Teses / dissertações: "Electric power transmission"

1

Shaaban, Mohamed Mohamed Abdel Moneim. "Calculation of available transfer capability of transmission networks including static and dynamic security". Thesis, Click to view the E-thesis via HKUTO, 2002. http://sunzi.lib.hku.hk/hkuto/record/B42576817.

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2

Lee, Cheuk-wing. "Transmission expansion planning in a restructured electricity market". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38959410.

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3

Salem, M. M. "Two level state estimation for large electric power systems". Thesis, University of Strathclyde, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372189.

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4

Yu, Chang. "An investigation of subsynchronous oscillation of AC/DC power systems modeling and analysis /". Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37151885.

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5

Cecchi, Valentina Miu Karen Nan. "A modeling approach for electric power transmission lines in the presence of non-fundamental frequencies/". Philadelphia, Pa. : Drexel University, 2008. http://hdl.handle.net/1860/2583.

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6

Zabel, D. F. "Structure-borne sound transmission within electric power steering systems". Thesis, University of Salford, 2018. http://usir.salford.ac.uk/48186/.

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Transfer path analysis (TPA) is an established and valuable tool in the automotive industry, to determine the contributions of structure-borne sound sources to receiver responses at target positions. The classical TPA approach is based on contact forces at the interface between source and receiver to characterise the dynamic loads induced by the source and frequency response functions (FRFs) to quantify the transfer paths of the sound from the interface locations to the target positions. With knowledge of the determined contributions it is then possible to decide whether source loads or FRFs must be improved to optimise the target quantities. Recently a timesaving improvement to classical TPA has been proposed, where the loads are characterised using the in-situ blocked force method, so that dismantling of source and receiver is not necessary. This method is therefore called in-situ TPA. However, if the contributions of internal structure-borne sound sources to the overall vibro-acoustic behaviour of a product are desired it is of benefit if the target quantities are blocked forces. Thus it would be possible to virtually couple the product with the properties of an overall receiver. Therefore this thesis presents a TPA approach called “blocked force transmissibility transfer path analysis” (bfTPA). In this context, the proposed internal-source-path-receiver-model (ISPRM) poses the theoretical basis of bfTPA. The aim of the presented novel TPA is to determine the contribution of internal structure-borne sound sources to an overall target quantity of a product. The presented approach uses the vector of in-situ blocked forces measured externally at the contact interface of the overall product and a corresponding set of “blocked force transmissibility” (BFT) functions relating the external coupling degrees of freedom (DOFs) to the internal source DOFs in order to propagate the external in-situ blocked forces back to multiple internal in-situ blocked forces. To prove the methodology of the presented approach three case studies, which increase in complexity, were carried out experimentally. The case studies concern a beam and an electric power steering system with paraxial servo unit (EPSapa), respectively. EPSapa systems consist of multiple embedded vibrational components which are defined as “internal sources”. The electric motor, the ball nut assembly and the toothed belt are identified as the main internal sources of an EPSapa system. Hence they are characterised by means of experimentally determined blocked forces. For the determination, micro electro mechanical systems (MEMS) accelerometers are embedded at the so called “internal interfaces”. This poses a novel application of the in-situ method in combination with the dealing of continuous and revolving internal interfaces. Concluding a further application of the bfTPA methodology is presented. It allows the external in-situ blocked forces of EPS systems or other products to be predicted based on internal insitu blocked forces and the BFT functions within internal receivers such as housings, for instance. Hence, the proposed approach is called “virtual component assembly”. It offers the advantage to synthesize a virtual EPS system based on the in-situ blocked forces of its components which are determined on test benches.

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7

Zhang, Xiaodong. "Power system transmission enhancement through storage". Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-11242009-020211/.

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8

Radibratovic, Branislav. "Reactive optimization of transmission and distribution networks". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/28264.

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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Begovic, Miroslav; Committee Member: Divan, Deepakraj; Committee Member: Dorsey, John; Committee Member: Ferri, Bonnie; Committee Member: Lambert, Frank.

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9

Sozer, Sevin Park Chan S. "Transmission expansion planning to alleviate congestion in deregulated power markets". Auburn, Ala., 2006. http://repo.lib.auburn.edu/Send%206-15-07/SOZER_SEVIN_35.pdf.

