27,923 research outputs found

    A Review of Fault Diagnosing Methods in Power Transmission Systems

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    Transient stability is important in power systems. Disturbances like faults need to be segregated to restore transient stability. A comprehensive review of fault diagnosing methods in the power transmission system is presented in this paper. Typically, voltage and current samples are deployed for analysis. Three tasks/topics; fault detection, classification, and location are presented separately to convey a more logical and comprehensive understanding of the concepts. Feature extractions, transformations with dimensionality reduction methods are discussed. Fault classification and location techniques largely use artificial intelligence (AI) and signal processing methods. After the discussion of overall methods and concepts, advancements and future aspects are discussed. Generalized strengths and weaknesses of different AI and machine learning-based algorithms are assessed. A comparison of different fault detection, classification, and location methods is also presented considering features, inputs, complexity, system used and results. This paper may serve as a guideline for the researchers to understand different methods and techniques in this field

    Certainty of outlier and boundary points processing in data mining

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    Data certainty is one of the issues in the real-world applications which is caused by unwanted noise in data. Recently, more attentions have been paid to overcome this problem. We proposed a new method based on neutrosophic set (NS) theory to detect boundary and outlier points as challenging points in clustering methods. Generally, firstly, a certainty value is assigned to data points based on the proposed definition in NS. Then, certainty set is presented for the proposed cost function in NS domain by considering a set of main clusters and noise cluster. After that, the proposed cost function is minimized by gradient descent method. Data points are clustered based on their membership degrees. Outlier points are assigned to noise cluster and boundary points are assigned to main clusters with almost same membership degrees. To show the effectiveness of the proposed method, two types of datasets including 3 datasets in Scatter type and 4 datasets in UCI type are used. Results demonstrate that the proposed cost function handles boundary and outlier points with more accurate membership degrees and outperforms existing state of the art clustering methods.Comment: Conference Paper, 6 page

    Enhancement of dronogram aid to visual interpretation of target objects via intuitionistic fuzzy hesitant sets

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    In this paper, we address the hesitant information in enhancement task often caused by differences in image contrast. Enhancement approaches generally use certain filters which generate artifacts or are unable to recover all the objects details in images. Typically, the contrast of an image quantifies a unique ratio between the amounts of black and white through a single pixel. However, contrast is better represented by a group of pix- els. We have proposed a novel image enhancement scheme based on intuitionistic hesi- tant fuzzy sets (IHFSs) for drone images (dronogram) to facilitate better interpretations of target objects. First, a given dronogram is divided into foreground and background areas based on an estimated threshold from which the proposed model measures the amount of black/white intensity levels. Next, we fuzzify both of them and determine the hesitant score indicated by the distance between the two areas for each point in the fuzzy plane. Finally, a hyperbolic operator is adopted for each membership grade to improve the pho- tographic quality leading to enhanced results via defuzzification. The proposed method is tested on a large drone image database. Results demonstrate better contrast enhancement, improved visual quality, and better recognition compared to the state-of-the-art methods.Web of Science500866

    Unbalanced load flow with hybrid wavelet transform and support vector machine based Error-Correcting Output Codes for power quality disturbances classification including wind energy

