• 한국시뮬레이션학회논문지
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• 제30권2호
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• pp.33-40
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• 2021

고고도 전자기 펄스(HEMP)의 상황은 고고도 핵폭발로 인해 발생한다. HEMP상황은 위협 레벨 조사(TLI)를 통해 HEMP 상황을 시뮬레이션 할 수 있다. 본 논문에서는 전술기동무선통신체계의 안테나 종류에 따른 유도 전압을 위협 레벨 조사로 측정 및 분석 하였다. HEMP의 영향을 받으면 전자 장비가 마비되거나 손상 될 수 있다. HEMP 방호 필터는 전원선 및 신호선용으로 상용화되어 있다. 그러나 안테나용 HEMP 필터는 상용화가 부족한 편이며 존재하더라도 낙뢰보호용으로 제작되어 있다. 안테나의 주파수와 종류에 따라 적절한 HEMP 방호 필터를 만들기 위해 유도 전압을 측정하고 외삽법을 통해 최대 유도 전압을 분석하였다. 측정 결과 HF, VHF, UHF 대역과 같이 주파수가 증가할수록 측정된 유도전압은 감소하는 것으로 나타났다.

• Journal of Power Electronics
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• 제17권1호
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• pp.212-221
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• 2017

Permanent-Magnet Synchronous Generators (PMSGs) are used widely in Wind Power Generation Systems (WPGSs), and the Vienna rectifier was recently proposed to be used as the generator-side converter to rectify the AC output voltage in PMSG-based WPGS. Compared to conventional six-switch two-level PWM (2L-PWM) converters, the Vienna rectifier has several advantages, such as higher efficiency, improved total harmonic distortion, etc. The motivation behind this paper is to verify the performance of direct-driven PMSG wind turbine system based-Vienna rectifier by using a simulated direct-driven PMSG WPGS. In addition, for the purpose of reducing the reactive power loss of PMSGs, this paper proposes an induced voltage sensing scheme which can make the stator current maintain accurate synchronization with the induced voltage. Meanwhile, considering the Neutral-Point Voltage (NPV) variation in the DC-side of the Vienna rectifier, a NPV balancing control strategy is added to the control system. In addition, both the effectiveness of the proposed method and the performance of the direct-driven PMSG based-Vienna rectifier are verified by simulation and experimental results.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.285-288
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• 2007

This article presents the change characteristics of induced noise whether the sheath layer of the cable is grounded or not. As what affects the induced noise, there are power influence or longitudinal transverse voltages and its weighted filtered voltage. The sheath ground is basicaly predicted to have the effects of alleviation on the power influence. But practically the effects may not happen in the case of common cable's sheath layer. Rather there are cases that the ground of sheath affects so that the noise level could increase. So we need to scrutinize the effects of the sheath gorund in the measures for the protection against electromagnetic induction by powerline or traction line system. And the evaluation of using the designated shielding purpose cable is needed.

• Transactions on Electrical and Electronic Materials
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• 제4권6호
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• pp.32-37
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• 2003

In this paper, the trap characteristics of thin silicon oxides is investigated in the ULSI implementation with nano structure transistors. The stress and transient currents associated with the on and off time of applied voltage were used to measure the distribution of high voltage stress induced traps in thin silicon oxide films. The stress and transient currents were due to the charging and discharging of traps generated by high stress voltage in the silicon oxides. The transient current was caused by the tunnel charging and discharging of the stress generated traps nearby two interfaces. The stress induced leakage current will affect data retention in electrically erasable programmable read only memories. The oxide current for the thickness dependence of stress current, transient current, and stress induced leakage currents has been measured in oxides with thicknesses between 113.4nm and 814nm, which have the gate area 10$\^$-3/ $\textrm{cm}^2$. The stress induced leakage currents will affect data retention, and the stress current and transient current is used to estimate to fundamental limitations on oxide thicknesses.

• Structural Engineering and Mechanics
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• 제48권4호
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• pp.435-453
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• 2013

A new computational approach for the rain load on the transmission tower is presented to obtain the responses of system subjected to the wind and rain combined excitations. First of all, according to the similarity theory, the aeroelastic modeling of high-voltage transmission tower is introduced and two kinds of typical aeroelastic models of transmission towers are manufactured for the wind tunnel tests, which are the antelope horn tower and pole tower. And then, a formula for the pressure time history of rain loads on the tower structure is put forward. The dynamic response analyses and experiments for the two kinds of models are carried out under the wind-induced and wind-rain-induced actions with the uniform and turbulent flow. It has been shown that the results of wind-rain-induced responses are bigger than those of only wind-induced responses and the rain load influence on the transmission tower can't be neglected during the strong rainstorm. The results calculated by the proposed method have a good agreement with those by the wind tunnel test. In addition, the wind-rain-induced responses along and across the wind direction are in the same order of response magnitude of towers.

