Numerical Algorithm for Adaptive Autoreclosure and Fault Distance Calculation

This paper presents development and testing of a new numerical spectral domain algorithm devoted to blocking unsuccessful automatic reclosing onto permanent faults and the fault distance calculation. The arc voltage amplitude and the fault distance are calculated from the fundamental and third harmonics of the terminal voltages and currents phasors. From the calculated arc voltage amplitude it can be concluded if the fault is transient arcing fault or permanent arcless fault. If the fault is permanent automatic reclosure should be blocked. The algorithm can be applied for adaptive autoreclosure, distance protection, and fault location. The results of algorithm testing through computer simulation are given.