Дисертації з теми "ELECTRICAL UTILITY"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: ELECTRICAL UTILITY.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "ELECTRICAL UTILITY".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
McGeachie, Michael J. "Utility functions for ceteris paribus preferences." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/16842.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.Includes bibliographical references (p. 101-103).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Ceteris paribus preference statements concisely represent preferences over outcomes or goals in a way natural to human thinking. Many decision making methods require an efficient method for comparing the desirability of two arbitrary goals. We address this need by presenting an algorithm for converting a set of qualitative ceteris paribus preferences into a quantitative utility function. Our algorithm is complete for a finite universe of binary features. Constructing the utility function can, in the worst case, take time exponential in the number of features. Common forms of independence conditions reduce the computational burden. We present heuristics using utility independence and constraint based search to achieve efficient utility functions.
by Michael McGeachie.
S.M.
2
Xie, Kaicheng. "Automatic Utility Meter Reading." Cleveland State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=csu1270587412.
Повний текст джерела
3
Steward, Duane A. (Duane Allen) 1954. "Utility assessment based on individualized patient perspectives." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50506.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Includes bibliographical references (p. 203-211).
The feasibility of using the terminology of the individual patient to capture and express the individual's particular, perhaps unique, value system for healthiness is explored as a means to evaluate the quality of life. The hypothesis is that a systematic approach that treats the patient as a competent expert on a patient's perception of what it means to be healthy is a viable approach to his or her values. It is anticipated that eliciting such knowledge in a form that health care providers can use will enhance medical decision making. A systematic and rigorous protocol is described consisting of a reconstruction of utility assessment using traditional methodological building blocks applied to the descriptors elicited from the individual. The representation of values is multidimensional. Ordered nominal scales are constructed from the words of the individual's description of familiar people in a structured interview. A complete list of comprehensive scales is composed as indicated by the responses of the individual to hypothetical decisions involving tradeoffs. The result is a scoring system for health state descriptions suitable to represent values for the outcomes in medical decision models constructed by the medical community. The output is a patient preference model referred to as an Individualized Multidimensional Quality of Life (IMQOL) model. This model also provides a means to describe and rank potential outcomes from the same individualized perspective. Feasibility is explored by empirical evaluation of sixteen interviews of dialysis patients with the IMQOL protocol and applying the resulting model to the patient's own health as well as four other states of health common in dialysis therapy. Comparison is made to results of quality of life assessment with standard gamble and time tradeoff methods in the same patients for the same described outcomes. Qualitative responses from patients regarding their confidence in the representation of their values are rewarding. Results are quantitatively comparable to traditional utility assessment. A prototypic computer program is used to substantiate the programmability and potential for automation. The protocol expands the information contributing to understanding by both the health care provider and the patient. Future evaluation and extension are discussed.
by Duane A. Steward.
Ph.D.
4
Allen, Eric H. (Eric Hickcox). "Stochastic unit commitment in a deregulated electric utility industry." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9951.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Also issued in leaves.
Includes bibliographical references (p. 237-239).
by Eric H. Allen.
Ph.D.
5
Hsieh, P. Angela (Pauting Angela). "Proposals for a restructured California state electric service utility industry." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36538.
Повний текст джерела
6
Thompson, Jeffrey Craig. "An expert system for protection system design of interconnected electrical distribution circuits." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-170345/.
Повний текст джерела
7
Aquilué, de Pedro Ricardo. "Power line communications for the electrical utility: physical layer design and channel modeling." Doctoral thesis, Universitat Ramon Llull, 2008. http://hdl.handle.net/10803/9138.
Повний текст джерелаАнотація:
El món de les comunicacions per la xarxa elèctrica (CXE) pot ser dividit en tres grans tipus: CXE en baix voltatge (CXE-BV), en mig voltatge (CXE-MV) i en alt voltatge (CXE-AV). En aquests últims anys, les CXE-BV han atret una gran expectació, ja que les seves capacitats han fet d'aquesta tecnologia una bona opció com alternativa pel bucle local d'accés i pel desplegament de xarxes d'àrea local, focalitzades aquestes últimes en l'entorn domèstic. A més, les CXE-BV inclouen un conjunt d'aplicacions de baixa velocitat orientades a l'operador, com la lectura automàtica de comptadors (LAC), distribució de càrrega, facturació dinàmica, etc. Per altra banda, les CXE-MV i CXE-AV, històricament lligades a tasques de telecontrol i teleprotecció, s'estan començant a considerar com un canal de comunicacions eficient i fiable. El desenvolupament de sistemes digitals i els esforços d'estandardització estan fent d'aquests canals un medi atractiu per a que els operadors elèctrics ofereixin serveis de comunicacions, ja que no necessiten invertir en infraestructura perquè la xarxa elèctrica ja està desplegada.En aquesta Tesi s'introduiran i es comentaran les particularitats de les tres xarxes elèctriques, després, es mostraran al lector les solucions tecnològiques existents pels canals de BV basats en la norma Europea CENELEC així com pels canals d'AV, mostrant que els sistemes actuals de LAC ofereixen una diversitat freqüencial molt baixa i que els mòdems CXE-AV estan ancorats en estendards antiquats.
Aquest treball es mou per les tres topologies de la xarxa, particularment, en aplicacions orientades a la banda CENELEC, en mesura i modelat de canal, i en mesura i disseny del nivell físic per sistemes CXE-BV, CXE-MV i CXE-AV respectivament. Els sistemes actuals que exploten la banda CENELEC ofereixen mecanismes d'explotació de la diversitat freqüencial del canal molt limitats o nuls, donant lloc a una baixa robustesa en front a interferències i soroll de fons acolorit. Aquest treball proposa un esquema de modulació multiportadora que, mantenint una complexitat baixa, ofereix unes altes prestacions permetent un bon nivell d'explotació de la selectivitat freqüencial. Per al que a CXE-MV respecta, aquesta Tesi desenvolupa un model de canal determinístic-estadístic pels anells urbans de distribució de potència i, finalment, en sistemes CXE-AV, aquest treball proposa, basat en mesures de canal i proves de camp, un nivell físic de banda ampla capaç de incrementar la velocitat de comunicació mentre manté una baixa densitat espectral de potència limitant així la interferència a altres sistemes.
PARAULES CLAU: Power line communications (PLC), low voltage (LV), medium voltage (MV), high voltage (HV), automatic meter reading (AMR), orthogonal frequency division multiplexing (OFDM), multicarrier spread spectrum (MC-SS), communication system design, channel measurements, channel modeling, scattering parameters.
El mundo de las comunicaciones por la red eléctrica (CRE) puede ser dividido en tres grandes tipos: CRE en bajo voltaje (CRE-BV), en medio voltaje (CRE-MV) y en alto voltaje (CRE-AV). En estos últimos años, las CRE-BV han atraído una gran expectación, ya que sus capacidades han hecho de esta tecnología una buena opción como alternativa para el bucle local de acceso y para el despliegue de redes de área local, focalizadas estas últimas en el entorno doméstico. Además, las CRE-BV incluyen un conjunto de aplicaciones de baja velocidad orientadas al operador como la lectura automática de contadores (LAC), distribución de carga, facturación dinámica, etc. Por otro lado, las CRE-MV y CRE-AV, históricamente ligadas a tareas de telecontrol y teleprotección, se están empezando a considerar como un canal de comunicaciones eficiente y fiable. El desarrollo de sistemas digitales y los esfuerzos de estandarización están haciendo de estos canales un medio atractivo para que los operadores eléctricos ofrezcan servicios de comunicaciones, ya que no necesitan invertir en infraestructura porque la red eléctrica ya está desplegada.
En esta Tesis se introducirán y se comentarán las particularidades de las tres redes eléctricas, luego, se mostrarán al lector las soluciones tecnológicas existentes para los canales de BV basados en la norma Europea CENELEC así como para los canales de AV, mostrando que los sistemas actuales de LAC ofrecen una diversidad frecuencial muy baja y que los módems CRE-AV están anclados en estándares anticuados.
