An Innovative Islanding Detection Scheme in a Distributed Generation using Phase Angle between Negative sequence Superimposed components of voltage and current

This article presents a unique method for detecting localized islanding in distributed generation (DG) systems connected to the main power grid, using a passive approach. The proposed methodology involves calculating the cumulative sum (CUSUM) of the phase angle between the negative-sequence based superimposed components of current and voltage (SC2) at the distributed generation (DG) side, which is then employed to detect the occurrence of islanding. The magnitudes of negative sequence superimposed current and voltage are also computed and the magnitudes are found to be inconsistent. The current active methodologies deliberately introduce disruptions to the power system, posing potential issues concerning stability, power quality, and overall reliability of the prevailing grid. Passive methods, on the other hand, has a considerable non-detection zone (NDZ). The technique recommended in this article successfully addresses the NDZ issue without introducing any disturbances. To evaluate its effectiveness, PSCAD/EMTDC is employed for simulating a system. The proposed method undergoes several tests on the said system to assess its performance. The results demonstrate that the suggested approach exhibits the minimum NDZ and can distinguish islanding within a remarkably short duration of 10 ms, significantly faster than a recloser which typically requires 150 ms for detection.