Design of hv transmission lines to combat insulator pollution problems in the eastern region of Saudi Arabia

Insulator contamination has been identified as the most limiting design parameter of external insulation of high voltage transmission lines in the eastern region of Saudi Arabia. Saudi Consolidated Electric Company of the Eastern Region (SCECO East) has made several attempts to combat the problem by increasing insulation level, changing insulators, and using nonceramic insulators. The company, however, still relies heavily on an expensive hot-line washing. Only, through a systematic research, it can be possible to identify the most reasonable compromise between the insulation level, insulator design, and frequency of washing. in an attempt to understand the severity of prevailing pollution in the eastern region, two insulator research stations were erected. The first energized test station located at Ghazlan, a typical representation of a coastal environment, was commissioned in April 1985. Located 500 m from the Arabian Gulf, the site is 1 km away from Ghazlan Power Plant and around 15 km from the industrial city of Jubail. The other test station, located on the campus of King Fahd University of Petroleum and Minerals, is about 7 km from the Arabian Gulf with the nearest highway only 500 m away. It was commissioned in October 1985. At these test stations, a large amount of pollution severity data of different insulators have been acquired through monthly ESDD measurements. These data are analyzed using a newly developed severity-duration technique to determine the design pollution levels for the investigated sites. Through an extensive laboratory research program, electrical performance of representative insulators was studied over a wide range of pollution severity. Through a careful integration of the field and laboratory data, potentially suitable insulators have been identified and necessary insulation design requirements of high voltage transmission lines are recommended for the investigated sites of the eastern region of Saudi Arabia.