Overvoltage Study on UHV AC Half Wave Length Transmission System

Abstract

In China some resource bases in the west are located at a distance of about 2800~3000km from the load centers in the east. AC Half Wave Length transmission in UHV stage is an alternate for the long distance and large capacity power transmission. A study model of half wave length line transmission system was established. The power frequency overvoltage, switching overvoltage and grounding fault overvoltage were studied using EMTP. The study result shows that the highest overvoltage occurs during grounding faults. The amplitude and waveform of overvoltage during grounding fault are affected by fault type, fault location as well as the characteristic of the protection system. The use of metal oxide arresters to limit overvoltage is discussed. The parameters and configuration of metal oxide arresters is suggested.