• Title, Summary, Keyword: Hysteresis

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A Study on the Factors Influencing the Abnormal Vibration of the Lateral Direction in Railway Vehicles Caused by Hysteresis of Critical Speed (임계속도 이력현상에 의한 철도차량 횡방향 이상 진동에 영향을 미치는 인자들에 관한 연구)

  • 정우진;심재경;조동현
    • Journal of KSNVE
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    • v.11 no.2
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    • pp.265-275
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    • 2001
  • This research has been performed to reveal the hysteresis phenomena of the hunting motion in a railway passenger cars. It is found that there are some factors and its operation region to make the nonlinear critical speed reacts to them more sensitively than the linear critical speed. The simulation results show that a self steering bogie system can be a substitute proposal to improve curving Performance together with the reduction of hysteresis of critical speed. Full scale roller rig test is carried out for the validation of the numerical results. Finally, it is certified that wear of wheel profile and stiffness discontinuities of wheelset suspension caused by deterioration have to be considered in the analysis to predict the hysteresis of critical speed precisely.

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Modeling and Motion Control of Piezoelectric Actuator (비선형성을 고려한 압전소자의 모델링 및 운동제어)

  • 박은철;김영식;김인수
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • pp.630-637
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    • 2003
  • This paper proposes a new modeling scheme to describe the hysteresis and the dynamic characteristics of piezoelectric actuators in the inchworm and develops a control algorithm for the precision motion control. From the analysis of piezoelectric actuator behaviors, the hysteresis can be described by the functions of a maximum input voltage. The dynamic characteristics are also identified by the frequency domain modeling technique based on the experimental data. For the motion control, the hysteresis behavior is compensated by the inverse hysteresis model. The dynamic stiffness of an inchworm is generally low compared to its driving condition, so mechanical vibration may degenerate the motion accuracy of the inchworm. Therefore, the sliding mode control and the Kalman filter are developed for the precision motion control of the inch-warm. To demonstrate the effectiveness of the proposed modeling schemes and control algorithm, experiment validations are performed.

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Adaptive Hysteresis Band Current Control Independent of the Back EMFs (역기전력에 무관한 가변 히스테리시스 밴드 전류 제어)

  • Kim, Kyeong-Hwa;Cho, Kwan-Yuhl;Chung, Se-Kyo;Oh, Dong-Seong;Youn, Myung-Joong
    • Proceedings of the KIEE Conference
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    • pp.1172-1175
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    • 1992
  • The conventional adaptive hysteresis band current control technique has disadvantages such that on-line calculation of the hysteresis band is very complex, therefore, the adaptive hysteresis band must be stored in the look-up table. In this paper, a new simplified adaptive hysteresis band current control technique with phase decoupling is presented. The adaptive band is independent of the back EMFs. Using this adaptive band and the phase decoupled current error, the modulation frequency is fixed at nearly constant and the PWM inverter has optimal switching pattern.

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A Magnetic Circuit Model of Inductive Sensor Considering Eddy Currents and Hysteresis (와전류와 히스테리시스를 고려한 유도형 변위 센서의 자기회로 모델 개발)

  • 노명규;정민경;박병철
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.267-270
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    • 2002
  • The accuracy and the dynamic bandwidth are the two most important indices that an inductive position sensor is evaluated with. Eddy currents and magnetic hysteresis affect both of these performance indices. As the modulation frequency of the sensor increases to improve the dynamic bandwidth, the effects of eddy currents and hysteresis also increases, which results in the loss of accuracy. In this paper, a magnetic circuit model of the differential inductive sensor is developed. This model includes the effects of hysteresis and eddy currents. Experimental results confirm the validity of the model. The model predicts that the eddy current effects are not significant below the modulation frequency of 50kHz, as long as the lamination thickness is adequate.

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Hysteresis Compensation Control of Piezoelectric Actuators (피에조일렉트릭 액츄에이터의 히스테리시스 보상 제어)

  • 임요안;최기흥;최기상
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.219-224
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    • 1996
  • Piezoelectric actuators exhibit limited accuracy in tracking control due to their hysteresis nonlinearity. In this study a digital tracking control approach for a piezoelectric actuator based on incorporating a feedback linearization loop with a PID feedback controller is presented. The hysteresis nonlinearity of the piezoelectric actuator is modeled in the feedback compensation loop using the Maxwell slip model. Experiments were performed on a piezoelectric 2-axis linear positioner for tracking linearly decaying sinusoidal waveforms and circles. The experimental results show that the tracking control performance is noticeably improved by augmenting the feedback loop with a model of hysteresis in the feedback compensation loop.

