Operation and Maintenance of the HVDC Submarine Cable Between Mainland and Jeju Island

High Voltage Direct Current (HVDC) systems serve as crucial components in modern power transmission networks, offering numerous advantages over traditional AC systems. This paper explores the operation and maintenance of HVDC submarine cables as well as its reliability enhancement strategies of the cable between the mainland and Jeju Island, Korea. It outlines current protection measures for submarine cables and details the operation and management methods employed by the Korea Electric Power Corporation (KEPCO). Furthermore, it discusses ongoing efforts to enhance operational reliability, including real-time fault detection systems and the development of a submarine cable monitoring system utilizing optical sensing techniques.