Research on voltage distributions characteristics in 800 kV GIS under oscillating lightning impulse

GIS (Gas insulated Switchgear) equipment fault has been a major threat to the security and stability of power grid, the safe and reliable operation of GS, is essential to ensure the security and stability of the whole power system. The field oscillating impulse withstand voltage test is an important means to assess the insulation state of GIS. The voltage distribution on the nodes inside GIS under oscillating impulse is helpful for the test result analysis. In this paper, the voltage distribution and wave propagation characteristics in 800 kV extra-high voltage GIS under oscillating impulse voltage are calculated using the numerical simulation software ATP-EMTP based on a 750 kV substation, considered the voltage waveform and peak changes of all observation points under different loads, analyzed the effect of oscillating impulse propagation distance on waveform, how to offset the effect of load change on waveform by adjusting impulse voltage generator parameters. This study would provide data support for the choice of field test scheme and insulation evaluation of extra-high voltage GIS.