An Improved Active Islanding Detection Technique for Multi-Inverter Power System

Due to the increased penetration of multi-inverter distributed generation systems (DGs), different DGs technologies, inverter control methods, and other inverter functions are challenging the capabilities of islanding detection. In addition, multi-inverter networks connecting the distribution system point of common coupling (PCC) create islanding at paralleling inverters, which adds on to the vulnerability of islanding detection. Furthermore, available islanding detection must overcome more challenges from non-detection zones (NDZs) under reduced power mismatches. Therefore, in this study, a new method called parameter self-adapting active islanding detection was utilized to minimize the dilution effect and reduce the non-detecting zones in multi-inverter power systems. The method utilizes an active frequency drift (AFD) method and applies a positive feedback gain of parameter adaptive, which significantly minimizes the NDZs at parallel inverters. The simulation and experimental outcomes indicate that the proposed method can effectively weaken the dilution effect in multi-inverter networks connecting the distribution system PCC.