Effect of TCSR on Measured Impedance by Distance Protection in Presence Single Phase to Earth Fault

This paper presents the impact study of apparent reactance injected by series Flexible AC Transmission System (FACTS) i.e. Thyristor Controlled Series Reactor (TCSR) on the measured impedance of a 400 kV single electrical transmission line in the presence of phase to earth fault with fault resistance. The study deals with an electrical transmission line of Eastern Algerian transmission networks at Group Sonelgaz (Algerian Company of Electrical and Gas) compensated by TCSR connected at midpoint of the line. This compensator used to inject active and reactive powers is controlled by three TCSR’s. The simulations results investigate the impacts of the TCSR on the parameters of short circuit calculation and parameters of measured impedance by distance relay in the presence of earth fault for three cases study. Keywords—TCSR, Transmission line, Apparent reactance, Earth fault, Symmetrical components, Distance protection, Measured impedance.