Microgrid Cluster Energy Management with a PLC

Abstract

Microgrid clusters (MGCs) provide an opportunity for system operators to enhance efficiency, resilience, and reliability of energy systems. MGCs can combine direct current (DC) and alternating current (AC) technologies by integrating different power generation, consumption and storage technologies, thus offering flexibility and resilience to individual microgrids (MGs). However, verification of practical control systems for MGCs is required to ensure robustness and efficiency of the power dispatch. This work contributes to this effort by presenting, implementing and verifying a control system for an MGC. This MGC comprises separate DC and AC MGs interconnected to a local grid: the DC MG incorporates DC loads, a wind turbine, a fuel cell, an electrolyzer, and an ultracapacitor; and the AC MG comprises AC loads, an electrical battery bank, and a photovoltaic power plant. The control system uses a dynamic centralized energy management system (EMS) that coordinates power dispatch and energy distribution between all energy storage systems and local device controllers. The control system, specifically the EMS, is evaluated across different operating scenarios in an experimental validation environment composed of an OPAL-RT unit and a SIMATIC ET 200SP Open Controller PLC. The results show that the implemented EMS exhibits robust real-time behavior across different operating scenarios.