Magnetic dipole collectives for modelling the ferromagnetic material characteristics in electrical machines

用于模拟电机中铁磁材料特性的磁偶极子集合

• 批准号: 393466659
• 负责人: Professor Dr.-Ing. Ingo Hahn
• 金额: --
• 依托单位: Lehrstuhl für Elektrische Antriebe und Maschinen
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/393466659?language=en
• 关键词: Magnetic; dipole; collectives; modelling; ferromagnetic

Modern numerical electromagnetic field computation of electrical machines uses the magnetization curve to describe the nonlinear ferromagnetic material characteristics of the iron parts. The mean magnetization curves are obtained by measurements taken from a ring specimen tester or an Epstein frame. The scientific literature provides different hysteresis models which are either based on mathematical or physical equations or which are of phenomenological nature. Common models are e.g. the Preisach model, the Jiles-Atherton model and the Landau-Lifshitz model. The first two of them describe the macroscopic, transient behaviour of the magnetization dependent on the external magnetic field intensity as ordinary differential equations. However, both of these models neglect the local magnetic field distribution within the active iron parts of the machine.However, the Landau-Lifshitz model describes the microscopic behaviour of ferromagnetic materials. Based on different interactions, the alinement of elementary dipoles (magnetization vectors) is optimized mathematically to minimize the total free energy of the system. The interactions can be derived from physical relations that are based on the crystal structure and the texture of the material at the atomic scale.The model investigated in detail in this project abstracts the physical relations provided by the Landau-Lifshitz model and transfers them to a macroscopic grid. Therefore, comprehensive preliminary studies with two- and three-dimensional collectives of magnetic dipoles were performed. The results obtained in this studies show a qualitative good agreement between simulated and measured values. The dipoles within the collective of the presented model interact according to the stray-, exchange and anisotropy field, as it they are formulated in the Landau-Lifshitz-Model.Because of the above-mentioned abstraction of the Landau-Lifshitz-Model the physical relationship of the parameter set, which belongs to the model under investigation, is lost for the moment. In order to rebuild this relationship, first it is necessary to develop a standardized parameter identification process that is, as far as possible, guided by physical observations on the sample and the different excitation conditions. In a second step, from the found qualitative relationships, quantitative connections between the parameter set and the measured hysteresis behaviour will be deduced.Summing up, the aim of this project is a comprehensive investigation of the introduced dipole model in term of its abilities of imitating and predicting quantitatively the hysteresis behaviour of macroscopic structures considering different external influences on the material sample.

现代电机电磁场数值计算采用磁化曲线来描述铁质部件的非线性铁磁性材料特性。平均磁化曲线是由环形试样测试仪或爱泼斯坦框架测量得到的。科学文献提供了不同的滞后模型，这些模型要么基于数学或物理方程，要么具有现象学性质。常见的模型有Preisach模型、Jiles-Atherton模型和Landau-Lifshitz模型。它们中的前两个描述了依赖于外部磁场强度的磁化的宏观瞬态行为作为常微分方程。然而，这两种模型都忽略了机器有效铁部件内的局部磁场分布。然而，Landau-Lifshitz模型描述了铁磁材料的微观行为。基于不同的相互作用，数学优化了基本偶极子的间距（磁化矢量），使系统的总自由能最小。这种相互作用可以从基于晶体结构和材料在原子尺度上的质地的物理关系中推导出来。本项目详细研究的模型抽象了Landau-Lifshitz模型提供的物理关系，并将它们转移到宏观网格中。因此，对二维和三维磁偶极子集体进行了全面的初步研究。研究结果表明，模拟值与实测值在定性上有很好的一致性。所提出的模型集合内的偶极子根据杂散场、交换场和各向异性场相互作用，就像它们在landau - lifshitz模型中表述的那样。由于上述对landau - lifshitz模型的抽象，暂时失去了属于所研究模型的参数集的物理关系。为了重建这种关系，首先有必要制定一个标准化的参数识别过程，该过程尽可能以对样品的物理观察和不同的激励条件为指导。在第二步，从发现的定性关系，定量连接参数集和测量迟滞行为将推导。综上所述，本项目的目的是对引入的偶极子模型进行全面的研究，以其模拟和定量预测宏观结构在考虑不同外部对材料样品的影响时的滞后行为的能力。