• Journal of the Korean Magnetics Society
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• v.21 no.1
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• pp.15-22
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• 2011

It is necessary to describe the hysteresis characteristics of magnetic material precisely for the analysis or design of system with ferromagnetic materials. Although Preisach model is regarded as the most accurate method to describe the hysteresis characteristics, it is not widely applied to the real systems because of some difficulties. The conventional Preisach model shows the numerical instabilities during the iterative computations because the density distribution obtained from the sets of M-H curves are strongly localized. To remove such numerical instabilities, M-B instead of M-H is adopted as an implementation variable in normal Preisach modeling. The two dimensional computations with hysteresis characteristics by using normal Preisach modeling are tested and the result showed that the modeling by using M-B variables showed better stabilities than M-H variables.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05a
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• pp.92-97
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• 2002

자성체의 물성적인 성질에 바탕을 둔 Preisach 모델링은 히스테리시스 현상을 수치모사 하기 위한 방법으로 뛰어난 결과를 보여왔다. 하지만 Preisach 모델링은 그 계산과정에서 수렴의 어려움이 존재해 결과 값을 계산하지 못하는 경우가 발생하는 문제를 발생시켜왔었다. 본 논문에서는 Preisach 모델링을 프로그램하는데 있어서 기존에 발생했던 수렴의 문제점과 그 문제점을 해결하기 위한 보다 낳은 프로그램 기법들을 제시하였다. 이 방법은 기존 모델링 기법과 유사한 메모리를 사용하면서 수렴에 있어 향상된 결과를 얻을 수 있었다. 또한 Preisach 모델러를 개발하는 과정에 발생하는 Tracing 모델들을 도식화하여 Preisach 모델링에 대한 이해를 돕고자 하였다.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.876-878
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• 2002

자성체의 물성적인 성질에 바탕을 둔 Preisach 모델링은 히스테리시스 현상을 수치모사하기 위한 방법으로 널리 사용되어 왔다. 히스테리시스 곡선에서 각형비(Squareness)가 큰 경우에 Preisach 밀도가 집중되게 되면 이 근방에 수렴값이 존재할 경우 수렴이 어려워지는 문제가 있다. 본 논문에서는 Preisach 모델링을 프로그램하는데 있어서 기존에 발생했던 수렴의 문제점과 그 문제점을 해결하기 위한 보다 낳은 프로그램 기법들을 제시하였다. 이 방법은 기존 모델링 기법과 유사한 메모리를 사용하면서 수렴에 있어 향상된 결과를 얻을 수 있었다.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.1
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• pp.31-40
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• 2008

This paper presented the development and real-time control of a magnetostrictive micro actuator. Magnetostrictive material has many advantages such as high response time, precision displacement and powerful output force. But Magnetostrictive material has characteristic of hysteresis. Conventional Preisach model which based on experimental data is not suitable to the real-time control because of controlling a magnetostrictive system by Preisach model costs a lot of calculating time. And, we prove the validity of proposed model through the experimental comparison between the classical Preisach model and the proposed one.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.62-64
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• 1996

Two current approaches for modeling the vector magnetic hysteretic process are the vector Preisach models and those models based on a system of noninteracting pseudo-particles. The pseudo-particles are intended to mimic the average behavior of real media particles. The simplest switching mechanisms of pseudoparticles is the Stoner-Wholfarth model. The Preisach models are quite precise in specifying the experimental input to the models. The vector properties of the Preisach models are, however, inadequate. This is partly because of the questionable assumptions used in coupling the various vector hysteresis components. Also these models do not include reversible magnetization changes. Unlike Preisach counterpart, the Stoner-Wholfarth model is inherently vector in nature. This is because spatial distribution and switching mechanisms are imposed on the system of pseudo-particles, so they come closer to representing the physical reality. The lack of interaction between pseudo-particles exclude the usefulness of the Stoner-Wholfarth model for small fields when the medium is traversing minor loops. The present work is an attempt at combining the advantages of above two models into one composite model, including the effect of particle interaction.

• Journal of the Korean Magnetics Society
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• v.23 no.2
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• pp.54-61
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• 2013

Ferromagnetic material's residual magnetization is remained because of the interaction between domains from external apply field, so the electrical and electronic industry and area of defense development request deperm protocol which makes the residual magnetization to 0. But the deperm protocols which are used theses days are developed by using only experience and experiment, so we have to develop deperm protocol considering hysteresis curve. In this paper, Anhysteretic Deperm, Deperm-ME, Flash-Deperm were analyzed using two dimensional finite element method and Preisach model that was formulated by property of magnetic materials. From that analysis, the relations between hysteresis curve and deperm variable are compared by analyzing the trace of Preisach plane. Also, an efficient current ratio of deperm protocol, is proposed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.4
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• pp.469-475
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• 2014

This paper deals with the characteristics evaluations of PM magnetization using stator coil in a Post-Assembly Line Start Permanent Magnet Motor (LSPMM) using a coupled Finite Element Method (FEM) and Preisach modeling, which is presented to analyze the magnetic characteristics of permanent magnets. The focus of this paper is the characteristics analysis relative to magnetizing direction and quantity of permanent magnets due to the eddy current occurring in the rotor bar during magnetization of Nd-Fe-B.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.884-885
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• 2011

A great deal of external magnetic variation is required to demagnetize a magnetic material. In order to analyze a demagnetization model, hysteresis is employed and the best numerical analysis technique so far, regarding hysteresis, is Preisach model. In general, Preisach model, however, bears the instability problem with respect to convergence and hence in this paper, a method adopting M-B variables is proposed to solve the problem. In addition, comparison is made between the experimental MTF equipment and the hysteresis modeling technique for the purpose of developing an effective demagnetization protocol.

• Proceedings of the KIEE Conference
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• summer
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• pp.968-970
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• 2004

자성체의 자화 특성을 해석하기 위해서는 자성체가 가지고 있는 포화 현상과 Hysteresis 현상을 고려해 주어야 한다. 하지만 현재 자화 특성 해석에서는 Hysteresis 현상을 무시하고 포화 현상만을 고려한 해석을 진행하거나 Hysteresis의 메이저 루프 특성만을 고려한 비선형 문제 해석만을 사용하고 있다. 하지만 자성체의 Hysteresis 특성은 메이저 루프적 특성 뿐만이 아닌 마이너 루프적인 특성을 가지고 있어 이 두 특성에 따라 많은 자화량적 변화를 가지게 된다. 또한 같은 재료적 특성을 가진 자성체라고 해도 그 형상에 따라 다른 자화 특성 분포를 가지고 있다. 이러한 두가지 특성을 전부 고려한 해석이 되어야 만이 정확한 자화 특성 해석 방법이라고 할 수 있다. 본 논문에서는 이와 같은 멀티브렌치적 특성과 자성체 형상에 따른 특성을 해석하기 위하여 Preisach 모델링을 이용하여 자성체의 형상에 따른 자화적 특성을 해석하는 연구를 진행하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.660-663
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• 2003

This paper proposes a systematic approach for an accurate control of the Terfenol-D actuator taking into account hysteresis, modeled by applying the classical Preisach operator with memory curve. A desired input displacement is calculated by using the hysteresis inverter, which is fed into the actuator. Then the PI compensator corrects the error between the commanded and actual displacements. Experiments with the step responses show that the PI controller settles in 70 ms and the hybrid controller in 20 ms. It means that the concurrent application of two control schemes is effective to control the actuator.