Installation of many distributed generations (DGs) could be detrimental to the power quality of utility grids. Micro grids facilitate effortless installation of DGs in conventional power systems. In recent years, DC microgrid have gained popularity because DC output sources such as photovoltaic systems, fuel cells, and batteries can be interconnected without ac/dc conversion, which contributes to total system efficiency. Moreover, high-quality power can be supplied continuously when voltage

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... or blackouts occur in utility grids. It is proposed a "low-voltage bipolar type DC microgrid" and described its configuration, operation, and control scheme, through simulations. However, DC micro grids should have two or more energy storage units for system redundancy. Therefore, we modified the system by adding another energy storage unit in simulation model. Several kinds of droop controls have been proposed for parallel operations, some of which were applied for ac or dc micro grids. If a gain-scheduling control scheme is adopted to share the storage unit outputs, the storage energy would become unbalanced. This project therefore presents a new voltage control that combines fuzzy control with gain-scheduling techniques to accomplish both power sharing and energy management. The simulation results will be obtained for the DC distribution voltages were within 340 V ± 5%, and the ratios of the stored energy were approximately equal, which implies that dc voltage regulation and stored energy balancing control can be realized simultaneously in MATLAB Software.