Localização de faltas em linhas de transmissão baseada no espectro de ondas viajantes.

Abstract

This work aims to study the phenomenon of traveling waves in transmission lines and its application for fault location. For this, a bibliographic review was made and one of the methods proposed in the literature was selected to identify failures in transmission lines to be further investigated, which is based on the dominant frequency of the voltage signal in the line, after opening the circuit breakers. A modeling of an electrical system based on real data composed of two bars was made, without ATP software (Alternative Transients Program), so that it is possible to observe the spectra of traveling waves after the occurrence of a fault and the protection action. An algorithm is provided in the system so that the dominant frequency of these residual waves is collected and, from it, the exact location when a fault has occurred is estimated. The following types of faults in the electrical system will be distributed: phase-toground, phase-to-phase, phase-to-earth and three-phase. For each type of failure, a sensitivity study and parametric analysis were carried out with evaluation of the method with better precision, in addition to a study aimed at improvements in the method in view of the difficulties encountered. The method was able to be applied with a very low error rate for all types of faults. It was shown to be more efficient in faults that occur from 25 km from the local terminal and with fault impedances between 1 and 10 ohms. For impedances from 50 ohms, the method has limitations in its performance.