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1
Kaseke, Nyasa. "An estimate of the cost of electricity outages in Zimbabwe." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1011119.
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This thesis estimates the cost of electricity outages in Zimbabwe for the year 2009. Much reference is made to government, the power utility - Zimbabwe Electricity Supply Authority (ZESA) and other countries in the Southern African Power Pool (SAPP), also experiencing electricity outages. An electricity outage is a complete loss of power supply to an area. An outage may result from planned or unplanned load shedding or faults. Load shedding is accelerated by power supply shortages. The shortages are experienced during peak demand times. In 2009, Zimbabwe’s peak demand was about 1574MW. ZESA had the capacity to supply 1080MW and imported 100MW (guaranteed from Mozambique), leaving a shortfall of 394MW. This shortfall is worsened by transmission losses (about 108MW) and consumption by ZESA properties (about 200MW) bringng down the supply to customers of about 700MW. The supply shortage is the result of a lack of investment in the power sector by government for expanded generation capacity, incorrect pricing, droughts, internal conflicts, skills flight, government energy sector regulation, vandalism of equipment and under supply of coal to thermal power stations. Consumers in all sectors are experiencing power outage incidences of different duration. The severity of the inconvenience depends on the load shedding time table, preferences of the power utility and arrangements that can be made with the utility. Power outages negatively affect (and result in cost to) the productive sectors (industry, mining and farming) and households. The main objective of the thesis is to estimate the cost of power outages to the sectors. Sub-objectives of the study include: to identify the main features of power crisis in Zimbabwe and government response to it with a regional power generated setting; to formulate a model that clearly identifies the different cost components of power outages in Zimbabwe; to identify appropriate methods by which to estimate these cost components; to estimate the cost of power outages to the productive sectors (mining, agriculture and industrial) and households of Zimbabwe; to critically analyse the credibility of these estimates, and to consider the saving of the costs of outages achieved through increased investment in generating capacity in Zimbabwe. ZESA undertook reforms (institutional and tariff) in order to improve management efficiencies and supply. It was divided into five entities resulting in management and financial improvement, but its reform of tariffs has been stiffled by subsidies and price regulations. ZESA adopted the cost plus rate of return pricing strategy in 2004 but regulation kept the tariff below cost. The regulation is pro-poor in aim but it encourages wasteful consumption. Similar supply shortages are affecting the whole SAPP group. The power pool load shed 758MW in 2009. In Zimbabwe alone load shedding was 315MW. In an attempt to solve the problem, member utilities engage in bilateral contacts and short-term trading through Short Term Energy Markets (STEM). A number of Southern African countries have to load shed - the average frequency being three to five (3-5) times per week for the region. A number of studies have been carried out by different scholars attempting to assess the impact and cost of outages. The general conclusion is that power outages cause significant costs to consumers, both direct and indirect. From a global perspective, the increase in the quality of electricity supplied has fallen behind the increase in quantity demanded, causing an increase of incidence in power outages. An analysis of Sub-Saharan Africa shows that the causes of supply shortages are natural (drought), oil price shocks, conflict and the lack of investment in generation capacity. This generates two outage cost estimates – a direct cost (welfare loss) and indirect cost (backup cost). The sum of these estimates is the total outage cost. The direct cost estimate is based on direct loss incurred during the power outages - lost production, lost materials, and lost time or leisure. In order to derive an estimated direct cost, it is necessary to obtain an accurate respondent self-assessment, which, in turn depends on the keeping of good records of hours of outages and losses incurred during outage times. The estimated indirect cost (backup cost) is derived from the cost of investment in backup sources and running of these sources as a mitigating measure during a power outage. The expected gain from self-generated kWh is assumed to be equal to the expected loss from the marginal kWh electricity not supplied by the utility (the outage). The annualised capital cost of backup source plus the variable cost of generating electricity by the backup source are another element of the cost of power outages. The prices of backup sources were obtained from the two leading retailers, Tendo Power and Ellis Electronics. To the extent that the captive generation includes investment in emergency or optional plant (as part of normal production infrastructure), it may overestimate cost.
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Fletcher, Robert Henry. "Optimal distribution system horizon planning /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/6018.
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Eyisi, Chiebuka. "Load Estimation for Electric Power Distribution Networks." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5935.
