Dissertations / Theses: 'Applications Of Electric Power'

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Bonavoglia, Marco <1987&gt. "Power Converters and Electric Drives for Smart Grid Applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6778/.

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The present dissertation aims to explore, theoretically and experimentally, the problems and the potential advantages of different types of power converters for “Smart Grid” applications, with particular emphasis on multi-level architectures, which are attracting a rising interest even for industrial requests. The models of the main multilevel architectures (Diode-Clamped and Cascaded) are shown. The best suited modulation strategies to function as a network interface are identified. In particular, the close correlation between PWM (Pulse Width Modulation) approach and SVM (Space Vector Modulation) approach is highlighted. An innovative multilevel topology called MMC (Modular Multilevel Converter) is investigated, and the single-phase, three-phase and "back to back" configurations are analyzed. Specific control techniques that can manage, in an appropriate way, the charge level of the numerous capacitors and handle the power flow in a flexible way are defined and experimentally validated. Another converter that is attracting interest in “Power Conditioning Systems” field is the “Matrix Converter”. Even in this architecture, the output voltage is multilevel. It offers an high quality input current, a bidirectional power flow and has the possibility to control the input power factor (i.e. possibility to participate to active and reactive power regulations). The implemented control system, that allows fast data acquisition for diagnostic purposes, is described and experimentally verified.

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Khan, Atif Zaman. "Eigenvalue sensitivites and their applications to power system voltage stability." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/13911.

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Mousavi, Takami Kourosh. "Process Control and Simulation of Ferromagnetic Strip in the Power Transformers and Electrical Machines Applications : Electric power systems." Doctoral thesis, Västerås : School of Sustainable Development of Sociaty and Technology, Mälardalen University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-6648.

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

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

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Cheng, Yong. "Power electronics controller prototyping tool for power system applications." Master's thesis, Mississippi State : Mississippi State University, 2006. http://sun.library.msstate.edu/ETD-db/ETD-browse/browse.

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Wang, Chengwei. "Synchronisation in complex networks with applications to power grids." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=232252.

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In this thesis, we present several novel theoretical results in complex networks, most of which benefit from extensions of existing methods of analysis in electrical engineering. These results not only contribute to a better characterisation of the topology and structure of complex networks, but also provide a new way to study complex systems by modelling them as a flow network to determine how nodes nonlocally interact as a function of the adjacent physical laws. We also contribute towards a better understanding of how frequency synchronisation (FS) in coupled phase oscillator networks comes about by revealing the fundamental mechanisms and determinant conditions for nodes to become FS. Moreover, we design a scheme to control explosive synchronisation. Equipped with the theoretical knowledge obtained from the study of phase oscillator networks, we reveal the mechanism behind the onset of FS in realistic models of power grids and the causes behind frequency collapse. Furthermore, we put forward advanced control techniques and novel prediction methods to prevent blackouts from happening in those models. These results might help engineers to construct a stable, economic and efficient smart power grid in the near future. The breakthroughs in this thesis build up a bridge which, on the one hand, promotes the progress of the research in the fields of complex networks and synchronization by borrowing methods from electrical engineering and extending them to the treatment of complex networks, and on the other hand, aids engineers to efficiently solve some specific problems in smart grids based on the knowledge of approaches coming from the area of complex systems. Therefore, this thesis bridges the gap between engineering and physics by identifying, explaining and extending interdisciplinary approaches from these two disciplines to better understand models and networks considered within these fields.

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Ebrahimpour, Mohammad Reza. "An analytical study of the power flow equations with applications to systems with multiple close solutions." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/15746.

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

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Sotomayor, Martínez Rodrigo. "System theoretic process analysis of electric power steering for automotive applications." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/105318.

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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, Engineering Systems Division, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 101-103).
The automotive industry is constantly challenged with meeting and exceeding customer expectations while reducing time to market of new products in order to remain competitive. Providing new features and functionality into vehicles for customer satisfaction is becoming more challenging and driving design complexity to a higher level. Although traditional methods of Product Development Failure Mode identification such as FMEA (Failure Mode and Effect Analysis) or FTA (Fault Three Analysis) have been used to analyze failures in automotive systems, there are limitations when it comes to design errors, flawed requirements, human factors implications, and component interaction accidents in which all components operated as required but the system behavior was not as expected. In order to determine if there is room for improvement in current automotive product development process, this thesis applies Dr. Nancy Leveson's Systems-Theoretic Process Analysis (STPA) technique to compare and contrast with a Failure Modes and Effects Analysis (FMEA) approach as used in the automotive industry through a case study. A formal method of comparing results is proposed. This study found limitations with FMEA in terms of identifying unsafe interactions between systems, anticipating human error and other behaviors dependent on human interaction, identifying engineering design flaws, and producing requirements. STPA was able to find causes that had a direct relationship with those found in FMEA while also finding a portion of causes related to a higher level of abstraction of those in FMEA. STPA also found a subset of causes that FMEA was not able to find, which relate mainly to engineering design flaws and system interaction.
by Rodrigo Sotomayor Martínez.
S.M. in Engineering and Management

