• 제목/요약/키워드: V-t Characteristic

검색결과 176건 처리시간 0.029초

765kV 점퍼V련에서 활선작업 유형별 개폐섬락 특성실험 및 분석 (Switching Flashover Characteristic Tests and Analysis for Jumper V String in 765kV T/L Live Line Works)

  • 김대식;김효진;이형권;한상옥;김주한;구경완
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2007년도 춘계학술대회 논문집 전기설비전문위원
    • /
    • pp.20-23
    • /
    • 2007
  • 활선작업시 개폐섬락전압은 철탑형태와 작업유형에 따라 개폐섬락전압이 달리 나타나게 된다. 즉, 활선작업자의 위치, 철탑 종류 및 애자장치 종류 등에 따라 개폐섬락전압은 다르게 나타나기 때문에, 적용하고자 하는 활선공법이 있다면, 이에 대한 개폐섬락전압의 특성을 파악해 둘 필요가 있다. 점퍼V련은 일반적으로 선로의 수평각이 중각도 지역에 설치된다. 즉, 수평각이 너무 커서 조립식 점퍼장치를 설치할 수 없는 철탑에 점퍼V련 장치를 설치한다. 765kV 송전선로에서 실제 점퍼V련 장치가 많이 설치되어 있지 않으나, 이 경우에도 유지보수 사항이 발생할 수 있기 때문에 안전한 활선작업을 위한 실규모급 개폐섬락특성에 대해 검토할 필요가 있다.

  • PDF

EO Characteristic of the In-plane Driven VA Cells on a Polymer Layer

  • Lee Sang-Keuk;Hwang Jeoung-Yeon;Seo Dae-Shik
    • Transactions on Electrical and Electronic Materials
    • /
    • 제4권4호
    • /
    • pp.7-9
    • /
    • 2003
  • Viewing angle characteristics of a nematic liquid crystal (NLC) using a in-plane driven (IPD) vertical alignment (VA) cell without a negative compensation film on a homeotropic alignment layer were studied. Good voltage-transmittance (V - T) curves were obtained using the rubbing aligned IPD- VA cell. However, instability and low transmittances of V - T characteristics in photo aligned IPD- VA cell was measured. The EO performance of a rubbingaligned IPD- VA cell without a negative compensation film was wider than that of photoaligned IPD- VA cell and conventional VA cell. Also, the fabrication processes using the rubbing aligned IPD- VA cell mode be carried out with only one-sided rubbing.

EEPROM 셀에서 폴리실리콘 플로팅 게이트의 도핑 농도가 프로그래밍 문턱전압에 미치는 영향 (Effects of Doping Concentration in Polysilicon Floating Gate on Programming Threshold Voltage of EEPROM Cell)

  • 장성근;김윤장
    • 한국전기전자재료학회논문지
    • /
    • 제20권2호
    • /
    • pp.113-117
    • /
    • 2007
  • We have investigated the effects of doping concentration in polysilicon floating gate on the endurance characteristics of the EEPROM cell haying the structure of spacer select transistor. Several samples were prepared with different implantation conditions of phosphorus for the floating gate. Results show the dependence of doping concentration in polysilicon floating gate on performance of EEPROM cell from the floating gate engineering point of view. All of the samples were endured up to half million programming/erasing cycle. However, the best $program-{\Delta}V_{T}$ characteristic was obtained in the cell doped at the dose of $1{\times}10^{15}/cm^{2}$.

용량성 압력센서의 집적화에 관한 연구 (Study on Integrated for Capacitive Pressure Sensor)

  • 이윤희
    • 전자공학회논문지T
    • /
    • 제35T권1호
    • /
    • pp.48-58
    • /
    • 1998
  • 본 논문은 센서에서 수반되는 기생용량과 온도 드리프트 및 누설전류의 영향을 경감하기 위한 C-V변환회로 및 C-V변환회로에 관한 실험결과를 제시하고, 또한 논문에서 제안한 센싱 주파수를 기준주파수로 나누어줌으로써 상기 영향들을 줄일 수 있는 새로운 인터페이스 회로를 제시한다 이 회로는 용량비의 출력신호를 디지털 방식으로 16진수로 계수 함으로써 신호의 전송이나 컴퓨터 처리가 쉬울 뿐 아니라 비트수의 증가에 따라 분해 능을 향상시킬 수 있는 이점도 있다. 시작한 인터페이스 회로의 C-V 및 C-F 변환회로에서 전원전압 4.0V, 피이드백 커패시턴스10pF, 압력 0∼10 KPa범위에서 감도는 각각 28 ㎷/㎪·V, -6.6 ㎐/㎩로서 양호하였고, 온도 드리프트 특성은 0.051 %F.S./℃ 및 0.078 %F.S./℃로서 크게 개선되었다.

