Resilient Discrete-Time Quantization Communication for Distributed Secondary Control of AC Microgrids Under DoS Attacks

For islanded ac microgrids with constrained digital communication networks under denial-of-service (DoS) attacks, this article proposes a resilient distributed secondary control strategy with a discrete-time quantization communication scheme to enhance the resilience to DoS attacks and to reduce communication loads. To cope with the time-constrained DoS attacks, the proposed discrete-time communication scheme combines a periodic communication attempt in the time intervals in presence of DoS attacks, and an event-triggered communication in the time intervals in absence of DoS attacks. Moreover, a dynamic quantization scheme for data transmission is introduced in the distributed control for the stability of the frequency and voltage at the reference. Then, a sufficient stability condition is established for the microgrid and the tradeoff between the communication attempt period and DoS attacks is obtained. Simulations of a microgrid are presented to verify the proposed resilient secondary control strategy.