Este trabajo se mueve por las tres topologías de red, particularmente, en aplicaciones orientadas a la banda CENELEC, en medida y modelado de canal, y en medida y diseño del nivel físico para sistemas CRE-BV, CRE-MV y CRE-AV respectivamente. Los sistemas actuales que explotan la banda CENELEC ofrecen mecanismos de explotación de la diversidad frecuencial del canal muy limitados o nulos, dando lugar a una escasa robustez frente a interferencias y ruido de fondo coloreado. Este trabajo propone un esquema de modulación multiportadora que, manteniendo una complejidad baja, ofrece unas altas prestaciones permitiendo un buen nivel de explotación de la selectividad frecuencial. Por lo que a CRE-MV respecta, esta Tesis desarrolla un modelo de canal determinístico-estadístico para los anillos urbanos de distribución de potencia y, finalmente, en sistemas de CRE-AV, este trabajo propone, basado en medidas de canal y pruebas de campo, un nivel físico de banda ancha capaz de incrementar la velocidad de comunicación mientras mantiene una baja densidad espectral de potencia limitando así la interferencia a otros sistemas.
PALABRAS CLAVE: Power line communications (PLC), low voltage (LV), medium voltage (MV), high voltage (HV), automatic meter reading (AMR), orthogonal frequency division multiplexing (OFDM), multicarrier spread spectrum (MC-SS), communication system design, channel measurements, channel modeling, scattering parameters.
The world of Power line communications (PLC) can be divided into three main types: low voltage PLC (LV-PLC), medium voltage PLC (MV-PLC) and high voltage PLC (HV-PLC). These last years, LV-PLC has attracted a great expectation since its wideband capabilities has made this technology a suitable choice for last-mile access and in-home communications. Moreover, LV-PLC also includes a utility oriented low frequency and low speed applications, such as automatic meter reading (AMR), load distribution, dynamic billing and so on. On the other hand, MV-PLC and HV-PLC, historically oriented to teleprotection and telecontrol tasks, are being considered as a reliable communication channel. The development of digital equipment and the standardization efforts are making those channels an attractive medium for electrical utilities telecommunications services, since the network, as well as in LV-PLC, is already deployed.
In this PhD dissertation, the three different PLC topologies are reviewed and the different communications techniques in such channels exposed. Then, a deep technological review of existing AMR solutions for the European CENELEC band, as well as HV-PLC systems is given, showing that existing AMR systems deliver low frequency diversity and HV-PLC systems are anchored in old fashioned standards.
This work walks around the three topologies, specifically, CENELEC band utility oriented applications, channel measurement and modeling and channel measurement and physical layer design, regarding LV-PLC, MV-PLC and HV-PLC respectively. Existing CENELEC compliant systems deliver low or none frequency diversity mechanisms, yielding in a low robustness against colored noise and interference. This work propose a multicarrier based physical layer approach that, while keeping the complexity low, delivers high performance allowing a great level of frequency diversity. Focusing on MV-PLC, a hybrid deterministic-statistical channel model for urban underground rings is developed and, finally, in HV-PLC systems, this work proposes, based on measurements and field tests, a wideband physical layer in order to increase data rate while keeping low both the power spectral density and possible interference to other systems.
KEYWORDS: Power line communications (PLC), low voltage (LV), medium voltage (MV), high voltage (HV), automatic meter reading (AMR), orthogonal frequency division multiplexing (OFDM), multicarrier spread spectrum (MC-SS), communication system design, channel measurements, channel modeling, scattering parameters.
8
Thapliya, Bikash. "Power utility restructuring and power-sector financing in developing countries." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42670.
Повний текст джерела
9
Neuman, Sabrina M. "Non-intrusive water utility monitoring and free-space load monitoring." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62750.
Повний текст джерелаАнотація:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 151).
This work presents a non-intrusive, single-point sensing scheme to monitor the water usage for various loads on a water utility pipe network through the vibration of a pipe near the water intake source. Experiments with the water utility sensor provided data sufficient to identify individual loads on the water distribution network both alone and during operation of multiple loads. This sensor setup is useful for smart-metering applications to promote water conservation by keeping track of the operational schedule of individual loads on the local water network. This work also presents the development of a free-space sensor to provide information about the operation and location of electrical loads: an electroquasistatic (EQS) sensor to detect voltage-mode events. The free-space sensor was able to detect events in a room, such as the activation of a line upon turning on a power strip or switching a light switch. This sensor could supplement a power monitoring system by helping to localize the activation of loads.
by Sabrina M. Neuman.
M.Eng.
10
Cardell, Judith Bernitt. "Renewable energy technologies : analysis and policy tools for utility integration." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/34046.
Повний текст джерелаАнотація:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994.Includes bibliographical references (p. 143-150).
by Judith Bernitt Cardell.
M.S.
11
Baris, A. N. Dalsu. "Suicide and other causes of death in electrical utility workers : their association with exposure to electric and magnetic fields." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28672.
Повний текст джерелаАнотація:
This dissertaion comprises three related papers.The first paper reports a historical cohort mortality study which was carried out among 21,744 electrical utility workers in the province of Quebec. A total of 1582 deaths were observed at the end of follow-up (1970-1988). A job exposure matrix (JEM) was used to estimate the exposure to 60 Hz electric, magnetic, and pulsed electromagnetic fields (PEMF) from the code of the last job held by each worker. The results showed no evidence of excess of cause specific or general mortality relative to provincial death rates in the cohort overall. The ratios of Standardized Mortality Ratios (SMRs) as estimates of rate ratio (RR) in the exposed relative to the background group were also calculated. Statistically significant RRs were found for pancreatic cancer for electric fields (RR = 2.8, 95% Confidence intervals (CI) 1.13-7.01) and for lung cancer for PEMF (RR = 1.56, 95% CI 1.05-2.25). Deaths caused by accidents and violence showed significant RRs for electric fields (RR = 2.16, 95% CI 1.59-2.92), magnetic fields (RR = 1.76, 95% 1.29-2.39) and for PEMF (RR = 1.96, 95% CI, 1.40-2.71). Occupational accidents related to power lines explain for some of the excess of deaths from accidents and violence. There was a small non-significant association with magnetic fields for leukaemia (RR = 1.52, 95% CI 0.45-4.47) and brain cancer (RR = 1.59, 95% CI 0.57-4.31), but the results for these two sites were based on small numbers.
The second paper reports a case-cohort study to investigate a previously suggested association between exposure to electric and magnetic fields and suicide. Forty-nine deaths from suicide between 1970 and 1988 were identified in the above-mentioned cohort and a sub-cohort comprising a one percent random sample was selected from it. Cumulative and current exposures to electric fields, magnetic fields and PEMF were estimated for the sub-cohort and cases through the JEM. For cumulative exposure, rate ratios (RR) for all three fields showed mostly small non-significant increases in the medium and high exposure groups. The most elevated risk was found in the medium exposure group for electric field-geometric mean (RR = 2.76, 95% CI 1.15-6.62). The results did not differ after adjusting for socioeconomic status (SES), alcohol use, marital status and mental disorders. There was little evidence for an association of risk with exposure immediately prior to the suicide. Small sample size (deaths from suicide) and inability to control for all potential confounding factors were the main limitations of this study.
The third paper reports a study of validity attributing magnetic field exposure by using a worker's last job. This was done by comparing, in a sample of the cohort, estimates obtained using last job with those obtained using full work histories. The correlation between indices based on last job and those based on all jobs varied between 0.75 and 0.78. The study showed that the last job was particularly good in identifying the highest exposed individual. The results are most likely to be generalizable to other industries in which highest exposed jobs are also skilled jobs.
12
Eppinger, Crystal. "Impact Analysis of Increased Dispatchable Resources on a Utility Feeder in OpenDSS." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/4000.
