Integration of solid state transformer with DC microgrid system

Abstract

This paper investigates a Solid State Transformer (SST) based DC microgrid architecture, addressing the design and control of the multiple SST power conversion stages and the power management strategy required for its integration with other microgrid elements, such as storage devices and local distributed generation. The advantages of a SST in relation to conventional low frequency transformers are commonly listed as a substantial reduction of volume and weight, fault isolation capability, voltage regulation, harmonic filtering, reactive power compensation and power factor correction. The SST also constitutes the required infrastructure that will enable DC power distribution to homes and commercial buildings in the near future and provides a more efficient way to integrate storage devices and distributed generation into the electrical grid. In this sense the SST behaves as an energy router, which represents a key element in an intelligent power system. The behavior of the proposed architecture for different operating conditions and disturbances will be assessed through computational simulations in the software MATLAB/Simulink.