State-of-Charge Equalizations Comparison in a Multi-prosumer Environment Based on Real-Time Energy Management Systems with IoT-Support

One essential distributed energy resource (DER) in smart microgrids (MGs) is the Energy Storage System (ESS) based on batteries, which enables many power and energy functionalities. However, when a microgrid includes more than one ESS, or when multiple ESSs interact within a multi-prosumer environment, their charging and discharging processes should be managed to avoid uneven degradation. This paper presents the modeling and implementation of two different strategies for scheduling the DERs using mixed-integer linear programming (MILP) and quadratic programming (QP) in a multi-prosumer grid-connected microgrid. Each prosumer has its own battery-based ESS with various capacities. The proposed strategies were implemented as a real-time energy management system (EMS) in an experimental laboratory Microgrid based on a rolling horizon scheme. The equalization of the ESSs' state of charge (SoC) is achieved in both cases but there is a compromise between cost and execution time. Meanwhile, the IoT-based smart meter allows the EMS to react in real-time to mismatches between predicted and real load.