DECOMPRESSION PUMPING SYSTEM FOR HTS POWER CABLE AND COOLING METHOD FOR USING THE SAME

摘要

PURPOSE: A decompression refrigeration system for cooling a superconductor cable and a cooling method using the same are provided to reduce maintenance costs by re-condensing the gas of a discharged refrigerant to be used as a refrigerant, thereby avoiding the waste of the refrigerant. CONSTITUTION: A sub-cooler(110) cools down liquid nitrogen circulating through a superconductor cable, and a decompression pump(120) decreases the temperature of a refrigerant in the sub-cooler by controlling the vapor pressure of the sub-cooler. At this time, a low-temperature gas heating heater(130) and a buffer tank(140) protect the decompression pump from a low-temperature gas. The rear end of the decompression pump discharges a nitrogen gas vaporized from the sub-cooler, and an ultra-low temperature freezer(150) re-condenses the nitrogen gas discharged from the decompression pump. A refrigerant storage tank(160) stores liquid nitrogen re-condensed from the ultra-low temperature freezer and supplies the stored liquid nitrogen to the sub-cooler. A gas-liquid separator(170) is located between the refrigerant storage tank and the sub-cooler and maintains the liquid nitrogen as a refrigerant at an atmospheric pressure and supplies low-temperature liquid nitrogen to the sub-cooler. A circulation pump(180) circulates the liquid nitrogen as a refrigerant and cools down the superconductor cable by circulation. [Reference numerals] (110) Sub-cooler; (120) Decompression pump; (130) Low-temperature gas heating heater; (140) Buffer tank; (150) Ultra-low temperature freezer; (160) Refrigerant storage tank; (170) Gas-liquid separator; (180) Circulation pump; (AA) Cooling; (BB) Superconducting cable; (CC) Circulation;