• Title, Summary, Keyword: Hysteresis

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Precision Position Control System of Piezoelectric Actuator Using Inverse Hysteresis Modeling and Error Learning Method (역 히스테리시스 모델링과 오차학습을 이용한 압전구동기의 초정밀 위치제어)

  • 김형석;이수희;정해철;이병룡;안경관
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.383-388
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    • 2004
  • A piezoelectric actuator yields hysteresis effect due to its composed ferroelectric. Hysteresis nonlinearty is neglected when a piezoelectric actuator moves with short stroke. However when it moves with long stroke and high frequency, the hysteresis nonlinearty can not be neglected. The hysteresis nonlinearty of piezoelectric actuator degrades the control performance in precision position control. In this paper, in order to improve the control performance of piezoelectric actuator, an inverse modeling scheme is proposed to compensate the hysteresis nonlinearty problem. And feedforward - feedback controller is proposed to give a good tracking performance. The Feedforward controller is inverse hysteresis model, Nueral network and PID control is used as a feedback controller. To show the feasibility of the proposed controller and hysteresis modeling, some experiments have been carried out. It is concluded that the proposed control scheme gives good tracking performance

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Relation Between Ferroelectric and Piezoelectric Hysteresis Loops (강유전 이력곡선과 압전 이력곡선의 관계)

  • Song, Tae Kwon
    • New Physics: Sae Mulli
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    • v.67 no.7
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    • pp.822-827
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    • 2017
  • Ferroelectric polarization-electric field hysteresis loops and piezoelectric strain-electric field hysteresis loops of ferroelectric materials are systematically compared, especially from the viewpoint of coercive fields. The ferroelectric hysteresis loops were simulated with simple hyperbolic functions by considering linear dielectric responses and non-linear switching responses; the piezoelectric hysteresis loops were simulated with the piezoelectric responses of ferroelectric domains. Then, the simulated hysteresis loops were compared with the experimental hysteresis loops of piezoelectric $BiFeO_3-BaTiO_3$ ceramics. Based on these results, the electric-field-dependent piezoelectric constants d(E) of the samples were calculated.

Measurement of Hysteresis in PZT-Type Tunable Filters Utilizing OFDR (OFDR을 이용한 PZT형 파장가변 필터의 이력 측정)

  • Park, Do-Hyun;Yeh, Yun-Hae
    • Korean Journal of Optics and Photonics
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    • v.19 no.1
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    • pp.36-42
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    • 2008
  • Implementation of a wavelength-swept source with constant tuning rate adopting a PZT-type tunable filter, requires the knowledge of hysteresis of the filter used. The hysteresis must be considered to avoid any degradation in resolution of the optical frequency domain reflectometry (OFDR) system. An optical spectrum analyzer (OSA) could be used to do the hysteresis measurement, but its measurement time is too long for the high-speed driving conditions for the filter. We proposed a new hysteresis measurement method based on OFDR, which could measure the hysteresis in a real driving condition. A hysteresis measurement apparatus consisted of wavelength-swept source, interferometer, signal processing unit, and PC program is built and used to do the measurement. It is concluded that the new method is useful in the measurement of hysteresis at real driving conditions by successfully implementing a swept-wavelength source whose wavelength change is linear in time.

Operation of Brushless DC Motor using the Adaptive hysteresis bandwidth control algorithm (적응 Hysteresis band폭 제어 알고리즘을 이용한 Brushless DC Motor의 운전)

  • Cho, Kye-Seok;Kim, Kwang-Yeon;Hyun, Dong-Seok
    • Proceedings of the KIEE Conference
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    • pp.171-174
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    • 1991
  • Among the various PWM methods, the hysteresis-band current control PWM method is popularly used because of its simplicity of implementation, fast response characteristics and inherent peak current limiting capability. However, the current control PWM method with a fixed hysteresis-band has the disadvantage that switching frequency decreases and current ripple is high as the increasing of back-EMF. As a result, load current contains excess harmonics. This paper describes a adaptive hysteresis-bandwidth control algorithm so as to maintain the average switching frequency constant and decrease the current ripple where the hysteresis bandwidth is derived as a relation with the switching frequency. This control algorithm is applied to the surface-type brushless DC motor with separated winding and using the computer simulation, the validity of its algorithm is proved.

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Comparative Study of Non-Electrochemical Hysteresis Models for LiFePO4/Graphite Batteries

  • Ma, Jiachen;Xie, Jiale;Bai, Kun
    • Journal of Power Electronics
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    • v.18 no.5
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    • pp.1585-1594
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    • 2018
  • The estimation of $LiFePO_4$/graphite battery states suffers from the prominent hysteresis phenomenon between the respective open-circuit voltage curves towards charging and discharging. A lot of hysteresis models have been documented to investigate the hysteresis mechanism. This paper reviews and deeply interprets four non-electrochemical hysteresis models and some improvements. These models can be conveniently incorporated into commonly used equivalent circuit models to reproduce battery behaviors. Through simulation and experimental comparisons of voltage predictions and state-of-charge estimations, the pros and cons of these models are presented.

