Study on AC Over-Current Transport Characteristics of the ReBCO Thin-Film-Type Superconducting Wire with the Different Specific Resistance Values

The main goal of the superconducting cable is lossless power transmission, and it does not function the fault current limiting performance. In this study, the use of the fault current limiting type superconducting power cable model is proposed to maximize its current limiting performance within the stable range using only the relationship between the current transporting and current limiting parts, without additional devices. For this, the current transporting and current limiting parts were configured using ReBCO thin film wires with different specific resistance characteristics, and a jig was fabricated to integrate the whole parts. After a fault current was applied, the current transporting, current limiting, and thermal stability characteristics were examined. The current transport characteristic was normal under the suggested condition, and the current limiting rate also complied with the operation condition at the 1/2th, 3rd, and 5.5th cycles. The thermal stability was analyzed, and the temperature of the current limiting part increased to 270 K at the 5.5th cycle, which might present a possibility of damaging the superconducting wires. The aforementioned results are highly valuable as the basic data for the design of fault current limiting superconducting cables.