Power converters as interface and integration systems in hybrid AC/DC smart grids

Hybrid AC/DC grids represent promising solutions capable of combining the advantages of AC distribution systems with the concept of DC electricity distribution. The widespread diffusion of renewable generation, DC loads, and storage and the possibility to connect them to AC or DC grids focus the attention on reliable conversion interfaces. This chapter aims to focus on DC/DC, zDC/AC converters, and solid-state transformers as interface systems in hybrid AC/DC smart grids. Topologies and electrothermal behavior are analyzed by available models in order to quantify thermal aspects and stresses affecting converters performances. A novel methodology is proposed to analyze the reliability performances of DC/DC, DC/AC interface, and solid-state transformer systems. This methodology is applied to a modified IEEE 13-bus power system, and the obtained results are presented.