• 제목/요약/키워드: 산화아연 바리스터

검색결과 21건 처리시간 0.022초

프라세오디뮴계 산화아연 바리스터의 전기적 특성에 코발트 산화물 첨가의 영향 (Effect of Cobalt Oxide Addition on Electrical Properties of Praseodymium-based Zinc Oxide Varistors)

  • 남춘우;박종아;유대훈;서형권
    • 한국전기전자재료학회논문지
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    • 제18권10호
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    • pp.896-901
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    • 2005
  • The microstructure and electrical properties of praseodymium-based zinc oxide varistors were investigated at various cobalt oxide contents in the range of $0.5{\~}5.0 mol\%$. The ceramic density increased in the range of $5.25{\~}5.55 g/cm^3$ with increasing cobalt oxide content. The varistor doped with cobalt oxide of $1.0 mol\%$ exhibited the highest nonlinearity, with 66.6 in nonlinear exponent and 1.2 $\mu$A in leakage current. The donor concentration, density of interface states, and tamer height were in the range of $(1.06{\~}1.69){\times}10^{18}/cm^3$, $(3.11 {\~}3.56){\times}10^{12}/cm^2$, and 0.80${\~}$1.07 eV, respectively.

$Y_2O_3$가 첨가된 비스무스계 산화아연 바리스터의 미세구조 및 전도특성 (Microstructure and Conduction Characteristics of Bismuth-Based Zinc Oxide Varistors with $Y_2O_3$Additive)

  • 박춘현;남춘우
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 추계학술대회 논문집
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    • pp.281-285
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    • 1998
  • The microstructure and conduction characteristics of ZnO varistor fabricated in the range of 0.0 ~ 4.0mol% $Y_20_3$ were investigated. With increasing$Y_20_3$ content, distribution of spinel phase decreased, whereas Y-rich phase segregated to the nodal point increased, as a result, the average grain size decreased in the range of $20.0 ~ 4.8{\mu}m$. $Y_20_3$ content showing relatively good conduction characteristics was l.Omol%, then nonlinear exponent and leakage current was 55.3, 0.66mA.respectively.

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ZnO세라믹스의 소결온도가 전기적 특성에 미치는 영향 (The effect of sintering temperature on the electrical properties of ZnO ceramics)

  • 김용혁;이덕출
    • E2M - 전기 전자와 첨단 소재
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    • 제8권1호
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    • pp.40-47
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    • 1995
  • Electrical properties of ZnO ceramics based on Bi oxide was investigated in relation to sintering temperature. In the temperature range >$1150^{\circ}C$ to >$1350^{\circ}C$ the grain size increased from 9.mu.m to 20.mu.m when the sintering temperature was raised. The leakage current in the low voltage range increased as the potential barrier decreases, which is caused by increasing the grain size at high temperature. The dielectric characteristics of the ZnO ceramics was also affected by sintering temperature. Large dielectric constant was attributed, to the grainboundary layer of polycrystalline ZnO ceramics and decreasing grainboundary width. The variation of breakdown voltage with sintering temperature was attributed to the change of the donor concentration in the ZnO grain and grain size. The results showed that breakdown voltage increased decreasing grain size and donor concentration. Nonohmic coefficient was associated with the lower breakdown voltage per grainboundary layer due to the grain growth and higher donor concentration.

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가스튜-브와 산화아연 바리스터의 PSpice 모델 (A PSpice Model of Gas Tube and ZnO Varistor)

  • 송재용
    • Journal of Advanced Marine Engineering and Technology
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    • 제23권2호
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    • pp.150-158
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    • 1999
  • The process of designing protective circuits against damage by transient overvoltages requires much work and expensive equipment. However computer simulation using PSpice can overcome these problems. In this paper a gas tube and a ZnO varistor Pspice-model considering the steepness of the wave-front were presented. The effects of various waveforms on the transient behaviors and firing volt-ages of a gas tube were modeled by controlled voltage source E controlled current source G and TABLE function of PSpice. And the nonlinear characteristics of a ZnO varistor were modeled by controlled voltage source E and H. To estimate the characteristics of the models proposed various waveforms specified in IEC Std. 1000310-4-5 were used in the simulation and the actual tests. The simulation results were compared with test results and showed good agreement.

