• Title, Summary, Keyword: Hysteresis

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Hysteresis Compensation in Piezoceramic Actuators Through Preisach Model Inversion (Preisach 모델을 이용한 압전액츄에이터 이력 보상)

  • Chung C.Y.;Lee D.H.;Kim H.S.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.1074-1078
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    • 2005
  • In precision positioning applications, such as scanning tunneling microscopy and diamond turning machines [1], it is often required that actuators have nanometer resolution in displacement, high stiffness, and fast frequency response. These requirements are met by the use of piezoceramic actuators. A major limitation of piezoceramic actuators, however, is their lack of accuracy due to hysteresis nonlinearity and drift. The maximum error due to hysteresis can be as much as 10-15% of the path covered if the actuators are run in an open-loop fashion. Hence, the accurate control of piezoceramic actuators requires a control strategy that incorporates some form of compensation for the hysteresis. One approach is to develop an accurate model of the hysteresis and the use the inverse as a compensator. The Preisach model has frequently been employed as a nonlinear model for representing the hysteresis, because it encompasses the basic features of the hysteresis phenomena in a conceptually simple and mathematically elegant way. In this paper, a new numerical inversion scheme of the Preisach model is developed with an aim of compensating hysteresis in piezoceramic actuators. The inversion scheme is implemented using the first-order reversal functions and is presented in a recursive form. The inverted model is then incorporated in an open-loop control strategy that regulates the piezoceramic actuator and compensates for hysteretic effects. Experimental results demonstrate satisfactory regulation of the position of the piezoceramic actuator to the desired trajectories.

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Precision Position Control of Piezoactuator Using Inverse Hysteresis Model and PID control

  • Kim, jung yong;Lee, byung ryong;Yang soon yong;Ahn kyung kwan
    • 제어로봇시스템학회:학술대회논문집
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    • pp.66.3-66
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    • 2001
  • 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 ,and PID control is used ...

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Visualization of Hysteresis Phenomenon of Shock Waves in Supersonic Internal Flow

  • Suryan, Abhilash;Shin, Choon-Sik;Setoguchi, Toshiaki;Kim, Heuy-Dong
    • Journal of the Korean Society of Visualization
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    • v.8 no.2
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    • pp.31-39
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    • 2010
  • Hysteresis is an effect by which the order of previous events influences the order of subsequent events. Hysteresis phenomenon of supersonic internal flows with shock waves has not yet been clarified satisfactorily. In the present study, experiments are carried out on internal flow in a supersonic nozzle to clarify the hysteresis phenomena for the shock waves. Flow visualization is carried out separately on the straight and divergent channels downstream of the nozzle throat section. Results obtained were compared with numerically simulated data. The results confirmed hysteresis phenomenon for shock wave in the Laval nozzle at a certain specific condition. The relationship between hysteresis phenomenon and the range of the rate of change of pressure ratio with time was shown experimentally. The existence of hysteretic behavior in the formation, both the location and strength, of shock wave in the straight part of the supersonic nozzle with a range of pressure ratio has also been confirmed numerically.

Basic study on hysteresis modeling using micromagnetics for magnetic field analysis (미소자성체를 이용한 자기히스테리시스 모델 연구)

  • Cheon, Yeong-Jin;Kim, Jong-Tae;Wee, Sang-Bong
    • Proceedings of the KIEE Conference
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    • pp.83-85
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    • 2007
  • In magnetic field analysis of electrical machines, hysteresis phenomena of B-H curves should be taken into account in order to obtain more accurate results. In this paper, the hysteresis modeling using the micromagnetics for the magnetic field analysis is investigated. In the micromagnetics, usually, it takes much CPU times. Therefore, the method for representing hysteresis phenomena by minimum modeling is investigated in order to applying it to the magnetic field analysis. First, the micromagnetics is described. Then, the method of minimum modeling is shown. Finally, the hysteresis curve obtained by the minimum modeling is demonstrated. The effect of parameters of micromagnetics on the shape of hysteresis curve is investigated.

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Hysteresis Characteristics of Flux-Lock Type Superconducting Fault Current Limiter (자속구속형 고온초전도 사고전류제한기의 히스테리시스 특성)

  • Lim, Sung-Hun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.1
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    • pp.66-70
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    • 2007
  • For the design to prevent the saturation of the iron core and the effective fault current limitation, the analysis for the operation of the flux-lock type superconducting fault current limiter (SFCL) with consideration for the hysteresis characteristics of the iron core is required. In this paper, the hysteresis characteristics of the flux-lock reactor, which is an essential component of the flux-lock type SFCL, were investigated. Under normal condition, the hysteresis loss of the iron core in the flux-lock type SFCL does not happen due to its winding structure. From the equivalent circuit for the flux-lock type SFCL and the fault current limiting experiments, the hysteresis curves could be drawn. From the analysis for both the hysteresis curves and the fault current limiting characteristics due to the number of turns for the 1st and 2nd windings, the increase of the number of turns in the 2nd winding of the flux-lock type SFCL had a role to prevent the iron core from saturation.

