A novel approach to the distance protection, fault location and arcing faults recognition

In this paper a novel two-stage numerical algorithm devoted to fault distance calculation and arcing faults recognition is presented. The first algorithm stage serves for the fault distance calculation. Fault distance is calculated from the fundamental frequency phase voltages and currents phasors, utilizing the positive-and zero-sequence impedance of the line as an input parameter. The second algorithm stage serves for the arc voltage amplitude calculation. It utilizes the fault distance obtained from the first algorithm stage and the third harmonics of the terminal phase voltages and line currents phasors as input parameters. From the calculated value of arc voltage amplitude it can be concluded if the fault is transient arcing fault or permanent arcless fault. The phasors needed for algorithm development are calculated by using the discrete Fourier technique. In the paper the solution for the most frequent phase-to-ground faults is given. The results of algorithm testing through computer simulation and processing of real field data records are given.