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The design of electrical machines and magnetic actuators require accurate models to represent hysteresis effects in ferromagnetic materials. The magnetic nonlinearity of the iron core is usually considered by an anhysteretic magnetization curve. With this assumption, hysteresis effects in the field computation are completely neglected. This paper presents a comparative study of different hysteresis models, particularly Pragmatic Algebraic Model (PAM) and vector stop model, with regard to a vector anhysteretic anisotropic model. The PAM turns out to be an efficient model considering eddy currents effect. The multi cells stop model relies on a consistent thermodynamic formulation, whose dissipation corresponds to a dry friction-like element. Both models implement a constitutive relationship, in which the magnetic flux density vector as independent input and magnetic eld strength as output. This relationship allows integrating directly in FE with vector magnetic potential formulation. With a rotational single sheet tester (RSST), various tests for a sample of material FeSi24-50A (FeSi) with a silicon proportion of 2.4 wt% can be proceeded under the application of relevant eld distribution. The obtained measured data are applied to parameterize and validate the models. Following numerical experiments the results are compared with those obtained by means of an anhysteretic anisotropic model.

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Demagnetization characteristics of permanent magnets play a central role for the design and optimization process of permanent magnet electrical machines and magnetic actuators. Currently, practical issues, such as loss of performance of electromagnetic energy conversion devices, due to demagnetization effects in permanent magnets or due to reduced servo‐dynamics in magnetic actuators, cannot be addressed by using conventional material models or are investigated by using rough approximations valid in restricted operation regions, if at all. This paper strives to integrate demagnetizing characteristics dependent on previous magnetizing field strength in the finite element method. The discussed examples are a magnetizer of a single permanent magnet and a spoke‐type permanent magnet rotor.