Fault Location for Series Compensated Lines Eliminating Parameters as a Setting

Abstract

Unlike protection applications, precise fault locator requires accurate line parameters which are not constant over the time as a result of aging and environmental impact on conductors. Traditional fault location approaches for series compensated lines are dependent on the prior knowledge of line electrical parameters, percentage and type of compensation. However, non linear characteristics of Metal Oxide Varistor (MOV) during fault makes the task of fault location more complex. In order to address these, a setting free fault location methodology for series compensated lines using synchronized data is proposed which is independent of MOV characteristics. The fault location algorithm is phasor-based and parameters are estimated using Dommel’s time domain equations. Estimation of parameters requires computation of propagation constant which is obtained using first two travelling wave peak arrival times of arial mode component of both end fault currents. Wavelet transform technique is used to extract the travelling waves. The proposed method is independent of the percentage, type, location of the compensation and MOV characteristics. The proposed method is verified using data simulated in PSCAD/EMTDC tools. The proposed method is tested for different fault scenarios and performance is found to be accurate.