Bifurcation analysis of the islanded micro‐grid with constant power loads

Abstract

Most of the distributed energy resources (DERs) are connected to the micro‐grid through the power electronic inverter. Due to the limited inertial and capacity of the inverter‐based DERs, the micro‐grid in islanded mode is susceptible to the non‐linear instability such as oscillation. In this study, the authors analyse the non‐linear behaviour of an islanded micro‐grid with constant power load by the bifurcation theory. At first, the proposed micro‐grid is developed on the dq reference frame. Then, the numerical bifurcation technique is used to detect the bifurcation point when parameters change. Considering the current limitation of the DERs, the non‐linear instability of the micro‐grid caused by the current saturation is also investigated. Simulation validates the detected bifurcation phenomena of the proposed micro‐grid.