, the distribution network of TDE has been analyzed with a Resilience assessment software and its related procedures for improving and validating the development plan of the distribution network. The homemade software, developed during this work lifespan, can be used for any networks and the resilience can be assessed for any type of treats. The last stage consists of theoretical evaluations and demonstration activities of innovative solutions that could help the DSO to reduce congestions in the network during real time operation (i.e., to prevent and foreseen outages). The enabling tools that have been used are Real time Smart Meters installed in the networks and proper management software. In this respect, main concern of this work has been the interaction between DSO and Aggregator who manages a pool of users in the Demand Response campaigns. The evaluated mechanisms allow DSO to increase hosting capacity of the network in respect of Photovoltaic plants (PV) and Electrical Vehicles (EV). Moreover, this work presents assessment on cooperation mechanism between DSO and a rural microgrid by means of a proper ICT infrastructure. In the context of power quality improvement thanks to the Smart Grids, further technologies have been evaluated in this work. With respect to the energy efficiency and voltage control, the support from storage systems have been studied by means of tests on the field, as well as it has been assessed the support from EV charging stations coordinate with the implementation of smart contracts leveraging on blockchain technology.