Identification of faulted section in TCSC transmission line based on DC component measurement

This paper presents an analysis of possibility of detection of a fault position with respect to the compensating bank in a series compensating transmission line. The algorithm designed for this purpose is based on determining the contents of dc components in the distance relay input currents. Fuzzy logic technique is applied for making the decision whether a fault is in front of the compensating bank or behind it. The delivered algorithm has been tested and evaluated with use of the fault data obtained from versatile ATP-EMTP simulations of faults in the test power network containing the 400 kV, 300 km transmission line, compensated with the aid of TCSC (Thyristor Controlled Series Capacitor) bank installed at mid-line. The results of the evaluation are reported and discussed.