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This paper presents a modified Mayergoyz-based vector hysteresis model to describe the anisotropic material behavior of nonoriented (NO) steels over a wide range of rotational excitations. The proposed model adopts a new representation of a vector Everett function, which is actually an elliptical interpolation motivated by the real anisotropic behavior of NO steel, to deal with the uniaxial anisotropy characteristic, which is especially pronounced at low induction levels. The biaxial anisotropy occurring at high densities is described by a nonlinear coefficient, which is actually a function of the magnitude of magnetic flux density. A systematic identification algorithm is given in detail. The validity of this model is verified through comparison with experimental data under both alternating and rotational excitations. The 2-D finite element analysis (FEA) of incorporating this model into TEAM problem 32 simulation is also illustrated. [ABSTRACT FROM AUTHOR]

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]

• A single-sheet tester to measure electrical steel loss under uniaxial magnetisation. • Transverse magnetisation is shown to occur in grain-oriented silicon steel. • Losses due to transverse fields are not detected in conventional test methods. • Transverse losses depend on grain size and mis- orientation in grain oriented steel. • Transverse loss is not normally of practical importance in electrical machine cores. A modified rotational single-sheet tester, in which a circular sample can be rotated to be magnetised along arbitrary directions, was used to study the transverse magnetisation and associated losses in grain-oriented electrical steel (GOES). Longitudinal and transverse components of flux density B and magnetic field H in a sample of commercial GOES were measured under alternating excitation at angles from −90° to +90° to the rolling direction (RD) at peak flux densities up to 1.5 T over a magnetising frequency range of 20–400 Hz. The loss due to the transverse components of B and H, referred to as the transverse loss, was evaluated. At 1.5 T, 20 Hz, the transverse loss was less than 0.1 mW/kg when magnetised along either the RD or the transverse direction but it rose to around 5 mW/kg when magnetised at 30° to the RD. It was found to be magnetising direction, frequency and flux density dependent. The transverse loss was a simple function of the angle of magnetisation with respect to the RD but it differed when magnetised along directions on either side of to the RD dependent on the grain structure in the measurement region. The basic phenomenon is explained with the aid of simple magnetic domain and magnetisation models. The difficulty of quantifying its absolute effect in GOES and non-oriented electrical steel is discussed. It appears that transverse magnetisation in GOES is not normally large enough to have any practical effect on measurements obtained using IEC Standard loss testers or on the prediction of electrical machine core losses. A preliminary series of tests showed that transverse loss also occurs in non-oriented electrical steel but it is difficult to quantify. [ABSTRACT FROM AUTHOR]