Analysis of Inter-Turn-Short Fault in High-Speed Permanent Magnet Generators Considering Effect of Structure Windings

Inter-turn short faults (ITSF) are common and serious in motor windings, particularly in high-speed motors. To improve the motor performance under the fault as much as possible, it is necessary to clarify the harm of ITSF from high-speed motors with different winding structures. In this article, the influence of ITSF on the properties of high-speed permanent magnet generators (HSPMG) with toroidal winding (TW) and distributed winding (DW) is studied. The TW and DW fault models are established, and the electromagnetic characteristics of the HSPMG after the ITSF are analyzed using the field-circuit coupling method. The temporal and spatial distribution of the air-gap magnetic field under fault is given, and the mechanism of asymmetry in the magnetic field is revealed. Secondly, based on the Fourier transform method, the characteristics of the electromagnetic force under different working conditions are analyzed, and the characteristics of the electromagnetic force harmonic caused by the short-circuit current are obtained. In addition, the vibration acceleration response of the stator is calculated by modal and harmonic response analysis, and the vibration characteristics of the generator after the ITSF are obtained. Finally, the electromagnetic performance of the prototype is tested to verify the correctness of the theoretical analysis.