Modeling and Design of Solid State Smart Transformer for Microgrid

While the techno-economic feasibility of solid state transformer (SST) is constantly under question, some of the leaders in power sector have recognized the potential of the technology and have started efforts of commercialization. One of the important advantages of SST is its ability to integrate to low voltage dc grids and vehicle-to-grid (V2G) technology. One of the key area of research in this field is to develop an accurate model for the SST to demonstrate the control capabilities and perform the dynamic analysis of the system. Although detailed models have been proposed for individual components of SST, only lower order averaged models are used for modelling the composite system. In this article, an accurate composite model of SST that incorporates high switching frequency is developed. The model is controlled using a conventional voltage control technique and a with a newly proposed power control technique. The control methods are then used accordingly to develop applications to integrate electric vehicles with its battery charging station in a dc microgrid.