Analysis of Technical Standards for Current Collection Performance Verification in Underground Sections

As the construction of underground railways for 180 km/h-class metropolitan express trains increases in Korea, ensuring stable current collection performance in tunnels becomes essential. In tunnel sections, the reduced separation between the pantograph and the overhead contact line (OCL) increases the risk of arc occurrences and affects pantograph dynamics. This study analyzes technical standards for verifying current collection performance between the pantograph and the OCL in underground sections at speeds up to 180 km/h. It was found that conventional video monitoring at 30 fps cannot detect arcs of 5 ms duration at 170 km/h because the train moves about 47 mm during a 1 ms exposure. Detecting such arcs requires a camera with 400 fps or higher. Additionally, with a camera resolution of 1936 × 1216 pixels and a viewing area of 1200 × 800 mm, the minimum detectable defect size is approximately 0.62 mm horizontally and 0.66 mm vertically. The proposed methods improve current collection performance verification, contributing to safer and more efficient underground railway operations.