Повний текст джерелаАнотація:
Oregon utilities are replacing their portfolios of traditional fossil fuel generation with renewable generating sources. Stepping away from carbon-producing energy will leave a deficit of on-demand power, resulting in decreased reliability. To overcome these technical challenges, utilities must maximize the use of their present dispatchable resources. One such resource is the Portland General Electric (PGE) Dispatchable Standby Generation Program (DSG), which is an aggregated 105 MWs of distributed generation (DG). These resources are brought on-line when there is a critical need for power. Resources are added to the program if a transfer trip scheme is in place or a modeling study reveals that the feeder load is at least three times the generator capacity. If the load-to-capacity ratio were lower, more assets could be added to the DSG program.
To investigate the impacts of lowering the DG load-to-capacity ratio on existing distribution feeders, we use Open-Source Distribution System Simulator (OpenDSS). We modeled the Oxford Rural feeder by converting a utility CYME database to instantiation files using several MATLAB programs. A MATLAB control program varies the load-to-capacity ratio of the OpenDSS feeder model and monitors the generator behavior immediately following a fault. We analyzed the results to determine the ideal load-to-capacity ratio that prevents unintentional islanding. The results show that the instantaneous (50) relay element settings dictate both the minimum load-to-capacity ratio and the maximum DG capacity. The present three-to-one ratio is very conservative and can be reduced.
Additional dispatchable resources include a five MW battery-inverter system currently used as grid-back up. The battery is grid-tied to a 12.4 kV feeder making it an ideal candidate for conservation voltage reduction (CVR). Using the same feeder model, we investigated the effects of lowering the system voltage to the allowable minimum using injections of reactive power. A lower system voltage reduces the load at peak times. Conversely, increasing the voltage prevents generation conflicts. To determine the benefit of CVR by VAr-injection on the Oxford Rural feeder, we created a MATLAB optimization program to output the optimal feeder voltage for reduced system power. We use a Simulink feedback model to determine the appropriate reactive power needed to achieve the voltage change. We analyze the system model to reveal that the feeder is ideal for CVR but the system capacity must be increased to achieve the maximum power reduction.
13
Wang, Fan. "UTILITY-BASED RESOURCE ALLOCATION STRATEGIES AND PROTOCOL DESIGN FOR SPECTRUM-ADAPTIVE WIRELESS NETWORKS." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/195088.
Повний текст джерелаАнотація:
Resource allocation strategies, including power control, rate adaptation, and dynamic spectrum access, have been the keys to improving the performance of dynamic (mobile) wireless networks. In this dissertation, we propose several resource optimization schemes for various wireless network architectures, with the goal of maximizing the system throughput and/or minimizing the total energy consumption. These schemes are integrated into the design of distributed medium-access control (MAC) protocols. We propose a game theoretic power control scheme for single-channel ad-hoc networks, and design an efficient MAC protocol, called GMAC, that implements such a scheme in a distributed fashion. GMAC allows for multiple potential transmitters to contend for the channel through an admission phase that these transmitters to determine their appropriate transmission powers. Successful contenders proceed concurrently following the admission phase. We then study the operation of spectrum-agile (cognitive) radios in multi-channel, multi-hop wireless network setting. Two principal cases are considered: exclusive-occupancy and interference-based channel models. For the case of exclusive-occupancy channel models, we design a MAC protocol that exploits the "dual receive" capabilities of the radios to maximize the network throughput. We then propose a cross-layer framework for joint adaptive load/medium access controls. Under this framework, the traffic loads of individual node are adapted based on local MAC parameters. For the case of interference-based channel models, when system throughput is the primary performance metric, we apply "price-based" iterative water-filling (PIWF) algorithms for resource allocation. When energy consumption is the primary metric, we propose a selfish update algorithm and an incentive-based update algorithm for minimizing the power consumption while satisfying the rate and power mask requirements. These algorithms are implemented by having nodes repeatedly negotiate their best power/spectrum to reach a good Nash Equilibrium. An efficient multi-channel MAC protocol is proposed to facilitate the radio negotiation and convergence phase. Simulation results indicate that our proposed protocols achieve significant throughput/energy improvements over existing protocols.
14
Abu-Sara, Mohammad. "Digital control of utility and parallel connected three-phase PWM inverters." Thesis, University of Southampton, 2004. https://eprints.soton.ac.uk/47947/.
Повний текст джерелаАнотація:
This thesis is mainly concerned with fundamental investigations into digital current control of utility-connected PWM inverters with output LCL filter whose capacitors are connected to the dc link rails. The thesis also presents analysis and evaluations of alternative three-level PWM inverters and alternative filter configurations. Additionally, the thesis presents investigations into parallel-connected PWM inverters. Various pulse width modulated (PWM) controllers including hysteresis and linear controllers have been reviewed. Hysteresis controller combines the current control task with the voltage modulation task. This makes the hysteresis controller unable to dampen resonance when used with an LCL filter and also unable to reject utility disturbance. On the other hand, linear controllers separate the current control task from the voltage modulation task. This allows exploitation of the advantages of open loop modulators including carrier based PWM (CB-PWM) and space vector modulation (SVM) such as constant switching frequency and well-defined harmonic spectrum. A linear digital current controller with CB-PWM has been analysed and designed, aided by computer simulation using Matlab Simulink. The controller structure is based on two feedback loops of the output current and the filter capacitor current, which has been shown to provide extra degree of freedom, and enables better controller performance compared to controllers with a one-feedback-loop structure. Additionally, the controller incorporates a feedforward loop to compensate for utility voltage disturbance. The effect of the processor computational time delay on system stability has been investigated using the modified Z-transform. The investigations have shown that the optimum sampling rate should be twice the PWM carrier frequency, and the optimum sampling instant should be synchronized with the peaks of the PWM carrier in order to minimize the effect of the current switching frequency ripple disturbance. However, in practice due to computational time delay, it is not possible sample at the peaks of the PWM carrier, which may result in distortion in the output current due to sampling of the switching frequency ripple. Hence a novel nonlinear time delay compensator that accurately calculates the variation in the capacitor current during time has been proposed and demonstrated to be effective in rejecting the switching ripple disturbance. In addition, a novel digital sampling scheme in which the sampling is delayed by half a PWM carrier cycle been proposed. Using this scheme combined with a time delay state observer, better switching disturbance rejection was achieved. The proposed current controller has been experimentally implemented using a digital signal processor DSP and the results have shown that the quality of the output current complies with the standards on harmonic limits for electricity distribution systems. An alternative three-level inverter structure has also been studied in order to reduce switching frequency ripple and hence the inductor cost. Simulation results have shown that filter inductor ripple current of a three-level inverter is on average half that of a two-level inverter but at the cost of extra power switches. A comparative study between different filter structures has also been carried out. It has been shown that connecting the capacitors to the dc-link decouples the phase and removes neutral voltage fluctuations with respect to the dc link. On the other hand, connecting the filter capacitor in delta or star, halves the inductor ripple current. Wireless control of parallel-connected PWM inverters using frequency and voltage drooping has been investigated to assess hardware and software requirements to implement such a system. The results have shown that this controller forces the inverters to share active power equitably, but good reactive power sharing requires a higher output inductor than that used in the current system.
15
Mupparty, Durga Bhavani. "CAPACITOR SWITCHING TRANSIENT MODELING AND ANALYSIS ON AN ELECTRICAL UTILITY DISTRIBUTION SYSTEM USING SIMULINK SOFTWARE." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_theses/82.
Повний текст джерелаАнотація:
The quality of electric power has been a constant topic of study, mainly because inherent problems to it can bring great economic losses in industrial processes. Among the factors that affect power quality, those related to transients originated from capacitor bank switching in the primary distribution systems must be highlighted. In this thesis, the characteristics of the transients resulting from the switching of utility capacitor banks are analyzed, as well as factors that influence there intensities. A practical application of synchronous closing to reduce capacitor bank switching transients is presented. A model that represents a real distribution system 12.47kV from Shelbyville sub-station was built and simulated using MATLAB/SIMULINK software for purposes of this study. A spectral analysis of voltage and current waves is made to extract the acceptable capacitor switching times by observing the transient over-voltages and, harmonic components. An algorithm is developed for practical implementation of zero-crossing technique by taking the results obtained from the SIMULINK model.
