• 제목/요약/키워드: Internal Winding Fault

검색결과 36건 처리시간 0.022초

발전기시스템의 고정자보호 IED를 위한 개선된 알고리즘 (Advanced Algorithm for IED of Stator Winding Protection of Generator System)

  • 박철원
    • 전기학회논문지P
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    • 제57권2호
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    • pp.91-95
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    • 2008
  • The large AC generator fault may lead to large impacts or perturbations in power system. The generator protection control systems in Korea have been imported and operated through a turn-key from overseas entirely. Therefore a study of the generator protection field has in urgent need for a stable operation of the imported goods. In present, the algorithm using the current ratio differential relaying based DFT for stator winding protection or a fault detection had been applied that of internal fault protection of a generator. the DFT used for the analysis of transient state signal conventionally had defects losing a time information in the course of transforming a target signal to frequency domain. In this paper, the discrete wavelet transform (DWT) was applied a fault detection of the generator being superior to a transient state signal analysis and being easy to real time realization. The fault signals after executing a terminal fault modeling collect using a MATLAB package, and calculate the wavelet coefficients through the process of a muiti-level decomposition (MLD). The proposed algorithm for a fault detection using the Daubechies WT (wavelet transform) was executed with a C language and the commend line function for the real time realization after analyzing MATLAB's graphical interface. The advanced technique had improved faster a speed of fault discrimination than a conventional DFR based on DFT.

뉴로-퍼지를 이용한 변기 보호 알고리즘 (Protective Algorithm for Transformer Using Nuro-Fuzzy)

  • 이명윤;이종범;홍동석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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    • pp.299-302
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    • 2002
  • The second harmonic component is commonly used for blocking differential relay in Power transformers. However it is difficult to distinguish between inrush and internal winding fault with differential current protective relaying. This paper proposed a new method using nuro-fuzzy. The used data in nuro-fuzzy algorithm are 3-phase primary voltage and fundamental harmonic of differential current. Various states of transformer are simulated using BCTRAN and HYSDAT of EMTP. As a result of applying the algorithm in various cases, the correct discrimination between internal winding fault and inrush performed.

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웨이블렛 변환을 이용한 변압기 보호계전 알고리즘 개발 (The Development of Protective Relaying Algorithm for Transformer Based on Wavelet Transform)

  • 홍동석;정채균;이종범
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 A
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    • pp.485-487
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    • 2001
  • Current differential protective relaying with harmonic restraint module is, in general, used to protect transformer. But It is hard to distinguish inrush and internal winding fault with differential current protective relaying. This paper presents the new protective algorithm for transformers using 3-phase differential current's d1 coefficient values in wavelet transform. Various states of transformer was simulated using EMTP. Internal winding fault and inrush are classified within shorter time using the proposed algorithm.

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HCM기반 뉴로-교지 시스템을 이용한 변압기 보호 알고리즘 (Protecive Algorithm for Transformer Using Nuro-Fuzzy System based on HCM)

  • 이명윤;이종범
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 A
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    • pp.552-554
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    • 2003
  • The second harmonic component is commonly used for blocking differential relay in power transformers. However, it is difficult to distinguish between inrush and internal winding fault with differential current protective relaying. This paper proposed a new method using Nuro-Fuzzy System based on HCM(Hard C-Means). The proposed system is more objective and systematic than existing model. The data used in input are 3-phase primary voltage and fundamental harmonic of differential current. Various states of transformer are simulated using BCTRAN and HYSDAT of EMTP. As a result of the application of algorithm in various cases, the exact discrimination between internal winding fault and inrush is performed.

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Internal Fault Classification in Transformer Windings using Combination of Discrete Wavelet-Transforms and Back-propagation Neural Networks

  • Ngaopitakkul Atthapol;Kunakorn Anantawat
    • International Journal of Control, Automation, and Systems
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    • 제4권3호
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    • pp.365-371
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    • 2006
  • This paper presents an algorithm based on a combination of Discrete Wavelet Transforms and neural networks for detection and classification of internal faults in a two-winding three-phase transformer. Fault conditions of the transformer are simulated using ATP/EMTP in order to obtain current signals. The training process for the neural network and fault diagnosis decision are implemented using toolboxes on MATLAB/Simulink. Various cases and fault types based on Thailand electricity transmission and distribution systems are studied to verify the validity of the algorithm. It is found that the proposed method gives a satisfactory accuracy, and will be particularly useful in a development of a modern differential relay for a transformer protection scheme.

