The research of 110kV transmission line expanding diameter insulation jacket

To eliminate local corona and reduce minimal discharge distance of transmission lines, this paper analyzed expanding diameter insulation jacket for 110kV transmission line. The minimal discharge distance and its relationship with the diameter of semi-conducting and expanding diameter was calculated theoretically, finding the best size of expanding diameter and general standard of expanding diameter jacket. Then a model of 110kV bare conductor installing expanding diameter insulation jacket is built, to figure out its electric field distribution by finite element method. Through analyzing, expanding diameter insulation jacket proved to be effective, and its minimal discharge distance decreases 60%.