16
Ali, Awab A. "A HYBRID FLYBACK LED DRIVER WITH UTILITY GRID AND SOLAR PV INTERFACE." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1515757861095375.
Повний текст джерела
17
Souare, Moussa. "Efficient Way of Reading Rotary Dial Utility Meter Using Image Processing." Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1258511722.
Повний текст джерелаАнотація:
Thesis(M.S.)--Case Western Reserve University, 2009Title from PDF (viewed on 2010-01-28) Department of Electrical Engineering and Computer Science -- Electrical Engineering Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center
18
Etawil, Hussein. "Convex Optimization and Utility Theory: New Trends in VLSI Circuit Layout." Thesis, University of Waterloo, 1999. http://hdl.handle.net/10012/813.
Повний текст джерелаАнотація:
The design of modern integrated circuits is overwhelmingly complicated due to the enormous number of cells in a typical modern circuit. To deal with this difficulty, the design procedure is broken down into a set of disjoint tasks. Circuit layout is the task that refers to the physical realization of a circuit from its functional description. In circuit layout, a connection-list called netlist of cells and nets is given. Placement and routing are subtasks associated with circuit layout and involve determining the geometric locations of the cells within the placement area and connecting cells sharing common nets. In performing the placement and the routing of the cells, minimum placement area, minimum delay and other performance constraints need to be observed. In this work, we propose and investigate new approaches to placement and routing problems. Specifically, for the placement subtask, we propose new convex programming formulations to estimate wirelength and force cells to spread within the placement area. As opposed to previous approaches, our approach is partitioning free and requires no hard constraints to achieve cell spreading within the placement area. The result of the global optimization of the new convex models is a global placement which is further improved using a Tabu search based iterative technique. The effectiveness, robustness and superiority of the approach are demonstrated on a set of nine benchmark industrial circuits. With regard to the routing subtask, we propose a hybrid methodology that combines Tabu search and Stochastic Evolution as a search engine in a new channel router. We also propose a new scheme based on Utility Theory for selecting and assigning nets to tracks in the channel. In this scheme, problem-domain information expressed in the form of utility functions is used to guide the search engine to explore the search space effectively. The effectiveness and robustness of the approach is demonstrated on five industrial benchmarks.
19
Bergey, Paul K. "A Decision Support System for the Electrical Power Districting Problem." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/27347.
Повний текст джерелаАнотація:
Due to a variety of political, economic, and technological factors, many national electricity industries around the globe are transforming from non-competitive monopolies with centralized systems to decentralized operations with competitive business units. This process, commonly referred to as deregulation (or liberalization) is driven by the belief that a monopolistic industry fails to achieve economic efficiency for consumers over the long run. Deregulation has occurred in a number of industries such as: aviation, natural gas, transportation, and telecommunications. The most recent movement involving the deregulation of the electricity marketplace is expected to yield consumer benefit as well.
To facilitate deregulation of the electricity marketplace, competitive business units must be established to manage various functions and services independently. In addition, these business units must be given physical property rights for certain parts of the transmission and distribution network in order to provide reliable service and make effective business decisions. However, partitioning a physical power grid into economically viable districts involves many considerations. We refer to this complex problem as the electrical power districting problem.
This research is intended to identify the necessary and fundamental characteristics to appropriately model and solve an electrical power districting problem. Specifically, the objectives of this research are five-fold. First, to identify the issues relevant to electrical power districting problems. Second, to investigate the similarities and differences of electrical power districting problems with other districting problems published in the research literature. Third, to develop and recommend an appropriate solution methodology for electrical power districting problems. Fourth, to demonstrate the effectiveness of the proposed solution method for a specific case of electric power districting in the Republic of Ghana, with data provided by the World Bank. Finally, to develop a decision support system for the decision makers at the World Bank for solving Ghana's electrical power districting problem.
Ph. D.
20
Jamil, Mohsin. "Repetitive current control of two-level and interleaved three-phase PWM utility connected converters." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/301402/.
Повний текст джерелаАнотація:
This thesis is mainly concerned with investigations into digital repetitive current control of two-level and interleaved utility connected PWM converters. The research is motivated by the relatively poor performance of classical (PI) controllers when the utility voltage harmonic distortion is high. This is due to the low gain, and poor disturbance rejection of the PI controller at the utility harmonic frequencies. Repetitive feedback controllers have the ability to track or reject periodic disturbances, such as utility harmonics, as they naturally have high gains at the utility voltage harmonic frequencies, assuming that these frequencies do not change. Repetitive controllers (RC) are known for being sensitive to variations in system parameters and disturbance frequency, which in practice renders them either ineffective or unstable. Another challenge arises from the memory requirements of RC in case of the absence of even harmonics, which can make its practical implementation difficult and expensive. In addition, another problem that has not been investigated extensively in the literature is that the effectiveness of RC is severely limited by the limited bandwidth of the plant (the utility connected converter and its filter). Theoretical analysis and simulation results presented in this thesis show that RC could not effectively reject disturbances at frequencies above the closed loop system bandwidth. The design of the converter's output filter bandwidth and the values of its components need to be selected carefully, to enable RC to be used effectively. The research in this thesis focuses on investigating the practical implementation and performance limits of two types of repetitive controllers (conventional and oddharmonics), used for current control of two-level utility connected converter with LCL output filter. The odd-harmonic repetitive controller halves the memory requirement and offers higher gains only at odd harmonic frequencies of interest. The overall control scheme consists of the traditional classical tracking controller with a dual loop feedback system and RC. The results indicate that the repetitive controller improves the steady state error and the total harmonic distortion of the output current, provided that the plant's bandwidth is sufficiently large. Finally, a repetitive controller for an interleaved utility connected converter has been designed and investigated in this study. The interleaved converter system has higher bandwidth than the two-level converter, which improves the effectiveness of RC. It provides good disturbance rejection compared to classical controllers which results in low output current THD. The RC was demonstrated to be robust despite uncertainty in utility impedance, while achieving a fast almost zero error convergence. The proposed RC has been experimentally implemented using a DSP and the results indicate that the quality of output current complies with international standards on harmonic limits and matches simulation results obtained from the Matlab/Simulink model of the system.
21
Palle, Sreeshailam. "Voltage Harmonic Control of Weak Utility Grid Through Distributed Energy Systems." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1344998933.
Повний текст джерела
22
NICOLAU, CAROLINA TEIXEIRA. "MEASUREMENT OF ELECTRICAL ENERGY: IMPACTS OF THE TECHNOLOGICAL CHANGED INTRODUCED IN THE LEGAL DEPARTMENT OF AN ELECTRICITY UTILITY." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2013. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=22994@1.
Повний текст джерелаАнотація:
A presente pesquisa de mestrado se desenvolve no contexto de um amplo programa estimulado pelo organismo regulador do setor elétrico brasileiro no âmbito do qual concessionárias brasileiras distribuidoras de energia elétrica desenvolvem seus projetos eficiência energética. Mais especificamente, o
trabalho tem por objetivo analisar os impactos que resultam da introdução de inovação tecnológica (troca de medidores eletromecânicos por medidores eletrônicos) no setor jurídico dessas empresas tendo em vista que a tecnologia de medição possui influência no faturamento dos clientes e na sua relação com a
concessionária. O impacto estudado refere-se (i) à quantidade de entrada de processos (no contencioso de massa do departamento jurídico da concessionária) e (ii) aos custos adicionais que passam a ser gerados pela introdução dessa alternativa tecnológica na medição de energia elétrica. Fazendo uso da
metodologia por séries temporais, modelos de previsão univariados, amortecimento exponencial, e modelos de regressão dinâmica, o trabalho inclui um estudo de caso de uma empresa distribuidora de energia. Como resultado, o trabalho mostra que os modelos de regressão dinâmica mostram-se mais eficazes. A partir dos modelos gerados, foi possível comprovar e quantificar o impacto da mudança da tecnologia de medição na quantidade de entrada de processos de reclamação sobre fatura no contencioso geral de massa.This Master dissertation is developed in the context of a broader program stimulated by the regulatory body of the Brazilian electrical sector under which Brazilian electricity distributors develop their energy efficiency projects. More specifically, the study aims to analyze the impacts that result from the introduction of technological innovation (replacement of electromechanical meters by electronic meters) in the legal departments of these companies with a view that measuring technology does have influence on customer billing and on its relationship with the electricity utility. The impact study refers (i) to the amount of input processes (mass litigation in the legal department of the utility) and (ii) to the additional costs generated by the introduction of this alternative technology in electricity metering. Making use of the time series methodology, forecasting univariate models, exponential smoothing, and dynamic regression models, the work includes a case study of an energy company. As a result, the work shows that the dynamic regression models are even more effective. From the generated models, it was possible to demonstrate and quantify the impact of the change in the measurement technology on the amount of input processes named invoice complaint on mass general litigation.
