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You searched for subject:(transmission line faults). Showing records 1 – 3 of 3 total matches.

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University of Adelaide

1. Rohadi, Nanang. Global sensitivity analysis of impedance measurement algorithms implememented in intelligent electronic devices.

Degree: 2013, University of Adelaide

A novel methodology for testing performance of impedance measurement algorithms used in transmission line protection schemes is developed. Nowadays, impedance measurement algorithms are software functions implemented in the multifunction Intelligence Electronic Devices (IEDs) responsible for overall monitoring, protection and control of transmission lines. Accurate impedance measurement during fault conditions is the key in successful performance of the line protection as well as fault location functions of an IED. This thesis investigates a typical practical situation where only short-term fault records of voltage and current measurements from one side of a transmission line are used as inputs in the impedance measurement algorithm. Current flowing into the fault from the remote terminal of transmission line as well as fault impedance can influence significantly accuracy of impedance measurement. Since these two quantities are not measured, we require a systematic tool which will assess sensitivity of impedance measurement to those factors. At present, these sensitivities are obtained in heuristic and ad hoc manner during application testing done by utilities before commissioning of new IEDs. Situation in practice can be increasingly complex and this kind of unsystematic testing approach can fail. The thesis addresses those practical complex cases in the systematic manner. In these cases we encounter the following configurations of transmission lines with new not measured factors: - parallel closely spaced lines, where the effect of electromagnetic mutual coupling can be significant; - series capacitive compensation of transmission line, where capacitance of the compensation device can be unknown; - three-terminal lines, where measurements on the tapped line are not available. The proposed systematic sensitivity testing tool comprises of a transmission line electromagnetic simulation module and a Global Sensitivity Analysis (GSA) module. The software packages commonly used by industry are employed to implement those modules: the DIgSILENT software for the line simulation module and the SIMLAB software for the GSA module. The simulation module is used to simulate large number of fault scenarios for all samples in the factor space, while the GSA module is responsible for creating a set of specific samples in the factor space as well as for sensitivity analysis. The commercial multifunctional IED SEL-421 from the Schweitezer Engineering Laboratories has been used to demonstrate the proposed sensitivity analysis tool. The IED functions has been modelled in DIgSILENT environment and integrated into the simulation module. Test automation program has been written using the DIgSILENT Programming Language (DPL) so fully automatic and integrated performance of the simulation and the GSA modules has been achieved. The GSA module relies on the Quasi-Monte Carlo (QMC) technique with the Sobol’s quasi random sampling and the Morris method is used in fast factor pre-screening in order to remove non-influential factors before… Advisors/Committee Members: Zivanovic, Rastko (advisor), School of Electrical and Electronic Engineering (school).

Subjects/Keywords: Global Sensitivity Analysis; transmission line faults; distance protection; impedance measurement algorithms

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Rohadi, N. (2013). Global sensitivity analysis of impedance measurement algorithms implememented in intelligent electronic devices. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/84961

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Rohadi, Nanang. “Global sensitivity analysis of impedance measurement algorithms implememented in intelligent electronic devices.” 2013. Thesis, University of Adelaide. Accessed November 20, 2019. http://hdl.handle.net/2440/84961.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Rohadi, Nanang. “Global sensitivity analysis of impedance measurement algorithms implememented in intelligent electronic devices.” 2013. Web. 20 Nov 2019.

Vancouver:

Rohadi N. Global sensitivity analysis of impedance measurement algorithms implememented in intelligent electronic devices. [Internet] [Thesis]. University of Adelaide; 2013. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/2440/84961.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rohadi N. Global sensitivity analysis of impedance measurement algorithms implememented in intelligent electronic devices. [Thesis]. University of Adelaide; 2013. Available from: http://hdl.handle.net/2440/84961

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Manet, Anthony. Etude de défauts non francs sur des câbles en vue du diagnostic : Soft defects diagnosis in coaxial transmission lines.

