Study of Surface Electric Field Distribution and Calculation Method of Corona Inception Field Strength of Low-Wind-Pressure Conductor

In order to reduce the severe impact of high winds on the safe operation of overhead transmission lines, low-wind-pressure conductors are increasingly used in power transmission and transformation projects. As the surface shape or roughness of the low-wind-pressure conductor changes, its corona characteristics will also change accordingly. Therefore, it is necessary to study the surface electric field distribution and the calculation method of the corona inception field strength of the low-wind-pressure conductor. This paper first uses the finite element method to analyze the DJL/LB1A-630/45 type low-wind-pressure aluminum clad steel reinforced aluminum stranded conductor and the JL/LB1A-630/45 type aluminum clad steel reinforced aluminum stranded conductor under different voltage levels and different split numbers. Then, starting from the basic physical process of corona discharge, based on self-sustained discharge, the calculation criterion of the corona inception field strength of the conductor is established. Finally, based on this criterion, this paper calculates the corona inception field strength of the low-wind-pressure conductor and round stranded conductor, and explores the law of the corona inception field strength with the atmosphere pressure.