Dissertations / Theses on the topic 'Electric power consumption Measurement'

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1

Svensson, André. "Atmospheric measurement using CanSat : Sensors power analysis." Thesis, Mittuniversitetet, Institutionen för elektronikkonstruktion, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-39601.

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The climate change has been an ongoing debate throughout the years. There are already some devices that monitor the changing of the climate, CanSat is a good example. The main goal of this project is to create a CanSat prototype and analyse the power used by it. The focus is on several factors such as the use of power with and without an upload program, the use of power when the sensors are switched on/off and the duration of the battery using the prototype. Some parts of the analysis have been done theoretically and practical. The project has been conducted with the aid of Arduino, an ammeter, and a voltmeter. The results show that the prototype would not spare much power if the sensors are switched off and on, this because not all the sensors have implemented the “sleep mode”. The difference between sleep mode and the normal functionality is equal to 0.026𝑊. Moreover, the difference in power when there is an upload program and when there is not an upload program is equal to 0.057𝑊. The duration of battery in the prototype is equal to 1 hour and 45 minutes according to the theoretical part, while the practical part showed a duration of 1 hour and 11 minutes. Moreover, the results show also that the prototype send the wrong values for some of the sensors when the battery have a low value. It was estimated a value of 7V of battery left to guarantee credible measurements. From the result it is possible to deduce that the decrease of power used from the CanSat prototype can be improved by finding sensors that have implemented the sleep mode, by having a small code and by having an electric platform that consume less power than Arduino. Keywords: CanSat, Power consumption, Battery life, Arduino.
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2

Elsmore, Chris. "Neighbourhood Watch : social resource monitoring." Thesis, Swansea University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678659.

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3

Szalbot, Michal. "Wattmetr s podporou komunikace PLC." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220633.

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Our thesis is about development of equipment, which combine two technology. First technology is wattmeter which is used to energy measurement and second is Power line communication. Wattmeter needs two variables for measurement, voltage and current. Voltage measurement is less difficult than measurement of current. Voltage can be reduce and measured by A/D converter. Current has to be transform to voltage and than can be measured same way. To do that we use current transformer. Than we design program for the microcontroller, involvement and PCB. Wattmeter is connect to PLC modem which has been chosen. Fusing this two technology we create wattmeter network. Next step was program which is used to network control and data collecting. This data are used to create charts in web application.
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4

Mangisa, Siphumlile. "Statistical analysis of electricity demand profiles." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1011548.

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An electricity demand profile is a graph showing the amount of electricity used by customers over a unit of time. It shows the variation in electricity demand versus time. In the demand profiles, the shape of the graph is of utmost importance. The variations in demand profiles are caused by many factors, such as economic and en- vironmental factors. These variations may also be due to changes in the electricity use behaviours of electricity users. This study seeks to model daily profiles of energy demand in South Africa with a model which is a composition of two de Moivre type models. The model has seven parameters, each with a natural interpretation (one parameter representing minimum demand in a day, two parameters representing the time of morning and afternoon peaks, two parameters representing the shape of each peak, and two parameters representing the total energy per peak). With the help of this model, we trace change in the demand profile over a number of years. The proposed model will be helpful for short to long term electricity demand forecasting.
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Chen, Chuen-Song. "On-chip current and power measurement techniques for integrated circuits with regulated power /." View online ; access limited to URI, 2008. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3314451.

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6

Lai, Chiu-cheong. "Electricity use and its conservation potential in the commercial sector : a case study in Hong Kong /." [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13498423.

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7

Huss, William Reed. "Load forecasting for electric utilities /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487263399023837.

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8

Si, Yau-li. "Forecasts of electricity demand and their implication for energy developments in Hong Kong." [Hong Kong : University of Hong Kong], 1990. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13009102.

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9

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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10

Chawdhry, P. K. "Identification of boiler-turbine systems in electric power stations." Thesis, Queen's University Belfast, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372987.

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Chiu, Yuk Ha. "A cross-country empirical study on electricity demand /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?ECON%202004%20CHIU.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.
Includes bibliographical references (leaves 33-35). Also available in electronic version. Access restricted to campus users.
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12

Gopalakrishnan, Chandra. "Effectiveness of electrical demand reduction strategies." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3776.

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Thesis (M.S.)--West Virginia University, 2004.
Title from document title page. Document formatted into pages; contains viii, 75 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 74-75).
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13

Yakum, Charles Nchonko. "Electric current measurement in power systems using optical fibre techniques." Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387450.

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14

Shao, Bin. "China's Electric Power Industry Reform: An Empirical Investigation." Thesis, University of Canterbury. Economics and Finance, 2010. http://hdl.handle.net/10092/5177.

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Electric power has become the most widely used secondary energy. As a result, the electricity industry's development will, in turn, directly influence other industries, people's daily lives, and the whole economy. China is one of the most rapidly developing economies, making it one of the biggest consumer of electricity in the world. Thus, the development of electric industry in China is not only important for the development of China itself, but also the energy pattern all over the world. In this study, we focus on analysing the market-oriented reform in China's electricity industry after the adoption of reforming and opening policies in 1978. By following the time path, the detailed content of the reform, as it was applied and modified over time, is first introduced. Then, an empirical investigation is conducted on the major policies in the process of China's electric power industry reform. Through quantitative measurement, the contribution of each major policy is clearly defined, so that conclusions concerning the reform in the past and suggestions for its future direction can be reached and made. It is found that both successes and deficiencies occurred in the reform process, and that China's electric industry has made significant efforts to overcome obstacles as they have been identified. However, even though great progress has been made in China's electric power industry from 1978 to 2009, more efforts are still required to finally achieve market operation in the industry. It is expected that this study can positively contribute to the development of China's electric power industry, as well as to electric power industries in other countries.
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15

Modlin, Danny Robert. "Utilizing time series analysis to forecast long-term electrical consumption /." Electronic version (PDF), 2006. http://dl.uncw.edu/etd/2006/modlind/dannymodlin.pdf.

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16

Kunchum, Sandeep. "A network infrastructure for real-time monitoring of campus energy consumption." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Kunchum_09007dcc80490489.pdf.

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Thesis (M.S.)--University of Missouri--Rolla, 2007.
Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed March 26, 2008) Includes bibliographical references (p. 83-84).
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17

Gupta, Pavan, University of Western Sydney, College of Law and Business, and School of Management. "Residential sector deregulation in the electricity industry : analysis of electricity consumption patterns." THESIS_CLAB_MAN_Gupta_P.xml, 2004. http://handle.uws.edu.au:8081/1959.7/744.