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In electric power distribution systems, the major determinant in electricity supply strategy is the quantity of demand. Customers need to be accurately represented using updated nodal load information as a requirement for efficient control and operation of the distribution network. In Distribution Load Estimation (DLE), two major categories of data are utilized: historical data and direct real-time measured data. In this thesis, a comprehensive survey on the state-of-the-art methods for estimating loads in distribution networks is presented. Then, a novel method for representing historical data in the form of Representative Load Curves (RLCs) for use in real-time DLE is also described. Adaptive Neuro-Fuzzy Inference Systems (ANFIS) is used in this regard to determine RLCs. An RLC is a curve that represents the behavior of the load during a specified time span; typically daily, weekly or monthly based on historical data. Although RLCs provide insight about the variation of load, it is not accurate enough for estimating real-time load. This therefore, should be used along with real-time measurements to estimate the load more accurately. It is notable that more accurate RLCs lead to better real-time load estimation in distribution networks.
This thesis addresses the need to obtain accurate RLCs to assist in the decision-making process pertaining to Radial Distribution Networks (RDNs).This thesis proposes a method based on Adaptive Neuro-Fuzzy Inference Systems (ANFIS) architecture to estimate the RLCs for Distribution Networks. The performance of the method is demonstrated and simulated, on a test 11kV Radial Distribution Network using the MATLAB software. The Mean Absolute Percent Error (MAPE) criterion is used to justify the accuracy of the RLCs.M.S.E.E.
Masters
Electrical Engineering and Computing
Engineering and Computer Science
Electrical Engineering
4
Yang, Xiaoguang Miu Karen Nan. "Unbalanced power converter modeling for AC/DC power distribution systems /." Philadelphia, Pa. : Drexel University, 2006. http://hdl.handle.net/1860/1231.
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Matavalam, Roop Kishore R. "Power distribution reliability as a function of weather." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0006668.
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Xia, Xiuxian. "Dynamic power distribution management for all electric aircraft." Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/6285.
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In recent years, with the rapid development of electric and electronic
technology, the All-Electric Aircraft (AEA) concept has attracted more and
more attention, which only utilizes the electric power instead of conventional
hydraulic and pneumatic power to supply all the airframe systems. To meet the
power requirements under various flight stages and operating conditions, the
AEA approach has resulted in the current aircraft electrical power generation
capacity up to 1.6 MW. To satisfy the power quality and stability requirements,
the advanced power electronic interfaces and more efficient power distribution
systems must be investigated. Moreover, with the purpose of taking the full
advantages of available electrical power, novel dynamic power distribution
management research and design for an AEA must be carried out.
The main objective of this thesis is to investigate and develop a methodology
of more efficient power distribution management with the purpose of
minimizing the rated power generating capacity and the mass of the electrical
power system (EPS) including the power generation system and the power
distribution system in an AEA. It is important to analyse and compare the
subsistent electrical power distribution management approaches in current
aircraft. Therefore the electrical power systems of A320 and B777, especially
the power management system, will be discussed in this thesis.
Most importantly the baseline aircraft, the Flying Crane is the outcome of the
group design project. The whole project began in March 2008, and ended in
September 2010, including three stages: conceptual design, preliminary
design and detailed design. The dynamic power distribution management
research is based on the power distribution system of the Flying Crane.
The main task of the investigation is to analyse and manage the power usage
among and inside typical airframe systems by using dynamic power
distribution management method. The characteristics and operation process of
these systems will be investigated in detail and thoroughly. By using the
method of dynamic power distribution management, all the electrical
consumers and sub-systems powered by electricity are managed effectively.
The performance of an aircraft can be improved by reducing the peak load
requirement on board. Furthermore, the electrical system architecture,
distributed power distribution system and the dynamic power distribution
management system for AEA are presented. Finally, the mass of the whole
electrical power system is estimated and analysed carefully.
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Kline, Daniel B. "Graphical modeling of shipboard electric power distribution systems." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA276742.
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Bertling, Lina. "Reliability-centred maintenance for electric power distribution systems." Doctoral thesis, KTH, Electrical Systems, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3391.
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Oka, Ashok A. "Reliability and restoration algorithms for electrical distribution systems." Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-08232007-111001/.
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Lee, Seung Jae. "Configuration control of distribution feeders in normal and emergency states /." Thesis, Connect to this title online; UW restricted, 1988. http://hdl.handle.net/1773/5923.
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Brown, Richard E. "Reliability assessment and design optimization in electric power distribution systems /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/6036.
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Morton, Anthony B. "Managed DC power reticulation systems /." Connect to thesis, 1999. http://eprints.unimelb.edu.au/archive/00000655.
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Chen, William Wen-Hou. "An auxiliary power distribution network for an electric vehicle." Thesis, University of Canterbury. Department of Electrical and Computer Engineering, 2003. http://hdl.handle.net/10092/2284.
