Enhanced Islanding Detection Using a Positive Sequence Impedance Angle in an Active Distribution System

Islanding detection has become a serious concern due to the extensive integration of renewable energy sources with the main grid. This article addresses two significant challenges with islanding detection schemes: the non-detection zone (NDZ) and system-specific applicability. The purpose of this work is to provide an islanding detection technique that operates at zero NDZ and is adaptable to all types of renewable energy sources. This research focused on the passive islanding detection technique (IDT), which is simple to implement, inexpensive, and effective. This paper presented a novel passive islanding scheme to detect islanding events in an active distribution system based on the rate of change of the superimposed positive sequence impedance angle (ROCOSPSIA). The IEEE 13 bus test system is simulated in the MATLAB/Simulink environment. The proposed scheme detects islanding within 9 ms when the generated power and load power are equal. It is also robust and does not require NDZ. The proposed scheme successfully differentiates between islanding and non-islanding events, which helps to prevent avoidable DG malfunctions. The performance of the proposed scheme has been tested in several test systems, which is better than some conventional techniques.