고압전동기 결함신호의 특징추출에 관한 연구 (Feature Extraction for Fault Signals of High Voltage Motor Stator Windings)

  • 박재준;김희동
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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    • pp.1154-1157
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    • 2004
  • During normal machine operation, partial discharge(PD) measurements were performed with turbine generator analyzer(TGA) in imitation stator winding of high voltage motors. The motor was energized to 4.47kV, 6.67, respectively. Applied voltage to Imitation winding was used two voltage level, 4.47[KV]and 6.67[KV]. Motors having imitation stator winding were installed with 80pF capacitive couplers at the terminal box Case of PD Pattern regarding applied voltage phase angel, the PD patterns were displayed two dimensional and three dimensional. TGA summarizes each plot with two quantities such as the normalized quantity number(NQN) and the peak PD magnitude(Qm). As the result, we could discrimidate using TGA the difference of internal and surface discharge for imitation stator winding. We have used the other technique, in order to feature extraction of faulty signals on stator winding, Daubechies Discrete wavelet transform and Harmonics analysis(FFT) about faulty signals.

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웨이브렛 변환 기반 뉴로-펴지를 이용한 변압기 보호계전 알고리즘 (Protective Relaying Algorithm for Transformer Using Neuro-Fuzzy based on Wavelet Transform)

  • 이종범;이명윤
    • 대한전기학회논문지:전력기술부문A
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    • 제54권5호
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    • pp.242-250
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    • 2005
  • This paper proposes a new protective relaying algorithm using Neuro-Fuzzy and wavelet transform. To organize advanced nuero-fuzzy algorithm, it is important to select target data reflecting various transformer transient states. These data are made of changing-rates of Dl coefficient and RSM value within half cycle after fault occurrence. Subsequently, advanced neuro-fuzzy algorithm is obtained by converging the target data. As a result of applying the advanced neuro-fuzzy algorithm, discrimination between internal fault and inrush is correctly distinguished within 1/2 after fault occurrence. Accordingly, it is evaluated that the proposed algorithm can effectively protect a transformer by correcting discrimination between winding fault and inrushing state.

차동전류의 변화율을 이용한 변압기의 여자돌입과 내부사고 구분 알고리즘 (A Discriminating Algorithm between Magnetizing Inrush and Internal Faults of Transformers Using Difference of a differential current)

  • 강용철;이병은;윤재성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
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    • pp.171-173
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    • 2000
  • This paper presents a discriminating algorithm between magnetizing inrush and internal faults of transformers using difference of a differential current. Incase of inrush, change of magnetizing inductance repeats. Thus, second difference of differential current periodically shows pulse while periodic pulse is not represented in case of internal winding fault. The proposed algorithm is suitable irrespective of the amount of remanent flux.

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PSCAD를 이용한 전력용 변압기 모델링과 과도 해석 (Power Transformer Modeling and Transient Analysis using PSCAD)

  • 박철원
    • 전기학회논문지P
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    • 제65권2호
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    • pp.122-129
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    • 2016
  • Current differential protection relaying with second harmonic restraint is the main protection for large capacity power transformer. PSCAD simulation program is widely used for modeling of dynamic varying transients phenomena. This paper deals with a power transformer model and transients analysis using PSCAD software to develop IED for power transformer. Simulation was carried out using a three phase 40MVA, 154/22.9kV, 60Hz, two-winding transformer with Y-Y connection used in actual fields. The paper analyzed transformer magnetizing inrush, external fault, and internal fault conditions with this model in the time domain. In addition, we performed an analysis in the frequency domain using FFT during several conditions.

폴리머 피뢰기의 모듈 설계 및 성능에 관한 연구 (A Study on Module Design and Performance of Polymer Arrester)

  • 조한구;천종욱;강영길
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마연구회
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    • pp.108-111
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    • 2003
  • The main objective of this paper is to module design and pressure relief test a new type of polymer gapless surge arrester for power distribution line. Metal oxide surge arrester for most electric power system applications, power distribution line and electric train are now being used extensively to protect overvoltage due to lightning. Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. When breakdown of gapless elements in a surge arrester occurs due to flashover, fault short current flows through the arrester and internal pressure of the arrester rises. The pressure rise can usually be limited by fitting a pressure relief diaphragm and transferring the arc from the inside to the outside of the housing. However, there is possibility of porcelain fragmentation caused by the thermal shock, pressure rise, etc. Non-fragmenting of the housing is the most desired way to prevent damage to other equipment. The pressure change which is occurred by flashover become discharge energy. This discharge energy raises to damage arrester housing and arrester housing is dispersed as small fragment. Therefore, the pressure relief design is requested to obstruct housing dispersion.

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