A New and Accurate Fault Location Method in Three-Terminal Transmission Lines Compensated by Series-Connected Flexible AC Transmission System Devices

This paper proposes a new method to fault location in the three terminals transmission line compensated with series FACTS Devices. This method is based on the converting three line networks to two line networks after recognizing the faulty section and solving accessing the fault distance. So to solve the problem of fault location before determining distance to faulty section, new method to determine faulty section is proposed and then by converting three line networks to two line networks, the location of fault is determined using the proposed algorithm. In this method distributed transmission line model in time domain has been used which is another advantage of the proposed method compared to previous methods. This method for determining the faulty section used simultaneous voltage and current of all three terminals as input data. Due to problems in the modeling of FACTS devices during fault location, our proposed method does not used modeling series FACTS devices. Our proposed algorithm is not sensitive to the resistance of fault, the fault inception angle and fault type and do not dependent on compensator device location and its parameters. This method is good for all transmission lines compensated with any type of series compensator. Different types of fault in any different distance and situation simulated by using MATLAB/SIMULINK software on compensated three line network with Thyristor Control Series Capacitor(TCSC). The performance of the proposed algorithm is evaluated under different structural and fault conditions. The simulation results confirm the high accuracy of the proposed algorithm.