고무차륜시스템에서의 3궤조 전차선로의 절연과 부극전압과의 영향 분석

초록

We have analyzed influence of potential rise in negative bus, which caused by decrease of contact wire insulation, upon protecting method of DC ground protection device which detecting potential rise between negative bus and ground in order to detect ground fault in the rubber wheel system. For this analysis, we examined requirement and durability of negative bus on rubber wheel system, and especially suggested potential rise requirement of negative bus which caused by decrease of contact wire insulation. In order to analyze correlation between contact wire insulation and potential rise in negative bus, we modelled rubber wheel system in Korea and simulated potential rise in negative bus according to contact wire insulation resistance change. From the simulation result, we found that potential rise in negative bus increases up to electrical potential level which is able to cause DC ground protection fault when insulation resistance is decreased under 1MΩ. Also we found that potential rise of negative bus can be suppressed by insulting low resistance parallel resistance between negative bus and grounding in order to prevent malfunction from decrease of contact wire insulation.