AC Loss Characteristics of HTS Field Winding for Synchronous Motor According to Stator Configuration

In the case of a synchronous motor, magnetic field variation occurs at the field winding due to field harmonics of non-perfect sinusoidal armature MMF and reluctance change caused by iron-cored stator teeth. So it is necessary to quantitatively analyze the AC loss value of the HTS field winding even for synchronous operation. This paper presents calculation results of AC loss of HTS field winding in synchronous motor considering armature harmonics and slotting effect. We selected two models with different stator topologies: 1) distributed-winding air-cored teeth (DWAT) and 2) concentrated winding iron-cored teeth (CWIT). Then we used 2D A-H formulation for AC loss calculation of HTS field winding according to stator configuration. Through this research, it was confirmed that the CWIT model had three times greater AC loss in synchronous operation due to larger harmonic components.