Fault location in series capacitor compensated three-terminal transmission lines based on the analysis of voltage and current phasor equations and asynchronous data transfer

Abstract

In this study, a new algorithm for fault location in series capacitor compensated three-terminal transmission lines using the distributed line model is proposed. The proposed algorithm uses the sampled data of currents and voltages of all the three terminals, which are transferred asynchronously using telecommunication lines. All data transmission delays are calculated in terms of line parameters as well as the measured values of currents and voltages of the three terminals. Based on the data received from the three terminals, current and voltage equations of different points of the network are constituted for different types of faults. By solving these equations according to their boundary conditions, accurate locations of faults are estimated. One of the salient features of the suggested algorithm is that the schemed equations are independent of the model of the series capacitor compensator during fault occurrence and its protective circuitry. Also, based on the sensitivity analyses performed in this paper, the presented algorithm works perfectly against the errors caused by measurements and parameters. The test system and the suggested algorithm were realized in MATLAB environment. The obtained simulation results for different fault types occurring in various places in the line verify the accurate performance of the algorithm.