Characterization of Insulator Faults in the Dhofar Power Transmission Network

In power transmission systems, polymer composite insulators are widely used to provide electrical insulation. The safe operation of a power system relies heavily on the detection and replacement of defective insulators on power transmission lines. Most transmission line companies detect faulty insulators by measuring the voltage across them, performing thermal inspections or by examining insulator cracks. However, as transmission lines are long, identifying degraded insulators may be difficult. This paper examines reports of previous incidents that are related to insulator faults or flashovers in the Dhofar transmission network. This network is located in the southern part of the Sultanate of Oman. It extends to coastal areas, an industrial area, desert environment, and a mountainous terrain. Based on collected incident reports, it is evident that the majority of insulation faults are due to factors that are specific to the area where the transmission lines were installed. These factors include low atmospheric pressure, high humidity, salt deposits, temperature, wind, high levels of pollution and bird activity combined with insulator accelerated degradation. As part of this study, different areas and related factors are examined in order to be able to understand future insulator faults on the Dhofar transmission network.