Apply PMU data for Zone-2 setting of series compensated line

Abstract

Transmission lines protected by distance relays find limitations in the presence of series compensation. The impedance seen by the distance relay is modulated when the fault loop includes the series capacitor. The level of compensation at any instant depends on the number of capacitors connected at that time and at times the bank of capacitors may be bypassed leading to uncompensated line situation. Therefore for correct operation of the distance relay the information on the level of compensation present in the transmission line is essential. In the proposed work the PMU data of both the ends of the line are applied to calculate the level of compensation by which accurate adaptive zone-2 setting of the relay is achieved. The proposed method is tested for a 400/kV system simulated in EMTDC/PSCAD and the results show the high accuracy of the proposed method.