Evaluation of Breakdown Characteristics of N_2 Gas and CO_2 Gas for Non-standard Lightning Impulse Waveforms

摘要

As potential alternatives to SF_6 gas, the authors are focusing on CO_2 and N_2 gases. In order to apply these gases to actual GIS, the insulation characteristics for overvoltage waveforms generated in an actual field must be obtained. In this paper, with single-frequency oscillations as typical examples of non-standard-LIWs, the insulation characteristics for the these gas gaps were experimentally obtained while changing the frequency and damping rate. Consequently, even if the frequency and damping rate were changed, the dielectric breakdown voltage varied little, consistently remaining higher than that with standard-LIW at a level of 1.03 to 1.24 times.