AC Loss Analysis of Parallel Superconducting Coil Used in Multiphase Superconducting Armature Permanent Magnet Electrical Machine

The phase current of mega watt (MW) class superconducting (SC) armature permanent magnet electrical machine (SCPMM) is quite high, usually from several hundred amperes to 1 kA, therefore, the current-carrying capacity of a single SC tape is insufficient to meet the phase current requirements. The main purpose of this article is to investigate a kind of parallel SC coils and analyze the arrangement of multiphase SC armature windings and its loss regularity under external magnetic fields. The main effect factors of parallel SC coils on ac loss are obtained under the conditions of self-field and external periodic magnetic field and a kind of arrangement of the low-loss parallel coils are proposed through coordinating spatial distribution of SC coils and phase shift of transmitting current. This work provides references for the design optimization multiphase SCPMSM.