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Tsang, Tony Ka Leong. "Low power weak current processing for weak biomedical applications /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20TSANG.

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Nunnally, Clay. "Magnetoresistance in semiconductor-metal hybrids for power applications." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5614.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2008.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on June 11, 2009) Vita. Includes bibliographical references.

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Rector, R. Blake. "Generalized Differential Calculus and Applications to Optimization." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3627.

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This thesis contains contributions in three areas: the theory of generalized calculus, numerical algorithms for operations research, and applications of optimization to problems in modern electric power systems. A geometric approach is used to advance the theory and tools used for studying generalized notions of derivatives for nonsmooth functions. These advances specifically pertain to methods for calculating subdifferentials and to expanding our understanding of a certain notion of derivative of set-valued maps, called the coderivative, in infinite dimensions. A strong understanding of the subdifferential is essential for numerical optimization algorithms, which are developed and applied to nonsmooth problems in operations research, including non-convex problems. Finally, an optimization framework is applied to solve a problem in electric power systems involving a smart solar inverter and battery storage system providing energy and ancillary services to the grid.

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Helbig, Achim, and Christoph Boes. "Electric Hydrostatic Actuation - modular building blocks for industrial applications." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200007.

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Electro Hydrostatic Actuators (EHA) are emerging as a viable option for industrial machine builders as the design combines the best of both electro-mechanical and electro-hydraulic technologies. The EHA is a highly integrated, compact alternative to traditional hydraulic solutions. Automation engineers moving toward electro-mechanical actuation in pursuit of energy efficiency and environmental cleanliness, will find an EHA an attractive option for high force density actuators. This paper will address the factors to consider when assessing an industrial machine’s application suitability for this latest innovation in actuation. It describes principal base circuits, a concept for EHA building blocks and a realized pilot application as well as challenges on actuator and components level.

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S, Van As M. T. "Design of a GPS based time stamping and scheduling system for power system applications." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53352.

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Thesis (MScEng)--University of Stellenbosch, 2003.
ENGLISH ABSTRACT: This thesis describes the development of a GPS Based Time Stamping and Scheduling System for power system applications. These applications include Wide Area Measurements (WAMs) of electrical power system quantities and high-voltage transmission line fault location. The developed system employs a microcontrolIer and a GPS receiver to synchronise an onboard microsecond-accurate clock to a global time standard. The system is therefore able to provide an accurate GPS-synchronised time stamp of a received trigger signal for use in highvoltage transmission line fault location. The system is also able to generate a trigger signal at a pre-programmed time for initiation of data acquisition runs on electrical power systems. The system was constructed and tested in a laboratory environment. Although the system is designed to operate in stand-alone mode, a host computer software program was also developed for system control and data downloading. The software program was used to time stamp a number of trigger signals and data was downloaded to a host computer. Trigger signals were also generated at predefined times. The acquired data was validated and presented. In conclusion, the low system cost, relative to existing commercial systems, accuracy and programmability of the developed system makes it suitable for a wide variety of time-critical data acquisition applications.
AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die ontwikkeling van 'n GPS gebaseerde tyd stempel en skedulerings sisteem met die oog op kragstelsel toepassings. Ingesluit by hierdie toepassings is wye area metings op elektriese kragstelsels, asook foutopsporing op hoogspanning transmissielyne. Die ontwikkelde sisteem gebruik 'n mikrobeheerder en 'n GPS ontvanger om 'n aanboord mikrosekonde-akkurate horlosie te sinkroniseer met 'n internasionale tyd standaard. Dus kan die ontwikkelde sisteem 'n akkurate GPS gesinkroniseerde tyd stempel aan 'n snellersein heg. Hierdie tyd stempel kan gebruik word in hoogspanning transmissielyn foutopsporing. Die sisteem kan ook 'n snellersein genereer op 'n vooraf geprogrammeerde tyd. Hierdie snellersein kan gebruik word om belangrike data van elektriese kragstelsels te versamel, deur gebruik te maak van bestaande dataversamelingstelsels. Die sisteem was ontwerp en getoets in laboratorium toestande. Alhoewel die stelselontwerp is om alleenstaande te funksioneer, is 'n beheer rekenaar gebruik om, met die hulp van ontwikkelde sagteware, die sisteem te beheer en data af te laai. 'n Tyd stempel is aan 'n aantal snellerseine geheg en hierdie data is afgelaai na 'n beheer rekenaar. Die sisteem is ook geprogrammeer om 'n aantal snellerseine te genereer op vooraf gedefinieerde tye. Die data wat uit hierdie toetse versamel is, is bespreek. In vergelyking met bestaande kommersiële stelsels is die ontwikkelde stelsel se lae koste, akkuraatheid en programmeerbaarheid eienskappe wat die stelsel geskik maak vir 'n wye verskeidenheid van tyd-kritieke dataversameling toepassings.

