## 3 Experimental Verification  
### Experimental Principles and Platform Construction  
In the study of magnetic properties, the design of the experimental platform is the basic link. Nowadays, experimental measurement devices for magnetic properties continue to receive a lot of attention from scholars, and the design of the experimental platform for different working conditions is a key research area. Starting from the actual needs, the magnetic property measurement method of grain-oriented silicon steel can be roughly divided into the DC measurement method and AC measurement method, and each method can be divided into one-dimensional, two-dimensional, and three-dimensional measurement methods according to consideration of the anisotropy and measurement dimension. Due to the actual service of power transformers, more reflect the AC magnetic properties, and orientation of silicon steel according to rolling direction permeability is much more prominent than the non-rolling direction; that is, the magnetic circuit is mainly along the rolling direction. Therefore, this paper only considers a one-dimensional AC magnetic property measurement method. Presently, the international standard methods are the Epstein test method [6], the single sheet test method [7] and the ring-sample test method [8]. For experimental measurements using the ring-sample test method, the sample is made into a rectangular ring or two opposing \"C\"-shaped samples with a rectangular cross-section, as shown in Figure 6. Because of the different lengths of the inner and outer diameters of the ring samples, the lengths of the magnetic circuits are also different, so the values measured by the ring-sample test method are average values. The ring-sample test method also needs to use ring-shaped samples according to the actual situation of their own winding, applying the appropriate excitation signal, respectively, in the primary and secondary windings measured in the \(\mathbf{H}\) and \(\mathbf{B}\) signals, so as to obtain the magnetic hysteresis line under AC excitation and the various magnetic properties of the parameters. Among the three methods, the ring-sample test method has the advantages of simple principle and convenient design, and it is suitable laboratory tests. The ring-sample test method can meet the experimental needs of this paper. Therefore, this paper is based on the principle of the ring-sample test method to carry out the design and construction of the magnetic characteristic platform applicable to grain-oriented silicon steel under  
Figure 6: The ring-sample test setup. Before measurement, based on the relevant information about the saturation magnetic induction strength and corresponding magnetic field strength, and after estimation and calculation, 10 turns were selected as the winding turns of grain-oriented silicon steel and evenly wound on the ring sample. In order to reduce the impact of magnetic leakage during measurement on the measurement results, the primary excitation winding and the secondary induction winding were selected, with the same number of turns for winding. In order to solve the problems of excessive winding loss and high internal temperature during the measurement process, enameled wire was selected for winding. The simulator used for the measurement system built in this article is the LabVIEW2018 programming platform developed by the NI Company in the Austin, TX, USA; thus, the data acquisition card uses the latest high-speed acquisition card NI-USB\(-\)6363, provided by the NI Company. In the graphical development environment of NI LabVIEW, there is no need to write lines of text code; rather, a data collection system is developed through drag and drop icons.