ESS 절연성능 향상을 위한 절연배리어 AC 절연파괴특성 분석

Abstract

The importance of ESS (Energy Storage System) protection system is increasing due to the recent ESS fire events. It is necessary to achieve the insulation performance for AC voltage components caused by faults during operation. In this study, AC electrical reakdown(BD) voltage was analyzed varying with the insulation barrier design factors to improve the insulation safety of ESS. First of all, the correlation between the air breakdown path and AC breakdown voltage was experimentally investigated owing to the insulation barrier shape. Moreover, the effects of dielectric constant and the thickness on insulation performance were examined. Finally, the equivalence between the air breakdown propagation distance and the air gap distance was compared, and the design criteria for the insulation barrier was presented. Through the results, it was found that AC breakdown voltage increased with the air breakdown propagation distance. Moreover, AC breakdown was not influenced by the thickness but by the barrier material properties. It was verified that AC breakdown voltage could be estimated, based on the average breakdown propagation field and the air breakdown propagaion distance.