Faulted Feeder Identification Based on Active Adjustment of Arc Suppression Coil and Similarity Measure of Zero-Sequence Currents

As for the wide application of arc suppression coil to the grounding in neutral point of mine high voltage grid, grid leakage fault rules and harmonic characteristics of the neutral point grounding system through arc suppression coil are analyzed, the selective leakage protection program “zero-sequence voltage starts, fifth harmonics of grid zerosequence voltage and zero-sequence current are extracted for phase comparison” is proposed, and corresponding fifth harmonic extraction circuit and power direction discrimination circuit are designed. The experimental results show that the protective principle applies not only to the neutral point insulated power supply system, but also to the power supply system in which neutral point passes arc suppression coil, which can solve selective leakage protection problems under different neutral grounding ways, improving the reliability of selective leakage and guaranteeing the stability of the action value.

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The Research Based on Zero Sequence Energy to the Line Selection in Distribution Network

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.614-615.846 ◽

2012 ◽

Vol 614-615 ◽

pp. 846-849

Author(s):

Shu Tian ◽

Jin Peng He ◽

Yu Zheng

Keyword(s):

Single Phase ◽

Distribution Network ◽

Power Network ◽

Fault Line ◽

Ground Fault ◽

Arc Suppression Coil ◽

Zero Sequence ◽

Line Selection ◽

Fault Lines ◽

Resistance Component

When single phase-to-ground fault happened in power network with arc suppression coil grounded, capacitor current through fault point is compensated and reduced by installing arc suppression coil. Zero-sequence current’s amplitude and phase of fault lines and sound lines are so similar that it increases the difficulty of selecting the fault line. But the resistance component of zero sequence current has no relationship with the arc extinguishing coil compensation, absolute value of resistance component to the fault lines show the maximum, and zero sequence current’s polarity of fault lines is contrary to sound lines. In this paper, because of the characteristic of resistance component, a method is put forward based on zero sequence energy to the line selection in distribution network, it import auto-reclosing techniques into the line selection. The principle is verified by MATLAB simulator. It has high accuracy to select the fault line with this method.

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Leakage Failure and Principle of Underground Low Voltage Grid

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.214.254 ◽

2012 ◽

Vol 214 ◽

pp. 254-258

Author(s):

Jun Mei Geng ◽

Chun Guang Li

Keyword(s):

Low Voltage ◽

Leakage Detection ◽

Grounding System ◽

Arc Suppression Coil ◽

Detection Program ◽

Three Phase ◽

Zero Sequence ◽

Power Direction ◽

Leakage Failure ◽

Zero Sequence Voltage

To describe the leakage protection of underground low voltage grid are based on zero-sequence voltage and zero sequence power direction of the current leakage protection and earth leakage protection based on the additional DC power supply two kinds. The paper gives the theoretical analysis of these two kinds of leakage, and unified the three-phase neutral point grounding system and by arc suppression coil grounding the under compensation leakage detection program, that provides a new approach for underground leakage detection.

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Locating Method of Single-Phase Grounding Fault in Small Current Grounding System Based on Distribution Automation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.321-324.1423 ◽

2013 ◽

Vol 321-324 ◽

pp. 1423-1428

Author(s):

Jun Zhou ◽

Ke Zheng Cao

Keyword(s):

Single Phase ◽

System Modeling ◽

Simulation Method ◽

Neutral Point ◽

Distribution Automation ◽

Fault Line ◽

Small Current ◽

Grounding System ◽

Arc Suppression Coil ◽

Zero Sequence

In case of the arc suppression coil for neutral point grounding of small current grounding system, when single-phase grounding fault occurs, due to the arc suppression coil for fault line of the compensation effect of the zero sequence current, the fault features is not obvious, it can't implement the fault line selection and fault point location. This paper puts forward a method of change fault lines zero sequence current shortly, namely a resistance inductance (RL) series branch parallel in arc suppression coil, the series branch acts on the system shortly and changes arc suppression coil compensation degree temporarily in single-phase grounding fault. The change of zero sequence residual current only appears the loop from the neutral point to the fault point via the fault line, using FTU (feeder terminal units) on lines monitor the change of zero sequence current on each nodes for fault regional location. And prove this theory the feasibility of the by using MATLAB software of system modeling simulation method.