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The research presented in this thesis aims to improve our knowledge regarding the impact of privatisation and deregulation of public service type infrastructure industries. In recent years, Australia's industry reform policies have critically relied on rapid deregulation of major utilities such as telecommunication, gas and electricity. Although several industries have been deregulated in the last two decades, our understanding regarding the impact of deregulation on residential electricity market is still developing. In order to accomplish the research, about 400 residential customers were surveyed and their electricity consumption patterns (ECP)were monitored by installing special electronic meters. The findings are discussed in detail. As an implication to policy and practice there is an urgent need for a nation-wide standard,reshaping the practices of the electricity marketing and establishing a time-dynamic ECP monitoring system. Another important implication concerns the well-founded theories in micro-economic literature. This research has established that the price of the commodities and services charged by public service type utility suppliers should not be left entirely to the market forces concerned with demand - supply equilibrium. There is an urgent need to understand the role of different socio-economic segments in contributing to the economic efficiencies of public service type assets. More efficient segments should be equitably rewarded for their contributions rather than penalised perhaps due to the lack of their bargaining power.
Doctor of Philosophy (PhD)
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18

Sarris, Emmanouil. "Naval ship propulsion and electric power systems selection for optimal fuel consumption." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68573.

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Thesis (Nav. E.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and, (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. [100]-102).
Although propulsion and electric power systems selection is an important part of naval ship design, respective decisions often have to be made without detailed ship knowledge (resistance, propulsors, etc.). Propulsion and electric power systems have always had to satisfy speed and ship-service power requirements. Nowadays, increasing fuel costs are moving such decisions towards more fuel-efficient solutions. Unlike commercial ships, naval ships operate in a variety of speeds and electric loads, making fuel consumption optimization challenging. This thesis develops a flexible decision support tool in Matlab® environment, which identifies the propulsion and ship-service power generation systems configuration that minimizes fuel consumption for any ship based on its operating profile. Mechanical-driven propulsion systems with or without propulsion derived ship-service power generation, separate ship-service systems and integrated power systems are analyzed. Modeling includes hull resistance using the Holtrop-Mennen method requiring only basic hull geometry information, propeller efficiencies using the Wageningen B series and transmission and prime movers fuel efficiencies. Propulsion and ship-service power generation systems configuration is optimized using the genetic algorithm. US Navy's Advanced Surface Ship Evaluation Tool (ASSET) model for the DDG-51 Flight I destroyer was used for modeling validation. Optimal fuel consumption results are compared against the existing configuration for the DDG-51 Flight I destroyer using a representative operating profile.
by Emmanouil Sarris.
S.M.in Engineering and Management
Nav.E.
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19

Mardikar, Yogesh Mukesh. "Establishing baseline electrical energy consumption in wood processing sawmills a model based on energy analysis and diagnostics /." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5412.

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Thesis (Ph. D.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains xvi, 222 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 203-207).
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20

Patel, Ashaben Mehul. "Current measurement in power electronic and motor drive applications - a comprehensive study." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Patel_09007dcc8042b818.pdf.

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Thesis (M.S.)--University of Missouri--Rolla, 2007.
Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 5, 2008) Includes bibliographical references (p. 96-109).
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21

Wehbe, Yasser. "Model Estimation of Electric Power Systems by Phasor Measurement Units Data." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4419.

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This dissertation tackles the online estimation of synchronous machines' power subsystems electromechanical models using the output based Phasor Measurements Units (PMUs) data while disregarding any inside data. The research develops state space models and estimates their parameters and states. The research tests the developed algorithms against models of a higher and of the same complexity as the estimated models. The dissertation explores two estimations approaches using the PMUs data: i)non-linear Kalman filters namely the Extended Kalman Filter (EKF) and then the Unscented Kalman Filter (UKF) and ii) Least Squares Estimation (LSE) with Finite Differences (FN) and then with System Identification. The EKF based research i) establishes a decoupling technique for the subsystem the rest of the power system ii) finds the maximum number of parameters to estimate for classical machine model and iii) estimates such parameters . The UKF based research i) estimates a set of electromechanical parameters and states for the flux decay model and ii) shows the advantage of using a dual estimation filter with colored noise to solve the difficulty of some simultaneous state and parameter estimation. The LSE with FN estimation i) evaluates numerically the state space differential equations and transform the problem to an overestimated linear system whose parameters can be estimated, ii) carries out sensitivity studies evaluating the impact of operating conditions and iii) addresses the requirements for implementation on real data taken from the electric grid of the United States. The System Identification method i) develops a linearized electromechanical model, ii) completes a parameters sub-set selection study using si8ngular values decomposition, iii) estimates the parameters of the proposed model and iv) validates its output versus the measured output.
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22

VISCONTI, IGOR FERREIRA. "MEASUREMENT-BASED LOAD MODELING FOR DYNAMIC SIMULATIONS ON ELECTRIC POWER SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2010. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=16417@1.

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CENTRO DE PESQUISA DE ENERGIA ELÉTRICA
Este trabalho descreve uma metodologia para modelagem de cargas elétricas, utilizando dados de tensão e corrente registrados durante distúrbios no sistema de potência. Estes modelos são utilizados na representação de subsistemas da rede elétrica em simulações computacionais que preveem o comportamento dinâmico do sistema de potência após perturbações em suas condições normais de operação.São apresentados resultados práticos da metodologia proposta, onde a carga é definida como um sistema cuja saída é a variação da potência consumida e a entrada é a variação da tensão, ambas medidas em barramentos de 69 kV da Companhia Hidroelétrica do São Francisco (CHESF), ponto de entrega de energia para concessionárias distribuidoras de energia do nordeste brasileiro. Estas distribuidoras são modeladas como cargas, supridas pelo sistema de transmissão da CHESF e todos os elementos consumidores de energia são agregados nestes modelos equivalentes, parametrizados para simular o maior número de contingências típicas medidas em cada um destes barramentos de carga.A técnica de estimação de parâmetros dos modelos de cargas é o Algoritmo Genético (AG) cujos resultados apresentaram precisão para a simulação de contingências de características bem distintas, caracterizando a abrangência alcançada no processo de identificação de sistemas.Ao final do trabalho são apresentadas curvas de desvios de potência ativa e reativa causadas por afundamentos de tensão, ambos registrados nos barramentos das subestações da CHESF. Estas curvas foram utilizadas para estimar os parâmetros dos modelos, obtidos individualmente para cada uma das subestações estudadas.
This work describes a measurement-based load modeling methodology, using voltage and current data registered during power system disturbances. These load models are used on computational simulations for predicting power system stability after disturbances of system operational points. Practical results are presented of the proposed methodology, defining load as a system whose output is power deviation from its operational state and input is voltage sags, both measured at 69 kV bus bars of São Francisco Hydroelectric Company (CHESF), points of common coupling (PCC) between CHESF and local distribution utilities. Therefore, distribution utilities are seen as loads supplied by CHESF’s transmission system. All devices consuming power from the PCC are aggregated into an equivalent model, parameterized to simulate most typical contingencies measured by these 69kV load bars. Optimization technique used for load model parameter estimation is Genetic Algorithm (GA), showing his flexibility on implementation and good coverage and accuracy in the final results. At the end, it will be presented a set of active and reactive power curves during and after voltages sags, measured on CHESF’s substations. These curves were used as estimation data to parameterize load models for each substation chosen.
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23