Precision Position Control of Piezoelectric Actuator Using Feedforward Hysteresis Compensation and Neural Network (히스테리시스 앞먹임과 신경회로망을 이용한 압전 구동기의 정밀 위치제어)

  • Kim HyoungSeog;Lee Soo Hee;Ahn KyungKwan;Lee ByungRyong
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.7
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    • pp.94-101
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    • 2005
  • This work proposes a new method for describing the hysteresis non-linearity of a piezoelectric actuator. The hysteresis behaviour of piezoelectric actuators, including the minor loop trajectory, are modeled by geometrical relationship between a reference major loop and its minor loops. This hysteresis model is transformed into inverse hysteresis model in order to output compensated voltage with regard to the given input displacement. A feedforward neural network, which is trained by a feedback PID control module, is incorporated to the inverse hysteresis model to compensate unknown dynamics of the piezoelectric system. To show the feasibility of the proposed feedforward-feedback controller, some experiments have been carried out and the tracking performance was compared to that of simple PTD controller.

Hysterersis Compensation in SMA Actuators Through Numerical Inverse Preisach Model Implementation

  • Kha, Nguyen-Bao;Ahn, Kyoung-Kwan
    • 제어로봇시스템학회:학술대회논문집
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    • pp.2048-2053
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    • 2005
  • The aim of this paper is to compensate hysteresis phenomena in Shape Memory Alloy (SMA) actuators by using numerical inverse Preisach model. This is used to design a controller that correct hysteresis effects and improve accuracy for the displacement of SMA actuators. Firstly, hysteresis is identified by numerical Preisach model implementation. The geometrical interpretation from first order transition curves is used for hysteresis modeling. Secondly, the inverse Preisach model is formulated and incorporated in open-loop control system in order to obtain desired input-output relationship with hysteresis reducing. The experimental results for hysteresis compensation by using this method are also shown in this paper.

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Hysteresis characterization and identification of the normalized Bouc-Wen model

  • Li, Zongjing;Shu, Ganping
    • Structural Engineering and Mechanics
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    • v.70 no.2
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    • pp.209-219
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    • 2019
  • By normalizing the internal hysteresis variable and eliminating the redundant parameter, the normalized Bouc-Wen model is considered to be an improved and more reasonable form of the Bouc-Wen model. In order to facilitate application and further research of the normalized Bouc-Wen model, some key aspects of the model need to be uncovered. In this paper, hysteresis characterization of the normalized Bouc-Wen model is first studied with respect to the model parameters, which reveals the influence of each model parameter to the shape of the hysteresis loops. The parameter identification scheme is then proposed based on an improved genetic algorithm (IGA), and verified by experimental test data. It is proved that the proposed method can be an efficacious tool for identification of the model parameters by matching the reconstructed hysteresis loops with the target hysteresis loops. Meanwhile, the IGA is shown to outperform the standard GA. Finally, a simplified identification method is proposed based on parameter sensitivity, which indicates that the efficiency of the identification process can be greatly enhanced while maintaining comparable accuracy if the low-sensitivity parameters are reasonably restricted to narrower ranges.

Hysteresis Characteristics of a-Si:H TFT (비정질 실리콘 박막 트랜지스터 히스테리시스 특성)

  • 이우선;정용호;김남오;김병인;장의구
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.43-46
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    • 1995
  • We fabricate a bottom gate a-Si:H TFT on N-Type <100> Si wafer. According to the variation of gate and drain voltage, the hysteresis characteristic curves were measured experimentally. Also, we showed that the model predict the hysteresis characteristic successfully. Drain current on the hysteresis characteristic currie showed an exponential variation. Hysteresis area of TFT increased with the drain voltage increase and decreases with the drain voltage decrease.

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Mathematical Modeling of Hysteresis Characteristics of a-Si:H TFT (비정질 실리코 박막 트랜지스터 히스테리시스 특성의 수학적인 모델)

  • Lee, Woo-Sun;Kim, Byung-In
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.43 no.7
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    • pp.1135-1143
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    • 1994
  • We fabricate a bottom gate a-Si:H TFT on N-Type <100> Si wafer. According to the Variation of gate and drain voltage, the hysteresis characteristic curves were measured experimentally. Also, we proposed model equation and showed that the model predict the hysteresis characteristic successfully. Drain current on the hysteresis characteristic curve showed an exponential variation. Hysteresis area of TFT increased with the drain voltage increase and decreases with the drain voltage decrease.

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