Coordinated Control Strategy for a DC Microgrid with Low Bandwidth Communication

The control and management of AC and DC microgrids is a major area of research addressing some of the key challenges like the integration of renewable energy sources (RES), source optimization, and stability issues etc. Numerous microgrid control strategies have been proposed and examined earlier. However, the control becomes even more susceptible to instability due to the participation of intermittent and dynamically diverse renewable sources like solar photovoltaic (SPV), wind turbine etc. Involvement of a large number of distributed energy sources demands significantly coordinated control based on a high bandwidth communication network to sustain uninterrupted operation under every working condition. This paper presents a coordinated control strategy based on a low bandwidth communication link for the management of a dc microgrid that permits execution of distinct operating states such as black-start or restoration of the microgrid, source, and power optimization during steady state operation and emergency conditions etc. An overview of the implementation of the proposed control strategies in a dc microgrid comprising of three sources along with some key experimental results is presented in the paper.