A Distributed Event-Triggered Fixed-Time Secondary Control for DC Microgrids Without Continuous Signal Transmission

Abstract

DC microgrids, as an emerging and reliable grid system, are widely applied to accommodate ever-increasing distributed generators (DGs). To achieve the effective orchestration of integrated DGs and satisfy the elevated performance expectations for the overall system, the deployment of an enhanced secondary control strategy with rapid response dynamics while substantially reducing communication requirements is crucial. To accomplish this goal, a distributed event-triggered fixed-time secondary control scheme is proposed to achieve a concurrent dc bus voltage regulation and current sharing among DGs within a fixed time. Moreover, the event-triggered communication mechanism is designed, and each DG only needs to send one latest variable value to its neighbors when the designed event-triggering conditions are fulfilled, contributing to reduced communication. Remarkably, this method can eliminate the need for bus voltage sampling, facilitating a low-cost implementation and enhanced system reliability. The stability of the proposed strategy is rigorously proved, and the avoidance of the Zeno behavior is also certified. Simulation and experimental results are presented to substantiate the efficacy of the proposed strategy.