Electrical characteristics and transient analysis of HTS DC power cables for shipboard application

Physical and electrical characteristics of high-temperature superconducting (HTS) DC power cables have been modelled to assess their benefits compared to conventional XLPE cables for use in distribution networks of tightly coupled electrical systems such as the Navy all-electric ship. The characteristics of a 30-m long HTS DC cable prototype that was successfully demonstrated recently were used to evaluate the benefits of increased power density, both volumetric and gravimetric, in comparison with similarly rated XLPE cables. The response of HTS cables for electrical faults and switching harmonics were studied through electrical models. The results of transient characteristics of HTS cables were compared to that of normal cables under identical network conditions. The peak voltage observed for the HTS cable network when faulted was considerably smaller than that of the XLPE bundle under a 1 kΩ ground resistance. On the contrary, the over voltage of the ungrounded HTS cable system was larger than that of the XLPE cable. The damping constant of the HTS cable was 3 times higher than XLPE cable.