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

The superconducting fault current limiter (SFCL) for a nominal voltage of 220 kV and a rated current of 1200 A was developed by SuperOx company to be applied in high voltage substation in Moscow, Russia. The device is a three-phase dead-tank apparatus and is equipped with a closed-cycle cryocooling system. 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 accordance with the IEEE C37.302-2015 test guide and Russian national standards for high voltage electrical equipment. The installation 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.