This article concerns the modeling and design of a slitted stator core for single-sided axial-flux permanent-magnet machine application. The stator core is specially designed to maximize the magnetic-flux density in the air gap and to minimize the eddy-current losses occurring at high rotational speeds. To reduce the effort needed for computing the motional eddy-current distribution in the presence of nonlinear material characteristics, a novel method is proposed. It combines the harmonic balance method, which is advantageous for simulating in the frequency domain the steady-state periodic response of a nonlinear system under harmonic excitation, together with a source description that introduces a complex magnetization that mimics the displacement of the permanent-magnet array. Following this method, time-domain distributions and losses can be reconstructed accurately with a low number of harmonics. A 3-D periodic model of the slotless axial-flux machine is built in the framework of isogeometric analysis (IGA) and a mixed formulation is employed, which relies on high-order Nédélec edge elements. The proposed model is embedded into a gradient-based optimization problem to determine the optimal shape of the slits in the stator core of the motor. This results in a novel cost-effective solution for improving the efficiency of axial-flux permanent-magnet machines.

中文翻译：

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轴向磁通永磁电机开缝定子铁芯中的运动涡流分析

本文涉及用于单面轴向磁通永磁电机应用的开缝定子铁芯的建模和设计。定子铁芯经过专门设计，可最大限度地提高气隙中的磁通密度，并最大限度地减少高转速下出现的涡流损耗。为了减少在存在非线性材料特性的情况下计算运动涡流分布所需的工作量，提出了一种新方法。它结合了谐波平衡方法，这有利于在频域中模拟谐波激励下非线性系统的稳态周期响应，以及引入复杂磁化的源描述，模拟永磁体阵列的位移. 按照这个方法，时域分布和损耗可以用少量谐波准确重建。在等几何分析 (IGA) 的框架中建立了无槽轴向磁通机的 3-D 周期模型，并采用了依赖于高阶 Nédélec 边缘元素的混合公式。将所提出的模型嵌入到基于梯度的优化问题中，以确定电机定子铁芯中狭缝的最佳形状。这为提高轴向磁通永磁电机的效率提供了一种新型的经济高效的解决方案。将所提出的模型嵌入到基于梯度的优化问题中，以确定电机定子铁芯中狭缝的最佳形状。这为提高轴向磁通永磁电机的效率提供了一种新型的经济高效的解决方案。将所提出的模型嵌入到基于梯度的优化问题中，以确定电机定子铁芯中狭缝的最佳形状。这为提高轴向磁通永磁电机的效率提供了一种新型的经济高效的解决方案。