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Magnetic recording
Published in David Jiles, Introduction to the Electronic Properties of Materials, 2017
The essential idea of the Preisach model is that the observed bulk magnetic hysteresis loop of a material is due to a summation of more elementary hysteresis loops of domains with differing switching fields (coercivities). These ‘pseudodomains’ can only have two states within the confines of the model, with magnetization parallel or antiparallel to a given direction. The model relies on a density function called the Preisach function which is defined on a plane described by the positive and negative switching fields H+ and H−. This function is used to determine how many domains switch their orientation from + to −, or vice versa, as the field is swept between limiting values of magnetic field H.
Magnetic Recording
Published in David Jiles, Introduction to Magnetism and Magnetic Materials, 2015
The essential idea of the Preisach model is that the measured magnetic hysteresis loop of a material is due to a summation of more elementary hysteresis loops of domains with differing switching fields. Within the confines of the model, these domains can only have two states, with magnetization parallel or antiparallel to a given direction. The model relies on a density function called the Preisach function, which is defined on a plane described by the positive and negative switching fields H+ and H−. This Preisach function is used to determine how many domains switch their orientation from + to −, or vice versa, as the applied magnetic field is swept between extreme values.
Methods of Investigation and Constructional Materials
Published in Janusz Turowski, Marek Turowski, Engineering Electrodynamics, 2017
Janusz Turowski, Marek Turowski
One of the best known methods of a mathematic description of the complicated magnetization processes is the Preisach model of hysteresis from 1935 (published in Zeitschrift für Physik, 1938) in which a ferromagnetic material is represented as a collection of small elementary domains (hysterons) with parallel-connected rectangular hysteresis loops (Figure 1.20a, right). Each hysterons is magnetized to a value of either h or −h. They interact with each other and create a stepped graph with accuracy, depending on the number of elementary loops, N. The Preisach model has been followed and improved by other researchers too (e.g., Atherton [1.28]).
Modelling of piezoelectric actuating systems subjected to variable loads and frequencies and applications to prescribed performance control
Published in International Journal of Control, 2023
Ying Feng, Zedong Hu, Mingwei Liang
For the modelling of piezoelectric actuators, some studies have been conducted focusing on the special hysteresis behaviour with the multi-valued and non-differentiable characteristics (see for instance L. Chen et al., 2019; Tan & Baras, 2005). Some phenomenological hysteresis modelling methods were discussed to show the input-output relationship of hysteresis accurately, including Preisach model (see for instance Song et al., 2016; Tan & Baras, 2005), Prandtl–Ishlinskii (PI) model (see for instance Z. Li et al., 2014). Generally, the delay operator in the classical Preisach model and the play or stop operators in PI model have the rate-independence property, so the rate-dependent feature in the smart material-based actuators is not represented properly using the classical hysteresis model. The extension in the hysteresis modelling to characteristic rate-dependent property is a new difficulty, and some extended presentation methods were proposed to show some special properties in the piezoelectric actuators such as input frequency rate-dependent property (see for instance M. Janaideh et al., 2011; Oh et al., 2009), creep and asymmetric property (see for instance J. Li et al., 2019). Besides, some works were investigated to model hysteresis using different ways (see forY. Liu et al., 2019; Yoong et al., 2021). In the work of Y. Liu et al. (2019), a distributed parameter Maxwell-slip model was used to represent the hysteresis. In the work of Srivastava et al. (2017), both the first-order descending and ascending curves were used and each of these curves was approximated by an artificial neural network (ANN). Since the weights of the ANNs are updated online, the classical Preisach model has been modified to adapt to changes in the operating conditions, and can easily be used to control strain in real-time.