Practical analysis and design of a battery management system for a grid-connected dc microgrid for the reduction of the tariff cost and battery life maximization

Abstract

This study is focused on two areas: the design of a Battery Energy Storage System(BESS) for a grid-connected DCMicrogrid and the power management of that microgrid. The power management is performed by aMicrogrid Central Controller (MGCC). AMicrogrid operator provides daily information to theMGCC about the photovoltaic generation profile, the load demand profile, and the real-time prices of the electricity in order to plan the power interchange between the BESS and themain grid, establishing the desired state of charge (SOC) of the batteries at any time. Themain goals of the powermanagement strategy under study are to minimize the cost of the electricity that is imported from the grid and to maximize battery life by means of an adequate charging procedure, which sets the charging rate as a function of theMG state. Experimental and simulation results inmany realistic scenarios demonstrate that the proposedmethodology achieves a proper powermanagement of the DCmicrogrid.