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Hysteresis models can incorporate the effects of operating conditions (frequency, stress, and temperature) on iron losses incurred in ferromagnetic materials. Among such models, the Jiles–Atherton (JA) and Preisach models are the most popular and various modifications of these have been proposed in the literature to model the effect of frequency, stress, and temperature on iron losses. Both of these representations produce accurate results compared with the curve fitting models and can be directly implemented in finite element simulations. Unfortunately, it is very difficult to incorporate all these effects into a single iron loss model that is computationally efficient and can predict iron losses with reasonable accuracy for a given range of these parameters. In this paper, an effort has been made to establish a relationship between JA and Preisach models and an interpolation-based approach is presented to predict iron losses that utilizes the Preisach model on top of the JA model and incorporates all of the above factors. It is shown that iron loss can be predicted accurately for any value of frequency, stress, and temperature. [ABSTRACT FROM PUBLISHER]

The paper presents a method for the estimation of the iron losses under PWM (Pulse Width Modulation) flux supply conditions. The computational results are validated versus measurements on Epstein's yoke. The proposed model is based on Finite Element method formulated in the harmonic domain and takes into account ferromagnetic hysteresis and eddy currents. A classical Preisach model is used for hysteresis modelling neglecting the effects of excess losses in field analysis. Different PWM supply conditions are measured and simulated with satisfactory agreement. [ABSTRACT FROM PUBLISHER]

Effect of hysteresis, eddy-current and excess-loss modeling on the 2-D field solution of 12.5-MW and 150-kVA wound-field synchronous machines is studied. The study is performed by comparing the differences in the solutions obtained with three different finite element formulations: one with iron losses fully included, one using only single-valued material properties, and one completely neglecting the iron losses from the solution. The electrical operating points, i.e., the terminal currents and powers are found to be only little influenced by the iron-loss model. However, the rotor eddy-current losses are found to be overestimated, if the skin effect of the eddy currents is uncoupled from the solution. Using single-valued material properties instead of hysteretic ones has a smaller effect on the rotor side, but increases the hysteresis losses in the stator. The effects on the total core losses thus depend on their distribution between the stator and the rotor. It is concluded that using single-valued material properties is reasonable in order to improve the computational performance despite the slight overestimation in the computed core losses. However, for accurate modeling of the rotor losses, the skin effect of the eddy currents should be included in the solution. [ABSTRACT FROM PUBLISHER]