Analyzing Replay Attack Impact in DC Microgrid Consensus Control: Detection and Mitigation by Kalman-Filter-Based Observer

This paper presents a Direct Current (DC) Microgrid with a consensus-based secondary control strategy to efficiently manage the microgrid, ensuring precise voltage regulation and fair power distribution among Distributed Energy Resources (DERs). The consensus approach employs a communication network to establish a Cyber layer for DER information exchange and harmonize the entire system to achieve a common goal. However, this cyber layer’s vulnerability could destabilize the interconnected control system and lead to the whole system being unsynchronized. The paper explores replay attacks conducted in the path of the communication link between interconnected Distributed Generation Units (DGUs), demonstrating their impact on secondary control using simulations and real-time experiments. A method leveraging Distributed Kalman Filter observers for attack detection is proposed which requires low computational demand to suit the real-time application, while an attack mitigation technique using observer-generated residues with the optimal condition is implemented. Validation is conducted through both MATLAB simulations and real-time OPAL-RT emulation, confirming the proposed system’s effectiveness.