• ETRI Journal
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• 제35권5호
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• pp.797-807
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• 2013

In this paper, an input receiver with a hysteresis characteristic that can work at voltage levels between 0.9 V and 5 V is proposed. The input receiver can be used as a wide voltage range Schmitt trigger also. At the same time, reliable circuit operation is ensured. According to the research findings, this is the first time a wide voltage range Schmitt trigger is being reported. The proposed circuit is compared with previously reported input receivers, and it is shown that the circuit has better noise immunity. The proposed input receiver ends the need for a separate Schmitt trigger and input buffer. The frequency of operation is also higher than that of the previously reported receiver. The circuit is simulated using HSPICE at 0.35-${\mu}m$ standard thin oxide technology. Monte Carlo analysis is conducted at different process conditions, showing that the proposed circuit works well for different process conditions at different voltage levels of operation. A noise impulse of ($V_{CC}/2$) magnitude is added to the input voltage to show that the receiver receives the correct logic level even in the presence of noise. Here, $V_{CC}$ is the fixed voltage supply of 3.3 V.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.701-702
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• 2012

• International Journal of Precision Engineering and Manufacturing
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• 제4권3호
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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.

• 전력전자학회논문지
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• 제19권2호
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• pp.139-148
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• 2014

State-of-charge (SOC) is one of the significant indicators to estimate the driving range of the electric vehicle and to control the alternator of the conventional engine vehicles as well. Therefore its precise estimation is crucial not only for utilizing the energy effectively but also preventing critical situations happening to the power train and lengthening the lifetime of the battery. However, lead-acid battery is time-variant, highly nonlinear, and the hysteresis phenomenon causes large errors in estimation SOC of the battery especially under the frequent discharge/charge. This paper proposes a novel estimation technique for the SOC of the Lead-Acid battery by using a well-known Extended Kalman Filter (EKF) and an electrical equivalent circuit model of the Lead-Acid battery considering diffusion and hysteresis characteristics. The diffusion is considered by the reconstruction of the open circuit voltage decay depending on the rest time and the hysteresis effect is modeled by calculating the normalized integration of the charge throughput during the partial cycle. The validity of the proposed algorithm is verified through the experiments.

• 전기학회논문지
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• 제56권1호
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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.

• 조명전기설비학회논문지
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• 제28권4호
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• pp.21-28
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• 2014

Daily use characteristics of apparent power supplied to distribution transformer can be separated into two different time zone of waking hours and sleeping hours. In sleeping hours, using amount of power is decreasing. The actual curve of power seemed to be quite similar to this kind of separation. Inserting a condenser into a circuit in each different time zone led to maximize power factor of the transformer. The compensating condenser's on/off time is controlled by hysteresis circuit utilizing op amp and power factor of the transformer was improved from 0.945 to 0.999. As a result, the average of current reduction was 2.53A per hour of transformer.

• Journal of Power Electronics
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• 제16권2호
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• pp.643-653
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• 2016

The conventional methods used to evaluate battery state-of-charge (SOC) cannot accommodate the chemistry nonlinearities, measurement inaccuracies and parameter perturbations involved in estimation systems. In this paper, an impedance-based equivalent circuit model has been constructed with respect to a LiFePO₄ battery by approximating the electrochemical impedance spectrum (EIS) with RC circuits. The efficiencies of approximating the EIS with RC networks in different series-parallel forms are first discussed. Additionally, the typical hysteresis characteristic is modeled through an empirical approach. Subsequently, a methodology incorporating an H-infinity observer designated for open-circuit voltage (OCV) observation and a hysteresis model developed for OCV-SOC mapping is proposed. Thereafter, evaluation experiments under FUDS and UDDS test cycles are undertaken with varying temperatures and different current-sense bias. Experimental comparisons, in comparison with the EKF based method, indicate that the proposed SOC estimator is more effective and robust. Moreover, test results on a group of Li-ion batteries, from different manufacturers and of different chemistries, show that the proposed method has high generalization capability for all the three types of Li-ion batteries.

• 전기전자학회논문지
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• 제17권3호
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• pp.324-331
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• 2013

본 논문에서는 멤리스터 에뮬레이터 회로를 PCB 보드 상에서 구현하여 이의 측정을 통해서 멤리스터의 고유한 pinched hysteresis 특성을 관찰하였다. PCB 보드 상에서 구현된 멤리스터 에뮬레이션 회로는 간단한 부품으로 구성되어 있고 복잡한 회로 블록을 사용하지 않았기 때문에 집적회로의 구현 시에도 매우 작은 면적으로 설계가 가능하다는 장점이 있다. 또한 본 논문에서는 프로그램 가능한 이득증폭기를 멤리스터 에뮬레이션 회로를 사용하여 설계해서 이 회로의 전압이득이 멤리스터의 저항의 프로그래밍을 통해서 조절이 가능하다는 것을 보였다. 이득증폭기에 사용되는 멤리스터 에뮬레이션 회로의 구현을 위해서 멤리스터 소자의 특성 중에 하나인 threshold switching 특성이 회로로 구현되어 VREF 보다 낮은 전압이 인가되었을 때는 멤리스터의 저항 값이 변하지 않도록 설계하였고 이의 동작을 시뮬레이션을 통해서 검증하였다. 본 논문에서 PCB 보드 상에서 구현되고 검증된 멤리스터 에뮬레이션 회로와 이 회로를 이용한 프로그램 가능한 이득증폭기는 멤리스터 소자의 실제 제작이 불가능한 경우에, 멤리스터의 동작과 기능, 특성 및 멤리스터 응용회로의 이해에 많은 도움이 될 것이다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 하계종합학술대회 논문집(2)
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• pp.447-450
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• 2004

The modeling circuit becomes more important in developing various magnetic devices regarding the fact that the competitive architecture and circuitry should be developed simultaneously. In this paper, we introduce a modeling circuit for hysteresis characteristic of a magnetic device, which is a major characteristic in the spin dependent magnetic material. This transistor-level model is conspicuous in that it can be usefully embodied in real circuits rather than conventional SPICE models are only for simulations.

• 전자공학회논문지SC
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• 제48권2호
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• pp.56-63
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• 2011

본 논문에서는 마이크로프로세서의 디지털 입력포트에 히스테리시스 특성을 부여하는 방법 및 설계 순서를 제시하고 이를 실험해 그 효과를 확인하였다. 프로세서의 잉여포트가 있을 때 제시한 방법을 이용하면 저항 2개의 추가만으로 히스테리시스 특성을 얻을 수 있으며, 더구나 기존의 TTL과 CMOS의 슈미트 트리거 게이트에 비해 큰 히스테리시스 폭을 얻을 수 있다.