SCHOUCHANA, FELIPE SIQUEIRA. "OPTIMIZATION OF ELECTRIC POWER SWAP IN BRASIL USING THE OMEGA MEASUREMENT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2010. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=16911@1.

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que torna complexo o processo de formação do preço da energia, já que o mesmo depende do comportamento das afluências futuras, que é altamente incerto. Em função dessa incerteza, o preço pode apresentar comportamento volátil, se tornando um fator de alto risco para os agentes do setor elétrico. No entanto, é comum que comercializadoras utilizem o mercado a vista para alavancar seus ganhos, visto que podem negociar energia elétrica entre diferentes submercados lucrando com as diferenças de preços existentes entre eles. A gestão do risco inerente a essas operações geralmente é realizada pelas próprias empresas que utilizam modelos financeiros para otimização de portfólio de contratos levando em conta métricas de risco. Uma prática comum é o Swap de energia elétrica no mercado a vista que consiste na compra e venda de energia para liquidação em determinada data. Na prática a comercializadora fica vendida na ponta ativa e comprada na ponta passiva, em submercados diferentes. Quando da liquidação financeira a comercializadora irá receber ou pagar um valor em dinheiro dependendo dos preços de cada submercado. Nesse contexto, o presente estudo oferece um modelo de decisão ótima em Swaps de energia elétrica utilizando como balizador de desempenho a medida Ômega com restrição de valor em risco (VaR – Value at Risk) de forma a auxiliar comercializadores a maximizarem seus lucros minimizando riscos por meio de operações casadas. Os resultados mostraram que a medida Omega é uma excelente métrica de decisão ótima de Swaps de energia elétrica visto que consegue incorporar toda a curva estatística da distribuição dos resultados simulados para as operações. A medida Omega também leva em conta um nível de retorno ou valor meta chamado de limite (L) definido pelo gestor, o qual é a fronteira entre o que se considera como ganho e como perda. A decisão ótima de Swap com base na maximização da medida Omega para contratos de energia elétrica em um horizonte de 12 meses resultou no conjunto das seguintes operações: CSE-VNE+CSE-VN (Compra Sudeste e Vende Nordeste + Compra Sudeste e Vende Norte).
The Brazilian electric sector underwent a major restructuring that began at the end of the 1990s, which aimed to increase the efficiency of the agents and the market as a whole. This process created the Regulated Contracting Environment (ACR) where the generators sell their energy through government-organized auctions, and the Free Contracting Environment (ACL) which enables deals between producers and consumers whose demand exceeds 3MW, directly or via brokers. Purchases in the ACL may be at fixed or previously-set prices, or even at floating prices based on the Spot Price (PLD). The PLD may be volatile, becoming a high risk factor for the electric sector agents. Energy supply is divided into four sub-markets: North, South, Northeast and Southeast/Midwest, and each presents a distinct PLD due to restrictions on the transmission lines and other factors. However, it is common for agents to trade in electric power swaps, which means trading energy among different sub-markets and profiting from price differences. The management of risk inherent in such operations is usually performed by the companies themselves, which use financial models to optimize contract portfolios, taking into account risk metrics. Thus, the trader will book a profit or loss depending on the prices in each sub-market. Against this backdrop, this study offers a model of optimal decision in Electric Power Swaps (buying and selling the same amount of energy) using the Omega Measurement as a performance indicator, restricted by value at risk (VaR) to help brokers maximize their profit while minimizing risks.
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Ghassemian, Alireza. "Robust Statistical Methods for Measurement Calibration in Large Electric Power Systems." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/40527.

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The Objective of the Remote Measurements Calibration (RMC) method is to minimize systematic errors through an appropriate scaling procedure. A new method for RMC has been developed. This method solves the problems of observability, multiplicity of solutions, and ambiguity of reference points associated with the method proposed by Adibi et. al. [6-9]. The new algorithm uses the simulated annealing technique together with the matroid method to identify and minimize the number of RTUs (Remote Terminal Units) required to observe the system. After field calibration, these RTUs provide measurements that are used to estimate the whole state of the system. These estimates are then returned as a reference for remotely calibrating the remaining RTUs. The calibration coefficients are estimated by means of highly robust estimator, namely the Least Median of Squares (LMS) estimator. The calibration method is applicable to large systems by means of network tearing and dynamic programming. The number of field calibrations can be decreased further whenever multiple voltage measurements at the same buses are available. The procedure requires that the measurement biases are estimated from recorded metered values when buses, or lines, or transformers are disconnected. It also requires the application of a robust comparative voltage calibration method. To this end, a modified Friedman test has been developed and its robustness characteristics investigated.
Ph. D.
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25

Contreras, Sergio. "Regional electricity demand in the United States." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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26

Gupta, Pavan. "Residential sector deregulation in the electricity industry : analysis of electricity consumption patterns /." View thesis, 2004. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20050225.104416/index.html.

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Thesis (Ph.D.) -- University of Western Sydney, 2004.
"A thesis presented to the University of Western Sydney, in partial fulfilment of the requirements of the degree of Doctor of Philosophy" Bibliography : leaves 273-285.
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Huang, Liling. "Electromechanical Wave Propagation in Large Electric Power Systems." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/11054.

