考虑横向电流和饱和轴向变化的双斜槽转子感应电机起动转矩分析

Starting Torque Analysis of Doubly Skewed Rotor Induction Motor Considering Inter-Bar Currents and Axial Variations in Saturation

双斜槽转子感应电机是一种能提升普通单斜槽转子感应电机性能的新型电机,横向电流和磁场饱和轴向变化对其起动性能的影响未得到充分研究。为了精确计算双斜槽转子感应电机的起动转矩,基于三维有限元瞬态场,本文建立一种考虑横向电流和磁场饱和轴向变化的双斜槽转子感应电机分析模型。提出一种考虑主电抗变化的等效电路参数法,精确计算双斜槽转子感应电机的起动转矩特性。同时通过分析气隙磁通密度的轴向变化来说明三维有限元分析模型能考虑磁场饱和轴向变化,通过仿真不同横向电阻值的有限元模型来探究横向电阻与转矩-转速曲线的关系。与有限元中的虚位移法和实验相比,计算结果证明了所提方法能够精确计算双斜槽转子感应电机的起动转矩。

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.