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Accurate magnetic properties measurement of the silicon steel plays an increasingly important role in electromagnetic devices design and optimization. However, with the 2D circular and elliptical magnetization, which usually exist in the corner joint of three-phase transformer and behind the teeth of AC rotating machines, there is lack of experimental data result in the difficulty of reaching high frequency induction at kilohertz range. In this paper, a novel two-dimensional (2-D) magnetic tester with ultra-thin silicon steel sheets is designed and analyzed. In order to improve the measurement precision, a combined B-H sensing structure is designed to avoid the local inhomogeneity of magnetic field distribution caused by drilling holes. Both the alternating and 2D rotating magnetic properties of non-oriented silicon steel M210-35A are systematically measured at a wide range of frequency and magnetic flux density. [ABSTRACT FROM AUTHOR]

There has been an increasing awareness of research on magnetic properties of soft magnetic materials. In reality, the soft magnetic materials are likely to be magnetized by 2-D rotating magnetic field. Moreover, the magnetic properties could be influenced by mechanical stress. In order to investigate the magnetic properties thoroughly, numerous measurement apparatuses have been developed, which could take rotating magnetic flux or mechanical stress into account. However, there is limited research on the investigation of 2-D magnetic properties affected by laminated direction mechanical stress, as few mature devices could be employed, since the traditional $B$ – $H$ sensing coils are easily damaged by laminated direction stress. Therefore, the sensing structure with cubic specimen is proposed for 2-D magnetic properties measurement considering laminated direction stress. The printed circuit board (PCB)-based $B$ – $H$ sensing coils, which are attached to the surrounding surface of the cubic specimen, could be free of the impact of the $z$ -direction mechanical stress. The accuracy of $B$ – $H$ sensing part is analyzed in detail by means of the finite-element method as well as experiments. And, more remarkable, the deficiency of the artificial $H$ -coils wound by enameled wire is presented. Hence, a modified $H$ -coil made of four layer PCBs is proposed in this paper, the measurement accuracy is proven through experiments. [ABSTRACT FROM AUTHOR]

Although two-dimensional (2-D) magnetic properties can be measured by using a 2-D single sheet tester (SST), the construction of the reliable 2-D SST is considerably difficult. By contrast, the flux density and magnetic field parallel to the excitation direction can be measured in a normal one-dimensional (1-D) SST. If the average flux density points toward the excitation direction in a specimen with any inclination angle from its rolling direction, the magnetic energy can be defined and therefore 2-D magnetic properties can be calculated by means of an energy-based modelling method. However, the direction of the flux density and magnetic field in the 1-D SST has not been deeply discussed when a specimen with any inclination angle is measured. In this paper, the behavior of the flux density and the magnetic field strength is examined by using 1-D SST. The direction of the flux density is measured by using a pair of cross B-coils. The direction of the magnetic field strength is measured by using a pair of cross H-coils. The effect of the specimen width on the distribution of flux density is also investigated by using a magnetic field analysis. As a result, when a pair of cross H-coils is adopted to a specimen with appropriate aspect ratio, 2-D magnetic properties can be measured by means of the 1-D SST. [ABSTRACT FROM AUTHOR]

Evaluating magnetic properties accurately under various flux conditions is necessary to reduce iron losses in designing motors and transformers. Particularly, two-dimensional (2-D) magnetic property is one of the most important factors for highly efficient electrical machines. In order to evaluate 2-D magnetic properties of electrical steel sheets, several types of 2-D single sheet testers (2-D SSTs) have been proposed. The structure of magnetizing yoke and coils in a 2-D SST is more complex than an SST for measuring one-dimensional (1-D) magnetic properties of electrical steel sheets (1-D SST). Therefore, leakage inductance of a 2-D SST is generally much larger than that of a 1-D SST, which results in the fact that it is very difficult to measure magnetic properties up to high flux density region with a 2-D SST. In this paper, a round rotational 2-D SST (RRSST) is developed based on motor stator core. The RRSST is compared with the 2-D SST using a square specimen (SRSST) from the standpoint of 2-D magnetic measurement in high flux density region under rotational and alternating flux conditions. [ABSTRACT FROM AUTHOR]

This paper investigates a modeling method of 2-D magnetic properties based on magnetic energy. To verify the effectiveness, finite element analyses of a ring core by the proposed and other modeling methods of magnetic anisotropy are performed and their advantages and disadvantages are discussed from the standpoints of computational accuracy and cost. In addition, we investigate the influence of magnetic anisotropy on the machine performance of synchronous machines. [ABSTRACT FROM AUTHOR]

In order to analyze magnetic characteristics of magnetic devices, it is necessary to accurately measure magnetic properties of an electrical steel sheet in arbitrary directions. In this paper, we developed a 2-D-single-sheet tester (SST) using diagonal exiting coils in order to improve the measurement accuracy under high flux condition. The measurement region of flux density B and magnetic-field strength H is examined for the accurate measurement. The magnetic properties of grain-oriented electrical steel sheet under alternating magnetic flux and rotating magnetic flux are measured using our system. The accuracy of measurement in the case of grain-oriented sheet is examined by comparing the measured results using 2-D-SST with those by using an ordinary SST under alternating flux excitation. The effect of positioning error of orthogonal B and H coils on measurement accuracy is also discussed. [ABSTRACT FROM AUTHOR]