A Study on Smart Power Quality Improvement Device Application in the Gyeongwon Line Railway System

Following the opening of the Gyeongwon Line section between Dongducheon and Yeoncheon, a total of six power outages occurred due to failures of surge arresters installed on the overhead catenary system. On-train testing and analysis identified excessive leakage current and harmonic distortion as the primary causes. As an interim measure, an RC-Bank was installed at the Yeoncheon SSP, and the main transformer at Uijeongbu SS was operated in parallel to mitigate the leakage current. Subsequently a Smart Power Quality Improvement Device (SPQ) was deployed and its performance was verified under single transformer operation through live testing. The results demonstrated significant voltage stabilization and harmonic suppression. This study presents a practical case of SPQ application for improving power quality in railway power supply systems.