A Double Band Hysteresis Current Control Method (이중밴드 히스테리시스 전류 제어 방식)

  • Oh W.H.;Yoo C.H.;Shin E.C.;Park S.M.;Noh H.Y.;Yoo J.Y.
    • Proceedings of the KIPE Conference
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    • pp.579-583
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    • 2003
  • Hysteresis controllers are intrinsically robust to system parameters, exhibit very high dynamic response and are suitable for simple implementation. But the current control using a conventional hysteresis controller has the disadvantage that high switching frequency may happen due to lack of coordination among individual hysteresis controllers of three phases. This will of course increase the switching loss. In addition, the current error is not strictly limited. So, in this paper to reduce the switching frequency, a double band hysteresis current controller is proposed. The presented control system was tested with digital simulation in the Borland C++ program and demonstrate the advantage of proposed hysteresis current controller.

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Effect of Temperatrue on Sorption Hysteresis of Short Grain-Rough Rice (온도가 단립종벼의 Hysteresis에 미치는 영향)

  • 신명곤;김동철;민봉기;최홍식
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.20 no.3
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    • pp.281-283
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    • 1991
  • The effect of temperature on hysteresis of rough rice grown in Korea was investigated. The maximum hysteresis effect of Chucheongbyeo paddy rice at 5$^{\circ}C$ amounted to an average 1.7% moisure content. However, their values at $25^{\circ}C$ and 4$0^{\circ}C$ averaged 1.2% and 0.7% moisture, respectively. It may be suggested that the exteents of hysteresis are affected by the temperature of hysteresis are affected by the temperature of adsorption and desorption.

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Hysteresis Investigation of Magnetorheological Fluid Using Preisach Model (Preisach모델을 이용한 MR 유체의 히스테리시스 특성 고찰)

  • Han, Y.M.;Lim, K.H.;Choi, S.B.
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.16 no.1
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    • pp.3-11
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    • 2006
  • This paper presents a new approach for hysteresis modeling of a magnetorheological (MR) fluid. The field-dependent hysteresis of MR fluid is investigated using the Preisach model. The commercial MR product (MRF-132LD, Lord Corporation) is employed. Its field-dependent shear stress is then obtained using a rheometer (MCR 300, Physica). In order to show the applicability of the Preisach model to the MR fluid, two significant properties; the minor loop property and the wiping-out. property are experimentally examined. Subsequently, the Preisach model for the MR fluid is identified using experimental first order descending (FOD) curves in discrete manner. The effectiveness of the identified hysteresis model is verified in the time domain by comparing the predicted field-dependent shear stress with the measured one. In addition, the hysteresis model proposed in this work is compared to Bingham model.

Low Hysteresis Organic Thin Film Transistors with Modified Photocrosslinkable Poly (4-vinylphenol)

  • Kim, Doo-Hyun;Kim, Hyoung-Jin;Kim, Byung-Uk;Kim, We-Yong;Kim, Ho-Jin;Hong, Mun-Pyo
    • 한국정보디스플레이학회:학술대회논문집
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    • pp.563-565
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    • 2009
  • We introduce the new modification approaches of photocrosslinkable poly (4-vinylphenol) (PVP) for low hysteresis organic thin film transistors (OTFTs). The dielectric layers were composed of different PVP resin, low molecular melamine, and halogen free photo-initiator. The low hysteresis OTFT from one of the organic gate dielectrics has been realized. The electrical performance of low hysteresis OTFT with photocrosslinkable PVP exhibited a field-effect mobility of 0.2 cm2/Vs, a threshold voltage of - 0.04V, hysteresis of 0.4V.

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Improved E&S Vector Hysteresis Model for the Precise Modeling of Vector Magnetic Properties of Electrical Steel Sheet (전기강판의 벡터 자기특성 모델링을 위한 개선된 E&S Vector Hysteresis Model)

  • Song, Min-Ho;Yoon, Hee-Sung;Koh, Chang-Seop
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.9
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    • pp.1684-1692
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    • 2011
  • Recently, several vector hysteresis models such as vector Preisach, vector Jiles-Atherton and dynamic E&S model have been proposed to describe vector magnetic properties of electrical steel sheets. However, it is still difficult to find an adequate vector hysteresis model in finite element application for both the Non-oriented and Grain-oriented electrical steel sheets under alternating and rotating field conditions. In this paper, an improved E&S vector hysteresis model is suggested to describe the vector magnetic properties of both Non-oriented and Grain-oriented electrical steel sheets under various magnetic field conditions including alternating and rotating magnetic field conditions. The validity of the proposed model is tested through comparisons with the experimental results under various magnetic field conditions.