Cryogenic refrigeration system is necessary for cooling superconducting motor or generator. Among the various forms of cryogenic refrigeration system, an on-board hybrid pulse tube cryocooler was investigated. Hybrid pulse tube cryocooler was composed of pulse tube cryocooler and Stirling cryocooler. The Stirling cryocooler precooled the regenerator of the pulse tube cryocooler at the middle point to produce lower temperature at the cold end of the pulse tube cryocooler. The hybrid cryocooler was aligned in the rotor to have the concentric center line and the rotation axis. In this thesis, first, Stirling cryocooler was on-boarded and pre-tested to check the performance variation for various rotating speeds. Then the pulse tube cryocooler was designed and fabricated based on adiabatic model and loss mechanism analysis. Hybrid pulse tube cryocooler was then assembled and the rotation experiment was performed with external motor. Even if the performance of hybrid pulse tube cryocooler was not satisfactory, the cooling performance degradation was investigated for various rotating speeds. The feasibility of new cooling method for superconducting rotor, the on-board cryocooler, is identified.
