Distributed Control Microgrids: Cyber-Attack Models, Impacts and Remedial Strategies

Microgrids are rapidly evolving as cyber-physical systems to have interoperability among the connected sources. These cyber-physical microgrids (CPM) are highly dependent on communication networks for realizing power control strategies, making them highly vulnerable to cyber intrusions. Cyber-attacks are usually intended to meddle with data availability, integrity, and confidentiality. This paper first summarizes mathematical models of commonly occurring cyber-attacks, which include denial of service, false data injection, replay, and covert attacks. Further, a brief discussion about their impacts on distributed controlled AC and DC CPM is detailed. As consensus among the sources is an essential requirement in distributed CPM, the technical and physical challenges arising in achieving the consensus due to different attacks in AC and DC microgrids are analyzed using simulation case studies. Viewing the importance of security assessment and enhancement, state-of-the-art cyber defense strategies for AC and DC CPM are discussed. For better understanding, few defense methods are simulated and validated on CPM. Finally, this paper identifies a few challenges in security and presents some basic resilient strategies along with future research scope in this field.