23
Carroll, Brandon T. "Using Motion Fields to Estimate Video Utility and Detect GPS Spoofing." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3291.
Повний текст джерелаАнотація:
This work explores two areas of research. The first is the development of a video utility metric for use in aerial surveillance and reconnaissance tasks. To our knowledge, metrics that compute how useful aerial video is to a human in the context of performing tasks like detection, recognition, or identification (DRI) do not exist. However, the Targeting Task Performance (TTP) metric was previously developed to estimate the usefulness of still images for DRI tasks. We modify and extend the TTP metric to create a similar metric for video, called Video Targeting Task Performance (VTTP). The VTTP metric accounts for various things like the amount of lighting, motion blur, human vision, and the size of an object in the image. VTTP can also be predictively calculated to estimate the utility that a proposed flight path will yield. This allows it to be used to help automate path planning so that operators are able to devote more of their attention to DRI. We have used the metric to plan and fly actual paths. We also carried out a small user study that verified that VTTP correlates with subjective human assessment of video. The second area of research explores a new method of detecting GPS spoofing on an unmanned aerial system (UAS) equipped with a camera and a terrain elevation map. Spoofing allows an attacker to remotely tamper with the position, time, and velocity readings output by a GPS receiver. This tampering can throw off the UAS's state estimates, but the optical flow through the camera still depends on the actual movement of the UAS. We develop a method of detecting spoofing by calculating the expected optical flow based on the state estimates and comparing it against the actual optical flow. If the UAS is successfully spoofed to a different location, then the detector can also be triggered by differences in the terrain between where the UAS actually is and where it thinks it is. We tested the spoofing detector in simulation, and found that it works well in some scenarios.
24
Kwa, Teik Lim. "NOVEL ON-LINE TRUE STRESS-STRAIN-ELECTRICAL CONDUCTIVITYUNIAXIAL TENSILE STRETCHING SYSTEM AND ITS UTILITY ON ELECTRICALLYCONDUCTIVE POLYLACTIC ACID (PLA) NANOCOMPOSITES." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1143663747.
Повний текст джерела
25
Chen, Penghao. "Improvement of the Operating Efficiency and Initial Costs of a Utility-Scale Photovoltaic Array through Voltage Clamping." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1333654173.
Повний текст джерела
26
Vasileiadis, Dimitrios. "Implementation of a reference model of a typical IT infrastructure of the office network of a power utility company." Thesis, KTH, Elkraftteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-203507.
Повний текст джерелаАнотація:
Power utility companies are really important in our daily routine since theyprovide us with power delivery, which is essential in today's society. Withthe advance of technology, a lot of the procedures that were being manuallydone by these companies to deliver electrical power, have been automated andcentrally controlled by Supervisory Control And Data Acquisition (SCADA)systems. Therefore, this automation must be protected from external attackersthat want to hurt control systems (e.g. SCADA), either by stealing sensitivedata or even by getting control of the control system and changing parametersand functions that are essential for the good and healthy function of thesesystems. Exploiting vulnerabilities in the oce network can bring an adversarya step closer in getting access to the control system. It is not sucient onits own, but the adversary can launch further attacks from there targeting thecontrol system.The aim of this thesis is to construct a reference model of a typical IT infrastructureof the oce network of a power utility company, with a simpliedimplementation in CRATE. CRATE (Cyber Range And Training Environment)is the environment that was used for the implementation of the thesis, providedby the Swedish Defense Research Agency [FOI]. After the implementation isnished, a SCADA system of an enterprise will be installed in CRATE and willbe connected with this oce network. Once this is done, the Swedish DefenseResearch Agency will simulate cyber-attacks in a more complete infrastructure.The point of this thesis is to make the oce infrastructure as close to a real enterprisenetwork, although there with some dierentiation, part of it on purposeand part of it due to some limitations.Elbolags existens är essentiell i dagens samhälle med tanke på att elbolagenlevererar el vilket viktiga samhällsfunktioner beror på. Idag har avanceradteknologi gjort det möjligt att konvertera diverse procedurer som tidigare genomförts manuellt för att leverera elektricitet att genomföras automatiserat ochcentralstyrt via systemet Supervisory Control And Data Acquisition (SCADAsystem).Det är därför ytterst viktigt att skydda det automatiserade systemetfrån externa angripare d.v.s. IT-intrång som vill skada det använda styrsystemett.ex. SCADA-styrsystem. Skada kan ske antingen genom att stjälakänsliga uppgifter eller få kontroll över styrsystemet och ändra på parametraroch funktioner som är väsentliga för ett välfungerande system. Att exploaterasårbarheter i kontorsnätverk kan mojliggöra att motståndare hamnar ett stegnärmare att få tillgång till styrsystemet.Syftet med denna studie är att konstruera en referensmodell av en typisk ITinfrastrukturav kontorsnätet på ett elbolag med en förenklad tillämpning inomCyber Range And Training Environment (CRATE). CRATE är en miljö förcyberövningar som tillhandahålls av Totalförsvarets Forskningsinstitut (FOI)och som har använts i denna studie för att implementera referensmodellen.När referensmodellen av kontorsnätet har implementerats, installeras det ävenett SCADA-system i CRATE, och dessa kopplas tillsammans. Därmed skaFOI kunna simulera cyberattacker i en mer komplett infrastruktur. Syftet meddenna studie var att skapa ett så pass verkligt kontorsnät som möjligt trots vissdifferentiering jämfört med verkligheten på grund av bl.a. vissa begräsningar.
27
Roseveare, Nicholas. "Optimization and resource management in wireless sensor networks." Diss., Kansas State University, 2013. http://hdl.handle.net/2097/15730.
Повний текст джерелаАнотація:
Doctor of PhilosophyDepartment of Electrical and Computer Engineering
Balasubramaniam Natarajan
In recent years, there has been a rapid expansion in the development and use of low-power, low-cost wireless modules with sensing, computing, and communication functionality. A wireless sensor network (WSN) is a group of these devices networked together wirelessly. Wireless sensor networks have found widespread application in infrastructure, environmental, and human health monitoring, surveillance, and disaster management. While there are many interesting problems within the WSN framework, we address the challenge of energy availability in a WSN tasked with a cooperative objective. We develop approximation algorithms and execute an analysis of concave utility maximization in resource constrained systems. Our analysis motivates a unique algorithm which we apply to resource management in WSNs. We also investigate energy harvesting as a way of improving system lifetime. We then analyze the effect of using these limited and stochastically available communication resources on the convergence of decentralized optimization techniques. The main contributions of this research are: (1) new optimization formulations which explicitly consider the energy states of a WSN executing a cooperative task; (2) several analytical insights regarding the distributed optimization of resource constrained systems; (3) a varied set of algorithmic solutions, some novel to this work and others based on extensions of existing techniques; and (4) an analysis of the effect of using stochastic resources (e.g., energy harvesting) on the performance of decentralized optimization methods. Throughout this work, we apply our developments to distribution estimation and rate maximization. The simulation results obtained help to provide verification of algorithm performance. This research provides valuable intuition concerning the trade-offs between energy-conservation and system performance in WSNs.