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In a large and dense power network, the transmission lines, the generators and the loads are considered to be continuous functions of space. The continuum technique provides a macro-scale analytical tool to gain an insight into the mechanisms by which the disturbances initiated by faults and other random events propagate in the continuum. This dissertation presents one-dimensional and two-dimensional discrete models to illustrate the propagation of electromechanical waves in a continuum system. The more realistic simulations of the non-uniform distribution of generators and boundary conditions are also studied. Numerical simulations, based on the swing equation, demonstrate electromechanical wave propagation with some interesting properties. The coefficients of reflection, reflection-free termination, and velocity of propagation are investigated from the numerical results. Discussions related to the effects of electromechanical wave propagation on protection systems are given. In addition, the simulation results are compared with field data collected by phasor measurement units, and show that the continuum technique provides a valuable tool in reproducing electromechanical transients on modern power systems. Discussions of new protection and control functions are included. A clear understanding of these and related phenomena will lead to innovative and effective countermeasures against unwanted trips by the protection systems, which can lead to system blackouts.
Ph. D.
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Zumr, Zdenek. "Last Mile Asset Monitoring: Low Cost Rapid Deployment Asset Monitoring." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1967.

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Installation and utilization of residential distribution transformers has not changed substantially over a long period of time. Utilities typically size their transformers based on a formula that takes into account broadly what types and how many dwellings will be connected. Most new residential dwellings feature 200 Amp service per household with an anticipated energy demand of under 20,000 kWh per year. Average electrical energy consumption varies from state to state but averages to 11,280 kWh per year. Energy demand is expected to fall into a typical residential load curve that shows increased demand early in the morning, then decreasing during the day and another peak early to late evening. Distribution transformers are sized at the limit of the combined evening peak with the assumption that the transformer has enough thermal mass to absorb short overloads that may occur when concurrent loading situations among multiple dwellings arise. The assumption that concurrent loading is of short duration and the transformer can cool off during the night time has been validated over the years and has become standard practice. This has worked well when dwelling loads follow an averaging scheme and low level of coincidence. With the arrival of electric vehicles (EV's) this assumption has to be reevaluated. The acquisition of an electric vehicle in a household can drive up energy demand by over 4000 kWh per year. Potentially problematic is the increased capacity of battery packs and the resulting proliferation of Level 2 chargers. The additional load of a single Level 2 charger concurring with the combined evening peak load will push even conservatively sized distribution transformers over their nameplate rating for a substantial amount of time. Additionally, unlike common household appliances of similar power requirements such as ovens or water heaters, a Level 2 battery charger will run at peak power consumption for several hours, and the current drawn by the EVs has very high levels of harmonic distortion. The excessive loading and harmonic profile can potentially result in damaging heat build-up resulting in asset degradation. In this thesis I present a device and method that monitors pole mounted distribution transformers for overheating, collect and wirelessly upload data and initiate commands to chargers to change output levels from Level 2 to Level 1 or shut down EV charging altogether until the transformer returns into safe operational range.
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Smith, Mark Alan. "Improved dynamic stability using FACTS devices with phasor measurement feedback." Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/42417.

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With an increasing number of regulatory and economic factors making the operation of power systems more challenging, utilities must take full advantage of technological advances which allow more flexibility for operation. One of these advances is the combination of power electronic controllers and compensation devices known as F1exible AC Transmission Systems (FACTS) technology. This thesis will examine the ability of FACTS technology to improve dynamic stability when controlled with data obtained from another recent advancement, phasor measurement units (PMUs). Based on an overview of the relative capabilities of presently available FACTS devices, a specific device will be chosen to be modeled in a dynamic stability study. Eigenvalue sensitivity analysis will be used to determine the optimal placement for this FACTS device in regards to stability for a test power system. Then a state space model will be developed for the FACTS compensated test system, and eigenvalue sensitivity and time-domain methods will be used to determine the optimal controller characteristics for the modeled FACTS device. Stability results will be verified using eigenvalue analysis and time simulation techniques.
Master of Science
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Lam, Hoi-yee. "Voltage-current trajectory a 2-dimensional approach to understand electrical load signatures /." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B3890861X.

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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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32

De, Villiers Wernich. "Prediction and measurement of power line carrier signal attenuation and fluctuation." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52410.

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Thesis (MScEng)--University of Stellenbosch, 2001,
ENGLISH ABSTRACT: A frequency domain Power Line Carrier (PLC) simulation program, with the ability to simulate signal attenuation including the coupling equipment, was developed. This simulation program was put to the test against the independent program of Professor L.M. Wedepohl and against practical field measurements. The predictions of the two programs were in precise agreement for a wide range of input parameters. Results from the field tests and predictions also showed close agreement. Further investigations, applying the simulation program, explained how ground conductors and soil resistivity influences PLC signal propagation. An experiment, which was developed to monitor PLC signal attenuation, was installed on the PLC system between Koeberg power station and Acacia substation, both near Cape Town. Data logged continuously over 28 days, indicated measurable and deterministic PLC signal attenuation variations with typical time constants of a few hours. Simulations of the PLC system indicated that the signal amplitude variations were influenced by changes in the height above the ground plane of the phase conductor. This significant finding creates the possibility to obtain real time knowledge of the sag of an Over Head Transmission Line (OHTL) by exploiting an operational PLC system. The knowledge about real time sag can be used in economical dynamic ampacity control systems. The practical and financial benefits to the electricity supply and distribution industry can be significant.
AFRIKAANSE OPSOMMING: 'n Frekwensie gebied "Power Line Carrier" (PLC) simulasie program wat die sein verswakking en die koppeling verliese kan naboots, is ontwikkel. Die program is getoets teen die onafhanklike program van Professor L.M. Wedepohl asook praktiese metings in die veld. Die vooruitskatings van beide programme is presies die selfde vir 'n wye reeks van parameters. Metings en nabootsings het ook noue ooreenstemming getoon. Verdere ondersoek, m. b. v. die program, is gedoen ten einde te verduidelik hoe grond-geleiers en grond weerstand die PLC sein se voortplanting beïnvloed. 'n Eksperiment om die PLC sein se verswakking mee te monitor is ontwerp. Die eksperiment was geïnstalleer in die PLC stelsel tussen Koeberg kernkragstasie en Acacia substasie, naby Kaapstad. Die eksperiment was vir 28 dae geaktiveer en die data wat die eksperiment opgelewer het toon meetbare PLC sein verswakking met tyd konstantes van 'n paar uur. Verdere nabootsings het gewys dat die veranderende verswakking in die PLC seinsterkte toegeskryf kan word aan die wisseling in hoogte van die fase geleiers bo die grondvlak. Hierdie bevinding is van besondere belang aangesien dit die moontlikheid oopmaak om die gemiddelde sak van kraglyne in reële tyd en onder bedryfs toestande te kan meet. Die informasie van die reële sak van kraglyne kan gebruik word in effektiewe stroomdrae-vermoë beheer stelsels. Die praktiese en finansiële voordele wat krag voorsieners en verspreiders hieruit kan put kan aansienlik wees.
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33

Tong, Sai-kit. "A computer-aided measurement system for monopolar high-voltage direct-current coronating lines /." [Hong Kong] : University of Hong Kong, 1986. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12321771.

