DEVELOPMENT AND TEST-RESULTS OF A DOUBLE 0.5MJ COIL SMES SYSTEM

The design and test results of a SMES system built for Korea Electrica l Power Company are described. scribed. The system consists mainly of two superconducting (sc) coils, two cryostats, primary power supply an d DC-AC-DC converter to transfer the stored energy from one coil to an other and vice versa. Each of two almost identical coils can store mor e than 0.5 MJ at about 1.55 kA. Minimum energy transfer time is about 2 s. The conductor is made by cabling of several sc, copper and stainl ess steel strands around a copper core. At 2 s transfer time mode, the AC losses ill each coil are about 500 J. The cryostats are manufactur ed mainly of thin-walled stainless steel. Their eddy current losses at liquid helium temperatures are lower than AC louses in the coils. Aft er preliminary testings in Moscow the system was delivered to Republic of Korea and successfully tested at Korea Electrotechnology Research Institute.