초전도 발전기용 네온 재응축 냉각 시스템 개발

HTS (High Temperature Superconductor) technology enables compact and high efficient power generators. To keep the superconducting state, the HTS rotor should be cool down to cryogenic temperature. In general, it is known that the optimum operation temperature is about 30 K considering the cost of the HTS conductors and cooling system. Therefore, cooling system should be designed to keep the temperature of the HTS rotor around 30 K. This can be realized by using the liquid neon thermosyphon cooled by crycooler. This paper describes the design process and experimental results for liquid nitrogen re-condensing cooling system. Heat loss of the torque tube is estimated. Flow areas for liquid and gaseous neon are determined considering the pressure drop. Experiments are performed to estimate the background loss of the cooling system itself and to investigate the heat loss through the torque tube. Additional heating is applied to verify the performance of the cooling system.