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34

Nguyen, Duy Huu Manh. "Analysing electricity markets with evolutionary computation." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2002. http://theses.library.uwa.edu.au/adt-WU2003.0018.

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The use of electricity in 21st century living has been firmly established throughout most of the world, correspondingly the infrastructure for production and delivery of electricity to consumers has matured and stabilised. However, due to recent technical and environmental–political developments, the electricity infrastructure worldwide is undergoing major restructuring. The forces driving this reorganisation are a complex interplay of technical, environmental, economic and political factors. The general trend of the reorganisation is a dis–aggregation of the previously integrated functions of generation, transmission and distribution, together with the establishment of competitive markets, primarily in generation, to replace previous regulated monopolistic utilities. To ensure reliable and cost effective electricity supply to consumers it is necessary to have an accurate picture of the expected generation in terms of the spatial and temporal distribution of prices and volumes. Previously this information was obtained by the regulated utility using technical studies such as centrally planned unit–commitment and economic–dispatch. However, in the new deregulated market environment such studies have diminished applicability and limited accuracy since generation assets are generally autonomous and subject to market forces. With generation outcomes governed by market mechanisms, to have an accurate picture of expected generation in the new electricity supply industry, it is necessary to complement traditional studies with new studies of market equilibrium and stability. Models and solution methods have been developed and refined for many markets, however they cannot be directly applied to the generation market due to the unique nature of electricity, having high inelastic demand, low storage capability and distinct transportation requirements. Intensive effort is underway to formulate solutions and models that specifically reflect the unique characteristics of the generation market. Various models have been proposed including game theory, stochastic and agent–based systems. Similarly there is a diverse range of solution methods including, Monte–Carlo simulations, linear–complimentary and quadratic programming. These approaches have varying degrees of generality, robustness and accuracy, some being better in certain aspects but weaker in others. This thesis formulates a new general model for the generation market based on the Cournot game, it makes no conjectures about producers’ behaviour and assumes that all electricity produced is immediately consumed. The new formulation characterises producers purely by their cost curves, which is only required to be piece–wise differentiable, and allows consumers’ characteristics to remain unspecified. The formulation can determine dynamic equilibrium and multiple equilibria of markets with single and multiple consumers and producers. Additionally stability concepts for the new market equilibrium is also developed to provide discrimination for dynamic equilibrium and to enable the structural stability of the market to be assessed. Solutions of the new formulation are evaluated by the use of evolutionary computation, which is a guided stochastic search paradigm that mimics the operation of biological evolution to iteratively produce a population of solutions. Evolutionary computation is employed as it is adept at finding multiple solutions for underconstrained systems, such as that of the new market formulation. Various enhancements to significantly improve the performance of the algorithms and simplify its application are developed. The concept of convergence potential of a population is introduced together with a system for the controlled extraction of such potential to accelerate the algorithm’s convergence and improve its accuracy and robustness. A new constraint handling technique for linear constraints that preserves the solution’s diversity is also presented together with a coevolutionary solution method for the multiple consumers and producers market. To illustrate the new electricity market formulation and its evolutionary computation solution methods, the equilibrium and stability of a test market with one consumer and thirteen thermal generators with valve point losses is examined. The case of a multiple consumer market is not simulated, though the formulation and solution methods for this case is included. The market solutions obtained not only confirms previous findings thus validating the new approach, but also includes new results yet to be verified by future studies. Techniques for market designers, regulators and other system planners in utilising the new market solutions are also given. In summary, the market formulation and solution method developed shows great promise in determining expected generation in a deregulated environment.
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Nicholson, Emma Leah. "Essays on restructured electricity markets." Connect to Electronic Thesis (ProQuest) Connect to Electronic Thesis (CONTENTdm), 2008. http://worldcat.org/oclc/436443232/viewonline.

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Mthunzi, Everett Mondliwethu. "Performance analysis of a protection scheme based on P-class synchrophasor measurements." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2378.

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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2016.
Power grid and system protection advancement greatly depend on technological advances. Advent technologies like digital microprocessor type protective relays facilitate paradigm shifts, providing inimitable beneficial engineering adaptations. Phasor measuring technology provides one such technological advance. The onset and rapid development of the Phasor Measuring Unit (PMU) provides an excellent platform for phasor-based, power system engineering. Power transmission constitutes a critical section in the electric power system. The power system transmission lines are susceptible to faults which require instant isolation to establish and maintain consistent system stability. This research focuses on the study of transmission line protection based on P-Class synchrophasor measurements. The IEEE C37.238-2011 Precision Time Protocol (PTP) paradigm shift facilitates practical application of synchrophasors in protection schemes. Synchrophasor procession and accurate data alignment over wide areas support the hypothesis of a phasor-based transmission line differential protection. This research aims to directly implement P-Class synchrophasors in transmission line differential protection, employing synchrophasors to determine fault conditions and administer corresponding protective actions in wide area transmission lines. The research also aims to evaluate the operational characteristics of the synchrophasor-based transmission line differential protection scheme. The research deliverables include a laboratory scale Test-bench that implements the PMU-based transmission line differential protection scheme, and a differential protection utility software solution that follows guidelines specified by the C37.118-2011 standard for synchrophasors. The findings stand to evaluate performance of the PMU-based line differential protection scheme, verifying the protection model as an alternate, practical and feasible backup protection solution. The research deliverables include a synchrophasor-based current differential algorithm, software utility for implementing the PMU-based protection scheme and a Test-bench for concept and feasibility validation.
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Urban, Rodney Gordon. "Power line corona noise prediction from small cage measurement." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50063.

