Parameters Stability Region Analysis of Diesel Generation Forming Hybrid Islanded Microgrid with High Penetration of Renewable Energy

Hybrid islanded microgrids with diesel generators (DGEs) and renewable energy systems have wide applications in remote areas and islands where no electricity can be accessed. Compared with grid-tied microgrids, a more complex impedance interaction feature caused by the randomness and fluctuation of renewable energy sources (RES) and loads brings about a greater challenge on the analysis of small-signal stability for HIMG. In this paper, the impedance aggregation model of the HIMG is derived to analyze the parameter stability region of the HIMG, and the equivalent damping ratio is extracted to investigate the main factors that affect HIMG’s stability. Based on the impedance aggregation model and the equivalent damping ratio, the parameters stability region for the typical operation scenarios is obtained. The HIMG simulation model with multiple DGEs, multiple photovoltaic inverters, and constant power loads is modeled in the PSCAD to validate the parameters stability region by the proposed theoretical analysis method, which can be used as the guidance for the selection of the equipment parameters and the formulation for the operation strategy of HIMG.