Effects of system configuration on switching overvoltage and insulation strength of high voltage equipment

This paper presents the study of power system configuration effecting on switching overvoltage and insulation strength of high voltage equipment. Various sceneries such as energizing line with and without electrical load, energizing the overhead line with variable length, system with and without power cable and effect of source impedance are considered. The Alternative Transients Program (ATP) with ATPDRAW, graphical pre-processor, is applied to a typical 115 kV sub-transmission system of Metropolitan Electricity Authority (MEA), Thailand. The results will be used to evaluate the insulation strength of high voltage equipment in order to improve system reliability. Hence, to maintain the reliable power system, the impact of switching overvoltage must be effectively reduced and the strength of high voltage equipment must be properly maintained.