A look at the role and main topologies of battery energy storage systems for integration in autonomous microgrids

This paper presents a survey over the main topologies of the battery energy storage systems (BESS) and they role in the operation of microgrids (MG), in the picture of the future smart grids development. The frequency control issue in autonomous MG in comparison with a classical power system is investigated and the BESS purpose on this line is enlighten. The BESS´s secondary functions like voltage control (RMS and shape) or short-circuit capability, which help the MG to behave as a classical grid, are depicted. The BESS includes an energy storage element and a power electronics converter that is the focus of this paper. Two main converter structures are studied and the advantages and disadvantages of each one are compared. Besides the hardware analysis, a short review of the control solutions for BESS is performed.