Abstract：：The doubly skewed rotor induction motor is a novel type of motor to improve the performance of ordinary skewed rotor induction motors. However, the effects of the inter-bar currents and axial variations in saturation on its starting performance have not been fully studied. In order to accurately calculate the starting torque, based on three-dimensional finite element transient field, a model considering inter-bar currents and axial variations in saturation was established. An equivalent circuit parameter method considering the variations in main leakage reactance was proposed to calculate the starting torque performance of doubly skewed rotor induction motor. Meanwhile, the air-gap magnetic flux density was studied to explain that three-dimensional finite element models can take into account the axial variations in saturation. The relationship between inter-bar resistance and torque-speed curve was investigated by simulating the finite element models of different inter-bar resistances. The calculated results were compared with the results of the virtual displacement method and the measurements, which indicated that the proposed method can accurately calculate the starting torque performance.
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2019, Vol. 34 
