Development of current dynamic estimator for Islanding Detection of inverter based Distributed Generation

Various Islanding Detection Methods (IDMs) have been developed within the last ten years due the tremendous increase in the penetration of Distributed Generation (DG) in distribution system. This paper proposes a new resident passive IDM in which a dynamic estimator is designed based on the system dynamics during islanding occurrence. The dynamic estimator estimates the amplitude of the current injected by the grid at the point of common coupling with the DG. The estimator can also determine the flow direction of grid current. The main goal of this paper is to provide transient analysis for the islanding detection problem and to approximate the Non-Detection Zone (NDZ) of the new passive IDM. Moreover, estimator sensitivity to grid amplitude, frequency and angle variations and disturbances will be studied and simulated.