A novel scheme for distance protection of series compensated transmission lines with TCSC using artificial neural networks

This paper proposes a novel scheme to improve distance protection of compensated transmission lines with Thyristor Controlled Series Capasitor (TCSC). The method uses the type of dynamic feed-forward neural networks called Time Delayed Neural Network (TDNN) to estimate instantaneous values of the voltage across TCSC and then compensates it from the relay voltage signal to mitigate its effects on the measured impedance by distance relays. This technique is simple and accurate and requires only local current at the relay bus. Extensive testing in detail using MATLAB demonstrate that this method is well suited for implementating in a distance relay to improve the reach measurement accurately and effectively.