Analysis and Design of the Protection Scheme for a LVDC Microgrid

Abstract

The growing diffusion of renewable energy sources is leading to a considerable revision of the distribution network. In this context, the adoption of direct current distribution grid can bring benefits to the hosting capacity and energy efficiency. However, the protection of such network involves many challenges, especially in case of LVDC microgrids with more than one feeder. The traditional protection schemes used for AC grid are not able to isolate faults and to protect the components of the DC grid. This paper deals with the analysis and design of the protection scheme for a low voltage DC microgrid, in presence of different renewable generators, energy storage systems, loads and front-end converter with the AC grid. The proposed centralized protection scheme overcomes issues of fast fault clearing time, cost effectiveness and selectivity in the case of pole-to-pole fault.