Combined operation of the unified power quality conditioner with SFCL and SMES

This paper evaluates combined operation of the unified power quality conditioner (UPQC) with superconducting fault current limiter (SFCL) and superconducting magnetic energy storage (SMES). The proposed scheme can compensate both voltage sag and current harmonics at the point of common coupling (PCC) on power distribution systems. The results show that the SFCL can reduce the Volt-Ampere rating of the UPQC by limiting the excessive current in the event of a fault. Due to the limited fault current with SFCL, less energy is released from SMES. The combination of electrical and thermal model of a resistive type high temperature superconducting (HTS)-FCL is explained. SMES is a good source due to the high response time of charge and discharge. The operation of the proposed system is verified through simulations with PSCAD/EMTDC.