Current-Limiting and Recovery Characteristics of Resistive-Type Superconducting Fault Current Limiters During Quench-Recovery-Requench Process

Resistive-type superconducting fault current limiters (R-SFCLs) can limit short-circuit fault currents and have a good future in HVdc systems. The system can be reclosed when the R-SFCLs return from the quenched state to the superconducting state. If the short-circuit fault is permanent, the R-SFCLs will be quenched for the second time after the system is reclosed. The second quench and recovery characteristics of R-SFCLs in liquid nitrogen (LN
₂
) are crucial for the reclosing of a flexible dc systems. However, the recovery characteristics of high temperature superconducting (HTS) tapes after the second quench are still unclear. Thus the objective of this article is to obtain the effect of the quench-recovery-requench process in LN
₂
on the current-limiting and recovery characteristics of HTS tapes. In this article, both experimental and simulation methods are used to study the recovery characteristics of HTS tapes after two quenches. The effects of the amplitude of the current and the requench speed on the recovery time of the HTS tape are also analyzed. The results showed that when the HTS tape was in a “critical recovery” state, the HTS tapes does not recover to 77 K after the first quench. The recovery time for the second quench was 2.48 times that of the first quench; when the reclosing time is reduced from 0.5 to 0.3 s, the maximum temperature of tape after the second quench has a 17.3% increase. Finally, by comparing the simulation with the experimental data the maximum error is less than 20%, which verifies the feasibility of the simulation design method.