DC Microgrid: A Comprehensive Review on Protection Challenges and Schemes

The development of microgrids can prove to be a game changer in the realization of future smart grids. The increasing trends of automation in domestic loads and smart homes have increased the penetration of DC loads at the distribution level. Hence, the development of a low- or medium-voltage DC microgrid seems the need of the hour to match this changing scenario. Another point is that the various distributed generation (DG) sources like PV, batteries, fuel cells, etc., also provide energy in DC form. Hence, integrating these sources into the DC system also becomes convenient as the power conversion at each point of connection will no longer be needed. But, due to the lack of universally accepted standards and technological advancements, the implementation of DC microgrids is still limited to very small-scale usage. The unavailability of an efficient and reliable protection system is one such issue that is hindering the implementation of DC microgrids on a larger scale. Therefore, a thorough examination of the several DC microgrid protection difficulties and challenges is necessary. Thus the purpose of this article is to provide a comprehensive analysis of the protection challenges, and the currently available protection schemes for DC microgrids and to highlight the gaps for future research to enable the development of a more reliable and efficient protection system.