Full textAbstract:
The University of Canterbury purchased a modern Toyota MR2 sports car with the
intention of converting it into an electric vehicle. Similar to the common combustion engine
vehicles, electric vehicles requires power and control systems to operate the 12Vdc
auxiliaries, such as lights, indicators and wipers. Traditional technology results in a large
number of wires in the wiring harness. To reduce the number of wires, an alternative
method is to use a pair of control lines and a universal power connection around the
vehicle. This power and control system is named the "Power Distribution Network" and it
is implemented by using multiple power converters and a differential control system.
This thesis presents the design, implementation, and test results of the Power
Distribution Network for the MR2. The 300Vdc nominal battery voltage is converted to an
intermediate voltage of 48V. This configuration is considered more efficient than the usual
12V distribution system since smaller and lighter wires can be used to carry same amount
of power. The Power Distribution Network operates off the 48V intermediate voltage, and
provides 12V output power to drive all the auxiliaries in the vehicle. The Power
Distribution Network also has the ability of detect faults from the auxiliary loads as well as
turn on and off these loads.
The Power Distribution Network is implemented with two major systems: the
Auxiliary Power System, which consists of a 360W Cuk converter with current limiting
control circuits to step-down voltage from the 48V intermediate voltage to the 12V. The
other system is the CAN Control system, it is developed using micro-controllers and standalone
CAN controllers that control and monitor the auxiliary loads in the vehicle.
The prototype Power Distribution Network is fully operational and has been tested
with eight of 12V light bulbs which are used to simulate the auxiliary loads in the vehicle.
Experimental measurements show that the prototype is able to successfully control the light
bulbs under the full load condition. This confirms that in principle the Power Distribution
Network is suitable as the power and control system for the auxiliary loads in an electric
vehicle.
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Radibratovic, Branislav. "Reactive optimization of transmission and distribution networks." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/28264.
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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.Committee Chair: Begovic, Miroslav; Committee Member: Divan, Deepakraj; Committee Member: Dorsey, John; Committee Member: Ferri, Bonnie; Committee Member: Lambert, Frank.
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Ozel, Kerem. "Losses In Electric Distribution System." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/2/12607916/index.pdf.
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The purpose of this thesis is to examine the technical losses in Electric Distribution Systems, the sources of the losses, minimum levels of the losses, ways to decrease the losses and current applications in Turkey. The wrong and weak parts of the current applications are determined and emphasized. Ways to decrease losses in Distribution Systems are advised.
The energy resources in the world are decreasing rapidly. There is a rapid growth in consumption. It is a must to use existing resources in most efficient way because there is no unlimited energy source. Losses in the electric distribution systems are one of the most important subjects because the most of the technical losses in electric systems occur in the distribution systems.
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Bachry, Andrzej. "Power quality studies in distribution systems involving spectral decomposition." Magdeburg : Univ, 2004. http://www.loc.gov/catdir/toc/fy0604/2005390390.html.
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Chan, Morgan Hing-Lap. "Communication channel characteristics and behaviour of intrabuilding power distribution circuits." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25081.
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Intrabuilding power distribution circuits offer a number of unique advantages for local area networking. To enable the selection of proper error-control codes and protocols for reliable data communication services, error pattern statistics of intrabuilding power line channels are obtained. Also, error-causing disturbances are identified and their relationships to specific types of error patterns are determined. It is found that error occurrence is highly periodic, with periodicity being a function of the power line frequency which is nominally 60Hz in North America. Furthermore, results indicate that error pattern behaviour is relatively insensitive to communication carrier frequency and modulation schemes.
Based on the measurement results, hybrid ARQ with bit-interleaving is suggested for reliable data transmission at high data rate (19,200bps). Burst error correcting codes can be used to reduce decoder cost and complexity with some sacrifices in performance. At lower data rates (1,200bps or below), effective error control can be accomplished more easily.
Finally, the attenuation characteristics of a number of typical power line channels are presented. It is found that high frequency bypass can be used to improve signal transmission between different phases of the distribution transformer.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Mbango, Fessor. "Investigation into alternative protection solutions for distribution networks." Thesis, Cape Peninsula University of Technology, 2009. http://hdl.handle.net/20.500.11838/1107.
