First Russian 220 kV Superconducting Fault Current Limiter (SFCL) For Application in City Grid

The superconducting fault current limiter (SFCL) for a nomi-nal voltage of 220 kV and a rated current of 1200 A was devel-oped by SuperOx company to be applied in high voltage substa-tion in Moscow, Russia. The device is a three-phase dead-tank apparatus and is equipped with a closed-cycle cryocooling sys-tem. Liquid nitrogen serves simultaneously as a cooling and an insulating media. The device makes use of about 25 km of 12 mm wide high-performance 2G HTS wire with uniform properties along the length. High-voltage tests of the device were performed at Korea Electrotechnology Research Institute (KERI) in accord-ance with the IEEE C37.302-2015 test guide and Russian nation-al standards for high voltage electrical equipment. The installa-tion of the SFCL at substation in parallel with the existing air core reactors was completed in 2019. Since then, the device is in a daily operation. Over this period, SFCL has fully confirmed its design specifications including transmitting over 80 million kWh to customers and experiencing three fault current events.