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Optimal capacitor placement to minimise harmonics in power systems and software tools

Harmonics in power systems is a relatively new area of research. In view of this and the growing awareness of the quality of the electricity supply, the theory of harmonics in power systems is reviewed. The sources and the effects of harmonics are investigated. The algorithms that are used for the f...

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Main Author: Hitzeroth, Helmuth Victor
Other Authors: Petroianu, Alexander
Format: Thesis
Language:English
Published: Department of Electrical Engineering 2016
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access_status_str Open Access
author Hitzeroth, Helmuth Victor
author2 Petroianu, Alexander
author_browse Hitzeroth, Helmuth Victor
Petroianu, Alexander
author_facet Petroianu, Alexander
Hitzeroth, Helmuth Victor
author_sort Hitzeroth, Helmuth Victor
collection Thesis
description Harmonics in power systems is a relatively new area of research. In view of this and the growing awareness of the quality of the electricity supply, the theory of harmonics in power systems is reviewed. The sources and the effects of harmonics are investigated. The algorithms that are used for the frequency analysis of power systems are investigated and compared. These algorithms comprise the companion circuit method, the Gauss-Seidel method, the Newton-Raphson method and the current injection method. In addition various freely and commercially available software packages for the harmonic analysis of power systems are studied and compared. For this purpose a questionnaire was sent out to software developers and suppliers. This questionnaire as well as the results of the comparative investigation are presented. A power system has many configurations due to the switching of power capacitors on to and off the power grid. Some of these configurations can result in unacceptable distortion levels. An existing state space method is investigated to analyse these configurations and an example is worked through, to illustrate how this method works. However, this state space model is only applicable to radial power systems and there have to be power capacitors at the end of every feeder amongst others. Because of these significant disadvantages of this method, a new analytical approach or theoretical foundation for the analysis of power capacitors in radial as well as meshed power systems is developed in this thesis. For this purpose the branch current and nodal voltage equations are determined. Redundant nodal voltages are eliminated from the set of branch current equations. The remaining equations and the nodal voltage equations are then combined to form a system realisation. This system realisation is still overspecified and a further reduction is done to obtain a minimal realisation of the power system. This approach is demonstrated analytically and numerically by way of five case studies. This approach is also verified by comparing it with the current injection method. Identical results are obtained with the state space approach and with the current injection method, demonstrating that the state space approach is indeed valid.
format Thesis
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institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:33:26.520Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2016
publishDateRange 2016
publishDateSort 2016
publisher Department of Electrical Engineering
publisherStr Department of Electrical Engineering
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source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/19678 Optimal capacitor placement to minimise harmonics in power systems and software tools Hitzeroth, Helmuth Victor Petroianu, Alexander Electrical Engineering Harmonics in power systems is a relatively new area of research. In view of this and the growing awareness of the quality of the electricity supply, the theory of harmonics in power systems is reviewed. The sources and the effects of harmonics are investigated. The algorithms that are used for the frequency analysis of power systems are investigated and compared. These algorithms comprise the companion circuit method, the Gauss-Seidel method, the Newton-Raphson method and the current injection method. In addition various freely and commercially available software packages for the harmonic analysis of power systems are studied and compared. For this purpose a questionnaire was sent out to software developers and suppliers. This questionnaire as well as the results of the comparative investigation are presented. A power system has many configurations due to the switching of power capacitors on to and off the power grid. Some of these configurations can result in unacceptable distortion levels. An existing state space method is investigated to analyse these configurations and an example is worked through, to illustrate how this method works. However, this state space model is only applicable to radial power systems and there have to be power capacitors at the end of every feeder amongst others. Because of these significant disadvantages of this method, a new analytical approach or theoretical foundation for the analysis of power capacitors in radial as well as meshed power systems is developed in this thesis. For this purpose the branch current and nodal voltage equations are determined. Redundant nodal voltages are eliminated from the set of branch current equations. The remaining equations and the nodal voltage equations are then combined to form a system realisation. This system realisation is still overspecified and a further reduction is done to obtain a minimal realisation of the power system. This approach is demonstrated analytically and numerically by way of five case studies. This approach is also verified by comparing it with the current injection method. Identical results are obtained with the state space approach and with the current injection method, demonstrating that the state space approach is indeed valid. 2016-05-16T11:50:34Z 2016-05-16T11:50:34Z 1996 Master Thesis Masters MSc (Eng) http://hdl.handle.net/11427/19678 eng application/pdf Department of Electrical Engineering Faculty of Engineering and the Built Environment University of Cape Town
spellingShingle Electrical Engineering
Hitzeroth, Helmuth Victor
Optimal capacitor placement to minimise harmonics in power systems and software tools
thesis_degree_str Master's
title Optimal capacitor placement to minimise harmonics in power systems and software tools
title_full Optimal capacitor placement to minimise harmonics in power systems and software tools
title_fullStr Optimal capacitor placement to minimise harmonics in power systems and software tools
title_full_unstemmed Optimal capacitor placement to minimise harmonics in power systems and software tools
title_short Optimal capacitor placement to minimise harmonics in power systems and software tools
title_sort optimal capacitor placement to minimise harmonics in power systems and software tools
topic Electrical Engineering
url http://hdl.handle.net/11427/19678
work_keys_str_mv AT hitzerothhelmuthvictor optimalcapacitorplacementtominimiseharmonicsinpowersystemsandsoftwaretools