A field-circuit model enhanced with thermal-hydraulic behaviors for evaluating fault endurance and recovery of HTS power cables

Abstract The advantages of low loss and high power density in high-temperature superconducting (HTS) power cables render them promising candidates for urban power transmission applications. Numerical simulation models, especially field-circuit coupling models, are adept at capturing the interactions between cables and power grids during transient short-circuit faults. However, a significant limitation in current research is the lack of integration of cable thermal-hydraulic behavior into these models. In finite element model models, kilometer-long cables present challenges due to their large geometric aspect ratios, and high-current short-circuit faults can further complicate computational convergence. Addressing this, this paper proposes a simulation framework that enhances field-circuit coupling models by incorporating a scaled-length thermal-hydraulic model and optimizing the E-J relationship of HTS tapes under fault conditions. This paper also investigates the fault endurance of the cable in given power grid, explores reclosing strategies based on the maximum self-recovery temperature, and evaluates load recovery capability, finding that backup overheating protection and reclosing strategies utilizing non-electrical quantities can drastically reduce the cable outage duration while boosting the equipment utilization of the cable by 99.71%.