Virtual Resistance Power Sharing Scheme Based on Sliding Mode Control in Islanded Microgrids

Droop control is widely employed for power sharing in islanded microgrids. However, the power sharing accuracy is compromised when feeder parameters between distributed generation units are mismatched. This paper proposes an adaptive virtual resistance scheme implemented using a robust sliding-mode controller (SMC). The modeling uncertainties of the microgrid model are analyzed and a design procedure of the SMC is presented. Local voltage controllers are implemented using finite-set predictive control in order to provide high closed-loop bandwidth and thus decouple voltage and power control loops. Simulation results are discussed to evaluate the effectiveness of the proposed method.