Effects of Wave Propagation Velocity on Fault Location Approaches in Power Distribution Systems

Abstract

To reduce the frequency and duration of interruptions on the energy supply, electric utilities should adopt efficient fault location approaches. Traveling wave-based methods are a good alternative for fault location, as they are more accurate, faster, and less affected by the fault characteristics than the traditional impedance-based approaches. Basically, the accuracy of traveling wave-based approaches depends on the precise identification of the wavefronts arrival times in the meters, as well as on their traveling wave velocities. However, most of the traveling wave-based approaches adopt a single traveling wave velocity to estimate fault locations, which may affect the accuracy of the estimates since the waves tend to travel at different velocities in conductors with different physical characteristics. This paper investigates the effects of wave propagation velocities on fault location estimates via traveling wave-based approaches. Mathematical morphology is used to identify the arrival time of the traveling waves generated by faults on the meters. Different velocities, calculated based on the electrical parameters of the network conductors, are used to determine the fault location in a real distribution system.