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$ZnO-Pr_6/O_{11}-CoO-Er_2O_3$계 세라믹스의 바리스터 특성 (Varistor Characteristics of $ZnO-Pr_6/O_{11}-CoO-Er_2O_3$-Based Ceramics)

  • 윤한수;박춘현;남춘우
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.308-311
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    • 1999
  • The varistor characteristics of $ZnO-Pr_6O_11-CoO-Er_2O_3$-based ceramics were investigated. $ZnO-Pr_6O_11-CoO-Er_2O_3$-based ceramics were sintered at $1300^{\circ}C$ and $1350^{\circ}C$in the addition range 0.0~2.0mol% $Er_2O_3$, respectively. $ZnO-Pr_6O_11-CoO-Er_2O_3$-based ceramics, which are added with 0.5mol% $Er_2O_3$ at $1300^{\circ}C$ and l.Omol% $Er_2O_3$ at $1350^{\circ}C$ sintering temperature, exhibited the bestexcellent varistor characteristics, namely, the nonlinear exponent was better 52.78 at $1300^{\circ}C$ thanat 13$1350^{\circ}C$ and the leakage current was better 6.57$\mu\textrm$A at $1350^{\circ}C$ than at $1300^{\circ}C$. Consequently, it is estimated that $ZnO-Pr_6O_11-CoO-Er_2O_3$-based ceramics, which $Er_2O_3$ is added in the range 0.5~l.Omol% will begin to be used as a predominant basic composition of $PR_6O_11$-based ZnO varistors.

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산화아연 피뢰기소자에 흐르는 저항분 누설전류의 검출기법 (A Detection Method of Resistive Leakage Current Flowing through ZnO Arrester Blocks)

  • 이복희;강성만
    • 조명전기설비학회논문지
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    • 제15권3호
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    • pp.67-73
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    • 2001
  • 본 논문에서는 ZnO 피뢰기 소자에 대한 내구성 평가와 열화실험을 위한 저항분 누설전류 검출장치의 개발과 열화진단기법에 대하여 기술하였다. 저항분 누설전류는 ZnO 피뢰기 소자가 정상상태인지 불안정상태인지에 대한 판단의 지표로서 사용할 수 있다. 본 논문에서는 보상회로로 구성된 저항분 누설전류 측정시스템을 설계하여 구성하고, 실증실험으로서 ZnO 소자에 대한 저항분 누설전류의 측정과 고속프리에 변환기법(Fast Fourier transform)을 통해 저항분 누설전류의 주파수특성을 조사·분석하였다. 분석결과 제안한 저항분 누설전류의 측정 시스템은 실험실에서 산화아연 바리스터의 전기적·물성적 특성을 연구하고, 전력계통에 있어서 ZnO 피뢰기의 열화의 진단과 예측기술을 개발하는데 유용하게 활용할 수 있다.

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코발트 산화물 첨가가 산화아연 바리스터의 전기적, 유전적 안정성에 미치는 영향 (The Effect of Cobalt Oxide Addition on Electrical and Dielectic Stability of Zinc Oxide Varistors)

  • 남춘우;유대훈
    • 한국재료학회지
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    • 제15권11호
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    • pp.722-729
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    • 2005
  • The electrical and dielectric stability of zinc oxide-based varistors were investigated with the cobalt oxide contents in the range of $0.5\~5.0 mo\l%$. As cobalt oxide contents increased, the ceramic density increased in the range of $5.25\~5.55g/cm^3$ and the varistor voltage decreased in the range of $235.3\~86.0V$. The varistor with on addition of cobalt oxide $1.0 mol\%$ exhibited good nonlinearity. in which the nonlinear exponent is 66.6 and the leakage current is $1.2{\mu}A$. Furthermore, the varistors exhibited the highest electrical and dielectric stability, with $\%{\Delta}V_{1mA}=-1.9\%,\;\%{\Delta}{\alpha}=-10.5\%,\;\%{\Delta}I_L=+275.0\%,\;and\;\%{\Delta}tna{\delta}=+55.6\%$, under DC accelerated aging $0.95V_{1mA}/150^{\circ}C/24h$.

