Transient Stability Analysis of an Islanded Microgrid under Variable Load

Abstract

In this paper, we investigate some aspects related to microgrid (MG) stability. Due to different applications of MG, its structure and deployment topology vary depending upon the nature of application and operating modes (islanded or grid connected). So, the stability of MGs varies accordingly. This paper precisely explains the stability aspects (e.g., phase angle and power losses) of remotely located islanded MG having the capability to integrate distributed energy sources. Initially, the stability of three bus system is assessed under variable load and find some gaps related to stability as MG involves a high penetration of distributed energy sources. These gaps indicate that stability of a MG is not only in the control of generation/load but also in its coordination with other loads. After that, we implement the load coordination technique and analyze the stability against fixed and dynamic loads. For comprehensive analysis, four different cases are considered in which we vary load at different bus bars and check the performance. Lastly, we integrate the distributed energy source to islanded MG and perform the stability analysis. For validation purpose, extensive simulations of the proposed cases are conducted using Matlab. Simulation results depict that load coordination technique is more efficient regarding MG stability.