누설전류의 화재 위험성에 관한 연구 = Study on the fire risk of leakage current

다국어 초록 (Multilingual Abstract)

This study aimed to identify the fire hazards of leakage current and stray current that can occur during construction and welding operations and to experimentally analyze their ignition mechanisms. Actual fire cases were analyzed to identify leakage current flow paths and grounding system problems. A scaled-down model was then constructed to analyze the ignition potential, ignition point, and ignition mode. This experimentally verified the occurrence of arc generation, heat generation, metal melting, and ignition in response to voltage changes. Using a DC arc welder, the distribution of stray current and temperature changes were also measured based on welding current flow, grounding clamp attachment location, and contact failure.
The experimental results revealed that during leakage, a strong arc occurred in areas with high grounding resistance or imperfect contact, causing molten material to scatter and ignite nearby combustibles. Furthermore, welding experiments demonstrated that stray currents were generated depending on the position and connection of the grounding clamp, which in turn increased the temperature of the grounding wire and ignited the insulating tape, demonstrating that abnormal current flow was a direct cause of fire. These research results demonstrate that fires caused by leakage current and stray current are not simply electrical anomalies, but rather the result of a complex interplay of factors such as current path instability, grounding resistance imbalance, and potential differences between structures.