Robust Covert Attack Detection in DC Microgrids: A Novel Approach to Cybersecurity

The widespread adoption of distributed dc microgrid (DCMG) structures, driven by the increasing integration of renewable energy resources, has introduced vulnerabilities for possible cyber intrusions due to the incorporation of communication architecture. These cyber-attacks, once infiltrated, can either destabilize the complete system or remain undetected by maintaining operational control objectives despite the presence of an attack. This article presents a method for the local detection of such sophisticated covert attacks targeting DCMG actuators. A robust, converter-level detection metric is proposed that relies on both measured and internal states of each node. In contrast to existing methods, the proposed metric is explicitly designed to remain invariant to line and load variations, ensuring high sensitivity to attack vectors alone. In addition, a detection algorithm based on a finite state machine (FSM) framework is introduced to guarantee accurate and consistent identification of genuine attacks. The stealthiness of these covert attacks and the efficacy of the proposed detection method are validated through simulation and experimentation on a four-node DCMG laboratory prototype.