A positive sequence directional relaying algorithm for series compensated line

Summary form only given. Series capacitor imposes problems to line protection and other online decisions. The directional relaying issues during voltage and current inversions in a series compensated line are addressed in this paper. Conventional directional relaying algorithm uses fault voltage and current phasors to derive the decisions and thus, finds its limitation at voltage or current inversion. The paper proposes a fault direction estimation technique for series compensated line using phase-change in positive sequence current and magnitude-change in positive sequence voltage at fault. The technique is evaluated using data simulated with EMTDC/PSCAD for a series compensated line and the dynamic performance of the algorithm is also studied.