Comparative study on the fastest effective fault limitation for stabilized and stabilizer-free high Tc superconductors

Abstract

The fastest effective fault limitation is one of the selection criterion of high Tc superconductors (HTS) for resistive type fault current limiter (R-SFCLs) application. In the present work, we have given a comparative DC & AC performance study on HTS tapes with and without stabilizer. At first, we have investigated the temperature dependent DC resistivity of the SS stabilized Bi2223 based conductor, Cu (50 µm substrate) and SS (75 µm substrate) stabilized YBCO based coated conductors (CCs) and compared with the stabilizer free YBCO based CC (50 µm and 100 µm substrate). We have studied the DC transport properties (E–I) of the stabilized and stabilizer-free tapes to obtain flux-flow resistance before reaching normal state, critical current and ‘n’ factor at 1 µV/cm criterion. Further, the 1st peak limitation, response time and resistance attained during fault limitation have been compared for AC over-current pulses of 1.5 kA for 100 ms duration. The aforesaid measurements helped us to select a suitable high Tc superconductor for fastest effective fault limitation to be used in R-SFCL application.