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Precision Control of a Piezoelectric Actuator Based on an Inverse Hysteresis Model (역 히스테리시스 모델에 기초한 압전 구동기의 정밀제어)

  • Park, Seung-Man;Ahn, Hyun-Sik;Kim, Do-Hyun;Song, Joong-Ho;Choy, Ick;Kim, Kwang-Bae
    • Proceedings of the KIEE Conference
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    • pp.2368-2370
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    • 2000
  • In this paper, we proposed an inverse hysteresis model to cancel the nonlinear hysteresis phenomenon of a piezoelectric actuator and design a feedback control system based on the inverse hysteresis model. The piezoelectric actuator performs much better in open-loop response. However, the nonlinear hysteresis phenomenon should be linearized and the closed-loop control should be executed to get the required performance in the area, where high-speed and high-accuracy are required. Thus, it is shown by simulation that a good position tracking performance can be obtained for the repetitive desired position trajectory.

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Hysteresis Current Control with Self-Locked Frequency Limiter for VSI Control (자기동조 주파수 제한기를 갖는 전압원 인버터의 히스테리시스 전류제어)

  • Choe, Yeon-Ho;Im, Seong-Un;Gwon, U-Hyeon
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.51 no.1
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    • pp.23-33
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    • 2002
  • A hysteresis control is widely used to control output current of inverter. A hysteresis bandwidth is affected by system parameters such as source voltage, device on/off time, load inductance and resistance. The frequency limiter is used to protect switching devices overload. In the conventional hysteresis controller, a lock-out circuit with D-latch and timer is used to device protection circuit. But switching delay time and harmonic components are appeared in output current. In this paper the performance of lock-out circuit is tested, and new circuit for switching device fault protection is proposed ad it's performance is simulated.

Analysis on Hysteresis Characteristics of Flux-Lock Type HTSC Fault Current Limiter (자속구속형 고온초전도 사고전류 제한기의 히스테리시스 특성 분석)

  • Lim, Sung-Hun;Han, Byoung-Sung;Park, Hyoung-Min;Cho, Yong-Sun;Han, Tae-Hee;Do, Ho-Ik;Choi, Hyo-Sang
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • pp.493-495
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    • 2006
  • The hysteresis characteristics of flux-lock reactor, which is an essential component of flux-lock type superconducting fault current limiter (SFCL), was investigated. The hysteresis loss of iron core in flux-lock type SFCL does not happen due to its winding's structure especially in the normal state. From the equivalent circuit for the flux-lock type SFCL and the fault current limiting experiments, the hysteresis curves could be drawn. Through the hysteresis curves together with the fault current level due to the inductance ratio 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.

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A Study on the Method of Giving Hysteresis Characteristics to the Digital input port of Microprocessors (마이크로프로세서 디지털 입력포트에 대한 히스테리시스 특성 부여방법에 관한 연구)

  • Lee, Hyun-Chang
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.2
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    • pp.56-63
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    • 2011
  • This paper presents the method of giving hysteresis characteristics to the digital input port of microprocessors or micro-controllers and it's design procedures. And this paper shows the example of circuit design and the effect of this method by experiments. Presented method has advantages : By the additional one port and two resistors, input port can have hysteresis characteristics and hysteresis band is larger than TTL, CMOS schmitt trigger gates.

Analysis on Hysteresis Characteristics of a Transformer Type Superconducting Fault Current Limiter (변압기형 초전도전류제한기의 히스테리시스 특성 분석)

  • Lim, Sung-Hun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.2
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    • pp.164-168
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    • 2010
  • The transformer is expected to be an essential component of a superconducting fault current limiter (SFCL) for both the increase of its voltage ratings and the simultaneous quench due to different critical current between high-$T_C$ superconducting (HTSC) elements comprising the SFCL. However, in order to perform the effective current limiting operation of the SFCL, the design for the SFCL considering the hysteresis characteristics of the iron core is required. In this paper, the influence of the hysteresis characteristics of the iron core comprising the transformer type SFCL on its current limiting characteristics was investigated. Through the comparative analysis on the hysteresis curves due to the ratio of the turn number between the 1st and the 2nd windings of the transformer, the proper design condition for the ratio of the turn number to achieve the effective current limiting operation of the transformer type SFCL could be obtained.