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10

Yan, Yonghe, e 嚴勇河. "A multi-agent based approach to transmission cost allocation". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B3124256X.

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11

Jayachandran, Krishna K. "STBC-encoded cooperative asynchronous transmissions for transmission energy efficiency". Diss., Online access via UMI:, 2005.

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12

Lee, Cheuk-wing, e 李卓穎. "Transmission expansion planning in a restructured electricity market". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38959410.

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13

Cordero, Roberto. "Estimation of transmission losses in a changing electric power industry". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/39395.

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14

Matevosyan, Julija. "Wind Power Integration in Power Systems with Transmission Bottlenecks". Doctoral thesis, Stockholm, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4108.

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15

Kleinhans, Kevin. "Investigation into possible mechanisms of light pollution flashover of 275kv transmission lines as a cause of unknown outages". Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1071.

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16

Li, Xiaojuan. "Estimations of power system frequency, phasors and their applications for fault location on power transmission lines". University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0125.

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The thesis is devoted to the development of new algorithms for estimation of system frequency, power system phasors and transmission line fault location in the context of power system protection and control. A z-transform signal model combined with a nonlinear post-filtering scheme to estimate the operating frequency in a power system is first developed in the thesis. The signal model parameters are identified by an optimisation method in which the error between the model output and the actual signal that represents a voltage or current in the power system is minimised. The form and the structure of the signal model do not require iterations in the optimisation process for parameter identification. The system operating frequency is directly evaluated from the model parameters. Effects of noise and any frequency components other than the operating or supply-frequency on the accuracy are countered very effectively by applying a median post-filtering on the time series representing the frequency estimates derived from the model. Extensive simulation studies and comparisons with previously-published frequency estimation techniques confirm the high performance of the method developed in the thesis in terms of accuracy and time delay. With respect to power system phasor estimation, a method is developed based on waveform interpolation in the discrete time-domain to counter the spectral leakage errors arising in forming, by discrete Fourier transform (DFT), the supply frequency phasors representing power system voltages and currents when there are system frequency deviations from the nominal value. The interpolation scheme allows DFT evaluation to be performed with a time window length which is exactly equal to the fundamental period of the voltage or current waveform. Comparative studies presented in the thesis confirm the improvements achieved by the method proposed over other previouslypublished techniques in terms of accuracy and computing time. With the availability of accurate operating frequency and phasor estimates, an optimal fault location method based on multi-conductor distributedparameter line model is developed. The method is a general one which is applicable to any transmission line configurations, including multi-terminal lines. The fault location method is based on the minimisation of an objective function in which the fault distance is a variable. The objective function is formed from combining the phase-variable distributed-parameter equations of individual line sections from the fault point to the line terminals. The multivariable minimisation leads to high accuracy and robustness of the fault location algorithm in which any voltage/current measurement errors, including sampling time synchronisation errors, are represented in the estimation procedure as variables in addition to the fault distance. Extensive simulation studies are performed to verify that the method developed is highly accurate and robust. The thesis is supported by two international publications of which the candidate is a joint author.

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17

Wei, Ping. "A comprehensive approach to transmission pricing and its applications /". Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23765926.

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18

Tang, Yousin. "Power system stability in the presence of FACTS elements". Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/13432.

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19

Kalyani, Radha Padma. "A nonlinear optimization approach for UPFC power flow control and voltage security". Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Kalyani_completeThesis_09007dcc80438f59.pdf.

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Thesis (Ph. D.)--University of Missouri--Rolla, 2007.
Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed November 29, 2007) Includes bibliographical references.

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20

Guldbrand, Anna. "Analysis of an induction regulator for power flow control in electric power transmission systems". Thesis, Linköping University, The Department of Physics, Chemistry and Biology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5329.

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Controlling the power flow in transmission systems has recently gained increased interest. The difficulties of building new lines and the pressure of having a high utilization of existing assets, makes the flexibility of grid systems increasingly important.

This master thesis work investigates induction regulators as control devices for active power flow in a transmission system. A small change in angle of the rotor affects both the amplitude and the phase of the voltage. The magnetic coupling in the induction regulator can be controlled by changing the permeability of a thermo magnetic material such as gadolinium and can hence give a second independent controlling parameter. An analytical model and calculations in the

FEM software AceTripleC together with Matlab, is used to simulate the influence of the regulators connected to a simple grid in case1, a 400 kV scenario and case 2, a 45 kV scenario.

