Discrimination between in-zone and out-of-zone faults during power swing condition using synchrophasor data

Abstract

A new algorithm to discriminate between in-zone fault and out-of-zone fault conditions under power swing condition for wind/synchronous generators (WG/SG) integrated power transmission network is presented in this paper. The proposed algorithm is based on the calculation of a transmission line positive sequence power loss index, derived by calculating the absolute difference between the calculated and measured values of positive sequence real power loss. The authenticity of the proposed technique is verified by performing Hardware-in-Loop (HIL) simulation in the Real-Time Digital Simulator (RTDS) framework along with physical Phasor Measurement Units (PMUs), Phasor Data Concentrator (PDC), Global Positioning System (GPS) clock, and voltage and current amplifiers. Various events such as power swing, in-zone (including close-in and high resistance) faults during power swing and out-of-zone faults during power swing are simulated by modeling WG/SG integrated IEEE-9 bus system in RSCAD (Real-Time Simulator Computer-Aided Design) framework. The single pole tripping, impact of noise and CT saturation on the proposed algorithm is also analyzed. The proposed algorithm offers accurate discernment between in-zone and out-of-zone faults during power swing conditions. The results obtained reveal increased sensitivity and improved distinguishing capability of the proposed algorithm in contrast to those of many other approaches proposed in the literature.