Transient analysis of HVDC HTS cable in power grid using discretized electrical-thermal model

High-temperature superconductor (HTS) power cables hold immense potential for efficient, low-loss, high-current-density, and compact power transmission. However, the susceptibility of HTS cables to faults in the grid, resulting in quenching or permanent damage due to joule heating, poses a critical challenge for their real-world resilience. To address this, we developed a discretized electrical-thermal model using MATLAB/SIMSCAPE, partitioning the cable into discrete blocks to understand transient conditions and implement preventive measures in long-distance superconducting cable power transmission. The model should have the flexibility to change the fault location along the length of the cable, including the HTS and copper former and LN 2 layers. In our simulations, we examined a 100 km long 100 kV/10 kA HVDC HTS cable, varying the fault locations to 1, 5, 50, and 100 km. This investigation unveiled significant variations in both thermal and electrical behaviour, more impact was observed when faults occurred in proximity to the voltage source. This study underscores the benefits of integrating Superconducting Fault Current Limiters (SFCL) with HTS cables in the network, showcasing load sharing between the superconductor and copper former during steady and transient state operation, HTS quench and recovery time.