Degree: Docteur es, Electronique, Optronique et Systèmes, 2016, Université Paris-Est

La détection des défauts non francs est un passage obligé dans la gestion de la maintenance des câbles (Wire Health Monitoring) et permet d’anticiper l’apparition de défauts francs engendrés par l'aggravation de défauts non francs. Ces travaux de thèse visent à étudier la problématique de défauts non francs dans les câbles électriques. L'étude proposée consiste à étudier le problème direct : modélisation électromagnétique et compréhension des phénomènes physiques liés à la présence des défauts non francs, et impact des défauts sur leurs signatures obtenues par réflectométrie. Il est proposé dans ce travail de caractériser des défauts non francs représentatifs de situations réelles, ce qui peut servir ultérieurement dans la résolution du problème inverse : déterminer la localisation et la sévérité des défauts à partir du réflectogramme en vue du diagnostic. L'approche proposée se fait en deux temps. Dans un premier temps, une caractérisation électromagnétique d’une zone localisée d’un câble présentant un défaut non franc est réalisée grâce à une modélisation électromagnétique prenant en compte la géométrie tridimensionnelle du défaut. Deux méthodes numériques ont été exploitées : une méthode de différences finies dans le domaine temporel (FDTD) et une méthode de Galerkin discontinu. Les résultats des simulations permettent d'exprimer les perturbations engendrées par le défaut et de déduire leur influence sur la propagation des signaux dans le câble. Des validations expérimentales menées dans le domaine temporel et le domaine fréquentiel permettent de confronter les mesures aux prédictions numériques. Dans un deuxième temps, des modèles électriques de défauts sont exprimés sous forme de paramètres localisés R, L, C, et G qui peuvent être utilisés dans un modèle de ligne de transmission. Une telle analyse des défauts non francs permet de relier une faible variation locale des caractéristiques physiques et électriques de la ligne à une variation des signaux de réflectométrie et des paramètres électriques de la ligne. L’approche permet de fournir des informations utiles pour caractériser des défauts et peut ainsi contribuer à améliorer les performances des systèmes de détection

The soft fault detection feature is certainly a very important aspect of wire health monitoring and an important process required in electrical wiring system operation. It has a great influence on the security and quality of supply. In transmission line networks, this feature is needed to provide a timely identification of the faulted line thus anticipating the appearance of severe faults that are initially caused by soft fault degradation. This work focuses on soft fault problems in electrical fault diagnosis and their weak impact on coaxial transmission lines. The objective of this work is to carry out a soft fault forward model: electromagnetic modeling and investigating the behavior of the line after soft damages and then to analyze its effects on their signatures obtained by reflectometry. It is proposed in this work to characterize the…

Advisors/Committee Members: Picon, Odile (thesis director).

Subjects/Keywords: Lignes de transmission; Simulation numérique; Diagnostic filaire; Défaut non franc; Détection de défaut; Transmission line; Numerical simulation; Wire faults; Soft fault; Fault detection

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Manet, A. (2016). Etude de défauts non francs sur des câbles en vue du diagnostic : Soft defects diagnosis in coaxial transmission lines. (Doctoral Dissertation). Université Paris-Est. Retrieved from http://www.theses.fr/2016PESC1054

Chicago Manual of Style (16th Edition):

Manet, Anthony. “Etude de défauts non francs sur des câbles en vue du diagnostic : Soft defects diagnosis in coaxial transmission lines.” 2016. Doctoral Dissertation, Université Paris-Est. Accessed November 20, 2019. http://www.theses.fr/2016PESC1054.

MLA Handbook (7th Edition):

Manet, Anthony. “Etude de défauts non francs sur des câbles en vue du diagnostic : Soft defects diagnosis in coaxial transmission lines.” 2016. Web. 20 Nov 2019.

Vancouver:

Manet A. Etude de défauts non francs sur des câbles en vue du diagnostic : Soft defects diagnosis in coaxial transmission lines. [Internet] [Doctoral dissertation]. Université Paris-Est; 2016. [cited 2019 Nov 20]. Available from: http://www.theses.fr/2016PESC1054.