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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009Recently, due to concerns about the liberalization of electricity supply, deregulation and global impact on the environment, securing a reliable power supply has become an important social need worldwide To ensure this need is fulfilled, detailed investigations and developments are In progress on power distribution systems protection and the monitoring of apparatus which Is part of the thesis. The main objective of a protection schemes is mainly to keep the power system stable by isolating only the affected components or the section of the electricity network in which the fault has developed while allowing the rest of the network to continue operating. It is important to note that the protection equipment does not prevent faults from occurring, but it limits the damaging effect of the fault and protects other healthy equipment. This is only achieved if the protection system of the electrical network involved complies with the requirements and purpose of the electrical protection standards. These requirements include the Operational speed, Reliability, Security and Sensitivity. In conventional substations that are still existing Within the utilities networks, a number of long cables are then used to complete the links between substation equipment in order for them to communicate (hardwired). This method is uneconomical and is being phased out completely in the near future. Over the last few years a new standard for substation automation communication has been developed Within the International Electrotechnical Commission (IEC), the IEC 61850. This standard defines the integration requirements of multi-vendor compliant relays and other lED's for multiple protection schemes as well as control and automation techniques. In this particular thesis, Distribution protection is the area of interest, particularly the application of Time and Overcurrent protection schemes. A look into different protection alternatives and the application of new technologies for Electrical Power Distribution Systems that unify protection and control units so that they can be incorporated into Intelligent Substation as opposed to the most existing (conventional substation) is analyzed. The proposed algorithm has been verified through simulations of the CPUT and Eureka three phase power distribution systems. A testing Lab is also part of this thesis and Is meant for experiments as well as simulation performance in order to gain knowledge and skills for designing and engineer substations with lEG 61850 standards equiprnents. The results indicate that the reduction of copper wiring cable has increased and the communication speed has improved and simplified.
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Ajitkumar, Rohit. "An analysis of DC distribution systems." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39590.
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The Master's Thesis research focuses on analyzing the possibilities of using Direct Current distribution systems to distribute power to end users. Considering the shift in load types in the past few decades and also a growing demand of distributed generation, DC distribution can potentially offer higher efficiencies and cost savings to utilities. The incorporation of DC distribution offers the opportunity to eliminate multiple conversion stages for devices which are powered using DC electricity. The integration of power sources such as photovoltaics and fuel cells, which produce DC power, offer further incentives to consider the use of DC systems. Using DC systems can help eliminate the conversion losses associated with rectifiers and inverters which would be part of the infrastructure if AC distribution was used. In the literature, the study of DC distribution has been limited to customized systems. The objective of this research is to analyze DC distribution when applied to systems based on standard IEEE test feeder systems. The IEEE 13 node test feeder and the IEEE 37 node test feeder will be used as the basis for the analysis. Issues such as associated costs, protection and integration of appliances will also be addressed.
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Javanshir, Marjan. "DC distribution system for data center." Thesis, Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39344952.
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Nduku, Nyaniso Prudent. "Development of methods for distribution network power quality variation monitoring." Thesis, Cape Peninsula University of Technology, 2009. http://hdl.handle.net/20.500.11838/1144.
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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009The purpose of this project is to develop methods for distribution network power quality' variations monitoring. Power quality (PO) has become a significant issue for both power suppliers and customers. There have been important changes in power system regarding to power quality requirements. "Power quality" is the combination at voltage quality and current quality. The main research problem of the project is to investigate the power quality of a distribution network by selection of proper measurement, applying and developing the existing classic and modern signal conditioning methods for power disturbance's parameters extracting and monitoring. The research objectives are: To study the standard lEC 61000-4-30 requirements. to investigate the common couplings in the distribution network. To identity the points for measurement, to develop MySQL database for the data from the measurement and to develop MATLAB software tor simulation of the network To develop methods based on Fourier transforms for estimation of the parameters of the disturbances. To develop software for the methods implementation, The influence of different loads on power quality disturbances are considered in the distribution network. Points on the network and meters according to the lEC power quality standards are investigated and applied for the CPUT Bellville campus distribution network. The implementation of the power quality monitoring for the CPUT Bellville campus helps the quality of power supply to be improved and the used power to be reduced. MATLAB programs to communicate with the database and calculate the disturbances and power quality parameters are developed.
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Wohl, Amit 1971. "Business strategy for power distribution equipment manufacturer in a deregulated electric power industry." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/84525.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2002.Includes bibliographical references (leaves 50-54).
by Amit Wohl.
S.M.
M.B.A.
23
Yu, Xuebei. "Distribution system reliability enhancement." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41091.
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Practically all everyday life tasks from economic transactions to entertainment depend on the availability of electricity. Some customers have come to expect a higher level of power quality and availability from their electric utility. Federal and state standards are now mandated for power service quality and utilities may be penalized if the number of interruptions exceeds the mandated standards. In order to meet the requirement for safety, reliability and quality of supply in distribution system, adaptive relaying and optimal network reconfiguration are proposed. By optimizing the system to be better prepared to handle a fault, the end result will be that in the event of a fault, the minimum number of customers will be affected. Thus reliability will increase.