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Thesis (PhD) -- Stellenbosch University, 2004.
Some digitised pages may appear illegible due to the condition of the original hard copy.
ENGLISH ABSTRACT: The radio noise (RN) performance of an AC high voltage transmission line is a determining factor when accessing the reliability of the design. The conducted RN level across the terminals of a PLC receiver, used in the teleprotection system of the line, is of particular concern. In this dissertation, existing empirical and semi-analytical RN prediction methods are evaluated by comparing the conducted RN levels of four South African lines to the predicted levels. Existing RN measurement protocols are consolidated and a new RN measurement protocol is proposed for the comparison. A prediction methodology, based on the EdF, EPRI and IREQ semi-analytical methods, is formulated. The semi-analytical methods are not able to accurately predict the variation of the conducted RN with frequency in the PLC band, nor are they able to predict the RN performance of short lines. A wideband excitation function, which considers the statistical characteristics of the measured RN pulse train, is therefore proposed in this dissertation. Having investigated the extraction of this excitation function from ESKOM’s Megawatt Park corona cage, it is concluded that a small corona cage is required. The design of a small cage is presented and the extraction of the excitation function is described. Attention is given to assessing the effect of changes in space charge distributions. The effect of space charge collision with an insulated cage on the extracted pulse parameters is linear, provided space charge diffusion is negligible. The onset streamer, positive streamer and negative streamer corona modes were identified as the only modes with measurable RN in the frequency regime 150 kHz to 30 MHz. Formulas are derived for the prediction of the inception gradients for these modes. The RN performance of an ACSR Hare conductor is extracted from the small cage. The RN performance of the Acacia-Koeberg line is also approximated in the PLC band. The dissertation concludes that the proposed wideband excitation function method is capable of accurately predicting the variation of RN levels with frequency. It can also be used to predict the RN performance of short line sections, as well as the relationship between RMS, QP and average RN levels from a transmission line.
AFRIKAANSE OPSOMMING: Die korona-werkverrigting van ‘n WS hoogspanningstransmissielyn het belangrike gevolge vir die betroubaarheid van die ontwerp van die lyn. Die geleide radioruis (RR) vlak op die kraglyndragolf kommunikasie sisteem, wat vir tele-beveiliging gebruik word, is veral van belang. In hierdie werkstuk word bestaande metodes gebruik om die korona-werkverrigting te bepaal en dan met gemete waardes van vier Suid Afrikaanse lyne te vergelyk. Bestaande RR meetmetodes word saamgevat en ‘n nuwe metingsprotokol word voorgestel om resultate te vergelyk. Na aanleiding van hierdie vergelykings word ‘n tegniek ontwikkel om die RR van ‘n lyn te voorspel. Hierdie tegniek gebruik die EdF, EPRI en IREQ metodes. Die voorgestelde tegniek kan nie die verandering van die RR met frekwensie bepaal nie. Dit kan ook nie die RR van kort lyne bepaal nie. ‘n Wyeband RR bron word dus voorgestel. Nadat ESKOM se Megawatt Park korona-kou ondersoek is, is die gevolgtrekking gemaak dat ‘n klein koronakou die nodige wyeband RR bron sal voorsien. Ruimtelading bots met die klein korona-kou. Die effek van hierdie botsings op die pulsparameters is lineer indien ladingsdiffusie nie plaasvind nie. Die aanvangs, positiewe en negatiewe kanaalontladings (“streamers”) is identifiseer as die enigste koronamodusse wat RR veroorsaak tussen 150 kHz en 30 MHz. Die spanning waarby hierdie modusse voorkom, is bepaal. Die korona-werkverrigting van ‘n “ACSR Hare” geleier is bepaal. Die korona-werkverrigting van die Acacia-Koeberg transmissie lyn is ook gekwantifiseer by die kraglyn-dragolf kommunikasie frekwensies. Die wyebandbron metode kan die verandering in RR met frekwensie goed voorspel. Die nuwe metode kan ook gebruik word om die RR van kort lyne te bepaal, asook die verband tussen RMS, QP en gemiddelde RR vlakke.
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Lam, Hoi-yee, and 林凱儀. "Voltage-current trajectory: a 2-dimensional approach to understand electrical load signatures." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3890861X.

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39

Del, Barga Christopher. "Design and Optimization of a Mobile Hybrid Electric System to Reduce Fuel Consumption." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/76797.

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The high costs and high risks of transporting fuel to combat zones make fuel conservation a dire need for the US military. A towable hybrid electric system can help relieve these issues by replacing less fuel efficient standalone diesel generators to deliver power to company encampments. Currently, standalone generators are sized to meet peak demand, even though peak demand only occurs during short intervals each day. The average daily demand is much less, meaning generators will be running inefficiently most of the day. In this thesis, a simulation is created to help determine an optimal system design given a load profile, size and weight constraints, and relocation schedule. This simulation is validated using test data from an existing system. After validation, many hybrid energy components are considered for use in the simulation. The combination of components that yields the lowest fuel consumption is used for the optimal design of the system. After determining the optimal design, a few design parameters are varied to analyze their effect on fuel consumption. The model presented in this thesis agrees with the test data to 7% of the measured fuel consumption. Sixteen system configurations are run through the simulation and their results are compared. The most fuel efficient system is the system that uses a 3.8kW diesel engine generator with a 307.2V, maximum capacity LiFeMgPO? battery pack. This system is estimated to consume 21% less fuel than a stand-alone generator, and up to 28% less when solar power is available.
Master of Science
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40

Doorduin, Riaan. "Electricity theft detection on a low voltage reticulation environment." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16310.

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Thesis (MScIng)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: Electricity theft in South Africa has become a major problem. This led to several developments from both industries and research institutes to counter these actions. Since equipment is already installed and major capital has been invested to provide electricity for a broad spectrum of consumers, the challenge is to find a low cost solution harnessing current investments and technology to detect electricity theft more accurately. This thesis investigates into the electricity theft topic. Two different methods, Time Domain Pulse Reflectometry and a data driven platform based on the Theory of Constraints philosophy, were investigated to provide means to detect and determine the impact of illegal electricity usage. Both methods required detailed designs to conduct preliminary proof of concept tests in a laboratory environment. These methods are evaluated against their economical viability, possible practical implications and applications. This thesis presents a practical approach to electricity theft detection and provides the basic tools for management of this ever-increasing problem.
AFRIKAANSE OPSOMMING: Suid Afrika se elektrisiteit diefstal statistiek het die afgelope jare skrikwekkend gegroei. Dit het die industrie genoop om baie meer navorsing in die area te doen. Met reeds gevestigde toerusting en tegnologie om di´e energie medium so effektief moontlik te versprei, is die uitdaging juis om ’n ekonomiese oplossing te vind om reeds beskikbare tegnologie¨e meer doeltreffend aan te wend. Die doel van die tesis is om die gebied van elektrisiteit diefstal na te vors. Twee verskillende metodes is ondersoek, naamlik Tydgebied-pulse-reflektometrie en ’n informasie gebaseerde stelsel wat op die Randvoorwaarde Teorie gebaseer is, om effektief die omvang van elektrisiteit diefstal in ’n mikro, asook makro omgewing te bepaal. Die twee metodes is in ’n beheerde omgewing getoets sodat die konsepte wat ontwikkel is bewys kon word. Die metodes is ge-evalueer in terme van die ekonomiese lewensvatbaarheid daarvan met inagneming van die praktiese implikasies. Die tesis bied bestuur die nodige kennis om elektrisiteit diefstal in die praktyk doeltreffend die hok mee te slaan.
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湯世傑 and Sai-kit Tong. "A computer-aided measurement system for monopolar high-voltage direct-current coronating lines." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1986. http://hub.hku.hk/bib/B31207467.

