Liquid Hydrogen Cooling System for 100 kW-Class HTS Rotor Thermal Design

This study introduces a cooling topology for a rotating field coil that integrates the supply of liquid hydrogen (LH
₂
) fuel with the cooling flow path in a High Temperature Superconductor (HTS) motor. The distinguishing feature of this system is the use of cryogenic LH
₂
as both refrigerant supplied to the HTS rotor and fuel supplied to a fuel cell. The HTS rotor is fitted with a simple reservoir-shaped heat exchanger and includes both thermal and mechanical design considerations. To supply LH
₂
to the high-speed rotating HTS rotor, a cryogenic coupling structure is implemented using a coaxial triple pipe that includes both vacuum insulation layer and Ferro fluid seal. This research describes design process to minimize external heat load and ensure cooling down to 30 K during initial cooling and operation. In addition, thermal analysis is conducted through a commercial FEM analysis in consideration of the rotor components. Based on the design process and results, the fabrication and performance evaluation of the HTS rotor will be conducted.