The main function of power system protection is to detect and remove the faulted parts as fast and as selectively as possible. The problem of coordinating protective relays in electric power systems consists of selecting suitable settings such that their fundamental protective function is met under the requirements of sensitivity, selectivity, reliability, and speed. In the proposed adaptive relaying approach, weather data will be incorporated as follows. By using real-time weather information, the potential area that might be affected by the severe weather will be determined. An algorithm is proposed for adaptive optimal relay setting (relays will optimally react to a potential fault). Different types of relays (and relay functions) and fuses will be considered in this optimization problem as well as their coordination with others. The proposed optimization method is based on mixed integer programming that will provide the optimal relay settings including pickup current, time dial setting, and different relay functions and so on.
The main function of optimal network reconfiguration is to maximize the power supply using existing breakers and switches in the system. The ability to quickly and flexibly reconfigure the power system of an interconnected network of feeders is a key component of Smart Grid. New technologies are being injected into the distribution systems such as advanced metering, distribution automation, distribution generation and distributed storage. With these new technologies, the optimal network reconfiguration becomes more complicated. The proposed algorithms will be implemented and demonstrated on a realistic test system. The end result will be improved reliability. The improvements will be quantified with reliability indexes such as SAIDI.
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Kim, Jiseong. "Procedures for locating switched capacitors in electric power distribution systems /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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Khaliq, Abdul. "Preventive control for the attainment of a dynamically secure power system." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/13893.
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Angeles-Camacho, César. "Phase domain modelling and simulation of large-scale power systems with VSC-based FACTS equipment." Connect to e-thesis, 2005. http://theses.gla.ac.uk/849/.
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Thesis (Ph.D.) -- University of Glasgow, 2005.Ph.D. thesis submitted to the Department of Electronics and Electrical Engineering, University of Glasgow, 2005. Includes bibliographical references. Print version also available.
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Fallier, William F. "Analysis of system wide distortion in an integrated power system utilizing a high voltage DC bus and silicon carbide power devices." Thesis, Monterey, California. Naval Postgraduate School, 2007. http://hdl.handle.net/10945/3006.
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This research investigates the distortion on the electrical distribution system for a high voltage DC Integrated Power System (IPS). The analysis was concentrated on the power supplied to a propulsion motor driven by an inverter with simulated silicon carbide switches. Theoretically, silicon carbide switches have the advantage of being able to withstand a very large blocking voltage and carry very large forward currents. Silicon carbide switches are also very efficient due to their quick rise and fall times. Since silicon carbide switches can withstand high voltage differentials and switch faster than silicon switches, the switching effects on the electrical distribution system were investigated. The current state of silicon carbide power electronics was also investigated. This research quantifies the current and voltage distortion over various operating conditions. A system model was developed using Matlab, Simulink, and SimPowerSystems. The model consisted of a synchronous generator supplying a rectifier and inverter set driving an induction motor. This induction motor simulates the propulsion motor for a Navy ship. This model had a DC link voltage of 10 kV in order to simulate future Navy IPS systems. The current and voltage distortion were compared to MIL STD 1399 and IEEE STD 519 and 45.Contract Number: N62271-97-G-0026
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McDermott, Thomas E. "A Heuristic Nonlinear Constructive Method for Electric Power Distribution System Reconfiguration." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30447.
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The electric power distribution system usually operates a radial configuration, with tie switches between circuits to provide alternate feeds. The losses would be minimized if all switches were closed, but this is not done because it complicates the system's protection against overcurrents. Whenever a component fails, some of the switches must be operated to restore power to as many customers as possible. As loads vary with time, switch operations may reduce losses in the system. Both of these are applications for reconfiguration.
The problem is combinatorial, which precludes algorithms that guarantee a global optimum. Most existing reconfiguration algorithms fall into two categories. In the first, branch exchange, the system operates in a feasible radial configuration and the algorithm opens and closes candidate switches in pairs. In the second, loop cutting, the system is completely meshed and the algorithm opens candidate switches to reach a feasible radial configuration. Reconfiguration algorithms based on linearized transshipment, neural networks, heuristics, genetic algorithms, and simulated annealing have also been reported, but not widely used. These existing reconfiguration algorithms work with a simplified model of the power system, and they handle voltage and current constraints approximately, if at all.