The analysis was carried out on a small transmission system consisting of two parallel transmission lines connected to source and load. The induction regulators are connected to one of the parallel transmission lines. The regulators modelled in case 1 must be able to control the active power flow in the regulated line to vary between 50 and 150 % of the original power flow through this line.

This shall be done over a range of 0 to 800 MW transmitted power. The regulators modelled in case 2 must be able to control the active power flow in

the regulated line to vary between 0 and 30 MW, if this does not cause the power flow in the parallel line to exceed 30 MW. This shall be done over a range of 0 to

50 MW transmitted power.

The regulators are designed as small and inexpensive as possible while still fulfilling requirements regarding the active power flow controllability in the grid, current density in windings and maximum flux density in core and gap.

The results indicate that the size of the 400 kV solution has to be reduced to become competitive whereas for the 45 kV solution the relative difference to existing solution is smaller. Advantages with the proposed design over a phase shifting transformer are mainly a simpler winding scheme and the absence of a tap changer.

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21

Setréus, Johan. "On Reliability Methods Quantifying Risks to Transfer Capability in Electric Power Transmission Systems". Licentiate thesis, KTH, Electromagnetic Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10258.

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In the operation, planning and design of the transmission system it is of greatest concern to quantify the reliability security margin to unwanted conditions. The deterministic N-1 criterion has traditionally provided this security margin to reduce the consequences of severe conditions such as widespread blackouts. However, a deterministic criterion does not include the likelihood of different outage events. Moreover, experience from blackouts shows, e.g. in Sweden-Denmark September 2003, that the outages were not captured by the N-1 criterion. The question addressed in this thesis is how this system security margin can be quantified with probabilistic methods. A quantitative measure provides one valuable input to the decision-making process of selecting e.g. system expansions alternatives and maintenance actions in the planning and design phases. It is also beneficial for the operators in the control room to assess the associated security margin of existing and future network conditions.

This thesis presents a method that assesses each component's risk to an insufficient transfer capability in the transmission system. This shows on each component's importance to the system security margin. It provides a systematic analysis and ranking of outage events' risk of overloading critical transfer sections (CTS) in the system. The severity of each critical event is quantified in a risk index based on the likelihood of the event and the consequence of the section's transmission capacity. This enables a comparison of the risk of a frequent outage event with small CTS consequences, with a rare event with large consequences.

The developed approach has been applied for the generally known Roy Billinton Test System (RBTS). The result shows that the ranking of the components is highly dependent on the substation modelling and the studied system load level.

With the restriction of only evaluating the risks to the transfer capability in a few CTSs, the method provides a quantitative ranking of the potential risks to the system security margin at different load levels. Consequently, the developed reliability based approach provides information which could improve the deterministic criterion for transmission system planning.

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22

Westerlund, Per. "Condition measuring and lifetime modelling of electrical power transmission equipment". Licentiate thesis, KTH, Elektroteknisk teori och konstruktion, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-167136.