28
Raab, Jonathan David. "Consensus-building in electric utility regulation." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/28010.
Повний текст джерела
29
Schenler, Warren William. "Full value estimation of electric utility options." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/46063.
Повний текст джерела
30
Shimaya, Katsunori. "Japanese electric utility planning under regulatory transition." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10932.
Повний текст джерела
31
Atcitty, Stanley. "Electrochemical Capacitor Characterization for Electric Utility Applications." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/29613.
Повний текст джерелаАнотація:
Electrochemical capacitors (ECs) have received a significant level of interest for use in the electric utility industry for a variety of potential applications. For example, ECs integrated with a power conversion system can be used to assist the electric utility by providing voltage support, power factor correction, active filtering, and reactive and active power support. A number of electric utility applications have been proposed but, to date, ECs have not been very well characterized for use in these applications. Consequently, there is a need to gain a better understanding of ECs when used in electric utility applications. ECs are attractive for utility applications because they have higher energy density than conventional capacitors and higher power density than batteries. ECs also have higher cycle life than batteries, which results in longer life spans. To better understand the system dynamics when ECs are used for utility applications requires suitable models that can be incorporated into the variety of software programs currently used to create dynamic simulations for the applications, programs such as PSPICEâ ¢, MATLAB Simulinkâ ¢, and PSCADâ ¢. To obtain a relevant simulation with predictive capability, the behavior of the EC on which the model is based must be well defined; this necessitates a thorough understanding of the electrical characteristics of these devices.
This paper and the associated research focus on the use of the electrochemical impedance spectroscopy (EIS) to develop nonlinear equivalent circuit models to better understand and characterize symmetric ECs (SECs) for electric utility applications. It also focuses on the development of analytical solutions to better understand SEC efficiency and energy utilization.
Representative static synchronous compensator (StatCom) systems, with and with out SECs, were simulated and discussed. The temperature effects on device ionic resistance and capacitance are covered as is the effect of temperature on maximum power transfer to a resistive load. Experimental data showed that the SEC's double-layer capacitance and ionic resistance are voltage dependent. Therefore a voltage-dependent RC network model was developed and validated and the results showed that this type of model mimicked the experimental SEC better than traditional electrical models. Analytical solutions were developed for the efficiency and energy utilization of an SEC. The analytical solutions are a function of operating voltages, constant current, and ionic resistance. The operating voltage method is an important factor in system design because the power conversion interface is typically limited by a voltage window and thus can determine the performance of SECs during charge and discharge. If the operating voltage window is not properly selected the current rating of the system can be reduced thus limiting the SECs performance.Ph. D.
32
Chuk, Joseph R. "Electric utility corporate goals in employee television programs." Instructions for remote access. Click here to access this electronic resource. Access available to Kutztown University faculty, staff, and students only, 1987. http://www.kutztown.edu/library/services/remote_access.asp.
Повний текст джерелаАнотація:
Thesis (M.S.)--Kutztown University of Pennsylvania, 1987.Source: Masters Abstracts International, Volume: 45-06, page: 2706. Typescript. Abstract precedes thesis as [2] preliminary leaves. Includes bibliographical references (leaves 55-56).
33
Ingram, Christopher Thomas. "Electric utility storm restoration : crew work allocation optimization." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105631.
Повний текст джерелаАнотація:
Thesis: S.M. in Engineering Systems, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, 2016. In conjunction with the Leaders for Global Operations Program at MIT.Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2016. In conjunction with the Leaders for Global Operations Program at MIT.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 55-56).
Storms damage Atlantic Electric's electric distribution network, resulting in power outages and expensive repairs. After severe storms Atlantic Electric hires external contractor crews to perform the majority of the restoration work. This project focuses on increasing the effectiveness of contractor crews by: 1) improving work flow processes that can result in restoration delays; 2) staging contractor crews at operations bases that are close to damage; and 3) optimizing the work allocation to contractor crews so that customers have their power restored sooner. An optimization model used by Atlantic Electric to pre-stage their crews is modified and improved so that it can suggest locations for staging crews throughout a restoration effort. The model compares well to actual storm assignments in previous storms, normally preempting Atlantic Electric's decision by one day. This suggests that Atlantic Electric's experts and storm managers are already operating efficiently, but that the model can help them reach their decisions faster since it incorporates all data instantaneously and objectively. The use of the model will also provide a valuable justification to the state regulators, who monitor storm responses, for crew movements and postings. Next, an optimization model is developed to improve the assignment of individual repair jobs to crews. Currently the process is performed manually and can vary from base to base. Decision makers must balance multiple factors, such as the number of crews available, location of damage points, the severity of the damage, and the number and type of customers without power. Under enormous pressure in a hectic environment, it can be difficult to analyze and weigh all these factors. Additionally, due to the infrequent nature of these large events, some personnel have limited firsthand experience in these situations, while others are extremely experienced and skilled. The model captures and codifies the methodology of Atlantic Electric's storm experts and provides a quick, consistent tool for assigning work efficiently. Finally, we suggest several process improvements to the contractor work flow.
by Christopher Thomas Ingram.
S.M. in Engineering Systems
M.B.A.
34
Staschus, Konstantin. "Renewable energy in electric utility capacity planning: a decomposition approach with application to a Mexican utility." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/53898.
Повний текст джерелаАнотація:
Many electric utilities have been tapping such energy sources as wind energy or conservation for years. However, the literature shows few attempts to incorporate such non-dispatchable energy sources as decision variables into the long-range planning methodology. In this dissertation, efficient algorithms for electric utility capacity expansion planning with renewable energy are developed.
The algorithms include a deterministic phase which quickly finds a near-optimal expansion plan using derating and a linearized approximation to the time-dependent availability of non-dispatchable energy sources. A probabilistic second phase needs comparatively few computer-time consuming probabilistic simulation iterations to modify this solution towards the optimal expansion plan.
For the deterministic first phase, two algorithms, based on a Lagrangian Dual decomposition and a Generalized Benders Decomposition, are developed. The Lagrangian Dual formulation results in a subproblem which can be separated into single-year plantmix problems that are easily solved using a breakeven analysis. The probabilistic second phase uses a Generalized Benders Decomposition approach. A depth-first Branch and Bound algorithm is superimposed on the two-phase algorithm if conventional equipment types are only available in discrete sizes. In this context, computer time savings accrued through the application of the two-phase method are crucial.
Extensive computational tests of the algorithms are reported. Among the deterministic algorithms, the one based on Lagrangian Duality proves fastest. The two-phase approach is shown to save up to 80 percent in computing time as compared to a purely probabilistic algorithm.
The algorithms are applied to determine the optimal expansion plan for the Tijuana-Mexicali subsystem of the Mexican electric utility system. A strong recommendation to push conservation programs in the desert city of Mexicali I results from this implementation.Ph. D.
35
Jewczyn, Nicholas Stephen. "Relative Pricing of Publicly Traded U.S. Electric Utility Companies." Thesis, Walden University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3594929.
Повний текст джерелаАнотація:
In the financial turmoil of 2008, U.S. firms reported debt-ratios that differed from the debt-ratios calculated from balance sheets. The problem is that investors bought common stock expecting initial investment return and lost money when companies delisted. The purpose of this quantitative study was to determine sample securities pricing with the application of synthetic assets and debt accrued. Addressed in the research questions was whether those securities were (a) underpriced compared with return-on-assets (ROA), (b) overpriced compared with ROA, (c) a debt-ratio higher than 60% and also overpriced, (d) underpriced with a synthetic asset added, or (e) related by relative pricing to variant pricing and market capitalization. The study's base theory was Pan's efficient market hypothesis (EMH) of security price prediction of market prices versus model prices. The data from the financial statements of 16 publicly traded U.S. electric utility companies were analyzed via correlations and multiple regression analyses to determine securities pricing and suitability. The findings from the analyses of the sample's variables of market price, book value, market-to-book, and study constructed variables from those variable data were statistically significant. The alternate hypotheses were accepted for all 5 research questions since the analytical operationalization of the hypothetical constructs led to significant relationships. Results suggest that the use of more pricing determinants in securities evaluation may lead to investors losing less money and earning the expected returns for a more efficient capital market, leading to a stronger economy and macroeconomic stability.
