• 제목/요약/키워드: Power Qualify

검색결과 82건 처리시간 0.027초

단상용 통합형 전력품질 개선장치의 개발에 관한 기초연구 (A Basic Study on the Development of the Single-Phase Unified Poorer Quality Conditioner)

  • 노대석;이현옥;오성철;최재석;차준민;김재언
    • 대한전기학회논문지:전력기술부문A
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    • 제52권2호
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    • pp.90-98
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    • 2003
  • Recently, the increasing application of electronic equipments and information devices has heightened the interest in power qualify. The term power quality is applied to a wide range of electromagnetic phenomena on the power system and is also concentrated by all areas such as utilities, their customers and suppliers of load equipments. In engineering terms, power Qualify is expressed by voltage qualify because the power supply system can only control the quality of the voltage. Therefore, the standards in power quality area are devoted to keep the supply voltage within allowable limits. This paper deals with single-phase unified power quality conditioner (UPQC), which ai s at the integration of series-active and shunt-active filter. The series filter il used to compensate for the voltage distortions and the shunt filter is used to provide reactive power and counteract the harmonic current injected by the load. Also, the voltage of the DC link capacitor is controlled to a desired value by the shunt active filter. The validity of the proposed UPQC is demonstrated using both the MATLAB/SIMULINK simulation and the experimental device with DSP (TMS320C32).

150kVA급 전기품질 보상기기 제어 알고리즘 설계 (The Design of control algorithm for 150kVA power quality compensator)

  • 전진흥;김지원;전영환;김호용
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 B
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    • pp.1070-1072
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    • 2001
  • In recent years, customers and power supplies are interested in power quality. Demands of customers are change from standard quality of distribution power system to various high quality of distribution power system. so, it is necessary to apply power quality compensator, in our project, we develop the power quality compensator of 150kVA which compensates power factor and voltage sag, interruption. it is very frequently occurred power qualify problems[1,2]. As a series and shunt compensator, power quality compensator consists of two inverters with common do link capacitor bank. It compensates the current quality in the shunt part and the voltage qualify in the series part. In this paper we present the design and control algorithm of power quality compensator. As a control algorithm is implemented by digital controller, we consider sample-and-hold of signals. In this simulation, we use EMTDC/PSCAD V3.0 software which can simulate instantaneous voltage and current.

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고능률 가공을 위한 절삭 동력 기반의 이송 속도 최적화 (Cutting Power Based Feedrate Optimization for High-Efficient Machining)

  • 조재완;김석일
    • 대한기계학회논문집A
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    • 제29권2호
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    • pp.333-340
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    • 2005
  • Feedrate is one of the factors that have the significant effects on the productivity, qualify and tool life in the cutting mechanism as well as cutting velocity, depth of cut and width of cut. In this study, in order to realize the high-efficient machining, a new feedrate optimization method is proposed based on the concept that the optimum feedrate can be derived from the allowable cutting power since the cutting power can be predicted from the cutting parameters as feedrate, depth of cut, width of cut, chip thickness, engagement angle, rake angle, specific cutting force and so on. Tool paths are extracted from the original NC program via the reverse post-processing process and converted into the infinitesimal tool paths via the interpolation process. And the novel NC program is reconstructed by optimizing the feedrate of infinitesimal tool paths. Especially, the fast feedrate optimization is realized by using the Boolean operation based on the Goldfeather CSG rendering algorithm, and the simulation results reveal the availability of the proposed optimization method dramatically reducing the cutting time and/or the optimization time. As a result, the proposed optimization method will go far toward improving the productivity and qualify.

PSIM 소프트웨어에 의한 STATCOM 시스템 시뮬레이션 (STATCOM System Simulation Used by the PSIM Software)

  • 이화수;김용헌;이은웅;이동주
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.94-96
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    • 2003
  • The study for improvement of power qualify is widely performed, because most equipments used semi-conductor are very sensitive for power quality. In this paper, we performed modeling for STATCOM system which developed using SCRs, and suggested the compensation principle of reactive Power by simulations used PSIM software. We will apply this results to 30kVA STATCOM under manufacturing.