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The electric grid is important in modern society, so the outages should be few. The transmission grid should have a real high availability, since it transports electrical energy across the country. Then, it is difficult to plan outages for maintenance and installation. This thesis lists twenty surveys about failures of circuit breakers and disconnectors, with data about the cause and the lifetime. It also contains a survey of about forty condition-measuring methods for circuit breakers and disconnectors, mostly applicable to the electric contacts and the mechanical parts. As there is no published method to monitor the electric contacts at voltages around 400 kV, a system with IR sensors has been installed at the nine contacts of six disconnectors. The purpose is to avoid outages for maintenance by estimating the condition of the contacts while the disconnectors are still connected to high voltage. The measured temperatures are collected by radio and regressed against the square of the current, since the best exponent for the current was found to be 2.0. The coefficient of determination $R^2$ is high, greater than 0.9. This gives for each contact a regression coefficient, which can serve as an estimate of the condition of the contact. The higher the coefficient is, the more heat is produced at the contact, which can damage the material. This enables a ranking of the different contacts and shows which the worst ones are. This coefficient can also give a dynamic rating of the disconnector.
Elnätet är viktigt i det moderna samhället, så antalet avbrott bör vara lågt. Särskilt stamnätet bör ha en särskilt hög tillgänglighet, då det transporterar elektrisk energi tvärsöver landet. Då blir det svårt att planera avbrott för underhåll och utbyggnad. Denna avhandling tar upp tjugo studier av fel i brytare och frånskiljare med data om felorsak och livslängd. Den har också en översikt av ett fyrtiotal olika metoder för tillståndsmätningar för brytare och frånskiljare, som huvudsakligen rör de elektriska kontakterna och de mekaniska delarna. Eftersom det inte finns någon beskriven metod för att övervaka elektriska kontakter för spänningar på runt 400 kV, har ett system med IR sensorer installerats på de nio kontakterna på sex frånskiljare. Målet är att minska antalet avbrott för underhåll genom att skatta skicket hos kontakterna, när frånskiljarna fortfarande är kopplade till högspänning. De uppmätta temperaturerna tas emot genom radio och behandlas genom regression mot kvadraten av strömmen, då den bästa exponenten för strömmen visade sig vara 2,0. Förklaringsfaktorn $R^2$ är hög, över 0,9. För varje kontakt ger det en regressionskoefficient, som blir en skattning av kontaktens skick. Ju högre koefficienten är, desto mer värme utvecklas det i kontakten, vilket kan leda till skador på materialet. Kontakternas olika koefficienter ger en rankordning dem och därmed en möjlighet att prioritera vilken frånskiljare som ska underhållas först. Systemet kan också användas för att minska eller öka den tillåtna strömmen baserat på skicket.

QC 20150522

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23

Gopinathan, Muraleedharan 1953. "Incentive structures for electric power transmission investment in a deregulated environment". Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/91780.

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24

LAZARESCU, MIHAI TEODOR. "Electric power quality assessment and data transmission over low voltage mains". Doctoral thesis, Politecnico di Torino, 1998. http://hdl.handle.net/11583/2507488.

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The research presented in this work is directed towards finding and demonstrating the efficiency of two flexible integrated solutions that address the most modern needs in fields like home and industrial automation, domotronic, power consumption remote monitoring and reading, etc. The problem was looked at from two points of view. One that provides a means for quality assessment of electric power distribution and loads, and the other that is directed towards a device for using the low voltage mains as data communication network.

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25

Chan, Morgan Hing-Lap. "Communication channel characteristics and behaviour of intrabuilding power distribution circuits". Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25081.

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Intrabuilding power distribution circuits offer a number of unique advantages for local area networking. To enable the selection of proper error-control codes and protocols for reliable data communication services, error pattern statistics of intrabuilding power line channels are obtained. Also, error-causing disturbances are identified and their relationships to specific types of error patterns are determined. It is found that error occurrence is highly periodic, with periodicity being a function of the power line frequency which is nominally 60Hz in North America. Furthermore, results indicate that error pattern behaviour is relatively insensitive to communication carrier frequency and modulation schemes. Based on the measurement results, hybrid ARQ with bit-interleaving is suggested for reliable data transmission at high data rate (19,200bps). Burst error correcting codes can be used to reduce decoder cost and complexity with some sacrifices in performance. At lower data rates (1,200bps or below), effective error control can be accomplished more easily. Finally, the attenuation characteristics of a number of typical power line channels are presented. It is found that high frequency bypass can be used to improve signal transmission between different phases of the distribution transformer.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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26

Smith, Mark Allen. "Improved dynamic stability using FACTS devices with phasor measurement feedback /". This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-05022009-040702/.

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27

Hasanović, Amer. "A simulation and analysis toolbox for power systems and genetic algorithm based damping controller design". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2173.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains viii, 73 p. : ill. Includes abstract. Includes bibliographical references (p. 71-73).

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28

Kim, Joong-Ho. "Modeling of package and board power distribution networks using transmission matrix and macro-modeling methods". Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/13864.

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29

Miyasaka, Juro. "Study on Microwave-Driven Electric Vehicle for Agriculture". Kyoto University, 2014. http://hdl.handle.net/2433/188749.