• 대한방사선기술학회지:방사선기술과학
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• 제11권1호
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• pp.33-41
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• 1988

This study was measured the radiation-induced current - X-ray dose, dose rate, X-ray quality, time, temperature, electric field characteristics and the dependence of gap length in insulating oil under of D.C. Voltage before, during and after X-ray irradiation. The obtained results can be summarized as following. 1. The radiation - induced current is more the dependence of X-ray quality (tube voltage) than quantity (tube current), the dependence of quantity is appeared at the high than low X-.ay tube voltage. 2. The dependence of dose rate is appeared at the more dose rate, and ${\triangle}\;=\;0.64{\sim}0.74$. 3. The higher temperature of insulating oil and X-ray tube voltage (X-ray quality) is increased, at the low electric field, the more radiation-induced current. 4. $G_{eq}-G_{o}(={\triangle}G)$ is increased at the low than high temperature, high than low X-ray quality. 5. The dependence of temperature is appeared before than during X-ray irradiation. 6. The RIC saturation region is appeared at the high than low insulating oil temperature during (1000 V/cm above) than before (4000 V/cm above) X-ray irradiation.

• 조명전기설비학회논문지
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• 제16권6호
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• pp.51-59
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• 2002

논문은 가전기구의 사용으로 발생하는 유도전압 및 자장의 측정과 분석에 대한 것으로 본 실험에 사용한 유도전압과 자장 측정회로는 유도코일, 선행증폭기, 그리고 능동적분기로 구성하였다. TV와 퍼스널 컴퓨터용 모니터는 스위칭소자로 동작하는 전원장치를 사용하므로 고조파 성분을 많이 포함하는 강한 자장과 유도전압을 발생시켰다. 14"TV 주변에서 큰 자장과 높은 유도전압이 나타났고, 그 값은 측정거리 0.4 ［m］에서 각각 2.1 ［$\mu$Tp-p］와 140［mVp-p］이었다. 그러나 동일한 측정거리에서 단위 자장의 세기에 대한 유도전압은 17"모니터에서 약560 ［mV/$\mu$T］로 가장 크게 나타났다.장 크게 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.21-24
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• 2002

In this paper, induced voltages of the secondary conductors of a linear induction motor(LIM) with cage-type secondary are measured and analyzed when the LIM is fed by PWM inverter. The attenuation constant of the induced voltage of the secondary conductors near entry and exit zones of the the travelling magnetic field are determined from the experiment results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.803-806
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• 1997

The AC induced voltage on underground pipelines not only do harm to workers and instruments, but also cause big trouble in some case. This paper gives the mechanisms, examples, and countermeasure for the AC induced voltages which are caused by the resistive coupling between the grounding system of the 22.9kV distribution power system and the underground pipeline.

• 한국안전학회지
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• 제30권4호
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• pp.26-31
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• 2015

The purpose of this paper is to measure the induced voltage of the downscaled and simulated overhead ground wire of a 22.9kV-Y distribution line. This study performed a test of the downscaled and simulated distribution line according to whether it is grounded or not and the value of the ground resistance. In order to verify the reliability of the data measured by the test, the data was analyzed using the Minitab 17 program. It was found that the induced voltage of the downscaled and simulated distribution line is influenced by the value of the ground resistance. It was also found that the ground resistance obtained at a certain point is closely related to whether electric poles are grounded or not. The analysis results of the measured test data with a statistical method showed that the Anderson Darling (AD) was analyzed to be the smallest as 0.188 when the ground resistance of the electric poles had been maintained at $10{\Omega}$. In addition, the P value analyzed to be 0.894 which is in the proximity of the theoretical value of 1 and verified the reliability of the test data. It could be seen that the data measured by the downscaled simulation test forms a linear graph. It is thought that if a distribution line is installed in the same manner as the downscaled, simulated distribution line, the mean induced voltage will be reduced and reliability will be increased.