AC Loss Analysis of 35 kV High Temperature Superconducting Cables

The alternating current (AC) loss is a key consideration of the operation economy and stability of the high temperature superconducting (HTS) cables. In this paper, the sources of the AC loss in the HTS cable are analyzed firstly. The three-phase HTS cable, adopted in the 35 kV km-level HTS cable demonstrating project in Shanghai, China, is modeled by the finite element method (FEM) to calculate the AC loss by the COMSOL Multiphysics. The AC loss of the designed 35 kV HTS cable is 1.31 W/m. The theoretical calculation method is also implemented to verify the modeling results. Furthermore, considering the on-site conditions of the demonstrating project in Shanghai, China, the calorimetric method is conducted by measuring the temperature difference between the inlet and outlet of liquid nitrogen. The obtained results provide useful indications for the future design and research of HTS AC systems.