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Kyoto University (京都大学)
0048
新制・論文博士
博士(農学)
乙第12823号
論農博第2796号
新制||農||1025(附属図書館)
学位論文||H26||N4818(農学部図書室)
31310
京都大学農学研究科農業工学専攻
(主査)教授清水浩, 教授近藤直, 教授飯田訓久
学位規則第4条第2項該当

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30

Okafor, Chukwuemeka. "Electricity generation, transmission and distribution policy: a comparative study of Nigeria (1960-2011) and South Africa (1960-2011)". Thesis, University of Fort Hare, 2013. http://hdl.handle.net/10353/d1007049.

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The electric power policies in Nigeria and South Africa are considered the governments’ intention to provide quality and affordable electricity to the people. A comparative study on the electric power policies focuses on the similarities and differences in the policy approaches, the policy issues that affect electrification, and the impact of the policy issues in achieving the goal of universal access to quality and affordable electricity power in both countries. The methodological approach allows for an in depth textual study on the electric power policy documents in both countries. In Nigeria, the government intends to address the massive demand-supply imbalance and achieve the goal of electrification through reforms that focus on private sector-led growth in the sub-sector. In South Africa, the identification of electrification as a public problem by the post apartheid government leads to an integrated policy framework that focuses on balancing economic concerns with social and environmental considerations. The study identifies electricity provision as a social welfare responsibility of the governments in both countries and examines the policy issues in the context of public welfare. In Nigeria, the policy issues are found to be self serving and not in line with sustainable public interest, given the socio-economic challenges. As a result they, exert less impact on achieving the goal of universal access to quality and affordable electricity in the country. In South Africa, good governance in the sub-sector has enabled the identification of policy issues in line with sustainable public interests of social equity, poverty alleviation and environmental sustainability; and government using public administration agencies to play a key role in service delivery. Recommendations of the study mainly derive from the South African experience on electrification, and are intended to offer some policy-lessons to Nigeria in the sub-sector. The study contributes to new knowledge in the discipline of public administration by opening up new vistas for a comparative analysis of electric power policy issues in both countries in the context of public welfare. Besides, a comparative study on electrification in Nigeria and South Africa from a policy angle contributes to the existing knowledge base in the discipline.

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31

Kirby, Chris. "Generation participation factors and transmission costing". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0029/MQ47426.pdf.

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32

Eriksson, Robert. "Security-centered Coordinated Control in AC/DC Transmission Systems". Licentiate thesis, Stockholm : Royal Institute of Technology, 2008. http://kth.diva-portal.org/smash/record.jsf?searchId=4&pid=diva2:101.

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33

Perninge, Magnus. "Modeling the Uncertainties Involved in Net Transmission Capacity Calculation". Licentiate thesis, Stockholm : Skolan för elektro- och systemteknik, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10392.

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34

Sternberger, Ronny. "Analytical modelling and controller design of a multilevel STATCOM". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25797.

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35

Jones, Peter Gibson. "Evaluation of Voltage Instability Countermeasures in Constrained Sub-transmission Power Networks". PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/112.

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This paper investigates the various parameters that effect voltage stability in sub-transmission power networks. The paper first looks at contributions from equipment: generators, transmission lines, transformers, capacitors, SVCs and STATCOMs. The paper also looks at the effects of loads on voltage stability. Power flow solutions, PV and VQ curves are covered. The study models an existing voltage problem i.e., a long, radial, 115 kV sub-transmission network that serves a 65 MW load. The network model is simulated with the following voltage instability countermeasures: adding a capacitor, adding an SVC, adding a STATCOM, tying to a neighboring transmission system, adding generation and bringing in a new 230 kV source. Then, using the WECC heavy-winter 2012 power flow base case and Siemens PTI software, VQ and PV curves are created for each solution. Finally, the curves are analyzed to determine the best solution.

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36

Teru, Agboola Awolola. "Efficient rectenna circuits for microwave wireless power transmission". Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/481.