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Gradzki, Pawel Miroslaw. "Core loss characterization and design optimization of high-frequency power ferrite devices in power electronics applications." Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-165934/.

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Azad, Ahmed N. "Energy Management of Dynamic Wireless Power Transfer Systems for Electric Vehicle Applications." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7643.

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Wireless power transfer is a method of transferring electric power from a transmitter to a receiver without requiring any physical connection between the two. Dynamic Wireless Power Transfer (DWPT) entails having the transmitters buried under the roadway and the receiver unit being installed on the Electric Vehicle (EV). In this method, EVs are charged while driving over the transmitters as they receive bursts of electric energy at the time of significant alignment between transmitters and receivers. Compared to the stationary charging method which involves parking the EV for long hours for a full charge, the dynamic charging method (i.e., DWPT) offers convenience as the vehicle gets charged while driving. It also facilitates extended driving range of EVs. Despite offering these advantages, DWPT causes a few significant issues. DWPT charging results in a transient power profile both at grid side and EV side, which not only hampers grid-side regulation but also affects EV-battery longevity. To address these two issues, both grid-side and EV-side energy management are needed to be employed to protect the grid and the vehicle from sudden exposure to harmful power transients. In this dissertation, the grid-side and EV-side energy management methods have been investigated. Firstly, a detection system to safely detect the vehicle on charging lane is proposed. This detection system is used to facilitate safe and efficient operation of DWPT chargers on EV roadways. Secondly, A novel DWPT system is proposed, which reduces the grid-side power transients with minimal additional hardware requirements. Finally, an EV-side energy management system is proposed which reduces the exposure of EV batteries to pulsating DPWT-power, thereby helping batteries to last longer.

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

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

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Chung, Jae Hak. "Applications of digital signal processing to electric power quality and wireless communications /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.

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Raich, Raviv. "Nonlinear system identification and analysis with applications to power amplifier modeling and power amplifier predistortion." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-04072004-130800/unrestricted/raich%5Fraviv%5F200405%5Fphd.pdf.

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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2004.
Xiaoming Huo, Committee Member ; J. Stevenson Kenney, Committee Member ; Douglas Williams, Committee Member ; Erik Verriest, Committee Member ; G. Tong Zhou, Committee Chair. Vita. Includes bibliographical references (leaves 170-179).

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Moghaddami, Masood. "Design Optimization of Inductive Power Transfer Systems for Contactless Electric Vehicle Charging Applications." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3853.

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Contactless Electric Vehicle (EV) charging based on magnetic resonant induction is an emerging technology that can revolutionize the future of the EV industry and transportation systems by enabling an automated and convenient charging process. However, in order to make this technology an acceptable alternative for conventional plug-in charging systems it needs to be optimized for different design measures. Specifically, the efficiency of an inductive EV charging system is of a great importance and should be comparable to the efficiency of conventional plug-in EV chargers. The aim of this study is to develop solutions that contribute to the design enhancement of inductive EV charging systems. Specifically, generalized physics-based design optimization methods that address the trade-off problem between several key objectives including efficiency, power density, misalignment tolerance, and cost efficiency considering critical constraints are developed. Using the developed design methodology, a 3.7kW inductive charging system with square magnetic structures is investigated as a case study and a prototype is built to validate the optimization results. The developed prototype achieves 93.65% efficiency (DC-to-DC) and a power density of 1.65kW/dm3. Also, self-tuning power transfer control methods with resonance frequency tracking capability and bidirectional power transfer control are presented. The proposed control methods enhance the efficiency of power converters and reduce the Electromagnetic Interference (EMI) by enabling soft-switching operations. Several simplified digital controllers are developed and experimentally implemented. The controllers are implemented without the use of DSP/FPGA solutions. Experimental tests show that of the developed simplified controllers can effectively regulate the power transfer around the desired value. Moreover, the experiments show that compared to conventional converters, the developed converters can achieve 4% higher efficiency at low power levels. Moreover, enhanced matrix converter topologies that can achieve bidirectional power transfer and high efficiency with a reduced number of switching elements are introduced. The self-tuning controllers are utilized to design and develop control schemes for bidirectional power transfer regulation. The simulation analyses and experimental results show that the developed matrix converters can effectively establish bidirectional power transfer at the desired power levels with soft-switching operations and resonance frequency tracking capability. Specifically, a direct three-phase AC-AC matrix converter with a reduced number of switches (only seven) is developed and built. It is shown that the developed converters can achieve efficiencies as high as 98.54% at high power levels and outperform conventional two-stage converters.

