Development of a 70 MW class superconducting generator

A national project to develop a superconducting generator was begun in 1988 in Japan under the New Sunshine Project of AIST, MITI. This generator has merits of higher efficiency and compactness for transmission lines. A 70 MW class superconducting generator is the goal of the project. The authors have been developing a rotor having a superconducting field winding and a stator having an air-gap armature winding. The field winding was designed to be cryostable so as to recover from a partial transition to normal conduction. The field winding was tested in a nonrotating cryostat, and excitation performance and stability were confirmed to be enough for the 70 MW class superconducting generator. The rotor and the stator have been completed and a shop test is being made.