Tum-to- Tum Fault Detection in Indirect Symmetrical PST Based on Negative Sequence Current Components

Abstract

This paper proposes an algorithm for the protection of Indirect Symmetrical Phase Shift Transformer (ISPST) during minor internal turn-to-turn fault conditions. The proposed algorithm is amalgamation of negative sequence component of current and Phase Angle Shift (PAS). The proposed protection algorithm is able to detect all the internal faults occurred in both the units (series unit and excitation unit) of an ISPST. The algorithm is also evaluated to detect minor Turn-to-Turn (TT) internal fault of 1% shorted winding. In addition to that effect of CT saturation during external fault has also been considered. The simulation of different fault conditions in an ISPST has been performed using PSCAD/EMTDC platform. © 2018 IEEE.