Disruptive Effects of Denial-of-Service (DoS)Attacks on Microgrid Distributed Control: Altered Communication Topology, Voltage Stability, and Accurate Power Allocation

Distributed control is an effective strategy for synchronizing actions among numerous distributed generators (DGs) within a microgrid. This method adheres to specific communication network topology requirements, following the principles of Graph theory. Unexpected changes to this network structure can disrupt the Laplacian Matrix, resulting in unusual eigenvalues, and ultimately, disrupt the function of the controller, leading to operational disharmony due to a deviation from Graph theory principles. Denial-of-Service (DoS) attacks represent a significant cyber threat capable of altering the Laplacian matrix by blocking communication channels, resulting in structural changes to the communication network. Such unforeseen changes can leave the controller with incomplete neighbor information, which is pivotal for making control decisions. Decisions made without this vital neighbor data can significantly threaten grid stability. This paper demonstrates how the Laplacian matrix adapts its formation under normal conditions, maintaining stability through concurrent updates of the adjacency and diagonal matrix, thus preserving eigenvalues within the stability region. Conversely, it depicts the impact of DoS attacks on a cyber-physical microgrid. These attacks block communication links among DG units, leading to unusual Laplacian matrix formation due to the inability to update the diagonal matrix, causing eigenvalues to fall into an unstable region. The impacts of this unusual formation lead to abnormal control actions, disrupting voltage stability and the allocation of power among Distributed Energy Resources (DERs) has been validated by MATLAB simulation.