A unified power delivery solution for integrating DER into distribution networks through VSC based DC system

Abstract

A new power delivery strategy is proposed in this paper. It relies on integrating distributed energy resources (DER) to AC distribution networks through a multi-terminal voltage sourced converter (VSC) based DC system. To accomplish this, a new converter topology is designed. This topology integrates both AC and DC networks and is unified for different voltage and power levels. It allows full power controllability yet has a compact monolithic and scalable structure. It enables economical gradual upgrade to next generation DC distributed generation (DC-DG) starting from already established AC networks. A simulation case study of a 3.7 MW converter in an islanded microgrid is presented to demonstrate the underlying concept and the feasibility of its implementation.