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42

Hamill, Andrew Ian. "Measurement and analysis of the standby power of twenty-seven portable electric spas." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/852.

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Portable electric spas are typically the largest electrical load in homes that have one. In recent years, the California Energy Commission’s California code of regulations, Title 20 has been revised to regulate the maximum allowable standby power for a portable electric spa based on the spa volume. The goal of this regulation is to require improvements to the lowest performing models, for which simple and cost effective improvements are readily available, without eliminating average or better performing products. In this research, the standby power of twenty seven portable electric spas was measured and compared to the Title 20 requirement. These tests resulted in nine of the twenty seven spas not meeting the allowable standby power. Analysis demonstrates that simple and inexpensive improvements to these nine spas would likely cause the spas to pass the Title 20 requirement. Additionally, temperature normalization developed in this research have been adopted by the California Energy Commission and included in revisions to Title 20.
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Matandirotya, Electdom. "Measurement and modelling of geomagnetically induced currents (GIC) in power lines." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2459.

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Thesis (DTech (Electrical Engineering))--Cape Peninsula University of Technology, 2016.
Geomagnetically induced currents (GIC) are currents induced in ground-based conductor networks in the Earth's surface. The GIC are driven by an electric eld induced by geomagnetic variations which are a result of time-varying magnetospheric-ionospheric currents during adverse space weather events. Several studies have shown that there is a likelihood of technological damage (the power grid) in the mid- and low-latitude regions that could be linked to GIC during some geomagnetic storms over the past solar cycles. The effects of GIC in the power system can range from temporary damage (e.g. protective relay tripping) to permanent damage (thermal transformer damage). Measurements of GIC in most substations are done on the neutral-to-ground connections of transformers using Hall-effect transducers. However, there is a need to understand the characteristics of GIC in the power lines connected to these transformers. Direct measurements of GIC in the power lines are not feasible due to the low frequencies of these currents which make current measurements using current transformers (CT) impractical. This thesis discusses two techniques that can be employed to enhance understanding GIC characteristics in mid-latitude regions. The techniques involve the measurement of GIC in a power line using differential magnetometer measurements and modelling GIC using the finite element method. Low frequency magnetometers are used to measure magnetic felds in the vicinity of the power lines and the GIC is inferred using the Biot-Savart law. A finite element model, using COMSOL-Multiphysics, is used to calculate GIC with the measured magnetic field and a realistic Earth conductivity profile as inputs. The finite element model is used for the computation of electric field associated with GIC modelling.
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Lintern, Matthew A. "The energy consumption mechanisms of a power-split hybrid electric vehicle in real-world driving." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/17959.

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With increasing costs of fossil fuels and intensified environmental awareness, low carbon vehicles, including hybrid electric vehicles (HEVs), are becoming more popular for car buyers due to their lower running costs. HEVs are sensitive to the driving conditions under which they are used however, and real-world driving can be very different to the legislative test cycles. On the road there are higher speeds, faster accelerations and more changes in speed, plus additional factors that are not taken into account in laboratory tests, all leading to poorer fuel economy. Future trends in the automotive industry are predicted to include a large focus on increased hybridisation of passenger cars in the coming years, so this is an important current research area. The aims of this project were to determine the energy consumption of a HEV in real-world driving, and investigate the differences in this compared to other standard drive cycles, and also compared to testing in laboratory conditions. A second generation Toyota Prius equipped with a GPS (Global Positioning System) data logging system collected driving data while in use by Loughborough University Security over a period of 9 months. The journey data was used for the development of a drive cycle, the Loughborough University Urban Drive Cycle 2 (LUUDC2), representing urban driving around the university campus and local town roads. It will also have a likeness to other similar driving routines. Vehicle testing was carried out on a chassis dynamometer on the real-world LUUDC2 and other existing drive cycles for comparison, including ECE-15, UDDS (Urban Dynamometer Driving Schedule) and Artemis Urban. Comparisons were made between real-world driving test results and chassis dynamometer real-world cycle test results. Comparison was also made with a pure electric vehicle (EV) that was tested in a similar way. To verify the test results and investigate the energy consumption inside the system, a Prius model in Autonomie vehicle simulation software was used. There were two main areas of results outcomes; the first of which was higher fuel consumption on the LUUDC2 compared to other cycles due to cycle effects, with the former having greater accelerations and a more transient speed profile. In a drive cycle acceleration effect study, for the cycle with 80% higher average acceleration than the other the difference in fuel consumption was about 32%, of which around half of this was discovered to be as a result of an increased average acceleration and deceleration rate. Compared to the standard ECE-15 urban drive cycle, fuel consumption was 20% higher on the LUUDC2. The second main area of outcomes is the factors that give greater energy consumption in real-world driving compared to in a laboratory and in simulations being determined and quantified. There was found to be a significant difference in fuel consumption for the HEV of over a third between on-road real-world driving and chassis dynamometer testing on the developed real-world cycle. Contributors to the difference were identified and explored further to quantify their impact. Firstly, validation of the drive cycle accuracy by statistical comparison to the original dataset using acceleration magnitude distributions highlighted that the cycle could be better matched. Chassis dynamometer testing of a new refined cycle showed that this had a significant impact, contributing approximately 16% of the difference to the real-world driving, bringing this gap down to 21%. This showed how important accurate cycle production from the data set is to give a representative and meaningful output. Road gradient was investigated as a possible contributor to the difference. The Prius was driven on repeated circuits of the campus to produce a simplified real-world driving cycle that could be directly linked with the corresponding gradients, which were obtained by surveying the land. This cycle was run on the chassis dynamometer and Autonomie was also used to simulate driving this cycle with and without its gradients. This study showed that gradient had a negligible contribution to fuel consumption of the HEV in the case of a circular route where returning to the start point. A main factor in the difference to real-world driving was found to be the use of climate control auxiliaries with associated ambient temperature. Investigation found this element is estimated to contribute over 15% to the difference in real-world fuel consumption, by running the heater in low temperatures and the air conditioning in high temperatures. This leaves a 6% remainder made up of a collection of other small real-world factors. Equivalent tests carried out in simulations to those carried out on the chassis dynamometer gave 20% lower fuel consumption. This is accounted for by degradation of the test vehicle at approximately 7%, and the other part by inaccuracy of the simulation model. Laboratory testing of the high voltage battery pack found it constituted around 2% of the vehicle degradation factor, plus an additional 5% due to imbalance of the battery cell voltages, on top of the 7% stated above. From this investigation it can be concluded that the driving cycle and environment have a substantial impact of the energy use of a HEV. Therefore they could be better designed by incorporating real-world driving into the development process, for example by basing control strategies on real-world drive cycles. Vehicles would also benefit from being developed for use in a particular application to improve their fuel consumption. Alternatively, factors for each of the contributing elements of real-world driving could be included in published fuel economy figures to give prospective users more representative values.
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Davalbhakta, Aneesh. "Improved configurations of sensors for the measurement of tower footing resistance a thesis presented to the faculty of the Graduate School, Tennessee Technological University /." Click to access online, 2008. http://proquest.umi.com/pqdweb?index=0&did=1597632921&SrchMode=1&sid=4&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1279309880&clientId=28564.