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Miniaturisation has been the holy grail of mobile technology. The ability to move around with our gadgets, especially the ones for communication and entertainment, has been what semiconductor scientists have battled over the past decades. Miniaturisation brings about reduced consumption in power and ease of mobility. However, the main impediment to untethered mobility of our gadgets has been the lack of unlimited power supply. The battery had filled this gap for some time, but due to the increased functionalities of these mobile gadgets, increasing the battery capacity would increase the weight of the device considerably that it would eventually become too heavy to carry around. Moreover, the fact that these batteries need to be recharged means we are still not completely free of power cords. The advent of low powered micro-controllers and sensors has created a huge industry for more powerful devices that consume a lot less power. These devices have encouraged hardware designers to reduce the power consumption of the gadgets. This has encouraged the idea of wireless power transmission on another level. With lots of radio frequency energy all around us, from our cordless phones to the numerous mobile cell sites there has not been a better time to delve more into research on WPT. This study looks at the feasibilities of WPT in small device applications where very low power is consumed to carry out some important functionality. The work done here compared two rectifying circuits’ efficiencies and ways to improve on the overall efficiencies. The results obtained show that the full wave rectifier would be the better option when designing a WPT system as more power can be drawn from the rectenna. The load also had a great role as this determined the amount of power drawn from the circuitry.

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37

Leedy, Aleck Wayne Nelms R. M. "Analysis of DC power systems containing induction motor-drive loads". Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Spring/doctoral/LEEDY_ALECK_32.pdf.

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38

Toh, Leng Huei. "A follow-up study on wireless power transmission for unmanned air vechicles [sic vehicles]". Thesis, Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Dec%5FToh.pdf.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2007.
Thesis Advisor(s): Jenn, David C. "December 2007." Description based on title screen as viewed on January 24, 2008. Includes bibliographical references (p. 85-88). Also available in print.

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39

Hasanovic, Azra. "Modeling and control of the unified power flow controller (UPFC)". Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1633.

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Thesis (M.S.)--West Virginia University, 2000.
Title from document title page. Document formatted into pages; contains viii, 78 p. : ill. Includes abstract. Includes bibliographical references (p. 61-63).

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Yu, Chang, e 余暢. "An investigation of subsynchronous oscillation of AC/DC power systems: modeling and analysis". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37151885.

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Tomiyama, Elias Kento 1981. "Estudo do aspecto locacional da alocação de custos da transmissão = Study of the locational aspect in the transmission cost allocation problem". [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/262018.

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Orientador: Carlos Alberto de Castro Júnior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
Made available in DSpace on 2018-08-21T03:54:49Z (GMT). No. of bitstreams: 1 Tomiyama_EliasKento_M.pdf: 3080864 bytes, checksum: 7293fe7b3271c5c27e9b967c48a4e245 (MD5) Previous issue date: 2012
Resumo: Esta dissertação de mestrado apresenta quatro metodologias de alocação de custos da transmissão: Pro rata (PR), Divisão Proporcional (PS), Zbus-médio (Zbus_AVG) e Nodal. Enquanto a primeira desconsidera o aspecto locacional e aloca os custos baseado apenas na quantidade de potência produzida pelos geradores e consumida pelas cargas, as últimas três levam em conta este aspecto, ou seja, as tarifas pagas por geradores e cargas dependem do seu ponto de conexão na rede elétrica. Através de simulações computacionais são levantadas várias situações de operação no sentido de avaliar a influência e as possíveis implicações de ordem regulatória, política, econômica e social de um país provocadas pela inclusão do aspecto locacional na definição das tarifas de uso do sistema de transmissão. Por fim, mostra-se a possibilidade de se considerar as tarifas pagas pelos agentes do sistema como um critério de decisão a mais no problema do planejamento da expansão da transmissão
Abstract: This dissertation describes four transmission cost allocation methodologies: Pro rata (PR), Proportional sharing (PS), Zbus-average (Zbus_AVG) and Nodal. While the first one disregards the locational aspect and allocates costs based only on the amount of power delivered by generators and consumed by loads, the last three ones take this aspect into account, i.e. charges are dependent on where generators and demands are connected in the network. Several computer simulations were made in order to assess the influence of the locational aspect into transmission pricing scheme and the results were used for a critical analysis, including political, regulatory, economic and social aspects. Finally, we discuss the possibility of using the fees paid by transmission system agents as an additional criterion for the Transmission Expansion Planning problem
Mestrado
Energia Eletrica
Mestre em Engenharia Elétrica

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Kumbale, Murali. "Bulk transmission system reliability analysis of protection and control groups". Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/13840.

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Kundy, Beda Jerome. "Probabilistic analytical methods for evaluating MV distribution networks including voltage regulating devices". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52414.

