Integrated operational characteristic simulations of a ±100 kV/1 kA superconducting DC energy pipeline based on multi-physics interaction

The superconducting DC energy pipeline (SEP) is a promising technology, which has the ability to transmit electricity and fossil energy such as liquefied natural gas (LNG) at the same pipeline so that LNG could serve as the refrigerant for the high-temperature superconducting (HTS) cables. Therefore, the collaborative transportation of electricity and LNG increases the efficiency while lowering the cost. However, the integrated operational performance of the SEP, which is crucial for HTS cables and LNG, is of greater complexity on account of multi-physics interactions. Herein, a ±100kV/1kA SEP model with the electric, magnetic, fluid and thermal fields is established in COMSOL Multiphysics to analyze the temperature distribution of SEP via parametric scanning on SEP heat leakage and distance between refrigeration stations. The simulation results show the relationship between temperature and transmission distance of a SEP based on the interactions of the multi-physics fields. The results indicate that the maximum temperature rises by 11.6 K for every kilometer of SEP. Moreover, the influences of heat leakage and LNG flow on temperature rise are revealed. Temperature rise increases proportionally with heat leakage and it decreases monotonously with LNG flow. This study validates the feasibility of SEP and provides the theoretical references for the demonstration application of SEP.