We introduce a conceptual design of a MW class power system consisting of SiC power electronics and liquid nitrogen cooled superconducting cable. This design is for a hybrid aircraft with two 2.5MW class motors (propulsors). The framework of this study consists of three components. First one is a high-power density power conversion using SiC power devices. The second one is high-power density power transmission using superconducting cable with liquid nitrogen cooling. The last one is the optimization of the power system specifications. In this presentation, we focus on the second topic about the superconducting transmission cable. Here, we have estimated the size and weight of the power cable system, and clarified the advantages of HTS (High Temperature Superconductor) power transmission cable. The electric and thermal insulation of the cables and terminals are discussed. Based on these results, the liquid nitrogen cooled power cable and the terminal are designed.

Keywords: Hybrid Aircraft, MW class power system, power transmission cable