Decentralized control of DC microgrid clusters

This paper explores the interconnection of multiple microgrid with “tie-line”. Tie-line control can be managed to control the power flow from microgrid and voltage at respective microgrid buses at the point of interconnection. Formation of such DC microgrid cluster ensures higher reliability of power supply and flexibility to manage distributed energy resources and loads in the system. Two identical MGs consist of photovoltaic (PV) and battery units interfaced by power electronic converters. The bus voltages of two identical DC microgrids act as indicator for the power flow monitoring the supply-demand balance. A decentralized control approach is proposed to control each microgrid and bus voltage fluctuation in allowable range. Furthermore, a mode adaptive decentralized control approach is proposed for seamless mode transition in order to assign microgrid operation modes and for the power management of DC microgrids. The effectiveness of the proposed concept is shown through simulation results.