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Thesis (PhD)--Stellenbosch University, 2001.
ENGLISH ABSTRACT: Accurate load models are required for the computation of load flows in MV distribution networks. Modem microprocessors in recent times enable researchers to sample and log domestic loads. The findings show that they are stochastic in nature and are best described by a beta probability distribution. . In rural areas two different load types may be present. Such loads are domestic and pump loads, the latter may be modelled as constant P - Q loads. An analytical tool for computing voltage regulation on MV distribution networks for rural areas feeding the mentioned loads is therefore required. The statistical evaluation of the consumer voltages requires a description of load currents at the time of the system maximum demand. To obtain overall consumer voltages at any specified risk for the two types of the loads, the principle of superposition is adopted. The present work deals with conventional 22kV three-phase distribution (te:. - te:.) connected networks as used by ESKOM, South Africa. As the result of the connected load, MV networks can experience poor voltage regulation. To solve the problem of voltage regulation, voltage regulators are employed. The voltage regulators considered are step-voltage regulators, capacitors and USE (Universal Semiconductor Electrification) devices. USE devices can compensate for the voltage drops of up to 35% along the MV distribution network, thus the criteria for the application of the USE devices is also investigated. The load currents are treated as signals when assessing the cost of distribution system over a period of time due to power losses. The individual load current signal is modelled by its mean and standard deviation. The analytical work for developing general expressions of the total real and total imaginary components of branch voltage drops and line power losses in single and three-phase networks without branches are presented. To deal with beta-distributed currents on MV distribution networks, new scaling factors are evaluated at each node. These new scaling factors are derived from the distribution transformer turns ratio and the deterministic component of the statistically distributed load currents treated as constant real power loads. In the case of an individual load current signal, the transformation ratio is evaluated from the distribution transformer turns ratio and the average value of the· signal treated as constant real power load. The evaluation of the consumer voltage percentile values can be accurately evaluated up to 35% voltage drop. This is possible by the application of the expanded Taylor series, using the first three terms. The coefficients of these three terms were obtained using a search engine imbedded in the probabilistic load flow. The general expressions for evaluating the overall consumer voltages due to statistical and non-statistical loads currents are also given. These non-statistical currents may be due to constant P - Q loads, line capacitance and the modeling of voltage regulators. The Newton-Raphson algorithm is applied to perform a deterministic load flow on singlephase networks. A backward and forward sweep algorithm is applied to perform a deterministic load flow on single and three-phase systems. A new procedure for modelling step-voltage regulators in three-phase (te:. - te:.) connected networks is outlined. Specifying a transformation ratio of 1.1 and 1.15 respectively, identifies the open-delta or closed-delta configuration for three-phase networks. The algorithms and the developed general expressions for single and three-phase networks without branches are presented in this work. A new algorithm is developed to enable the developed general expressions to be applied to practical MV distribution networks. The algorithms were tested for their accuracy by comparing the analytical results with Monte Carlo simulation and they compared well. An illustrative example to show the application of the present work on a practical MY distribution networks is presented. A criterion for the application of the USE devices is outlined. It is anticipated that, the work presented in this thesis will be invaluable to those involved in the design of MY distribution systems in developing countries.
AFRIKAANSE OPSOMMING: Akkurate lasrnodelle word benodig vir drywingsvloei analises in MV distribusiestelsels. As gevolg van nuwe digitale verwerkers is dit deesdae moontlik om huishoudelike laste te monitor. Die lasdata dui daarop dat laste stochasties is en kan met behulp van die Beta verdeling beskryf word. In landelike gebiede is daar twee tipes laste. Hulle is eendersyds huishoudelike laste en andersyds pomp-tipe laste wat as konstante P-Q laste beskou kan word. Dit is dus belangrik om toepaslike analitiese metodes te gebruik om die spanningsvalle by hierdie laste te bereken met inagname van die las-tipes. By die statistiese berekening van die verbruiker se spanning moet 'n statistiese model van die lasstroom verskaf word op die tydstip van maksimum aanvraag. Daarna moet die prinsiep van superposissie gebruik word om die spannings by verskeie nodes by 'n gespesifiseerde vertrouensinterval te bepaal. Hierdie proefskrif is gebaseer op konvensionele 22kV, drie fase distribusie (delta na delta) netwerke, soos deur Eskom, Suid Afrika gebruik. Hierdie stelsels ondervind dikwels nadelige spanningsvlakke en spanningsreëlaars word derhalwe aangewend. Hierdie reëlaars is gewoonlik van tap-tipe of daar kan ook gebruik gemaak word van kapasitore en ook elektroniese reëlaars soos die USE tipe toestelle. Laasgenoemde kan op LV vir spanningsvalle tot 35% kompenseer. In hierdie werk word die werkdrywing verliese in die geleiers bereken met behulp 'n seinmodel van die lasstrome. Die individuele lasstrome word by wyse van gemiddeldes en variasies beskryf. Om die algemene algoritmes vir die berekening van die reële en imaginêre spanningsvalle, asook die verliese in enkelfase en driefase stelsels daar te stel word aanvanklik gebruik gemaak van stelsels sonder vertakkings. Om die statistiese lasbeskrywing op die laagspanningskant na die MV vlak oor te dra word van nuwe skaalfaktore gebruik gemaak. Hierdie faktore word bereken op die basis van die transformator se verhouding en die deterministiese komponent van die statistiese verspreide lasstrome, as konstante reële drywingslaste beskou. Met die ontwikkelde metode kan die verbruiker se spanning by 'n gegewe vertrouensinterval akkuraat bereken word vir spanningsvalle tot 35%. Dit word moontlik gemaak deur die Taylor-reeks tot drie terme toe te pas. Daar moet egter gebruik gemaak word van toepaslike koëffisiënte wat bepaal word deur 'n geprogrammeerde soektog. 'n Algemene stel vergelykings om die spanning by enige verbruiker te bereken, ongeag die topologie van die netwerk, word ook gegee. Die Newton-Raphson metode word aangewend om die deterministiese drywingsvloei op enkelfase stelsels te bereken. A truwaartse-voorwaartse metode is gebruik om die drywingsvloei te bepaal vir driefase stelsels. 'n Nuwe prosedure is ontwikkel vir die modellering van die spanningsreëlaars in driefase, delta-delta netwerke. Deur gebruik te maak van 'n transformatorverhouding van 1.1 of 1.15 kan die oop-delta of toe-delta netwerke voorgestel word. 'n Nuwe algoritme is ontwikkelom multi-vertakkings in 'n netwerk te hanteer. Al die prosedures is deeglik met behulp van Monte Carlo simulasies getoets en die resultate is heel bevredigend. Om die metodes te illustreer word 'n gevallestudie ingesluit waar die metodes gebruik word om 'n netwerk te evalueer met en sonder die sogenaamde USE toestelle. Kriteria vir die aanwending van hierdie toerusting word voorgestel. Daar word verwag dat die werk soos in hierdie proefskrifuiteengesit is die ontwerp van MV distribusiestelsels, veral in ontwikkelende lande, heelwat sal verbeter.

