An Active Anti-Islanding Algorithm for Inverter Based Multi-Source DER Systems

Islanding detection is an essential function for safety and reliability in grid connected distributed generation (DG) systems. Several methods for islanding detection are proposed, but most of them are not efficient for multi-source configurations, or they may produce important power quality degradation getting worst with DG penetration increasing. This paper presents an active islanding detection algorithm for voltage source inverter (VSI) based multi-source DG systems. The proposed method is based on voltage positive feedback theory. Simulations by MATLAB/Simulink/SimPowerSystems were used to evaluate its performance and its advantages concerning time response and power quality effects under critical conditions as load´s unity power factor and high quality factor.