The algorithm described here is a constructive method, using a full nonlinear power system model that accurately handles constraints. The system starts with all switches open and all failed components isolated. An optional network power flow provides a lower bound on the losses. Then the algorithm closes one switch at a time to minimize the increase in a merit figure, which is the real loss divided by the apparent load served. The merit figure increases with each switch closing. This principle, called discrete ascent optimal programming (DAOP), has been applied to other power system problems, including economic dispatch and phase balancing. For reconfiguration, the DAOP method's greedy nature is mitigated with a backtracking algorithm. Approximate screening formulas have also been developed for efficient use with partial load flow solutions. This method's main advantage is the accurate treatment of voltage and current constraints, including the effect of control action. One example taken from the literature shows how the DAOP-based algorithm can reach an optimal solution, while adjusting line voltage regulators to satisfy the voltage constraints.Ph. D.
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Arunachalam, Suresh. "Expansion of an existing power system - a study." Diss., Rolla, Mo. : University of Missouri--Rolla, 1989. http://scholarsmine.mst.edu/thesis/pdf/Arunachalam_09007dcc805881ce.pdf.
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Thesis (M.S.)--University of Missouri--Rolla, 1989.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed October 7, 2008) Includes bibliographical references (p. 89).
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Grisham, Jason Lynn. "A guidebook to evaluate the use of distributed generation in distribution systems." Master's thesis, Mississippi State : Mississippi State University, 2004. http://library.msstate.edu/etd/show.asp?etd=etd-03292004-220127.
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Kanduri, Venkata Ramanujam. "Distributed generation impact on fault response of a distrubution [i.e., distribution] network." Master's thesis, Mississippi State : Mississippi State University, 2004. http://library.msstate.edu/etd/show.asp?etd=etd-11122004-151757.
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Lee, Cheuk-wing. "Transmission expansion planning in a restructured electricity market." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38959410.
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Mehryoon, Shah M. "Analysis and comparison of power loss and voltage drop of 15 kV and 20 kV medium voltage levels in the north substation of the Kabul power distrubution system by CYMDIST." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1258137124.
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Adamek, Anna. "Incorporating power and assimilating nature: Electric power generation and distribution in Ottawa, 1882--1905." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26435.
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The history of electric power generation and distribution in Ottawa reflects the city's political, economic, and environmental conditions. The process of electrification of the Canadian capital was shaped by strong personalities, by municipal, provincial and federal politics, and by the city's location on the Ottawa River, an interprovincial border. The idea of electrification was introduced by municipal politicians in 1880s as a way of redefining Ottawa as a 'power capital of the Dominion' rather than as the locus of the federal bureaucracy. Yet the process was soon dominated by three powerful Liberals---Thomas Ahearn, Erskine H. Bronson and Warren Y. Soper---who gained influence among the three social groups who constituted the majority of Ottawa residents, Irish Catholics English Protestants, and Methodists. Their strong political influence in the Canadian capital allowed the three industrialists to form alliances within the provincial and federal government to permit them to build an electric empire. By 1894, the year in which they created the Ottawa Electric Company and the Ottawa Electric Railway Company, Ahearn, Bronson and Soper held a monopoly over the city's power generation and distribution. Yet as the three entrepreneurs shaped the electric market and urban development of the city, their endeavours were influenced by the politics, location, and natural resources of the Ottawa area. The same factors that fashioned a strong monopoly, also obstructed it, leading to establishment of a municipal plant in 1905 and consequently creating an electric duopoly in Ottawa.
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Wang, Yen-Ju. "Modeling, prediction and mitigation of power distribution system voltage distortion caused by nonlinear loads /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9974696.
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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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Chao, Xingyong H. "Nondivergent and optimal power flow : a unified approach." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/15499.
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McCalley, James D. "A methodology for determining the effects of non-utility generation on inter-area oscillations in electric power systems." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/16023.
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Julie, Ferdie Gavin. "Development of an IEC 61850 standard-based automation system for a distribution power network." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/1183.
