Directional Relaying During Secondary Arc Using Negative-Sequence Superimposed Technique

The presence of secondary arc during single-pole tripping (SPT) poses a challenge for protection schemes. A conventional directional relaying algorithm based on the negative-sequence component is affected due to the presence of nonfundamental frequency components in voltage and current signals during secondary arc. In this paper, a negative-sequence-based superimposed technique is proposed to provide a solution to directional relaying during the SPT condition which is not affected by the presence of a secondary arc. The technique is independent of coupling capacitor voltage transformer location and not affected by high fault resistance.