Admittance Modeling and Stability Analysis of Droop Inverters-Based Island Micro-Grid

Abstract

This paper presents a precise admittance modeling and stability analysis method for inverters-based island micro-grid. Due to the characteristics of inverters-based island AC distribution system, it is prone to be unstable. In order to study the root of system instability, a precise output converter admittance model is established. Based on the admittance model, the stability of micro-grid system has been analyzed. At the same time, a stabilizing control method is proposed to expand the stability range of the system. Finally, simulation results verify the accuracy of admittance model and stability judgement in island AC system, and verify the effectiveness of the stabilizing control method.