Development of 22.9 kV high-temperature superconducting cable for KEPCO

Abstract Superconducting cable is expected to be one of the most economical ways to improve both the stability and capacity of electrical transmission and distribution lines, so several studies of high-temperature superconducting (HTS) cable have been initiated around the world. SEI was recently engaged by the Korea Electric Power Corporation (KEPCO) to install a 22.9 kV–1250 A HTS cable system, comprising a 100 m HTS cable, two terminations and a cooling system, all manufactured in Japan and shipped to the KEPCO Gochang test site in Cheolabuk-Do, ROK (Republic of Korea). After system installation and assembly, the cable was cooled with liquid nitrogen. Following several checks, including measurements of critical current and heat loss, and AC voltage and current tests, a commissioning test saw the cable carry 1250 A at 22.9 kV for 48 h, meeting all requirements. This report outlines the KEPCO HTS cable project, including system design, manufacture, installation and testing.