$ZnO-Pr_6O_{11}-CoO-Dy_2O_3$계 바리스터의 I-V 특성에 $Pr_6O_{11}/CoO$ 조성비 영향 (Influence of $Pr_6O_{11}/CoO$ Composition Ratio on I-V Characteristics of $ZnO-Pr_6O_{11}-CoO-Dy_2O_3$ Based varistors)

  • 남춘우;류정선;윤한수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 영호남학술대회 논문집
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    • pp.179-184
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    • 2000
  • The I-V characteristics of $ZnO-Pr_6O_{11}-CoO-Dy_2O_3$ based varistors were investigated in the $Pr_6O_{11}/CoO$ composition ratio range of 0.5/0.5 to 1.0/1.0 and sintering temperature range of 1300 to $1350^{\circ}C$ as the basic study to develop the advanced $Pr_6O_{11}$-based ZnO varistors. All varistors except for $Pr_6O_{11}$/CoO = 0.5/1.0 exhibited the best I-V characteristics at $1350^{\circ}C$. However, the varistors with $Pr_6O_{11}$/CoO= 0.5/1.0 exhibited the best I-V characteristics at $1350^{\circ}C$. The varistors with $Pr_6O_{11}$/CoO= 0.5/1.0 of all varistors exhibited the best I-V characteristics, which the nonlinear exponent is 36.9 and the leakage current is 7.6 ${\mu}A$ Therefore, it was estimated that ZnO-$Pr_6O_{11}-CoO-Dy_2O_3$ ceramics with $Pr_6O_{11}$/CoO= 0.5/1.0 will be usefully used as varistor materials in the future.

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뇌충격전류에 의한 산화아연형 바리스터의 전기적 특성변화 (Changes of Electrical Characteristic of ZnO Varistors by a Lightning Impulse Current)

  • 이종혁;손원진;김명진;길경석
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2000년도 추계종합학술대회
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    • pp.581-584
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    • 2000
  • This paper describes the effect of lightning impulse current on ZnO varistors(390 V, 6.5 kA) used in low-voltage AC mains as a protective device against transient overvoltages. A lightning impulse current standardized in IEC 61000-4-5 is applied to the varistors, and the energy applied to the varistor at each time is about 12 J. In the experiment, various Parameters such as leakage current, reference voltage are measured with the number of applied impulse current. Also, micro-structure changes of the varistors after applying the lightning impulse current of 200 times are compared. The electrical characteristics of the varistors are degraded by overtime impulse current, showing increase in leakage current and decrease in reference voltage.

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뇌서지 전류에 대한 산화아연바리스터의 Pspice 시뮬레이션 모델 (Pspice Simulation Model of a ZnO Varistor for Lightning Surge Current)

  • 이복희;공영훈;이경옥;강성만
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 E
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    • pp.1675-1677
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    • 1998
  • It is currently increasing to use surge protection devices in the protection of various electronic circuits from the transient overvoltages such as lightning strikes and switching surges. For this reason, the simulation methods, which can easily predict the protection performance of the devices, are strongly required in order to design the adequate surge protection circuits in lightning surge cut-off performance and economic aspects. This paper deals with ZnO varistor modeling method for designing a surge protection circuit and suggests the Pspice simulation model which takes the characteristic of varying clamping voltage into consideration during the time-to-crest, in range of $8{\sim}30{\mu}s$, of surge current applied to a ZnO varistor. The ZnO varistor Pspice simulation data introduced in this paper has produced almost same values as the measured results experimentally.

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