不同定子槽形潜水电机空载时表面损耗的研究(英文)

Analysis of Eddy Current Losses on Surface of Submersible Motor with Different Stator Slot Types at No-Load Condition

由于潜水电机特殊的运行环境,其定子通常采用闭口槽结构。本文选用定、转子同为闭口槽的潜水电机为原模型,对其转子上空载时的涡电流与涡流损耗进行了研究。首先通过解析法推导分析了卡特系数、气隙磁导、由定子槽开口引起的齿谐波磁场以及转子表面的涡流损耗。其次建立四种定子槽形模型,用二维有限元法对其磁场特征进行了分析,特别是由开槽引起的齿谐波磁场。通过与原闭口槽模型进行对比,半开口和全开口槽模型中由定子开槽引起的定子齿谐波磁场则可利用矢量合成法从总的定子齿谐波中分离得到。最后,分别用解析法和有限元法对各个模型中转子涡电流与转子涡流损耗进行了分析。由于有限元法考虑了电机中磁饱和和材料的非线性问题,其计算结果与解析的结果存在一点差距。根据文中结果表明,本文所提出的改进的定子闭口槽模型相比于开口槽和原闭口槽具有更小的转子表面损耗。

Due to the special operation conditions,the stator of submersible motor is generally adopted closed-type-slot.In this paper,the rotor eddy currents as well as the rotor eddy current losses at no-load condition in a submersible motor which consist of the closed-slot stator and closed-slot rotor were investigated.Analytical method was developed to evaluate the Carter Factor,the air-gap permeance,the tooth harmonic fields caused by stator slotting,and the eddy current losses on rotor surface.The magnetic fields especially the tooth harmonic fields caused by slotting effect in four stator slot models were analyzed by the transient two-dimensional finite element method（2D FEM）.Full-open slot model and semi-open slot model were constructed to make a comparison with the original slot model.Then the stator tooth harmonic fields caused by stator slotting were separated from the total stator tooth harmonics by vector composition method.The rotor eddy currents as well as the rotor eddy current losses of the models with different stator slot types were analyzed.There is a little difference between the analytical results and the FEM results since the FEM method considered the magnetic saturation and material nonlinearity.Finally,it is found that the rotor surface loss of the model with improved stator slots is much smaller than that of the model with open slots and original slots.