36
McElhaney, Steven Hunt. "Defining display complexity in electric utility system operator displays." Thesis, Mississippi State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3603464.
Повний текст джерелаАнотація:
In the electric utility industry, displays provide power system operators with information on and the status of the system, who then make decisions on how to maintain the safety, the reliability and the efficient operation of the utility generation and transmission grid based on that information. Complexity of the data presented and the display itself can lead to errors or misjudgments that can cause power system operators to make unwise decisions. The primary goal of this research was to develop a method to quantify display complexity for select displays used by system operators when operating the electric generation and transmission grids. Three studies were performed: (1) complexity measure development, (2) validation of the measure using usability and situation awareness (SA) techniques, and (3) display revisions based on complexity measure findings. Fifteen 15 different complexity metrics were originally considered (additive models, multiplicative models, and combination models with five different weighting schemes). The additive model with equal weighting was found to be the most sensitive in differentiating displays and was used in the later studies. For the validation study, system operators were asked to complete a usability questionnaire and a paper-based SA test using the current displays. Correlation and scatter plot analyses was used to determine if the complexity metric and usability and SA scores were related. Results of the validation study indicated that usability and SA scores for the studied displays were not well correlated with the complexity metric. In study 3, the highest and lowest scoring displays were redesigned with an emphasis on maintaining functionality but reducing aspects of complexity that were driving the complexity score. Systems operators again completed the usability and SA testing using the redesigned displays and again correlation analysis was performed. As was the case with study 2, usability scores were not correlated with the complexity metric; however, SA scores were significantly correlated. The complexity metric developed here can be used to quantify the complexity in a display and identify redesign opportunities to reduce non-essential information, as displays that are less complex should result in improved operator performance and satisfaction with the display.
37
Higbee, Melissa (Melissa Aura). "Climate change adaptation in the U.S. electric utility sector." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81632.
Повний текст джерелаАнотація:
Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 95-101).
The electric utility sector has been a focus of policy efforts to reduce greenhouse gas emissions, but even if these efforts are successful, the sector will need to adapt to the impacts of climate change. These are likely to include increased heat waves, drought, extreme precipitation events, and sea level rise. Electric utilities play a key role in providing electricity services in cities that will be facing all of these difficulties. Cities depend on electricity service for public health, safety and economic development. This thesis examines how electric utilities in the United States are approaching climate change adaptation and the factors enabling and constraining these efforts. The thesis draws on an analysis of electric utility responses to surveys distributed by the Carbon Disclosure Project as well as case studies of Consolidated Edison, Entergy, and Pacific Gas & Electric. The case study utilities are incorporating climate change projections into their risk management and capital planning activities. Integrating climate change projections into risk management efforts helps utilities use replacement opportunities to build greater resilience into infrastructure systems and ensure that adaptation strategies take competing demands on resources into account. Both approaches to adaptation are generally recommended by adaptation experts. However, existing internal decisionmaking may not be well suited for incorporating the uncertainties of climate change impacts. The case study utilities could be using Scenario Planning to develop strategies likely to be effective given a range of possible futures, but they are not. I argue that state utility regulatory commissions should consider taking a more active role in providing guidance and oversight to utilities regarding climate change adaptation. They should consider (1) requiring utilities to submit climate change vulnerability assessments and detailed adaptation plans; (2) incorporating climate change risk and adaptation considerations into existing electricity plans; and (3) convening joint climate change planning efforts with utilities, municipal governments, and a range of other stakeholders. Cities and states that would like to see electric utilities put more emphasis on climate change adaptation should consider sharing climate change projections and forecasts of potential climate change impacts. Provision of such information has been effective in encouraging adaptation planning in the case studies. The actual adaptation strategies that utilities have adopted depend largely on the risks they face and the regulatory and policy environment in which they find themselves.
by Melissa Higbee.
M.C.P.
38
Jewczyn, Nicholas Stephen. "Relative Pricing of Publicly Traded U.S. Electric Utility Companies." ScholarWorks, 2011. https://scholarworks.waldenu.edu/dissertations/1076.
Повний текст джерелаАнотація:
In the financial turmoil of 2008, U.S. firms reported debt-ratios that differed from the debt-ratios calculated from balance sheets. The problem is that investors bought common stock expecting initial investment return and lost money when companies delisted. The purpose of this quantitative study was to determine sample securities pricing with the application of synthetic assets and debt accrued. Addressed in the research questions was whether those securities were (a) underpriced compared with return-on-assets (ROA), (b) overpriced compared with ROA, (c) a debt-ratio higher than 60% and also overpriced, (d) underpriced with a synthetic asset added, or (e) related by relative pricing to variant pricing and market capitalization. The study's base theory was Pan's efficient market hypothesis (EMH) of security price prediction of market prices versus model prices. The data from the financial statements of 16 publicly traded U.S. electric utility companies were analyzed via correlations and multiple regression analyses to determine securities pricing and suitability. The findings from the analyses of the sample's variables of market price, book value, market-to-book, and study constructed variables from those variable data were statistically significant. The alternate hypotheses were accepted for all 5 research questions since the analytical operationalization of the hypothetical constructs led to significant relationships. Results suggest that the use of more pricing determinants in securities evaluation may lead to investors losing less money and earning the expected returns for a more efficient capital market, leading to a stronger economy and macroeconomic stability.
39
Babin, Anthony. "Optimisation du coût de revient global (TCO) d’un véhicule utilitaire électrique 3,5t ; modélisation multi-physique, dimensionnement et recharge intelligente." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS356.
Повний текст джерелаАнотація:
Le véhicule électrique est une des solutions de transport respectueuses de l’environnement, n’émettant pas de polluant lors de son utilisation. Gruau, constructeur carrossier pour véhicules utilitaires, se lance activement dans le transport écologique sur le segment de l’utilitaire 3,5t. Afin d’accroitre les ventes de véhicules utilitaires électriques, il est nécessaire d’en réduire le coût total de possession (ou TCO (Total Cost of Ownership)). L’objectif de cette thèse est d’étudier et de modéliser le comportement des composants de ce véhicule électrique pour simuler des calculs de TCO. Le composant principal étudié est la batterie, dont la durée de vie limitée conditionne la rentabilité du véhicule. La première partie des travaux fut consacrée à la modélisation du comportement du véhicule en fonction d’une mission client donnée. Une étude des cellules de batterie est réalisée dans le but de construire un modèle multi-physique complet en prenant en considération le vieillissement calendaire et le vieillissement en cyclage. Un modèle énergétique global, comprenant ce modèle batterie, permet de déterminer l’énergie nécessaire pour un parcours donné et de simuler le vieillissement des cellules électrochimiques afin de calculer le TCO. Une seconde partie est orientée vers le calcul du TCO. La mise en oeuvre d’un algorithme d’optimisation avec une méthodologie d’accélération des calculs a permis de réaliser les calculs dans des temps raisonnables (passage de 13h à 15min par itération). Après étude de l’impact du dimensionnement de la batterie sur le TCO, il en ressort que la réduction de la capacité n’entraine pas systématiquement la réduction du TCO. Il existe pour chaque mission un point de TCO optimal (jusqu’à 17% d’éconnomie). Afin d’améliorer le TCO, des stratégies de recharge intelligentes sont élaborées et permettent rentabilité accrue du VUE (jusqu’à 29%). Ce travail a été intégré dans un logiciel d’aide à la décision de la capacité de la batterie suivant les besoins du client, destiné aux forces de ventes commercialesThe electric vehicle is one of the environmentally friendly transport solutions that emit no pollutant during its use. Gruau, manufacturer-converter for light commercial vehicles (LCV), is actively involved in green transport in the 3.5t segment. In order to increase sales of electric LCV, it is necessary to reduce its total cost of ownership (TCO). The objective of this thesis is to study and model the behavior of the components of this electric vehicle in order to simulate TCO. The main component studied is the battery, whose limited lifetime will determine the profitability of the vehicle. The first part of the work was devoted to modeling the behavior of the vehicle according to a given customer mission. The study of battery cells was done with the aim of building a complete multi-physics model taking into account calendar aging and cycling aging. Then, this battery model is integrated in a complete energy model taking into account all the components of the studied vehicle. Then a global model, including this battery model, makes it possible to determine the energy required for a given path and to simulate the aging of the electrochemical cells in order to calculate the TCO. A second part is oriented towards the calculation of the TCO. The implementation of an optimization algorithm, with a methodology of computing acceleration, allowed to achieve the computations in reasonable times (reduction from 13h to 15min by iteration). After studying the impact of battery sizing on the TCO, it appears that the reduction of the battery capacity does not systematically lead to the reduction of the TCO. There is therefore an optimum TCO point for each mission (up to 17% savings). In order to improve the TCO, smart recharging strategies are developed and allow increasing e-LCV profitability (up to 29%). This work is integrated into a decision support software relative to the battery capacity according to customer needs, intended for commercial sales forces
40
Gupta, Rajnish. "Economic impact of non-utility generation on electric power systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/nq23935.pdf.
