Electric Energy Exchange and Applications of Superconducting Magnet in an SMES Device

A unified energy exchange system with an equivalent dc circuit topology is presented for superconducting magnetic energy storage (SMES) study. The principle and experimental prototype design have been carried out to study the dynamic energy exchange characteristics of SMES for both voltage sag and swell compensations, with a new bridge-type I/V chopper and relevant digital control method introduced and compared with the conventional chopper. The bridge-type I/V chopper has been demonstrated to be more suitable for low-voltage power applications because of its high energy storage and exchange efficiencies. The integrated SMES application solutions and characteristics in the modern power systems have also been discussed using two sample cases of daily load leveling and voltage fluctuation compensation presented.