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The Study of Fault Location Method Based on FTU Feeder Automation Technology

The Open Electrical & Electronic Engineering Journal ◽

10.2174/1874129001307010143 ◽

2013 ◽

Vol 7 (1) ◽

pp. 143-148

Author(s):

Zhou Jun ◽

Cao Ke-Zheng ◽

Zheng Hong-Xia

Keyword(s):

Power Distribution ◽

Fault Location ◽

Single Phase ◽

Automation System ◽

Fault Line ◽

Feeder Automation ◽

Grounding System ◽

Arc Suppression Coil ◽

Zero Sequence ◽

Automation Technology

With the development of power distribution automation system, feeder automation technology in the small current grounding system single-phase grounding fault location plays an important role. In the neutral arc suppression coil grounding system, because of the compensation effect of arc suppression coil, the system fault feature is not obvious. This paper puts forward a method of RL series branch parallel in arc suppression coil, when system single-phase grounding fault occurs, the series branch switch gets closed and acts on the neutral, that changes the compensation degree of arc suppression coil to zero sequence current in fault line, the change of zero sequence residual current being the biggest in the fault section from neutral to fault point. FTU is used to monitor the change in each fault line for fault regional location.

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Faulty Line Selection Method Based on Comprehensive Dynamic Time Warping Distance in a Flexible Grounding System

Energies ◽

10.3390/en15020471 ◽

2022 ◽

Vol 15 (2) ◽

pp. 471

Author(s):

Yu He ◽

Xinhui Zhang ◽

Wenhao Wu ◽

Jun Zhang ◽

Wenyuan Bai ◽

...

Keyword(s):

Dynamic Time Warping ◽

Selection Method ◽

Time Warping ◽

Grounding System ◽

Ground Fault ◽

Maximum Value ◽

Arc Suppression Coil ◽

Zero Sequence ◽

Line Selection ◽

Dynamic Time

A flexible grounding system is a system in which the neutral point of the power supply is grounded via the arc suppression coil in parallel with a low-resistance resistor. When operating normally or a temporary ground fault occurs, the arc suppression coil is used for grounding, whereas the small resistance is switched on when a permanent ground fault occurs. At present, the problem of low protection sensitivity when a high-resistance ground fault occurs in a flexible grounding system has not been solved yet. According to the characteristics of low waveform similarity between the faulty line and the non-faulty line when a single-phase grounding fault occurred, a new faulty line selection method based on a combination of Dynamic Time Warping (DTW) distance and the transient projection method is proposed in this paper. Firstly, the fault transient signal is extracted by a digital filter as a basis for faulty line selection. Secondly, the transient zero-sequence current of each line is projected onto the busbar transient zero-sequence voltage, and the projected DTW distance of each line is calculated. Finally, according to the calculation formula of waveform comprehensive similarity coefficient, the Comprehensive DTW (CDTW) distance is obtained, and the top three CDTW distance values are selected to determine the faulty line. If the maximum value is greater than the sum of the other two CDTW distance values, the line corresponding to the maximum value is judged as the faulty line; otherwise, it is judged as a busbar fault. The simulation results based on MATLAB/Simulink and field data test show that the method can accurately determine the faulty line under diverse fault conditions.

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Handling WSD using Hierarchical Clustering Algorithm with sentences

International Journal of Scientific Research in Science Engineering and Technology ◽

10.32628/ijsrset1841120 ◽

2018 ◽

pp. 83-88

Author(s):

Mohana Priya K ◽

Pooja Ragavi S ◽

Krishna Priya G

Keyword(s):

Hierarchical Clustering ◽

Similarity Measure ◽

Clustering Algorithm ◽

Clustering Algorithms ◽

Cosine Similarity Measure ◽

Hierarchical Clustering Algorithm ◽

Multiple Levels ◽

Pos Tagger ◽

Sentence Clustering ◽

The Right

Clustering is the process of grouping objects into subsets that have meaning in the context of a particular problem. It does not rely on predefined classes. It is referred to as an unsupervised learning method because no information is provided about the "right answer" for any of the objects. Many clustering algorithms have been proposed and are used based on different applications. Sentence clustering is one of best clustering technique. Hierarchical Clustering Algorithm is applied for multiple levels for accuracy. For tagging purpose POS tagger, porter stemmer is used. WordNet dictionary is utilized for determining the similarity by invoking the Jiang Conrath and Cosine similarity measure. Grouping is performed with respect to the highest similarity measure value with a mean threshold. This paper incorporates many parameters for finding similarity between words. In order to identify the disambiguated words, the sense identification is performed for the adjectives and comparison is performed. semcor and machine learning datasets are employed. On comparing with previous results for WSD, our work has improvised a lot which gives a percentage of 91.2%

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