  • PDF

절반금속 Fe_2TX 화합물의 전자구조 연구 (T = 3d 전이금속; X = Al, Si) (Electronic Structures of half-metallic phase of ternary Fe_2TX (T = 3d transition metal and X = Al, Si))

  • Park, Jin-Ho;Kwon, Se-Kyun;Byung ll Min
    • 한국자기학회:학술대회 개요집
    • /
    • 한국자기학회 2000년도 International Symposium on Magnetics The 2000 Fall Conference
    • /
    • pp.584-584
    • /
    • 2000
  • Electronic structures of ordered Fe$_3X (X = Al, Si), and their derivative ternary alloys of Fe_2TX (T = 3d transition metal) have been investigated by using the linearized muffin-tin orbital (LMTO) band method. The role of the coupling between substituted transition metal and its neighbors is investigated by calculating the magnetic moments and local density of states (LDOS). It is shown that it is essential to include the coupling beyond nearest neighbors in obtaining the magnetic moment of Fe alloy. The preferential sites of T impurities in Fe_3X are determined from the total energy calculations. The derivative ternary alloys of Fe_2TX have characteristic electronic structures of semi-metal for Fe_2VAI and (nearly) half-metal for Fe_2TAI (T = Cr, Mn) and Fe_2TSi (T = V, Cr, Mn)

  • PDF

대용량 이차전지 보호 시스템용 전류 감지 동작형 보호소자의 저융점 금속 가용체 설계 (Design of Low-Melting Metal Fuse Elements of Current Sensing Type Protection Device for Large Capacity Secondary Battery Protection System)

  • 김은민;강창룡
    • 한국전기전자재료학회논문지
    • /
    • 제31권6호
    • /
    • pp.427-432
    • /
    • 2018
  • High-capacity secondary batteries can cause explosion hazards owing to microcurrent variations or current surges that occur in short circuits. Consequently, complete safety cannot be achieved with general protection that is limited to a mere current fuse. Hence, in the case of secondary batteries, it is necessary for the protector to limit the inrush current in a short circuit, and to detect the current during microcurrent variations. To serve this purpose, a fuse can be employed for the secondary battery protection circuit with current detection. This study aims at designing a protection device that can stably operate in the hazardous circumstances associated with high-capacity secondary batteries. To achieve the said objective, a detecting fuse was designed from an alloy of low melting point elements for securing stability in abnormal current states. Experimental results show that the operating I-T and V-T characteristic constraints can be satisfied by employing the proposed current detecting self-contained low melting point fuse, and through the resistance of the heating resistor. These results thus verify that the proposed protection device can prevent the hazards of short circuit current surges and microcurrent variations of secondary batteries.

휴대용 이차전지 보호 시스템용 전류 감지 동작형 보호소자의 퓨즈 가용체 설계 (Design of Fuse Elements of Current Sensing Type Protection Device for Portable Secondary Battery Protection System)

  • 강창룡;김은민
    • 전기학회논문지
    • /
    • 제67권12호
    • /
    • pp.1619-1625
    • /
    • 2018
  • Portable electronic devices secondary batteries can cause fire and explosion due to micro-current change in addition to the situation of short-circuit inrush current, safety can not be secured with a general operation limited current fuse. Therefore, in secondary battery, it is necessary for the protector to satisfy both the limit current type operation in the open-short-circuit inrush current and the current detection operation characteristic in the micro current change situation and for this operation, a fuse for the current detection type secondary battery protection circuit can be applied. The purpose of this study is to design a protection device that operates stably in the hazardous situation of small capacity secondary battery for portable electronic devices through the design of low melting fuse elements alloy of sensing type fuse and secures stability in abnormal current state. As a result of the experiment, I-T and V-T operation characteristics are satisfied in a the design of the alloy of the current sensing type self-contained low melting point fuse and the resistance of the heating resistor. It is confirmed that it can prevent accidents of short circuit over-current and micro current change of secondary battery.

