Discrete-Time Self-Triggered Control of DC Microgrids with Data Dropouts and Communication Delays

In this paper, a novel discrete-time self-triggered (DTST) distributed controller is developed for DC microgrids with data dropouts and communication delays. To meet the discrete-time (DT) nature of digital systems, a DT distributed controller is first proposed to achieve load current sharing and average voltage regulation simultaneously in DC microgrids. To further relax the communication restrictions, a novel self-triggered mechanism is developed and integrated along with the DT controller, where the local controller proactively estimates the next communication instant ahead of time. Since the controller can only be triggered at DT instants, the Zeno phenomenon is avoided. Moreover, an algorithm is further proposed to compensate for the effect of data dropouts and communication delays. Through Lyapunov synthesis, stability and convergence of the closed-loop system with the proposed design is guaranteed. Finally, detailed simulation studies validate the effectiveness of the proposed DTST controller under communication imperfections.