Research On Key Issues Of Two-Dimensional Magnetic Property Measurement Of Electrical Steel Sheets

Electrical steel sheet has very complex non-linear magnetization characteristics. It is the most widely used magnetic material in electrical products. In order to reduce loss and realize the optimal design of integrated performance, accurate simulation of electrical steel sheet is needed in the numerical analysis of electromagnetic field in electrical machines and apparatus. Presently, the measuring methods of magnetization characteristics are Epstein Frame and Ring Specimen. But both of them have shortcomings in measuring principle and method, which doesn't meet the need of accurate simulation of electrical steel sheet. Through the detailed research of both methods and aiming the shortcoming of measuring principal and method, a 2D measuring method of magnetization is attracted by researchers. Aimed to the 2D measuring system, several key problems are deeply studied in this paper.Tasks accomplished in this paper are as follows:First, the background and development of measuring method of magnetic characteristics of electrical steel sheet are introduced. By referring related papers, the whole process of measuring method of magnetic characteristics is presented and an experimental model is designed.Second, the design of power amplifier in exciting electrical source is a key part when 2D magnetic field is measured. In this experiment, an amplifier which can be used for 2D magnetic measurement is made. Besides, isolation amplifier which is used for isolating signal is also an important point in designing.Third, with the rapid development in computer, electronics and software technology, virtual instrument technology has been a new trend in measuring and controlling area. In this experiment, Virtual Instruments is applied to the data collecting part in 2D magnetic measuring, making the interface of measuring system friendly, more accurate and easy updated. Last, the conclusions of the whole research are given, and some unsolved problems are presented and some advices are proposed for (next step) further study.This thesis is a part of the natural foundation project, "The fine simulation of comprehensive electromagnetic properties of the electrical steel sheet and its composite structures in the computational electromagnetics". As the beginning step of this project, design of whole measuring system is introduced and some key problems in testing are discussed, hence a basis for further study is laid.