Sayyad Nojavan

Distribution networks are deeply involved in the challenge for the integration of renewable energy sources (RES), in which their electricity production depends upon meteorological conditions and/or the time of the day. Therefore, the persisting growth of variable renewable generation— predominantly on distribution level—is gradually altering the operating condition of distribution networks. From the distribution system operator (DSO) point of view, the new electricity generation mix is causing a dramatic revolution of their distribution systems. Furthermore, the presence of bi-directional power flows and the increasingly occurrence of reverse power flow on distribution transformers are compromising the traditional passive management of distribution networks, particularly for voltage regulation and protection systems. At the same time, DSO needs to be ready to deal with external inputs coming from the “smart world” that will transform the loads from simple points of electricity absorption to effective players in the distribution system, with new requirements but also with a new capability of interaction. The flexibility of loads can be regarded as one of the distributed energy resources (DER) issues. Also, energy storage systems (ESS) are valuable components of the future distribution system, thanks to their ability to increase the flexibility of the overall system and to provide a wide range of services to the DSOs and to the customers with the final goal of mitigating the negative effects of RES. Services provided by ESS may be such as deferment of network investments, energy losses reduction, voltage regulation, reactive power balance, congestion overcoming, etc. ESS will allow both load profile flattening and solving extra production conditions, especially if they are connected to critical nodes of the network. The electricity distribution is relying more and more on the intelligent active management of the system instead of traditional absence of operational act