The term of Microgrid Control refers to the application of control theorems and relevant technologies for stabilizing and enhancing the performance of microgrids in real-world operations, following various disturbances such as the loss of distribution of generators (DGs) and load units. This issue encompasses not only the internal control performance of microgrids and the connection/disconnection procedures to limit negative dynamic impacts on the power network but also grid support functionalities that enhance the overall operation of distribution networks. Some of the most critical microgrid control issues include active and reactive power sharing, synchronization methods, voltage and frequency regulation services, emergency control, cybersecurity, power control and energy management. Recent findings in confirm that the current well-known hierarchical 3-layer control scheme which is initially inspired by the conventional power system frequency control layers is not sufficient for classifying different microgrid control issues and covering all required control loops. This speech, in addition of presenting a critical review, presents a generalized 4-layer hierarchical control framework to address the existing shortcomings.
