The insulation performance analysis of UHV DC bushing under temperature

Abstract

Under the influence of high voltage, UHV DC bushing will appears another complicated problem, which is the thermal insulation of the bushing. This paper has calculated the temperature distribution of the long term stable operation of the DC bushing under rated current. The gradient distribution of high voltage DC bushing in the radial temperature is obtained from the inside to the outside; The temperature present lowly in the end and highly in the middle which is in the axial direction, the maximum temperature appears near the top of conductive epoxy rods. And when the temperature of the insulation medium increases, it will seriously affect the resistivity value, which affect the bushing electric field distribution, and cause the insulation problem.