电工装备中的叠层硅钢片电磁特性模拟与涡流场计算方法研究

Three-dimensional analysis of the eddy current fields in laminated cores of electrical equipments is a weak link in the research field of electromagnetic theory and applications in electrical engineering, and there has not been an ideal solution until now. An accurate modeling of the electromagnetic properties of the laminated core, especially the properties introduced from the lamination structure which are known as the overall properties and are different from the case of a single steel sheet, is the premise of the correct implementation of the eddy current field analysis of the laminated silicon steel sheets. This project aims to study the basic theory for applications concerning the fast calculation of the eddy current field in the laminated core. The characteristic tests for the typical electrical test models and the two-dimensional electromagnetic properties measurement system are planned to be implemented under all possible working conditions, especially under the extreme conditions, and the impacts of the magnetic field, pressure, temperature, and frequency on the electromagnetic characteristics, taking the magnetic flux and iron loss as the main index, are planned to be investigated; the mathematical models for the electromagnetic characteristics of the laminated core, in the light of the magnetic domain theory, are expected to be proposed, the comprehensive method and the basic theoretical system of the three-dimensional eddy current field analysis are expected to be established, and the reliable basic platform for applied science and technology is to be provided for the performance analysis and optimal design of electrical products; based on the research of the eddy current field analysis, the simple and accurate iron loss calculation method is to be explored in order to improve the design accuracy of electrical equipments, and to improve the operating efficiency and reliability.

电工装备中的叠片铁心三维涡流场分析是电气工程电磁场理论及应用研究领域的薄弱环节，长期以来一直没有理想的解决方案。而叠片铁心电磁性能的精确模拟，尤其是由于叠层结构所引入的、有别于单片硅钢片情况的整体电磁特性建模，是正确实施叠层硅钢片涡流场分析的前提。本项目致力于叠层硅钢片涡流场快速计算的应用基础理论研究。拟通过对典型电工测试模型和二维电磁特性测量系统在各种可能工况条件下尤其是极端条件下实施特性测试实验，以磁通和铁耗为主要考察指标，研究磁场、压力、温度和频率等参数对电磁特性的影响；提出基于磁畴理论的叠片铁心电磁特性数学模型，建立完善的叠层硅钢片三维涡流场分析方法和基础理论体系，为电工产品的性能分析和优化设计提供可靠的应用科学技术基础平台；结合涡流场分析的研究成果，探索简便而精确的铁耗计算新方法，以提高电工装备的设计精度，提高装备运行效率及可靠性。

本研究项目在电磁验证模型及测量系统的设计与实现、磁性材料的等效磁特性表述以及涡流磁场计算方法等方面取得了显著进展。具体研究成果如下：（1）以多种规格硅钢片分别构建了单框型、环形和UI型交变磁化电磁验证模型，开展了在不同激励大小、频率、工作温度等条件下的实验。旋转磁化测量系统搭建方面，目前已完成了电磁理论计算及铁心磁路拓扑结构的初步设计。（2）提出了一种非线性涡流问题的线性化表述，该表述的核心是引入了用以计及叠片/实心铁心磁饱和效应的等效磁导率。这种的线性化处理方法能大幅减少数值计算代价，而在引入等效磁导率过程中，理论上只需借助铁磁材料的直流磁化曲线进行计算，而无需考虑各种励磁频率下的交流磁化特性。（3）以永磁涡流联轴器为分析对象，提出了一种新的、针对运动导体涡流问题的解析计算模型。该解析模型中，永磁阵列的磁特性及不同形状永磁体之间的等效关系等问题得到了充分且合理的考虑。此外，由于引入了等效磁导率的概念，从而得以成功利用纯解析方法分析铁区涡流及其所引起的磁饱和效应。