AC Loss Analysis of 10-MW High-Temperature Superconducting Double-Stator Field-Modulation Generators and Its Reduction

In this paper, the ac losses of one 10 MW high temperature superconducting double-stator field-modulation generator is analyzed and the detailed principle of the machine and the armature reaction field effects on superconducting coils are conducted. For this machine, the fundamental rotating magnetic field can directly generate ac magnetic field on these stationary hightemperature superconducting coils which may lead to large ac losses and excessive cool budget. In order to reduce the ac losses, some inhibition methods such as increasing slot opening height, applying copper shield layer and flux diverter are proposed. The results show that the perpendicular component of the ac magnetic field around the superconducting coils can be effectively weakened.