Distributed Event-Triggered Secondary Control for Average Bus Voltage Regulation and Proportional Load Sharing of DC Microgrid

This paper proposes a novel distributed event-triggered secondary control method to overcome the drawbacks of primary control for DC microgrids. With event-triggered distributed communication, the proposed control method can achieve system-wide control of parallel operating DGs with two main control objectives: a) estimate the average bus voltage and regulate it at the nominal value; b) achieve accurate current sharing among the DGs in proportion to their power output ratings. Furthermore, the proposed control strategy can be implemented in a distributed way that sharing the required tasks between the DGs. Thus, it shows the advantages of flexible and scalable. Furthermore, this paper also proposes a simple event-triggered condition that does not need extra state estimator. Thus, limited communication among neighbors is required only when the event-triggered condition is satisfied, which significantly reduce communication burden in the cyber layer.