Повний текст джерела
41
Lian, Carl Elling. "The effect of fuel adjustment clauses on electric utility production /." Thesis, Connect to this title online; UW restricted, 1987. http://hdl.handle.net/1773/7407.
Повний текст джерела
42
Ouellette, Simon. "Investigating the development of a zero emission electric utility snowmobile." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32294.
Повний текст джерелаАнотація:
This thesis addresses the question: can an electric snowmobile be one of the solutions to help lower snowmobile emissions and energy consumption? In addressing this question the performance limitations of current electric snowmobile prototypes are investigated and it is shown that, unless a huge leap is seen in current battery technology energy density, electric snowmobiles cannot perform on par with gasoline snowmobile on both range and performance simultaneously. Despite this, electric snowmobiles do have a certain number of niche applications where they can be useful. This thesis suggests that electric snowmobile powetrain modeling and simulation for these niche applications can potentially help overcome some of the challenges that exist in implanting such a vehicle for regular use. A complete, virtual electric snowmobile model was built and validated using actual electric snowmobile on-snow test data. Snowmobile emission and energy consumption simulation was performed and demonstrated that Canadian electric snowmobile fuel cycle emissions and energy consumptions were, in general, substantially lower than gasoline snowmobiles. However, this is closely linked with electricity generation techniques and should not be extrapolated to say that this is the case for all potential electric snowmobiles worldwide.Cette thèse tente d'apporter réponse à la question suivante: est-ce que la motoneige électrique peut faire partie des solutions afin d'aider à diminuer les émissions et la consommation d'énergie des motoneiges? Afin de répondre à cette question, un questionnement sur les performances des prototypes de motoneiges électriques actuelles est entrepris et il en ressort qu'à moins qu'une énorme percée technologique ne vienne changer la donne, la densité d'énergie des technologies de piles présentement disponibles fait en sorte qu'une motoneige électrique ne peux pas envisager performer de façon similaire à une motoneige conventionnelle à essence sur le plan de l'autonomie et de la performance de façon simultanée. Ceci étant dit, il existe tout de même des applications de niche pour lesquelles une motoneige électrique est parfaitement apte à accomplir le travail requis. Cette thèse suggère que l'utilisation de la modélisation et de la simulation peut s'avérer un outil précieux afin de surmonter certains obstacles à l'implantation de motoneiges électriques. Un modèle virtuel de motoneige électrique est assemblé et une simulation virtuelle est complétée et ensuite validée en utilisant des données obtenues lors d'essais sur neige avec une vraie motoneige électrique. Une simulation est faite et permet de démontrer que sur la totalité de son cycle de carburant, une motoneige électrique canadienne émet généralement moins d'émissions et consomme moins d'énergie qu'une motoneige conventionnelle à essence, et ce, de façon substantielle. Cependant, puisque ce résultat est fortement lié aux méthodes de production d'énergie il ne peu
43
Dippold, David George. "Integrating environmental and competitive considerations in electric utility operational planning /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487929745334352.
Повний текст джерела
44
Cain, Mary B. "Valuation of electric utility generating assets in a competitive environment." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1865.
Повний текст джерела
45
Solum, Erik. "Achieving over-the-wire configurable confidentiality, integrity, authentication and availability in GridStat's status dissemination." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Fall2007/e_solum_121807.pdf.
Повний текст джерела
46
Sung, Martin (Ming-Che). "The perception and management of pollution risks in Taiwan's electric utility." Thesis, Glasgow Caledonian University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313175.
Повний текст джерелаАнотація:
This thesis is the study of the perception and management of pollution risks in Taiwan's electric utility in terms of a social science paradigm of risk. It represents the first examination of Feng Shui belief impact on Taiwanese risk behaviour in electric risk settings. The deep seated culture and widespread practice of Feng Shui in traditional Chinese society would lead to the assumption that Feng Shui belief should strongly influence Taiwan risk behaviour. This empirical study research revealed that Feng Shui belief is much less important to Taiwanese risk behaviour than might have been thought. Most of the variation in electric risk acceptability resulted from the influence of social equity and justice. This study also examined the literature between Feng Shui and risk. What emerged from this is the notion that Feng Shui can be regarded as helpful complementary thinking in a social science paradigm of risk. This study suggests a number of important implications for Taipower Company and risk regulators. The choice about siting of a power plant should take account of the concept of Feng Shui the boundary rather than the concept of the fixed and administrative boundary. Implication also emerged in relation to social trust and the understanding of local residents' risk perception
47
Lim, Sungmin. "Electricity privatization : should South Korea privatize its state-owned electric utility?" Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/67250.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 77-80).
The state-owned electric utility, Korea Electricity Power Cooperation (KEPCO), privatization has been a key word in South Korea since 1997, when the government received $55 billion from the International Monetary Fund in exchange for a tough economic restructuring that included massive privatization. The Korean government separated KEPCO's six generation subsidiaries from KEPCO in 2001 in the initial process of the privatization. However, the government has not taken any further action since then. While there have been debates about the privatization of KEPCO, the debates were political rather than economic. This thesis will investigate whether or not Korea should continue to privatize KEPCO. First, it will examine how much revenue the government can make by selling its shares of KEPCO. Second, this thesis will study how much investment a privatized electricity industry will attract after privatization. Third, it will identify whether the electricity price will go down if the government privatizes KEPCO. Fourth, it will assess how the relationship between the government and the industry will change after privatization. Finally, it will identify how much does the government and people have to pay for the transition, which is caused by the change from a monopoly to a competitive market. By comparing the advantages and the disadvantages, this thesis will decide whether the advantages outweigh the disadvantages. This thesis will discuss only economic aspects; it will not examine the political, social and cultural aspects which are difficult to measure objectively.
by Sungmin Lim.
S.M.
48
Sun, Jiong. "Football on mobile phones : algorithms, architectures and quality of experience in streaming video." Doctoral thesis, Umeå : Department of Applied Physics and Electronics, Umeå University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-831.
Повний текст джерела
49
Slavickas, Rimas Anthony. "Trade-off decisions in distribution utility mangement /." *McMaster only, 1998.
Знайти повний текст джерела
50
Mearns, Howard Andrew. "Design and testing of the WVU Challenge X competition hybrid diesel electric vehicle." Morgantown, W. Va. : [West Virginia University Libraries], 2009. http://hdl.handle.net/10450/10310.
Повний текст джерелаАнотація:
Thesis (M.S.)--West Virginia University, 2009.Title from document title page. Document formatted into pages; contains viii, 61 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 59-61).