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Jooste, Charl Roelof. "Development of a generic digital controller for power electronic applications." Thesis, Cape Peninsula University of Technology, 2011. http://hdl.handle.net/20.500.11838/2210.

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Thesis (MTech (Electrical Engineering)))--Cape Peninsula University of Technology, 2011.
This thesis presents an investigation into the generic tools, hardware and firmware, involved in power electronic converter control and feedback. The aim was to determine the optimal controller architecture through research of existing controllers. As soon as the architecture was established, design of the controller commenced. Explanations for the various components selected were provided. The design considerations when designing a printed circuit board (PCB) with mixed signals was also presented. The theory behind the control of a multicell converter as well the practical implementation of the control scheme in firmware was presented.

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Sun, Haibin. "Integrated Modeling of Electric Power System Operations and Electricity Market Risks with Applications." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14103.

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Through integrated modeling of power system operations and market risks, this thesis addresses a variety of important issues on market signals modeling, generation capacity scheduling, and electricity forward trading. The first part of the thesis addresses a central problem of transmission investment which is to model market signals for transmission adequacy. The proposed system simulation framework, combined with the stochastic price model, provides a powerful tool for capturing the characteristics of market prices dynamics and evaluating transmission investment. We advocate the use of an AC power flow formulations instead since it allocates transmission losses correctly and reveals the economic incentives of voltage requirements. By incorporating reliability constraints in the market dispatch, the resulting market prices yield incentives for market participants to invest in additional transmission capacity. The second part of the thesis presents a co-optimization modeling framework that incorporates market participation and market price uncertainties into the capacity allocation decision-making problem through a stochastic programming formulation. Optimal scenario-dependent generation scheduling strategies are obtained. The third part of the thesis is devoted to analyzing the risk premium present in the electricity day-ahead forward price over the real-time spot price. This study establishes a quantitative model for incorporating transmission congestion into the analysis of electricity day-ahead forward risk premium. Evidences from empirical studies confirm the significant statistical relationship between the day-ahead forward risk premium and the shadow price premiums on transmission flowgates.

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Ding, Lei. "Digital predistortion of power amplifiers for wireless applications." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-04022004-020955/unrestricted/ding%5Flei%5F200405%5Fphd.pdf.

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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2004.
J. Stevenson Kenney, Committee Member ; G. Tong Zhou, Committee Chair ; W. Marshall Leach, Committee Member ; Ye (Geoffrey) Li, Committee Member ; Jianmin Qu, Committee Member. Includes bibliographical references (leaves 100-103).

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Kalitjuka, Tatjana. "Control of Voltage Source Converters for Power System Applications." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14370.

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The research work is aimed on the investigation of possible modeling and control schemes for the dc-link of VSC, with the purpose of identifying the impact of such modeling and control on the dynamics of the conversion system. A system consisting of back-to-back converters with equivalent grid interconnection and source representation is designed in the software PSCAD/EMTDC using a detailed switching model of the inverter and rectifier components. The control technique based on the well-established concept of vector control is implemented. The main task of the master thesis is oriented towards the achievement of more reliable dc-link dynamics with smaller required capacitance. The control algorithm is based on balancing the power between inverter and rectifier through the dc-link with the minimum dc voltage variations. Dc-link voltage regulation is achieved by implementing a control based on the energy stored in the dc-link capacitor. Alignment to a dq synchronous reference frame orientation with PI regulators is used in the control philosophy for decoupling purposes.

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Sözer, Esin Bengisu Kirkici Hulya. "Gaseous discharges and their applications as high power plasma switches." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Electrical_and_Computer_Engineering/Thesis/Sozer_Esin_45.pdf.