Council of Science Editors:

Manet A. Etude de défauts non francs sur des câbles en vue du diagnostic : Soft defects diagnosis in coaxial transmission lines. [Doctoral Dissertation]. Université Paris-Est; 2016. Available from: http://www.theses.fr/2016PESC1054

3. Das, Swagata. Fault location and analysis in transmission and distribution networks.

Degree: PhD, Electrical and Computer Engineering, 2015, University of Texas – Austin

Short-circuit faults are inevitable on transmission and distribution networks. In an effort to provide system operators with an accurate location estimate and reduce service restoration times, several impedance-based fault location algorithms have been developed for transmission and distribution networks. Each algorithm has specific input data requirements and make certain assumptions that may or may not hold true in a particular scenario. Identifying the best fault location approach, therefore, requires a thorough understanding of the working principle behind each algorithm. Moreover, impedance-based fault location algorithms require voltage and current phasors, captured by intelligent electronic devices (IEDs), to estimate the fault location. Unfortunately, voltage phasors are not always available due to operational constraints or equipment failure. Furthermore, impedance-based fault location algorithms assume a radial distribution feeder. With increased interconnection of distributed generators (DGs) to the feeder, this assumption is violated. DGs also contribute to the fault and severely compromise the accuracy of location estimates. In addition, the variability of certain DGs such as the fixed-speed wind turbine can alter fault current levels and result in relay misoperations. Finally, data recorded by IEDs during a fault contain a wealth of information and are prime for use in other applications that improve power system reliability. Based on the above background, the first objective of this dissertation is to present a comprehensive theory of impedance-based fault location algorithms. The contributions lie in clearly specifying the input data requirement of each algorithm and identifying their strengths and weaknesses. The following criteria are recommended for selecting the most suitable fault location algorithm: (a) data availability and (b) application scenario. The second objective is to develop fault location algorithms that use only the current to estimate the fault location. The simple but powerful algorithms allow system operators to locate faults even in the absence of voltage data. The third objective is to investigate the shortcomings of existing fault location algorithms when DGs are interconnected to the distribution feeder and develop an improved solution. A novel algorithm is proposed that require only the voltage and current phasors at the substation, is straightforward to implement, and is capable of locating all fault types. The fourth objective is to examine the effects of wind speed variation on the maximum and minimum fault current levels of a wind turbine and investigate the impact on relay settings. Contributions include developing an accurate time-domain model of a fixed-speed wind turbine with tower shadow and wind shear and verifying that the variation in wind speed does not violate relay settings calculated using the IEC 60909-0 Standard. The final objective is to exploit intelligent electronic device data for improving power system reliability. Contributions include validating the… Advisors/Committee Members: Santoso, Surya (advisor), Baldick, Ross (committee member), Becker, Michael F. (committee member), Hersh, Matt (committee member), Short, Thomas A. (committee member).

Subjects/Keywords: Fault location; One-ended impedance-based methods; Two-ended impedance-based methods; Intelligent electronic devices; Power system faults; Power system reliability; Power quality; Event report analysis; Relay settings; Transmission line measurements; Distribution measurements; Impedance-measurement

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Das, S. (2015). Fault location and analysis in transmission and distribution networks. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/47202

Chicago Manual of Style (16th Edition):

Das, Swagata. “Fault location and analysis in transmission and distribution networks.” 2015. Doctoral Dissertation, University of Texas – Austin. Accessed November 20, 2019. http://hdl.handle.net/2152/47202.

MLA Handbook (7th Edition):

Das, Swagata. “Fault location and analysis in transmission and distribution networks.” 2015. Web. 20 Nov 2019.

Vancouver:

Das S. Fault location and analysis in transmission and distribution networks. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2015. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/2152/47202.

Council of Science Editors:

Das S. Fault location and analysis in transmission and distribution networks. [Doctoral Dissertation]. University of Texas – Austin; 2015. Available from: http://hdl.handle.net/2152/47202

.