Distributed direct power sliding-mode control for islanded AC microgrids

Abstract

The aim of this paper is to develop a novel distributed direct power sliding-mode control for an islanded AC microgrid. This solution replaces the droop mechanism of each inverter with two separate sliding surfaces working as primary/secondary controllers. The design of these surfaces is based on the dynamic model of the active and reactive powers to enhance the robustness against line impedance mismatches. Moreover, a theoretical stability analysis is presented. The main features of this proposed control are: first, regulate the voltage and frequency achieving an accurate active and reactive power sharing; second, achieve stability under a wide range of line impedances; and third provide robustness toward external disturbances, including communication failures. Finally, the experimental results verify the controller performance, the stability with different line impedances, and the robustness against communication partitions.