Magnetic-thermo-structural coupling analysis of windings for air-core compulsators

Air-core compulsator, as a pulsed power supply with high energy density and high power density, operates under the condition of high speed, high current and strong magnetic field¹. Besides the mechanical forces due to high rotating speed, the high current and strong electromagnetic field will induce very high electromagnetic forces in the compulsator. The extreme electromagnetic forces were applied directly to the fragile armature windings of air-core compulsator than the ferromagnetic slot walls with much higher strength of iron-core compulsator. Therefore, it is very necessary to analysis and evaluate the strength of armature windings for the safe operation and life span of air-core compulsator. The magnetic-structural coupling analysis of armature windings was analyzed and the stress distribution was presented during discharge in the paper². The copper loss due to high discharge current will produce thermal stress in the armature windings during discharge. In the stress analysis of armature windings, the thermal stress effects were considered, especially in the condition of repetitive pulsed current supply for railgun. According to the peak stress distribution of different structures of armature windings, a safe and optimal structure of armature winding was designed. According to the stress distribution characteristic of air-core compulsator, the stress strength requirements were determined for the stator and rotor windings in the radial and tangential direction. Finally, an integral forming technic method was presented for the manufacture of composite stator and rotor components of air-core compulsator.