• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1363-1365
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• 1999

This paper Presents an algorithm for the computation of fault location for a transmission line by means of the voltage and current signals. It is impossible to calculate the accurate fault distance, because of the fault resistance and fault current which are unknown. All Currents in the lines are divided by the current distribution factor, so the fault current through the fault resistance can be represented by using data from one terminal of transmission line. This algorithm proposed can calculate the fault distance with only the faulty phase information.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2570-2575
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• 2003

Monitoring a power transmission line is significant for power electric companies. In this paper, we propose a new method for detecting an fault point of power transmission line by use of M-sequence correlation technique. In this method, detecting signal is used as one or plural M-sequences ( same characteristic polynomial, including normal and reverse mark, synchronized ). In receiving point, we make same sequence with the input one and take crosscorrelation function between M-sequence and the received signal. We can see transfer fanctions of plural paths between inputs and a output taps separated from different of delay times on the crosscorrelation function, and from these transfer fanctions, so we compare them when fault occurred with in usual.

• 조명전기설비학회논문지
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• 제28권4호
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• pp.36-41
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• 2014

Most faults that occur on transmission lines are caused by extreme weather with lightning storms in the distance. These are not only prolongs the time of removing and recovering, but also increases economical damages. If faults can be precisely located, maintenance crews can reach them quickly, and remove the faults in time. So, the precise locating of the faulted point on a transmission line is very important to improve the system reliability, and decreases economic damages as an inherent consequence of long term outages. Also, fault location methods are becoming of much importance for utilities and research. In this paper, two single-terminal impedance-based fault location techniques will be investigated to show the reliability and evaluated the performance of reactance and Takagi method by using MATHCAD program simulations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1376-1378
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• 1999

Most conventional protection relays are based on processing information in the spectrum that is close to or at power frequency. It is, however, widely known that faults on transmission lines produce frequency components of a wide range In this respect, this paper describes the basis of a Protection technique for transmission lines which utilises high-frequency components. Fault-generated signals caused by post-fault and the signal derived from stack tuner is connected to the coupling capacitor of CVT. Digital signal processing is then applied to the captured information to determine whether the fault is inside or outside the Protected zone, and to discriminate the fault type on transmission line.

• 대한전기학회논문지:전력기술부문A
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• 제52권1호
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• pp.29-35
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• 2003

This paper presents a fault location algorithm when there are parallel circuits in power system networks. In transmission networks, a fault location method using the distribution factor of fault currents is introduced and in distribution networks a method using direct 3-phase circuit analysis is developed, because the distribution networks are unbalanced. The effect of parallel circuits in fault location is studied in this paper. The effect is important for the range of protecting zones of distance relay in transmission networks and fault location in distribution networks. The result of developed fault location algorithm shows high accuracy in the simulation that using the EMTP.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1543-1544
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• 2008

In this paper, we introduce a gaussian enveloped linear chirp signal that can change parameters for consideration of target material characteristics. Using the gaussian enveloped linear chirp signal, time-frequency domain reflectomety is able to detect fault location in power transmission line. we suggest design method of reference signal for power transmission line fault detection. This method is verified by locating fault in HIV low voltage power transmission line.

• 대한전기학회논문지:전력기술부문A
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• 제48권12호
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• pp.1492-1497
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• 1999

High impedance fault(HIF) is defined as fault the general overcurrent relay can not detect or interrupt. Especially when HIF occur in residential areas, energized high voltage conductor results in fire hazard, equipment damage or personal threat. This paper proposes the model of the high impedance fault in transmission line using the ZnO arrester and resistance to be implemented within EMTP. The performance of the proposed model is tested on a typical 154[kV] korean transmission line system under various fault conditions. Wavelet transform is efficient and useful for the detection of high impedance fault in power system, because it uses variable windows according to frequency. In this paper, HIF detection method using wavelet transform can distinguish HIF form similar fault like arcfurance load, capacitor bank switching and line switching.

• Journal of Electrical Engineering and Technology
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• 제12권6호
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• pp.2106-2117
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• 2017

An effective statistical feature extraction approach of data sampling of fault in the combined transmission system is presented in this paper. The proposed algorithm leads to high accuracy at minimum cost to predict fault location and fault type classification. This algorithm requires impedance measurement data from one end of the transmission line. Modal decomposition is used to extract positive sequence impedance. Then, the fault signal is decomposed by using discrete wavelet transform. Statistical sampling is used to extract appropriate fault features as benchmark of decomposed signal to train classifier. Support Vector Machine (SVM) is used to illustrate the performance of statistical sampling performance. The overall time of sampling is not exceeding 1 1/4 cycles, taking into account the interval time. The proposed method takes two steps of sampling. The first step takes 3/4 cycle of during-fault and the second step takes 1/4 cycle of post fault impedance. The interval time between the two steps is assumed to be 1/4 cycle. Extensive studies using MATLAB software show accurate fault location estimation and fault type classification of the proposed method. The classifier result is presented and compared with well-established travelling wave methods and the performance of the algorithms are analyzed and discussed.

• Journal of Electrical Engineering and Technology
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• 제3권4호
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• pp.460-467
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• 2008

This paper presents a new numerical algorithm for the fault location estimation and arcing fault detection when a single-phase arcing ground fault occurs on a transmission line. The proposed algorithm derived in the spectrum domain is based on the synchronized voltage and current samples measured from the PMUs(Phasor Measurement Units) installed at both ends of the transmission lines. In this paper, the algorithm uses DFT(Discrete Fourier Transform) for estimation. The algorithm uses a short data window for real-time transmission line protection. Also, from the calculated arc voltage amplitude, a decision can be made whether the fault is permanent or transient. The proposed algorithm is tested through computer simulation to show its effectiveness.

• 한국초전도ㆍ저온공학회논문지
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• 제1권1호
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• pp.28-32
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• 1999

We have performed an EMTDC simulation for the current limiting effects of a superconducting fault current limiter (SFCL). The fault currents in the 154 kV transmission line between the arbitrary S1 and S2 substations increased up to 54 KA and 60 KA during the line-to-line and three phase faults, respectively. The SFCL with 100$\omega$ of resistance after quench limited the currents to less than 17 KA within a half cycle. This limited current is well below the upper limit of a circuit breaker, suggesting that the resistance of the SFCL in the transmission line is sufficient.