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    Purpose. The most common methods to designa multiclass classification consist to determine a set of binary classifiers and to combine them. In this paper support vector machine with Error-Correcting Output Codes (ECOC-SVM) classifier is proposed to classify and characterize the power qualitydisturbances such as harmonic distortion,voltage sag, and voltage swell include wind farms generator in power transmission systems. Firstly three phases unbalanced load flow analysis is executed to calculate difference electric network characteristics, levels of voltage, active and reactive power. After, discrete wavelet transform is combined with the probabilistic ECOC-SVM model to construct the classifier. Finally, the ECOC-SVM classifies and identifies the disturbance type according tothe energy deviation of the discrete wavelet transform. The proposedmethod gives satisfactory accuracy with 99.2% compared with well known methods and shows that each power quality disturbances has specific deviations from the pure sinusoidal waveform,this is good at recognizing and specifies the type of disturbance generated from the wind power generator.НаиболСС распространСнныС ΠΌΠ΅Ρ‚ΠΎΠ΄Ρ‹ построСния ΠΌΡƒΠ»ΡŒΡ‚ΠΈΠΊΠ»Π°ΡΡΠΎΠ²ΠΎΠΉ классификации Π·Π°ΠΊΠ»ΡŽΡ‡Π°ΡŽΡ‚ΡΡ Π² ΠΎΠΏΡ€Π΅Π΄Π΅Π»Π΅Π½ΠΈΠΈ Π½Π°Π±ΠΎΡ€Π° Π΄Π²ΠΎΠΈΡ‡Π½Ρ‹Ρ… классификаторов ΠΈ ΠΈΡ… объСдинСнии. Π’ Π΄Π°Π½Π½ΠΎΠΉ ΡΡ‚Π°Ρ‚ΡŒΠ΅ ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½Π° машина ΠΎΠΏΠΎΡ€Π½Ρ‹Ρ… Π²Π΅ΠΊΡ‚ΠΎΡ€ΠΎΠ² с классификатором Π²Ρ‹Ρ…ΠΎΠ΄Π½Ρ‹Ρ… ΠΊΠΎΠ΄ΠΎΠ² исправлСния ошибок(ECOC-SVM) с Ρ†Π΅Π»ΡŒΡŽ ΠΊΠ»Π°ΡΡΠΈΡ„ΠΈΡ†ΠΈΡ€ΠΎΠ²Π°Ρ‚ΡŒ ΠΈ Ρ…Π°Ρ€Π°ΠΊΡ‚Π΅Ρ€ΠΈΠ·ΠΎΠ²Π°Ρ‚ΡŒ Ρ‚Π°ΠΊΠΈΠ΅ Π½Π°Ρ€ΡƒΡˆΠ΅Π½ΠΈΡ качСства элСктроэнСргии, ΠΊΠ°ΠΊ гармоничСскиС искаТСния, ΠΏΠ°Π΄Π΅Π½ΠΈΠ΅ напряТСния ΠΈ скачок напряТСния, Π²ΠΊΠ»ΡŽΡ‡Π°Ρ Π³Π΅Π½Π΅Ρ€Π°Ρ‚ΠΎΡ€ Π²Π΅Ρ‚Ρ€ΠΎΠ²Ρ‹Ρ… элСктростанций Π² систСмах ΠΏΠ΅Ρ€Π΅Π΄Π°Ρ‡ΠΈ элСктроэнСргии. Π‘Π½Π°Ρ‡Π°Π»Π° выполняСтся Π°Π½Π°Π»ΠΈΠ· ΠΏΠΎΡ‚ΠΎΠΊΠ° нСсиммСтричной Π½Π°Π³Ρ€ΡƒΠ·ΠΊΠΈ Ρ‚Ρ€Π΅Ρ… Ρ„Π°Π· для расчСта разностных характСристик элСктричСской сСти, ΡƒΡ€ΠΎΠ²Π½Π΅ΠΉ напряТСния, Π°ΠΊΡ‚ΠΈΠ²Π½ΠΎΠΉ ΠΈ Ρ€Π΅Π°ΠΊΡ‚ΠΈΠ²Π½ΠΎΠΉ мощности. ПослС этого дискрСтноС Π²Π΅ΠΉΠ²Π»Π΅Ρ‚-ΠΏΡ€Π΅ΠΎΠ±Ρ€Π°Π·ΠΎΠ²Π°Π½ΠΈΠ΅ ΠΎΠ±ΡŠΠ΅Π΄ΠΈΠ½ΡΠ΅Ρ‚ΡΡ с вСроятностной модСлью ECOC-SVM для построСния классификатора. НаконСц, ECOC-SVM классифицируСт ΠΈ ΠΈΠ΄Π΅Π½Ρ‚ΠΈΡ„ΠΈΡ†ΠΈΡ€ΡƒΠ΅Ρ‚ Ρ‚ΠΈΠΏ возмущСния Π² соотвСтствии с ΠΎΡ‚ΠΊΠ»ΠΎΠ½Π΅Π½ΠΈΠ΅ΠΌ энСргии дискрСтного Π²Π΅ΠΉΠ²Π»Π΅Ρ‚-прСобразования. ΠŸΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½Π½Ρ‹ΠΉ ΠΌΠ΅Ρ‚ΠΎΠ΄ Π΄Π°Π΅Ρ‚ ΡƒΠ΄ΠΎΠ²Π»Π΅Ρ‚Π²ΠΎΡ€ΠΈΡ‚Π΅Π»ΡŒΠ½ΡƒΡŽ Ρ‚ΠΎΡ‡Π½ΠΎΡΡ‚ΡŒ 99,2% ΠΏΠΎ ΡΡ€Π°Π²Π½Π΅Π½ΠΈΡŽ с Ρ…ΠΎΡ€ΠΎΡˆΠΎ извСстными ΠΌΠ΅Ρ‚ΠΎΠ΄Π°ΠΌΠΈ ΠΈ ΠΏΠΎΠΊΠ°Π·Ρ‹Π²Π°Π΅Ρ‚, Ρ‡Ρ‚ΠΎ ΠΊΠ°ΠΆΠ΄ΠΎΠ΅ Π½Π°Ρ€ΡƒΡˆΠ΅Π½ΠΈΠ΅ качСства элСктроэнСргии ΠΈΠΌΠ΅Π΅Ρ‚ ΠΎΠΏΡ€Π΅Π΄Π΅Π»Π΅Π½Π½Ρ‹Π΅ отклонСния ΠΎΡ‚ чисто ΡΠΈΠ½ΡƒΡΠΎΠΈΠ΄Π°Π»ΡŒΠ½ΠΎΠΉ Ρ„ΠΎΡ€ΠΌΡ‹ Π²ΠΎΠ»Π½Ρ‹, Ρ‡Ρ‚ΠΎ способствуСт Ρ€Π°ΡΠΏΠΎΠ·Π½Π°Π²Π°Π½ΠΈΡŽ ΠΈ ΠΎΠΏΡ€Π΅Π΄Π΅Π»Π΅Π½ΠΈΡŽ Ρ‚ΠΈΠΏΠ° возмущСния, Π³Π΅Π½Π΅Ρ€ΠΈΡ€ΡƒΠ΅ΠΌΠΎΠ³ΠΎ Π²Π΅Ρ‚Ρ€ΠΎΠ²Ρ‹ΠΌ Π³Π΅Π½Π΅Ρ€Π°Ρ‚ΠΎΡ€ΠΎΠΌ
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