The Status of DC Micro-Grid Protection

AC microgrids are a convenient approach to integrating distributed energy systems with utility power systems. On the other hand, DC micro-grids can lead to more efficient integration of distributed generation. They are the preferred topology for present shipboard, aircraft and automotive power systems and hold promise for future environmentally friendly office buildings, homes, rural areas and industrial power parks. However, standards, guidelines, practical experience and cost effective implementations for DC system protection are well behind practices in AC system protection. This paper presents a comprehensive overview of the body of research on protection of DC micro-grids, presented with a goal of identifying and advancing the field. The paper presents a discussion of the current status of dc micro-grid protection, including the use of electro-mechanical circuit breakers, solid state circuit breakers, protective system design, ground fault location and fault isolation.