Experimental Results of Various Optical Fibers Encapsulated HTS Tapes Under Impulse Currents for the SFCL Application

In high temperature superconducting (HTS) applications, effective and fast quench detection techniques are quite essential. Recently, an attractive combination of distributed optical fiber sensor and optical fiber encapsulated HTS tape (OF-tape) is suggested for quench detection. Before OF-tapes are applied in actual applications, their performance should be tested previously. In this paper, three types of OF-tapes, whose optical fiber diameters are 95, 170, and 250 μm, respectively, were prepared for our superconducting fault current limiter (SFCL) project, and these tapes are named tape-95, tape-170, and tape-250 in sequence. The SFCL requirements show that for the used HTS tapes, the critical current, the room temperature resistance, and the bearable AC impulse current must be within 500 ± 10% A, 60 mΩ/m, and 1500 A/100 ms, respectively. The test results indicate that the critical currents of tape-95, tape-170, and tape-250 are approximately 500 A, and the room temperature resistances of these tapes are 70, 65, and 57 mΩ/m, respectively. Moreover, the AC 1500 A/100 ms short circuit current will not damage these tapes seriously. According to the SFCL project requirements and these test results, tape-170 will be used in limiter coils.