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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Über eine methode zur behandlung unsymmetrischer Kabelsysteme unter berücksichtigung des konzentrischen mit Bleimantel umpressten Zwei-leiter-kabels als beispiel ...

Geldermann, Arthur. January 1906 (has links)
Inaug.-diss.--Königlich technischen Hochschule in Danzig.
2

Advanced techniques application of on-line partial discharge detection in power cables

Zhang, Hao, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW January 2006 (has links)
Large numbers of installed medium or high voltage power cables are now of advanced age and have gradual insulation deterioration problems. On-line Partial Discharge (PD) measurement has inherent advantages over the conventional off-line measurement, but it also suffers from a very significant Electro-Magnetic Interference (EMI) problem due to the small PD signal levels being monitored. The large magnitude EMI signal often completely swamps the smaller magnitude PD signal, making it difficult to monitor anything but extremely large PD activity. To monitor cable condition and to be able to assess insulation degradation trends requires advanced techniques. In this thesis, the issues of sensor selection, digital filtering, software based on-line differential technique and wavelet Transform (WT) de-noising techniques are studied. Their applicability, advantages and limitations are discussed with the simulation and high voltage measurement results. The High Frequency Current Transformer (HFCT) type PD sensor is selected after being compared with other sensor in term of sensitivity, universal applicability, frequency response and the installation difficulty. The sinusoidal noise frequency identification and application of the conventional digital filtering are studied. The Least Mean Square (LMS) and Recursive Least Square (RLS) algorithm digital adaptive filters are compared in detail and RLS adaptive filter is selected. Wavelet transform de-noising technique for on-line PD measurement is carefully studied and the applications of noise reduction are developed. A novel WT threshold value selection algorithm is presented in this thesis. The new WT algorithm is compared with the existing wavelet techniques using numerical simulation and laboratory high voltage testing data on cables. The results show that this new fully automatic WT de-noising method has achieved great progress with the capability of detection 30 pC PD signal during on-site on-line measurement where typical noise level is ten times higher in magnitude. On the basis of traditional off-line differential or balanced detection circuit, a software based on-line differential technique is proposed in this thesis. The novel method developed has the capability to process one whole AC cycle of PD data. It enables traditional q-?? and n-?? distributions to be obtained as well as PD repetition rates and the usual integrated PD parameters. These techniques are developed for the on-site on-line PD measurement in power cables, but they are not limited to cables. They can also be applied to other high voltage equipment with minor or without modification in the data acquisition procedure.
3

Analysis of the radial temperature gradient in uninsulated electric conductors

Collins, Stuart S. 08 1900 (has links)
No description available.
4

Calculation of an effective thermal conductivity for electric power cables buried in a non-homogeneous environment

Saleeby, Kary Eugene 08 1900 (has links)
No description available.
5

International ampacity model based on IEC 287 standard

Engelkemier, Douglas G. 08 1900 (has links)
No description available.
6

Development of procedures and equipment for after laying tests on HV extruded dielectric cables /

Jimenea, Arturo P. Unknown Date (has links)
Thesis (MEng in Electrical Engineering)--University of South Australia, 1996
7

Advanced techniques application of on-line partial discharge detection in power cables

Zhang, Hao, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW January 2006 (has links)
Large numbers of installed medium or high voltage power cables are now of advanced age and have gradual insulation deterioration problems. On-line Partial Discharge (PD) measurement has inherent advantages over the conventional off-line measurement, but it also suffers from a very significant Electro-Magnetic Interference (EMI) problem due to the small PD signal levels being monitored. The large magnitude EMI signal often completely swamps the smaller magnitude PD signal, making it difficult to monitor anything but extremely large PD activity. To monitor cable condition and to be able to assess insulation degradation trends requires advanced techniques. In this thesis, the issues of sensor selection, digital filtering, software based on-line differential technique and wavelet Transform (WT) de-noising techniques are studied. Their applicability, advantages and limitations are discussed with the simulation and high voltage measurement results. The High Frequency Current Transformer (HFCT) type PD sensor is selected after being compared with other sensor in term of sensitivity, universal applicability, frequency response and the installation difficulty. The sinusoidal noise frequency identification and application of the conventional digital filtering are studied. The Least Mean Square (LMS) and Recursive Least Square (RLS) algorithm digital adaptive filters are compared in detail and RLS adaptive filter is selected. Wavelet transform de-noising technique for on-line PD measurement is carefully studied and the applications of noise reduction are developed. A novel WT threshold value selection algorithm is presented in this thesis. The new WT algorithm is compared with the existing wavelet techniques using numerical simulation and laboratory high voltage testing data on cables. The results show that this new fully automatic WT de-noising method has achieved great progress with the capability of detection 30 pC PD signal during on-site on-line measurement where typical noise level is ten times higher in magnitude. On the basis of traditional off-line differential or balanced detection circuit, a software based on-line differential technique is proposed in this thesis. The novel method developed has the capability to process one whole AC cycle of PD data. It enables traditional q-?? and n-?? distributions to be obtained as well as PD repetition rates and the usual integrated PD parameters. These techniques are developed for the on-site on-line PD measurement in power cables, but they are not limited to cables. They can also be applied to other high voltage equipment with minor or without modification in the data acquisition procedure.
8

Analysis of electric fields in power cables /

Cheng, Fai-chut. January 1989 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1990.
9

Characterization of real power cable defects by diagnostic measurements

Hernández Mejía, Jean Carlos. January 2008 (has links)
Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Dr. Ronald Harley; Committee Member: Dr. John Buck; Committee Member: Dr. Miroslav Begovic; Committee Member: Dr. Nigel Hampton; Committee Member: Dr. Rhett Mayor. Part of the SMARTech Electronic Thesis and Dissertation Collection.
10

Electrical parameters in multi-strand superconducting cables and their effect on stability

Lu, Bing. Luongo, Cesar A. January 2006 (has links)
Thesis (Ph. D.)--Florida State University, 2006. / Advisor: Cesar Luongo, Florida State University, FAMU-FSU College of Engineering, Dept. of Mechanical Engineering. Title and description from dissertation home page (viewed July 28, 2006). Document formatted into pages; contains xiii, 126 pages. Includes bibliographical references.

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