• Title, Summary, Keyword: Hysteresis

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Characteristic Comparison between PI and Hysteresis Voltage Control of High Voltage Unidirectional Inverter for Piezoelectric Load using FPGA (FPGA를 이용한 피에조 부하 구동용 고전압 단방향 인버터의 PI 및 히스테리시스 전압 제어 특성 비교)

  • Kim, Ki-Seok;Cho, Yong-Ho;Kim, Hyeong-Seop;Kang, Tae-Sam;Hong, Sun-Ki
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.1
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    • pp.48-54
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    • 2017
  • In this paper, hysteresis voltage control method is proposed to an unidirectional inverter control for piezoelectric load. Piezoelectric load has electrically RC characteristic, and is driven by the inverter to control the output voltage waveform. When controling the output waveform by PI control, appropriate gains need to be selected. However, hysteresis control may minimize the output distortion because it has maximum proportional gain. In addition, Hysteresis control algorithm has simple structure to realize and the response is fast. Although the switching frequency of the inverter by hysteresis control varies, the switching frequency for the piezoelectric load is lower than that by PI control for equivalent performance. In particular, on implementing the algorithm using FPGA, the algorithm can be implemented in fewer pabrics and the processing time can be reduced. The superiority of the proposed hysteresis voltage control was proved for piezoelectric load through simulation and experiment.

Hysteresis Reduction in piezoelectric actuator by a charge control method (전하 제어법을 이용한 압전 액추에이터의 이력저감)

  • Jeong Soonjong;Lee Daesu;Song Jaesung;Hong Younpyo;Kang Eungu;Choi Wonjong
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • pp.35-39
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    • 2005
  • This paper presents a method to reduce hysteresis in multilayer ceramic actuator by connecting the actuator with a capacitor in a series circuit. The change in hysteresis with respect to the capacitor was examined. $0.2Pb(Mg_{1/3}Nb_{2/3})O_3-0.8Pb(Zr_{0.475}Ti_{0.525})O_3$ ceramic material was used as a piezoelectric material for the actuator. Displacement of the actuator was measured in a capacitive gap sensor measuring system. In case of inserting a capacitor in a total circuit, hysteresis became dramatically decreased, and then finally the hysteresis value can be reduced below $0.2\%$. It was found in this present study that reducing the hysteresis in the actuator is dependent upon the characteristics of the capacitor in total circuit and also operating frequency.

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A Model of Magnetic Bearings Considering Eddy Currents and Hysteresis

  • Myounggyu Noh
    • International Journal of Precision Engineering and Manufacturing
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    • v.4 no.3
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    • pp.5-11
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    • 2003
  • A simulation model for radial magnetic bearings is presented. The model incorporates hysteresis, saturation and eddy current effects. A simple magnetization model that describes hysteresis and saturation is proposed. Eddy currents are taken into consideration by assuming that they are generated by single-turn fictitious coils wrapped around each magnetic flux path. The dynamic equations describing the simulation model can easily incorporate the operation of switching power amplifier. A simulation of a typical 8-pole radial magnetic bearing produces switching waveforms very similar to the experimental observation.

A Study for Finite Element Analysis of Hysteresis Motor Considering the Rotational Hysteresis in the Ring (링내 회전자계를 고려한 히스테리시스 전동기의 유한요소해석 기법에 관한 연구)

  • Hong, Sun-Ki
    • Proceedings of the KIEE Conference
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    • pp.679-682
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    • 1997
  • This paper presents finite element analysis algorithm combined with vector hysteresis model for accurate analysis of the hysteresis motor. Magnetization-dependent vector model is adapted to calculate the vector magnetization. That is to say, from the magnitude and direction of the magnetic field intensity, the magnetization of each ring element is computed by the vector model. By comparing the simulation results with the experimental ones, it is found that good results are obtained.

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The Simulation of the Characteristics of the Levitation Force in Superconductor Using 2D Slab Model (2차원 Slab 모델을 이용한 초전도체 부상력 특성의 시뮬레이션)

  • 유제환;임윤철
    • Tribology and Lubricants
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    • v.14 no.4
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    • pp.44-50
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    • 1998
  • This paper describes the simulation of the levitation force between permanent magnet and high Tc(critical temperature) superconductor(HTSC). Levitation force is evaluated numerically on the basis of the magnetic vector potential method and the critical state model. The superconductor is approximated to 2-D slab model. By performing computations, the following characteristics have been investigated: the process of the generation of hysteresis, the various hysteretic behaviors. The characteristics of hysteresis are important for the application to magnetic bearing, for the damping and the nonlinear stiffness is related to hysteresis.

