Full-State Feedback Cyber-Secure Control for Achieving Global Robustness in AC Microgrids

With the rapid expansion of smart devices and the digitalization of microgrids (MGs), cyber-attacks have become an increasing concern, posing significant threats to the security and stability of microgrids. Various secure control approaches have been developed to enhance microgrid stability and mitigate the impact of cyber-attacks. However, current security research on microgrids often neglects the coupling effects among distributed generations (DGs) and the influence of line impedance, primarily focus on local DG perspective. As a result, control approaches targeting individual DGs may be ineffective in maintaining the global robustness and stability of the entire microgrid under attack conditions. To address this challenge, this paper proposes a new full-state feedback control strategy from a global perspective to mitigate false data injection attacks (FDIAs) and achieve precise voltage tracking. First, voltage tracking and stability issues under conventional control during cyber-attacks are analyzed. Next, a cyber-secure control method is introduced based on full-state feedback, incorporating additional controller states to achieve the attack mitigation. The stability analysis for individual DGs and the corresponding controller design are then presented. Furthermore, the global robustness of the proposed method-accounting for coupling effects, line impedance, and cyber-attacks across the entire AC microgrid-is demonstrated. The effectiveness of the proposed cyber-secure control approach is validated through hardware-in-the-loop (HIL) testing on a dSPACE-based microgrid testbed.