New Ground Fault location Algorithm for Transmission Line Using Synchrophasors

This paper presents a new algorithm for fault detection, classification and location which compensate for phase angle error due to line charging current using synchronised phasor measurements in SMART GRID. The paper includes fault detection with combination of phase and sequence components by using ground distance relay expression in terms of sending and receiving end voltages and currents. Here equations are arranged in terms of two unknowns i.e. fault distance and fault resistance with the separation of real and imaginary parts by assuming fault distance as strictly resistive and constant during analysis period. Solution of matrix estimates fault resistance which further compensated to obtain fault distance. Synchronised measurements received from two ends terminals of transmission line are incorporated with equivalent-π model of transmission line. Extensive simulations studies show that the proposed scheme provides accurate fault location under various system and fault conditions. Also proposed algorithm is highly encouraging with ground faults. Simulations results show that the fault estimation is accurate for low resistance faults.