Calculation and experiments analysis of switching overvoltage in coaxial underground cable distribution network

Bergeron model equivalent circuit of coaxial underground cable network is taken to the switching overvoltage calculation of a real electrical system, the factors of overvoltage are analyzed and explained physically. The results illuminate that the overvoltage may be high enough to threaten the insulation between phases, which strongly proves the phenomena of overvoltage in the power system. The overvoltage is related to the energy stored in system when operating switch, changes as sinusoid with phase angle, falls when the length of the operated cable increases, and rises when the length of the running cable decreases