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Thesis submitted in fulfillment of the requirements for the degree
Master of Technology: Electrical Engineering
in the Faculty of Engineering
at the Cape Peninsula University of TechnologyThe electric power distribution network, an essential section of the electric power system, supplies electrical power to the customer. Automating the distribution network allows for better efficiency, reliability, and level of work through the installation of distribution control systems. Presently, research and development efforts are focused in the area of communication technologies and application of the IEC 61850 protocol to make distribution automation more comprehensive, efficient and affordable. The aim of the thesis is to evaluate the relevance of the IEC61850 standard-based technology in the development and investigation of the distribution automation for a typical underground distribution network through the development of a distribution automation algorithm for fault detection, location, isolation and service restoration and the building of a lab scale test bench Distribution Automation (DA) has been around for many decades and each utility applies its developments for different reasons. Nowadays, due to the advancement in the communication technology, authentic and automatic reconfigurable power system that replies swiftly to instantaneous events is possible. Distribution automation functions do not only supersede legacy devices, but it allows the distribution network to function on another lever. The primary function of a DA system is to enable the devices on the distribution network to be operated and controlled remotely to automatically locate, isolate and reconnect supply during fault conditions. Utilities have become increasingly interested in DA due to the numerous benefits it offers. Operations, maintenance and efficiencies within substations and out on the feeders can be improved by the development of new additional capabilities of DA. Furthermore, the new standard-based technology has advanced further than a traditional Distribution Supervisory and Control Data Acquisition (DSCADA) system. These days the most important components of a DA system include Intelligent Electronic Devices (IEDs). IEDs have evolved through the years and execute various protection related actions, monitoring and control functions and are very promising for improving the operation of the DA systems. The thesis has developed an algorithm for automatic fault detection, location, isolation and system supply restoration using the functions of the IEC61850 standard-based technology. A lab scale system that would meet existing and future requirements for the control and automation of a typical underground distribution system is designed and constructed. The requirement for the lab scale distribution system is to have the ability to clear faults through reliable and fast protection operation, isolate faulted section/s, on the network and restore power to the unaffected parts of the network through automation control operation functions of the IEC61850 standard. Various tests and simulations have been done on the lab scale test bench to prove that the objective of the thesis is achieved. Keywords: IEC61850 Standard, Distribution automation, Distribution automation system, IEDs, Lab scale test bench, Protection, Algorithm for automatic control
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Wang, Zhuding. "Distribution system planning a set of new formulations and hybrid algorithms /." online access from Digital Dissertation Consortium access full-text, 2000. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?9994047.
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Jia, Ke. "Impedance based fault location in power distribution systems." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/28518/.
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This thesis presents an investigation into impedance based fault location methods which directly use the fault transient as an excitation source to provide fast and accurate fault locations in small distribution systems such as the modem marine and aircraft power systems which have Integrated Power System (IPS) configuration. Fast and accurate fault location on un-exposed power distribution lines is of vital importance to expedite service restoration and improving the reliability of the power system. Two fault location algorithms are developed: the single-ended method and the double-ended method. The singled-ended algorithm which captures current and voltage waveforms from one end of the distribution cable estimates the fault locations using an iteration calculation. The double-ended method has a simple algorithm and is robust to different fault situations but requires additional data measured from the remote end of the cable. Both simulation and experimental tests have been done and the results are good enough to validate that the developed methods can locate fault positions using a 12ms window and otter an accuracy of within 1m in the proposed distribution system. The advantages and disadvantages of the proposed fault location methods are investigated under different fault situations. The possibility of employing the two methods in protection of faults in a marine power system is demonstrated. Due to the special characteristics of the marine power system, an active method which simply involves adding an IGBT switch is proposed for the earth fault protection.
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Alvehag, Karin. "Risk-based methods for reliability investments in electric power distribution systems." Doctoral thesis, KTH, Elektriska energisystem, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-33815.
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Society relies more and more on a continuous supply of electricity. However, while underinvestments in reliability lead to an unacceptable number of power interruptions, overinvestments result in too high costs for society. To give incentives for a socioeconomically optimal level of reliability, quality regulations have been adopted in many European countries. These quality regulations imply new financial risks for the distribution system operator (DSO) since poor reliability can reduce the allowed revenue for the DSO and compensation may have to be paid to affected customers.This thesis develops a method for evaluating the incentives for reliability investments implied by different quality regulation designs. The method can be used to investigate whether socioeconomically beneficial projects are also beneficial for a profit-maximizing DSO subject to a particular quality regulation design. To investigate which reinvestment projects are preferable for society and a DSO, risk-based methods are developed. With these methods, the probability of power interruptions and the consequences of these can be simulated. The consequences of interruptions for the DSO will to a large extent depend on the quality regulation. The consequences for the customers, and hence also society, will depend on factors such as the interruption duration and time of occurrence. The proposed risk-based methods consider extreme outage events in the risk assessments by incorporating the impact of severe weather, estimating the full probability distribution of the total reliability cost, and formulating a risk-averse strategy. Results from case studies performed show that quality regulation design has a significant impact on reinvestment project profitability for a DSO. In order to adequately capture the financial risk that the DSO is exposed to, detailed risk-based methods, such as the ones developed in this thesis, are needed. Furthermore, when making investment decisions, a risk-averse strategy may clarify the benefits or drawbacks of a project that are hard to discover by looking only at the expected net present value.QC 20110530
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Østrem, Trond. "Reliable electric power conversion for connecting renewables to the distribution network." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2178.
