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Preisach-type models are suggested for the description of strain hysteresis of magnetostrictive materials. It is pointed out that the strain hysteresis has some peculiar properties in comparison with magnetic hysteresis. These peculiarities of strain hysteresis are discussed in detail along with the identification problem for these models.

Abstroct-Magnetostrictivematerials a r e known to have hysteresis with respect to both magnetic field H and mechanical stress 6. Also, the order in which H and (T are applied is sometimes significant. This paper proposes one generalization of the classical Preisach model in which these properties are handled by treating a combination of H and 6 as an effective field H e (H ,o). The classical Preisach model can thus be generalized to M ( t ) = II p(a,p) rap H, (~( t ) , o ( t ) , a ,~) d a d~ -H , S f k a l H , I H e also depends on a and p. In this paper, the function H e (H ,o,a,p) will be assumed to have a certain simple form. I t Is shown that all necessary parameters can then be determined from a comparatively small number of experiments and that the above expression can be reduced to a single integral. T o test the validity of the model , experiments where the two components H and d have been varied in many different ways have been performed on Terfenol-D and compared to results computed from the model. Some of these results are presented in the paper.This stress-dependent model is found to have an accuracy comparable to that of the classical Preisach model.

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4~4.simct-A C a u e r circuit model of a transformer lami n a t e is presented. It considers saturation, e d d y currents a n d hysteresis. T h e simulation results agree t o experiments with a n Epstein f r a m e in t h e 10-200 Hz range. T h e p a p e r includes a description of a computationally fast hysteresis model with few adjustable p a r a m e t e r s a n d a physical approach to derive t h e C a u e r circuit. T h e model can b e used u n d e r various time-transient conditions a n d can easily b e implemented into a larger system in a circuit simulation package, such as S a b e r , t o s t u d y a transformers interaction with switching overvoltages, for example.

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