신호현시 정보 제공 시스템의 시간 지연특성 연구 (A Study on the Time Delay Characteristics of Traffic Signal Phase and Timing Information Providing System)

  • 배정규;서경덕;서우창;서대화
    • 자동차안전학회지
    • /
    • 제14권3호
    • /
    • pp.48-59
    • /
    • 2022
  • A V2X system can be a candidate as a means to increase the stability of autonomous vehicles. In particular, in order to implement a Level 4 or higher autonomous driving system, the application of the V2X system is essential. Wireless communication technologies applicable to the V2X system include WAVE and C-V2X. Currently, the V2X service most used by autonomous driving systems is a service that provides signal phase and timing information and since real-time characteristic is a very important, verification of this service must be done. In this paper, we measured the time delay characteristics for providing signal phase and timing information using WAVE and LTE communication, and proposed a TOD-based signal phase and timing information generation method without using V2X communication system. To analyze the time delay characteristics, RTT (Round Trip Time) was measured as a result of the measurement. Average RTT using WAVE communication was 5.84ms and was 104.15ms with LTE communication. As a result of measuring the error between the signal phase and timing information generated based on TOD and the actual traffic light state, it was measured to be -0.284~3.784sec.

Phanerochaete chrysosporium PSBL-1을 이용한 축산폐수와 하수의 연계처리 (Combined Treatment of Livestock Wastewater with Sewage Using Phanerochaete chrysosporium PSBL-1)

  • 이순영;조홍식;원찬희
    • 대한환경공학회지
    • /
    • 제28권3호
    • /
    • pp.286-291
    • /
    • 2006
  • 본 연구에서는 축산폐수와 하수의 연계처리 가능성을 연구하였다 축산폐수와 하수를 2:1로 혼합하고 응집제인 BF02와 응집보조제인 양이온 polymer인 C-210EL를 각각 2 mL, 100 mL씩 주입시 SS 97.6%, T-P 95%로 최적 제거효율을 보였다. Phanerochaete chrysosporium PSBL-1의 처리 특성을 살펴보기 위해서 전처리수를 축산폐수 원수에 대해 10배 희석되도록 하수와 혼합($\fallingdotseq$전처리수:하수=3:17)하였다. 이렇게 혼합된 폐수의 NBDCOD, $NH_3-N$, T-N의 제거율은 pH가 증가할수록 증가하였다. 즉, T-N 농도는 pH 6.7(5일 경과시), pH 8.0(3일 경과시), pH 10.0(1일 경과시)에서 각각 35 mg/L, 51 mg/L, 33 mg/L으로 축산폐수공공처리시설의 방류수허용기준 60 mg/L을 만족하였다. 또한 모든 pH(1일 경과시)에서 $COD_{Mn}$의 방류수허용기준 40 mg/L을 만족했다. V.A.(veratryl alcohol) 첨가시 V.A.를 첨가하지 않은 조건보다 유출수의 유기물 및 질소농도가 높게 측정되었다. $COD_{Mn}$은 C/N비(3:1)를 조절하지 않은 경우 1일 이후, T-N은 C/N비를 $4{\sim}6$으로 조절한 경우 2일 후에 축산폐수공공처리시설 방류수수질기준을 만족하였다.

NASICON 고체 전해질의 이온 전도도 계산 (II) Na1-Na2 전도 경로에 미치는 mid-Na의 영향 (Computation of Ionic Conductivity at NASICON Solid Electrolytes (II) Effects of mid-Na Sites on Na1-Na2 Conduction Paths)

  • 최진삼;서양곤;강은태
    • 한국세라믹학회지
    • /
    • 제32권11호
    • /
    • pp.1292-1300
    • /
    • 1995
  • The ionic conductivity of NASICON solid electrolytes was simulated by using Monte Carlo Method (MCM). There were included two conduction paths: (1) Na1-Na2 and (2) Na1-Na2 including Na2-Na2. We assumed that mid-Na ions provde an additional driving force for Na mobile ions due to the interionic repulsion between Na1 and Na2 ions. The inflection point of vacancy availability factor, V has been shown at nearby x=2, the maximum mid-Na ions. The inflection point of vacancy availability factor, V has been shown at nearby x=2, the maximum mid-Na sites are occupied. The effective jump frequency factor, V has been shown at nearby x=2, the maximum mid-Na sites are occupied. The effective jump frequency factor, W increased rapidly with the composition at low temperature, but decreased at high temperature region. On Na1-Na2 conduction path, the minimum of charge correlation factor, fc and the maximum of $\sigma$T were appeared at x=2.0. this indicated that mid-Na ions affect on the high ionic conductivity behavior. At the whole range of NASICON composition, 1n $\sigma$T vs. 1/T* plots have been shown Arrhenius behavior but 1n (VWFc) vs. 1/T* have been shown the Arrhenius type tendency at x=2, which mid-Na is being the maximum. The results of MCM agreed with the experimental one when the chosen saddle point value was 6$\varepsilon$ : 3$\varepsilon$. Here the calculated characteristic parameter of materials, K and the phase transition temperature were -4.001$\times$103 and 178$^{\circ}C$ (1/T*=1.92, 1000/T=2.22), respectively.

  • PDF