## 5 Conclusions  
In this study, the performance of an r-SFCL was investigated while considering the effects of different shunt resistor values. Without the r-SFCL, the fault current reached a peak of 6.25 kA. The r-SFCL with the 4 \(\Omega\) shunt resistor could limit the fault current to 3.9 kA, representing 62.4% of the prospective current. On the other hand, the 16 \(\Omega\) shunt resistor further reduced the fault current to 39% of the prospective current (only 2.44 kA). There was a clear trade-off between the shunt resistor value, the fault current limiting capability, and the developed temperature. When the shunt resistor value was the largest, the fault current limiting capability was the maximum, but the temperature was the highest. The main goal of using an r-SFCL device is to reduce the fault current to below the CB rating to ensure safe operation of the CB. However, there are several constraints on the fault current limiting capability. The fault current should not be reduced to below the pickup point of the CB; this will cause a fault detection problem where the protective relays cannot detect the fault current. The second constraint is the thermal constraint; the temperature of the r-SFCL should not exceed its permanent damage temperature (>400 K). As a result, the r-SFCL should reduce the fault current to below the CB rating but above the CB pickup point, and the r-SFCL temperature should be maintained below 400 K. Testing the r-SFCL with different shunt resistors can lead to the ideal combination to deal with the constraints. Based on the results, the shunt resistor value strongly affects the performance of the r-SFCL. The proper shunt resistor value should be selected to effectively limit fault currents while maintaining the safe operation of the r-SFCL. In this paper, the r-SFCL is constructed using AMSC-8062 superconductor tape. The AMSC-8062 superconductor tape has been modeled carefully with all parameters sourced from experimental works. The temperature-dependent resistivities of all layers, dissipated power, cooling power, and heat capacities (Cp) for all layers have been implemented in the model. The system has been carefully modeled to provide accurate results and to build a strong base for future work, which would be constructing an experimental prototype to practically investigate the effect of shunt resistors on r-SFCLs based on AMSC-8062 superconductor tape.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Shunt Resistor** & **First Peak** & **Highest Temp.** & **Recovery Time** \\
**(\(\Omega\))** & **(kA)** & **(K)** & **(s)** \\ \hline
4 & 3.9 & 195 & 5.77 \\
8 & 3.1 & 294 & 7.78 \\
16 & 2.44 & 384 & 9.88 \\ Without shunt & 1.45 & 499 & Not recovered \\ \hline \hline \end{tabular}
\end{table}
Table 3: Comparison of obtained performance indices of r-SFCL with different shunt resistors.  
**Author Contributions:** Conceptualization, H.A., X.P. and D.-E.A.M.; methodology, H.A., M.K. and I.A.; software, H.A. and M.K.; validation, X.P., X.Z. and D.-E.A.M.; formal analysis, H.A., A.A. and M.A.; resources, H.A.; writing--original draft preparation, H.A.; writing--review and editing, D.-E.A.M., X.P., M.A., A.A., M.K., I.A. and X.Z; supervision, X.P. and D.-E.A.M. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research has been funded by the Scientific Research Deanship at the University of Ha'il, Saudi Arabia, through project number RG-21 087.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Not applicable.  
**Conflicts of Interest:** The authors declare no conflict of interest.