• 제목/요약/키워드: High leakage current

검색결과 854건 처리시간 0.028초

급전선로에 설치되어 있는 피뢰기의 누설전류 측정과 관리방안 (Leakage Current Measurement and Management of Arresters Installed in Feeder Lines)

  • 한주섭;서황동;길경석;한문섭;장동욱
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 춘계학술대회 논문집
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    • pp.819-824
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    • 2005
  • This paper describes the measurement result of leakage current flowing arresters connected in feeder lines to propose an optimal management method. Twenty seven arresters set in seven areas were analyzed on a regular basis for 4 months. The results showed that the RMS and the peak value of the total leakage currents for soundness arresters were a range of $200uA{\sim}00uA$. respectively. During the period of measurement, the magnitude of the leakage current didn't show conspicious changes and there were impossible places to analyze arrester's status due to including high THD rate in a feeder line, From the study, leakage current measurement has to be performed at a condition without running an electric train in the line, and the allowable RMS value of soundness arrester is bellow 600uA.

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Modeling negative and positive temperature dependence of the gate leakage current in GaN high-electron mobility transistors

  • Mao, Ling-Feng
    • ETRI Journal
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    • 제44권3호
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    • pp.504-511
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    • 2022
  • Monte Carlo simulations show that, as temperature increases, the average kinetic energy of channel electrons in a GaN transistor first decreases and then increases. According to the calculations, the relative energy change reaches 40%. This change leads to a reduced barrier height due to quantum coupling among the three-dimensional motions of channel electrons. Thus, an analysis and physical model of the gate leakage current that includes drift velocity is proposed. Numerical calculations show that the negative and positive temperature dependence of gate leakage currents decreases across the barrier as the field increases. They also demonstrate that source-drain voltage can have an effect of 1 to 2 orders of magnitude on the gate leakage current. The proposed model agrees well with the experimental results.

Fabrication of Sputtered Gated Silicon Field Emitter Arrays with Low Gate Leakage Currents by Using Si Dry Etch

  • Cho, Eou Sik;Kwon, Sang Jik
    • Transactions on Electrical and Electronic Materials
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    • 제14권1호
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    • pp.28-31
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    • 2013
  • A volcano shaped gated Si-FEA (silicon field emitter array) was simply fabricated using sputtering as a gate electrode deposition and lift-off for the removal of the oxide mask, respectively. Due to the limited step coverage of well-controlled sputtering and the high aspect ratio in Si dry etch caused by high RF power, it was possible to obtain Si FEAs with a stable volcano shaped gate structure and to realize the restriction of gate leakage current in field emission characteristics. For 100 tip arrays and 625 tip arrays, gate leakage currents were restricted to less than 1% of the anode current in spite of the volcano-shaped gate structure. It was also possible to keep the emitters stable without any failure between the Si cathode and gate electrode in field emission for a long time.

Salt-fog 분무에 따른 실리콘 고무 애자의 표면열화 (Surface Degradation of Silicone Rubber Insulator by Salt-fog Test)

  • 장동욱;박영국;강성화;이용희;임기조
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.509-512
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    • 1999
  • The main problem in porcelain as a high voltage insulator is that the water film is felled on the insulator surface due to rain, flog, and dew. In the presence of contamination. leakage current increases which may lead to flashover that could be followed by an outage of the power system. These days, high voltage polymer outdoer insulators have been studied and widely used, because they have excellent electrical and mechanical properties, superior performance of flashover for contamination. light weight, easy installation or handling. no maintenance during service, competitive price, and so on. First of a1l the excellent performance of the silicone rubber in polluted and wet conditions is attributed to the ability of the material to maintain the hydrophobicity of the surface in the presence of severe contaminants and wet conditions. This is due to a low surface energy of the silicone rubber. But the leakage current and some surface discharge occurs on the surface of insulator when the insulator is used for a long time. So the leakage current and the surface discharge current are important lo estimate the condition of the silicone rubber surface. In this paper, the average leakage current the surface discharge current the surface rubber surface with the salt fog condition for the first stage.

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Excimer laser로 재결정화한 LDD구조의 poly-Si TFT 제작 (Fabrication of the LDD Structure poly-Si TFT with Excimer Laser Recrystallization Process)

  • 정준호;박용해
    • 전자공학회논문지A
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    • 제32A권2호
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    • pp.324-331
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    • 1995
  • The leakage current characteristics of the low temperature processed LDD structure poly-Si TFT is analyzed. The excimer laser technology was applied to the recrystallization process of poly-Si film and the maximum processing temperature was retained under 600.deg.C. From the fabricated LDD space 0.3.mu.m to 3$\mu$m, the best on/off current ration could be obtained with the 1.3$\mu$m LDD space. And the threshold voltage did not increase more than 4V over 0.8$\mu$m LDD space. The characteristics of leakage current was compared to non-LDD structure TFT to analyze the mechanism of leakage current. Consequently, it could be concluded that the leakage current is strongly affected by the trap states as well as high electric field between gate and drain.