An Adaptive Hard Handoff Algorithm for Mobile Cellular Communication Systems

  • Zhu, Huamin;Kwak, Kyung-Sup
    • ETRI Journal
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    • v.28 no.5
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    • pp.676-679
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    • 2006
  • In this letter, we propose an adaptive hard handoff algorithm with a dynamic hysteresis value based on the received signal strength from the serving base station, for mobile cellular communication systems. A discrete-time method is presented to evaluate handoff algorithms analytically. Performance is evaluated in terms of the average number of handoffs, the probability of link degradation, and the average handoff delay. Numerical results and simulations demonstrate that the proposed algorithm outperforms the handoff algorithm with fixed hysteresis values and the handoff algorithm using both threshold and hysteresis.

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Inverse Compensation of Hysteresis in Ferromagnetic Materials (강자성체의 히스테리시스 역 보상 모델)

  • 박영우;한광섭
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.1470-1474
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    • 2004
  • This paper addresses the development of inverse compensation techniques for a class of ferromagnetic transducers including magnetostrictive actuators. In this work, hysteresis is modeled through the domain wall theory originally proposed by Jiles and Atherton[1]. This model is based on the quantification of the energy required to translate domain walls pinned at inclusions in the material with the magnetization at a given field level specified through the solution of an ordinary differential equation. A complementary differential equation is then employed to compute the inverse which can be used to compensate for hysteresis and nonlinear dynamics in control design.

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A Hysteresis Current Controller for PV-Wind Hybrid Source Fed STATCOM System Using Cascaded Multilevel Inverters

  • Palanisamy, R.;Vijayakumar, K.
    • Journal of Electrical Engineering and Technology
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    • v.13 no.1
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    • pp.270-279
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    • 2018
  • This paper elucidates a hysteresis current controller for enhancing the performance of static synchronous compensator (STATCOM) using cascaded H-bridge multilevel inverter. Due to the rising power demand and growing conventional generation costs a new alternative in renewable energy source is gaining popularity and recognition. A five level single phase cascaded multilevel inverter with two separated dc sources, which is energized by photovoltaic - wind hybrid energy source. The voltages across the each dc source is balanced and standardized by the proposed hysteresis current controller. The performance of STATCOM is analyzed by connecting with grid connected system, under the steady state & dynamic state. To reduce the Total Harmonic Distortion (THD) and to improve the output voltage, closed loop hysteresis current control is achieved using PLL and PI controller. The performance of the proposed system is scrutinized through various simulation results using matlab/simulink and hardware results are also verified with simulation results.

Numerical Analysis Unsteady Flow Characteristics of the Wells Turbine (웰즈터빈의 비정상유동특성에 관한 수치해석)

  • 김태훈;박일규;이연원
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • pp.69-74
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    • 2001
  • The Wells turbine has hysteresis characteristics in a reciprocating flow. In this paper, in order to understand unsteady flow characteristics of the Wells turbine, a sinusoidal flow condition is simulated. The flow conditions and hysteresis characteristics, including blade thickness, are investigated over a period of time. The pressure distributions along the blade surface are investigated at mid-span to clarify the cause of the hysteresis. The result has shown that the hysteresis characteristics become more pronounced as blade thickness becomes larger. The occurrence of these characteristics depends on the varying behavior of wakes between an accelerating flow and a develerating flow.

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Hysteresis Effects in Pool Boiling of Water (이력현상이 물의 풀비등에 미치는 영향)

  • Gang, Myeong-Gi
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.8
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    • pp.1037-1045
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    • 2001
  • The effect of hysteresis in saturated pool boiling of water from stainless-steel surfaces has been investigated experimentally. Several sets of test sections of different surface conditions, geometries, orientations, diameters, lengths, and water types were tested at atmospheric pressure. The experimental results show that hysteresis effects in pool boiling heat transfer are not significant, but some appreciable trends are observed in accordance with parameters change. At higher heat flux regions, the curve for heat flux decrease is shifted to the left side of the curve for heat flux increase. To clarify hysteresis in pool boiling and to give some improvement on published correlations, four empirical correlations are obtained in terms of tube diameter, surface roughness, and tube wall superheat.