Cyber-Resilient Cooperative Control of Bidirectional Interlinking Converters in Networked AC/DC Microgrids

Bidirectional interlinking converters (BICs) are building blocks of the networked ac/dc microgrids (ac/dc NMGs). Such BICs are controlled using the communication assisted cooperative control thus forming tightly coupled cyber-physical systems (CPSs). One of lethal problems in such CPS is its vulnerability to cyber-attacks. In this article, a cyber-resilient cooperative control for BICs in ac/dc NMGs is proposed to enhance the system resilience under false signal injection attacks. The proposed control can maintain the frequency/voltage regulation and real/reactive power sharing among multiple BICs under both single and multiple node attacks. The suitability of the proposed method is supported by the stability analysis using Lyapunov methods. Efficacy of the proposed method is demonstrated by the controller hardware-in-the-loop (CHIL) experiment. An ac/dc NMG with four BICs is developed in the OPAL-RT-based real-time simulator. The cyber-resilient controllers are implemented on four commercial programmable logic controllers by B&R automation. The CHIL-based experimental results support the effectiveness of the proposed controller under various attack scenarios.