A novel method for detection of covered conductor faults in medium voltage overhead line systems

Abstract

Although there aremany reasons whymedium voltage (MV) overhead lines with covered conductors (CCs) are used instead of aluminum-conductor steel-reinforced cables, the operation of CCs takes into account a difficult detection of faults, e.g., the contact of a tree branch with a CC. In this paper, we continue with the previous work on an electric voltage-based method enabling the detection of the CC faults; we introduce a new indicator of the faults based on the frequency of peaks in the signal of partial discharges. We mainly demonstrate the fault detection in a real MV distribution system, including a number of fault detectors; a fault is detected in 99.2% of occurrences within a long-term testing, although the cost of the detector is minimized in comparison with other similar fault detectors.