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When connecting distributed power generation systems to the utility grid, a power converter is normally placed between the main grid and the local micro-grid, at the point of common coupling. In order to synchronize the converter to the utility grid voltages, a synchronizing circuit is needed. A common way of doing this, is to use a phase-locked loop (PLL). This circuit estimates a voltage reference angle which is fed to the control system of the power converter. One of the simplest PLL designs is based on the grid voltage zero crossings. The drawback of this method is that no information about the grid voltage conditions is available in the interval between the zero crossing. The design has been implemented and successfully tested on a Field Programmable Gate Array (FPGA) circuit connected to a power converter. A more advanced way of designing a PLL is by using voltage vector control. The method is more complex and time consuming. On the other hand, information about the grid voltage condition is always available. The design fails to run properly if the grid voltages are unbalanced or distorted. In order to improve the performance, a multi-variable filter tuned at nominal grid frequency may be added. This solution has been implemented on an FPGA circuit and successfully tested. The multi-variable filter will cause an angle displacement if the grid frequency deviates from its nominal value. The author proposes a method called Adaptive Signal Cancellation (ASC), in order to make the PLL frequency independent. The method is based on a method called Delayed Signal Cancellation (DSC) where the grid voltages are inputted and symmetric voltage components are outputted. Instead of delaying signals, the ASC is phase shifting signals, obtaining approximately the same performance. In addition to providing the control circuit with an estimated voltage reference angle, the circuit also outputs signals determining grid voltage conditions: voltage level, symmetry and frequency. These signals can be used in an overhead control structure taking care of power management and protection.
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Kuntz, Paul A. "Optimal reliability centered vegetation maintenance scheduling in electric power distribution systems /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/5969.
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Moberg, Elias. "The value of flexibility in a future electric power distribution system." Thesis, Uppsala universitet, Industriell teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-447539.
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The size and composition of the Swedish electricity generation are changing. This, in combination with new legal requirements from regulatory entities including the EU Directive 2019/944, creates several challenges for the design of the future system. Among other things, the directive suggests that flexibility solutions are to be integrated into grids to increase the degree of utilization and avoid congestions, when socio-economically profitable. This thesis evaluates what this could mean in a Swedish context, in combination with providing a basic understanding of the contradictions that can arise between a desired efficient grid use in an energy system that goes towards more distributed and intermittent energy generation sources. The work is carried out in collaboration with Vattenfall Eldistribution AB, focusing on the geographical area of Uppsala and Stockholm, the Swedish region hit hardest by local congestions. The work assumes that the economic value of a flexibility solution is at most equivalent to the cost of a conventional new construction aimed at capacity strengthening, or the Value of Lost Load (VoLL). The report’s most important deliverable is a model based on this view. The model is used to evaluate the economic value of flexibility per kWh, in three regional grid construction projects within the mentioned region. The results show that there is a great potential for using flexibility resources to increase utilization in grids and also to optimize the costs that society pays for this infrastructure by such methods. However, the work concludes that the usage of flexible technologies primarily is to adapt electric consumption with intermittent energy generation, rather than being used to solve local grid capacity shortages.
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Park, Ju-chirl. "Modeling and simulation of selected distributed generation sources and their assessment." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=1104.
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Thesis (M.S.)--West Virginia University, 1999.Title from document title page. Document formatted into pages; contains v, 99 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 88-91).
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Whitcomb, Bryan D. "Design and implementation of a high-power resonant DC-DC converter module for a reduced-scale prototype integrated power system." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA430967.
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Thesis (Electrical Engineer)--Naval Postgraduate School, September 2001.Thesis Advisor(s): Robert W. Ashton, John G. Ciezki, Todd R. Weatherford. Includes bibliographical references (p. 175-177). Also available online.
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Kleinberg, Michael R. Miu Karen Nan. "Distributed multi-phase distribution power flow : modeling, solution algorithm, and simulation results /." Philadelphia, Pa. : Drexel University, 2007. http://hdl.handle.net/1860/1307.
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Tsai, Men-Shen. "Intelligent systems for distribution operational planning and alarm processing in power systems /." Thesis, Connect to this title online; UW restricted, 1993. http://hdl.handle.net/1773/6106.
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Slavickas, Rimas Anthony. "Trade-off decisions in distribution utility mangement /." *McMaster only, 1998.
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