'Smart Grid Lambrate' project: microgrid active management and control from a Primary Substation

摘要

In the framework of “Smart distribution” demonstration projects, launched by the Italian Energy Authority and focused on MV networks, A2A Reti Elettriche, city of Milan Distribution System Operator (DSO), has set up an implementation of a smart distribution concept to a real MV network in the Milan urban area (Lambrate Smart Grid Project). The project is aimed at restructuring the MV network underlying the Lambrate Primary Substation (220/23 kV) involving 21 Secondary Substations and 5 Active Users, including RSE’s Distributed Energy Resources Test Facility (RSE DER-TF). This facility is one of the distinctive features of Lambrate Project in comparison to other distribution pilot projects. It is a LV microgrid with a configurable network topology covering a 20.000 m2 area. Several generation systems (from RES to CHP), storage systems and loads are connected. With its own control system, it can be considered as a dispatchable unit by the DSO extending the range of possible experimental tests; specific functions such as remote disconnection, active and reactive power control or fault simulations, difficult to perform with other Active Users, can be easily and flexibly performed. Features implemented include advanced network automation (i.e. selective fault detection and fast network reconfiguration), multi-vendor Intelligent Electronic Devices (IEDs) interoperability by IEC 61850, DERs remote disconnection operated by the DSO, selective protection systems interlocking, voltage and frequency regulation by DER units remote active and reactive power control, DERs management optimization. Primary Substation and Active Users data connection is based on public ADSL with Layer Two Tunneling Protocol (L2TP) to exploit the potential of the IEC 61850 standard. After the project description, the micro grid system architecture, installed equipment, control and management functions are presented in this paper, and significant experimental results are discussed.