Phaselet Approach for Islanding Detection in Active Distribution Networks

A novel moving window phaselet based approach has been proposed in this paper for quick islanding detection (within 5-10ms) in ADNs, even in the case of zero power mismatch/ power balance case. The Instantaneous Phase Angle (IPA) and magnitude of the PCC voltage have been extracted through a linearly moving window phaselet to generate two indices - Phaselet Angle Difference (PAD) and Phaselet Magnitude Difference (PMD) at sub-cycle rate, which are critical parameters in quickly discriminating islanding from non-islanding events in ADNs. These indices also offer the added advantage of quickly classifying the type of fault, in the events of faults in ADN. Real Time Digital Simulator (RTDS) based results prove the efficacy of the proposed phaselet based technique in accurately and dynamically estimating the phasors within sub-cycle interval and quickly detecting islanding, even in power balance case with different load quality factors as per standard.