Influence of Flux-Flow and Terminal Contacting as Well as Dynamic Resistances Due to Ripple Current on Performance of the km-Class HTS DC Cable

High temperature superconducting (HTS) direct current (DC) cables have recently gained interest and are being considered for some applications because of their intrinsic zero resistance and high current density. However, due to the unavoidable harmonic currents in practical DC transmission systems, the issues of AC loss and dynamic resistance of HTS DC cables have to be paid much attention. Besides, for a high voltage transmission line with a length of more than several kilometers, the flux flow and contacting resistances should be calculated simultaneously. In this paper, E-I power law instead of the critical state model (CSM) is adopted and temperature variation caused by cable length are considered in analyzing the characteristics of HTS DC cable. A 1 km/5 kA HTS DC cable based on the principle of uniform current is designed considering three types of resistances comprehensively, which is significant to the development and operation of HTS DC cables toward practical long transmission distance.