Abstract

The increasing incorporation of energy storage and electric vehicles to the grid and the injection of variable renewable energies and hybrid microgrids will impose an important challenge to the transformer design and operation. Solid state transformers become a suitable alternative to address these issues due to the high controllability they perform. Particularly, modular solid state transformer are the preferred choice at distribution level due to the high voltage rating, reliability and fault tolerance they feature. In this paper a modular solid state transformer based on two modular multilevel converter connected by a series of isolated dual active bridges is proposed. The proposed topology is analyzed and mathematically modeled, and a suitable controller is designed. Simulations results shows the performance of the proposed topology and control scheme.