A NDO Based Attack Detection Observer and Isolation Strategy in Distributed DC Microgrid with FDIA

Abstract

In this paper, an isolation scheme is proposed to mitigate adverse effects of false data injection attack (FDIA) in cyber layer of distributed DC microgrids. Firstly, the attack signal in communication link is effectively estimated by the nonlinear disturbance observer (NDO). Secondly, an isolation mechanism is designed to distributively insulate the misbehaving agent of cooperative control, and further to mitigate adverse effects on voltage regulation and power sharing in DC microgrids. Thirdly, considering the changes in load distribution during the process of isolation, a domination controller for stabilizing DC/DC boost converter is introduced to ensure the rapid voltage convergence with accurate tracking over a wide operating range. Simulation results are conducted on an islanded DC MG test system to verify the effectiveness of the proposed scheme.