The performance evaluation of distance protection for transmission lines possessing TCSC

In this paper, a Thyristor Controlled Series Capacitor (TCSC) is studied and simulated by using EMTDC/PSCAD software. Different fault cases are generated by placing the TCSC at the middle of the transmission line of a two source equivalent power system. The fault data are used for evaluating the performance of the distance relay placed at one end of the line. The findings are reported in this paper for few representative test cases. The observations clearly show that by using only conventional distance relaying based protection scheme reliable protection for TCSC based transmission line cannot be achieved. Thus, additional algorithms are required which can support conventional distance relaying for protecting such transmission systems.