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전력품질 변화에 따른 유도전동기의 특성 해석 (The Characteristic Analysis of Induction Motor by Power Quality Variance)

  • 김종겸;이은웅;손홍관;이민명
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 A
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    • pp.137-139
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    • 1998
  • Electrical service faults and momentary voltage variances may result in a costly shutdown. This papers present the degree that power qualify variance have an effect on the performance of induction motor.

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Nd:YAG레이저를 이용한 스텐실 절단공정II -레이저의 공정변수가 스텐실 절단특성에 미치는 영향- (Stencil cutting process by Nd:YAG laser II -Influence of process parameters on cutting characteristics of stencil-)

  • 이제훈;서정;김정오;신동식;이영문
    • 한국레이저가공학회지
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    • 제4권2호
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    • pp.47-57
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    • 2001
  • This study deals with the laser cutting of stencil for the PCB. The most important aim of this study is to determine optimal conditions which make good-qualify stencil in Nd:YAG laser cutting. We made an experiment according to various variables (power. type of mask. gas pressure, cutting speed, and pulse width) and analyzed the cutting characteristics (surface roughness, kerf width. dross) . Each variable has optimal value for good-qualify cut edge under fixed condition. And neural network after learning experimental data with a million time iteration could predict surface roughness of cut edge under arbitrary condition approximately.

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파형 비교를 이용한 데이터 압축 기법 (Data Compression using Waveform Comparison)

  • 성성만;임성일;이승재;배영준;진용우;김정한;김병진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 A
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    • pp.151-153
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    • 2003
  • This paper was studied on using data of the protective relay by Power Quality Monitor. The protective relay will have problem to save data for PQM(Power Qualify Monitoring) analysis because the protective relay memory is limited. So this paper was proposed new data compression of the data was get from the protective relay. The scheme is compared each cycle after DFT(Discrete Fourier Transform). And scheme is verified through simulation of protective relay data was from real distribution system.

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전력계통의 전력품질 외란을 고려한 플리커 평가에 관한 연구 (A Study on Filcker Evaluation Considering Power Quality Disturbance of Power System)

  • 정승복;김재철
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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    • pp.376-379
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    • 2006
  • This paper studies flicker evaluation considering power quality disturbance. A flicker problem with light device irritates human's eyes. Also, the flicker problem has an influence on adverse effect such as rolling device and rotating device. However, a study of flicker evaluation is not complete. A flicker is measured and evaluated at monitoring point. But we consider power qualify disturbances such as voltage sag and transient that cause fault and inverter/breaker switching. Power quality disturbances affects flicker evaluation. A flicker evaluation index increases. Therefore, we consider power quality disturbances. We detect voltage sag and transient using wavelet and evaluate flicker without flicker index including power quality disturbances.

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Global Today - 원자력발전소 저전압 케이블의 노화에 대한 적격, 상태 모니터링 및 관리 (1) (QUALIFICATION, CONDITION MONITORING, AND MANAGEMENT OF AGEING OF LOW VOLTAGE CABLES IN NUCLEAR POWER PLANT)

  • 강기식
    • 전기저널
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    • 통권451호
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    • pp.46-58
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    • 2014
  • 2013년 말, 전세계에 운행중인 원자력발전소 원자로는 434기로 총 용량은 371.6GW(e)이며, 이 중 약 80%는 20년 이상 사용되었다. 많은 회원국들은 최우선 순위로 자신들의 원자력발전소 운행 기간을 원래의 예상 기간인 30~40년 보다 길게 허용했다. 그렇다면 원자력발전소의 어려운 환경에서 기존의 케이블을 어떻게 적격 판정할 것인가. 본 원고는 원자력발전소의 저전압 케이블의 적격, 상태 모니터링 및 관리에 대한 연구 사항을 기술하였다.

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