Protection Strategies for AC and DC Microgrid – A Review of Protection Methods Adopted in Recent Decade

In last few decades, microgrid has emerged an interesting and intelligent approach by containing its prospective framework using smart grid protocols. One of the technical issues in implementing microgrid in smart grid environment is to design a distinct protection scheme with the ability to meet the protection requirement in all modes of operation. The motive for this study is to address a technical outlook in protection strategies of microgrid and the challenges to achieve them. Initially, the currently existing protection techniques of AC microgrid followed by DC microgrid are discussed. Since the conventional protection technique cannot be used in DC microgrid directly as there’s no zero crossing in DC systems and bidirectional power flow, it needs more attention in proposing a protection strategy for DC. Therefore, this leads to the innovation of adaptive protection in microgrid where the implementation of communication infrastructure makes the system smart. Thus, this paper focuses on detailed literature on protection scheme for AC and DC microgrid.