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46

Beute, Nico. "Domestic utilisation of electrical grid energy in South Africa." Thesis, Potchefstroom University, 1993. http://hdl.handle.net/20.500.11838/2187.

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Thesis (PhD (Electrical Engineering))--Potchefstroom University, 1993.
The domestic sector is one of the largest users of nett energy in the RSA (24%, excluding energy used for transport), but it accounts for only 14% of the electrical energy used in the RSA. There is a very strong correlation between the time of the peak of the load for the domestic sector and the time of the peak of the national load. The domestic load is the largest contributor to the peak of the national load. This makes the domestic load more important than is generally realised. Only limited research has been done about the ways in which domestic energy is used in South Africa. Developed countries, such as the United States of America, are continuously engaged in end-use load research, so they have vast data banks available on domestic end-uses of electricity. Data on domestic end-use of electricity are urgently needed especially for South Africa with its very fast growing newly urbanised sector. Since most energy sources are not replenishable, ways and means must be found to promote the wise and effective use of all forms of energy. Effective use of energy can only be promoted if the ways in which electricity is used are known. In this dissertation the electrical energy requirements of the South African domestic sector are analyzed for the present situation and for the next few decades. A model is developed to represent the electrical load. The model has subsections representing the components of the national domestic electrical load, concentrating on electrical energy for domestic water heating, with responses to factors such as: * population growth, * urbanisation, * electrification, * energy efficiency of appliances, * consumer awareness of energy conservation. The model is to be used for scenario planning of the electrical grid. The results of this study will assist to ensure effective planning of the electrical grid of South Africa into the next century.
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Baldwin, Thomas L. "Real-time phasor measurements for improved monitoring and control of power system stability." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-170758/.

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48

Chau, Man Kit. "A practical proposal for the regulation of the post-2008 Hong Kong electricity industry based on foreign experiences of market reform in recent years." HKBU Institutional Repository, 2006. http://repository.hkbu.edu.hk/etd_ra/673.

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49

Frozza, Janquiel Fernando. "Eficiência energética em indústria frigorífica: desafios de implantação." Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/762.

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Esta pesquisa tem por objetivo efetuar uma investigação acerca da eficiência energética nas indústrias, com foco na identificação dos potenciais de conservação de energia e possíveis barreiras para se implantar um sistema de gestão de energia, tendo como principais motivações o lançamento do Plano Nacional de Eficiência Energética (PNEf), que prevê uma grande economia de energia para os próximos anos, e da norma ABNT NBR ISO 50001- Sistema de gestão de energia. Num primeiro instante, fez-se um estudo dos principais métodos de gestão e eficiência energética que estão sendo empregados nas indústrias. Após o desenvolvimento de estudos preliminares, realizou-se uma auditoria energética em um frigorífico de abate de aves situado na região Sudoeste do Paraná. Nesta auditoria foram estabelecidos os centros de maior consumo, as linhas de base dos principais insumos energéticos e potenciais de conservação de energia dos principais módulos temáticos. Verificou-se que o sistema de refrigeração representa aproximadamente 81% do consumo de energia elétrica da planta e que do total de 11 módulos temáticos existentes, três deles representam aproximadamente 97% do consumo de energia elétrica da planta, sendo motores, sistema de refrigeração e sistema de ar comprimido. Constatou-se também, com uma análise econômica de perdas, que há potenciais de conservação de energia, principalmente em motores. Por fim, identificaram-se as principais barreiras para se implantar um sistema de gestão de energia em uma planta, principalmente no que se refere à elaboração de linhas de base e indicadores de desempenho energético. Tais barreiras demonstram uma falsa expectativa do PNEf para alcançar as atuais metas se não houver maior impacto dos progressos induzidos (por políticas públicas).
This research has an objective to investigate the electrical power efficiency in industries, aiming to identify potential energy saving and possible barriers to deploy an energy management system, having as one of its priorities the main motivations to the release of a National Plan of Electrical Efficiency (NPEE), in which forecast a great power saving for the following years and the norm ABNT NBR ISO 50001-Energy management system. At a first moment, a study was made about the main methods of electrical efficiency management, in which are being introduced in industries. After the development of preliminary studies, an electrical audit was carried out in a poultry slaughter cooler on the southwest region of Paraná. On the audit were established the centers of greater consumption and the baselines of the main energetic imputs and potential ways of electrical energy saving from the main thematic modules.It has been verified that the cooling system represents approximately 81% of electrical energy consumption of the plant and of the total of eleven modules; three of them represent approximately 97% of the power consumption of the entire plant, as engines, cooling system and compressed air system. It has been also found out, with an economic analysis of losses, there are potentials means of power saving, especially when it comes to engines. At last, was identified the main barriers to deploy an energy management system in a plant, mainly as regards the elaboration of baselines and indicators of electrical performance. These barriers have shown a fake expectation of the NPEE to reach the present goals if there's no impact on the progresses prompted (by public politics.)
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Si, Yau-li, and 史有理. "Forecasts of electricity demand and their implication for energy developments in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31976384.

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