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Ferreira, Kurt Josef. "Fault location for power transmission systems using magnetic field sensing coils". Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-050707-120755/.

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Naredo, V. José Luis A. "Communication frequency response of high voltage power lines". Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26725.

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Several methods for calculating the electrical phase and modal parameters of overhead transmission lines are described in this thesis; then, a graphical method for evaluating communication frequency response of delta transmission lines -based on the guidelines given by W. H. Senn [12,13,14]- is developed. The graphical method, combined with the parameters calculation methods, obviates the need of large mainframe computers for the analysis of power line carrier (PLC) systems. A new technique for assessing coupling alternatives, based on Senn's method, is developed. The technique is applied to generate coupling recommendations; it is found that many of the current recommendations given elsewhere [21] are not reliable. Finally, future work to be done in this field is proposed.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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Susuki, Yoshihiko. "Ｔransient Dynamics and Stability Boundaries in Electric Power System with DC Transmission". 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/77775.

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Ng, Kwok-kei Simon. "A game-theoretic study of the strategic interaction between transmission and generation expansion planning in a restructured electricity market". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39343534.

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Li, Quan. "AC loss characteristics of monolayer and multilayer superconducting power transmission cables". Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609500.

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Liu, Kai. "A decentralized congestion management approach for the multilateral energy transaction via optimal resource allocation". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38750107.

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Crnojacki, Zorica. "Extra high voltage transmission corridor siting : technical, public, institutional and regulatory considerations /". Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-10032007-171749/.

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