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온도변화에 따른 GaAs MESFET′s 노이즈 특성 연구 (A study on the GaAs MESFET′s noise characteristics with temperature dependency)

  • 김시한;이명수;박지홍;안형근;한득영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집
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    • pp.322-325
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    • 2002
  • In this study, noise figures of 0.3 $\mu\textrm{m}$-GaAs MESFETs are predicted experimentally with different temperatures. Both the noise figure and the gate leakage current are obtained with wide range of temperatures(27$^{\circ}C$∼300$^{\circ}C$). From the results, gate leakage current increases with temperatures. It is expected that gate leakage current contributes directly to the increase of shot noise current. It is therefore highly recommended to apply an accurate noise analysis to the design of the devices and modules at high temperatures. Fini,Uy the relation between the gate currents resulting in the increase of noise and the noise figures of submicron GaAs MESFETs are traced with different temperatures

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고 효율, 저 잡음 특성을 가지는 양방향 태양광 인버터 (Bi-directional Photovoltaic Inverter with High Efficiency and Low Noise)

  • 이성호;권정민;권봉환
    • 전력전자학회논문지
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    • 제17권6호
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    • pp.539-545
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    • 2012
  • Due to merits cost and efficiency, the transformer-less type photovoltaic (PV) inverters have been popularized in the solar market. However, the leakage current flowing through a parasitic capacitor between PV array and ground can cause adverse effect in the transformer-less PV system. In this paper, a bi-directional PV inverter with high efficiency and low noise is proposed for the PV system with an energy storage device. The proposed inverter is a transformer-less type and performs the bi-directional power control between dc sources and grid with high efficiency. In addition, the proposed inverter can suppress the leakage current and obtain low noise characteristic. Finally, 3-kW prototype was implemented to confirm validity of the proposed inverter.

새로운 능동형 커먼 모드 전압 감쇄기를 이용한 고주파 누설전류 억제 (The suppression of high frequency leakage current using a new active Common Mode Voltage Damper)

  • 구정회;빈재구;박성준;김철우
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2001년도 전력전자학술대회 논문집
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    • pp.151-154
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    • 2001
  • This paper propose a new active common-mode voltage damper circuit that is capable of suppressing a common-mode voltage produced in the PWM VSI. The new active common mode voltage damper is consisted of a half-bridge inverter and a common mode transformer with a blocking capacitor. Principle of the active common mode damper is as follow; by applying the compensation voltage which has the same amplitude and opposite polarity to the PWM inverter system. So, common mode voltage and high frequency leakage current can be reduced. Simulated and experimental results show that common-mode voltage damper makes contributions to reducing a high frequency leakage current and common-mode voltage.

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Oxide-Nitride-Oxide막을 게이트 절연막으로 사용하여 제조한 다결정실리콘 박막트랜지스티의 특성 (Properties of Poly-Si TFT's using Oxide-Nitride-Oxide Films as Gate Insulators)

  • 이인찬;마대영
    • 한국전기전자재료학회논문지
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    • 제16권12호
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    • pp.1065-1070
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    • 2003
  • HTO(High Temperature Oxide) films are mainly used as a gate insulator for polysilicon thin film transistors(Poly-Si TFT's). The HTO films, however, show the demerits of a high leakage current and a low electric breakdown voltage comparing with conventional thermal oxides even though they have a better surface in roughness than the thermal oxides. In this paper, we propose an ONO(Oxide-Nitride-Oxide) multilayer as the gate insulator for poly-Si TFT's. The leakage current and electric breakdown voltage of the ONO and HTO were measured. The drain current variation of poly-Si TFT's with a variety of gate insulators was observed. The thickness optimization in ONO films was carried out by studying I$\_$on/I$\_$off/ ratio of the poly-Si TFT's as a function of the thickness of ONO film adopted as gate insulator.

플라즈마 표면 처리가 $BaTa_2O_6$박막의 전기적 특성에 미치는 효과에 관한 연구 (Influences of Plasma Treatment on the Electrical Characteristics of rf-magnefrom sputtered $BaTa_2O_6$ Thin Films)

  • 김영식;이윤희;주병권;성만영;오명환
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권5호
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    • pp.319-325
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    • 1999
  • Direct current(d.c.)leakage current voltage characteristics of radio-frequencymagnetron sputtered BaTa\sub 2\O\sub 6\ film capacitors with aluminum(A1) top and indium tin oxide (ITO) bottom electrodes have been investigatedas a function of applied field and temperature. In order to study surfacetreatment effect on the electrical characteristics of as-deposited film weperformed exposure of oxygen plasma on $BaTa_2O_6$ surface. d. c.current-voltage (I-V), bipolar pulse charge-voltage (Q-V), d. c. current-time (I-t) andcapacitance-frequency (C-f) analysis were performed on films. All ofthe films exhibita low leakage current, a high breakdown field strength (3MV/cm-4.5MV/cm), and high dielectric constant (20-30). From the temperature dependence of leakage current,we can conclude that the dominant conduction mechanism is ascribed toSchottky emission at high electric field (>1MV/cm) and hopping conduction at lowelectric field (<1MV/cm). According to our results, the oxide plasma surfacetreatmenton as-deposited $BaTa_2O_6$ resulted in lowering interfacebarrier height and thus, leakage current when a negative voltage applied to the A1 electrode. This can be explained by reduction of surface contamination via etching surface and filling defects such as oxygen vacancies.

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