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Prabhala, Venkata Anand Kishore. "Control and applications of double input DC-DC power electronic converters." Diss., Rolla, Mo. : Missouri University of Science and Technology, 2010. http://scholarsmine.mst.edu/thesis/pdf/Prabhala_09007dcc807bbcfe.pdf.

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Thesis (M.S.)--Missouri University of Science and Technology, 2010.
Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed June 29, 2010) Includes bibliographical references (p. 95-100).

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Loza, Emmanuel. "CASCADED HIGH VOLTAGE CONVERTER WITH VARIABLE CONTROL FOR PULSED ELECTRIC FIELD APPLICATIONS." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/807.

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Living a sustainable lifestyle while facing increasing population and decreasing natural resources has become one of humanity’s largest challenges. Locating fossil fuels is becoming more difficult while the demand for them to power our societies is ever increasing. Instead of finding more efficient methods of extracting fossil fuels, developing technologies that create renewable substitutes for fossil fuels is now the strategy. Algae biofuel matches fossil fuel performance while also meeting the criteria for renewable energy. The focus now shifts to finding methods for commercially producing algae biofuel. Therefore, the objective of this thesis is to develop a system that provides the flexibility in finding the optimum operating conditions for lysing algae. Lysing is the process of disrupting the cell membrane in order to isolate the cellular components necessary to produce biofuel. The proposed system consists of cascaded power converters that provide a pulse output voltage in order to create a pulsed electric field (PEF) to lyse algae. The proposed system is unique from any known PEF systems because it provides the ability to independently adjust peak voltage, pulse width and frequency of the output voltage. This in turn provides great flexibility in determining optimum pulse voltage at various operating conditions for lysing algae. The system was tested on its ability to control the required variables while maintaining independence from the other variables. The new network was also designed and tested on how well it regulated the specific output waveform under the effects of different load currents as well as variations in the input voltage.

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Wei, Ping, and 魏萍. "A comprehensive approach to transmission pricing and its applications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31243733.

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Barber, David Edward. "Applications of phasor measurements to the real-time monitoring of a power system." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-12162009-020322/.

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Dancy, Abram P. (Abram Paul). "Power supplies for ultra low power applications." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10069.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.
Includes bibliographical references (p. 101-103).
by Abram P. Dancy.
M.Eng.

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Balachandran, Ajith. "Novel power electronic device structures for power conditioning applications." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/9574/.

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The work presented in this thesis contains an investigation into the methods by which the semiconductor device performance can be improved with an aim to reduce the overall losses in the power conversion system. The types of devices discussed and evaluated in this thesis include Silicon MOSFETs, IGBT, CIGBT and GaN HEMT devices. The performance improvement methods suggested in literature usually involve a trade-off of device characteristics with one another. Therefore an investigation into new device technologies and structures is deemed necessary such that the performance trade-off can be avoided or be improved.

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Kim, Junhyung. "Analysis of Direct-Soldered Power Module / Heat Sink Thermal Interface for Electric Vehicle Applications." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/32071.

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Reducing the thermal impedance between power module and heat sink is important for high-power density, low-cost inverter applications. Mounting a power module by directly soldering it onto a heat sink can significantly reduce the thermal impedance at the module / heat sink interface, as compared to the conventional method of bolting the two together with a thermal grease or some other interface materials in between. However, a soldered interface typically contains a large number of voids, which results in local hot spots. This thesis describes approaches taken to reduce voids in the solder layer through surface treatment, solder paste selection, and adjustment in solder-reflow conditions. A 15MHz scanning acoustic microscope (SAM), a non-destructive inspection tool, was used to determine the void content at the module / heat sink interface. The experimental results show that a significant reduction in thermal resistance can be achieved by reducing the void content at the soldered module / heat sink interface. Moreover, a comparison of the thermal resistances in cases using the worst soldering, which contains the largest voided area, ThermstrateTM and thermal grease are presented. Thermal performances of the modules are studied by simulation with Flotherm.
Master of Science

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Dehghan, Nelo. "High resolution electric field probes with applications in high efficiency RF power amplifier design." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/73139/.

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The evolution of high power transistors has ultimately increased the complexity of their design, interaction and incorporation within microwave frequency power amplifiers. The requirement for high efficiency and high linearity for a wide band frequency by the consumer has put pressure on designers. Due to unexpected and unpredictable failures, device characterisation of the transistor in operational conditions is a highly valuable advantage. The proposed work will describe a non-intrusive, ultra-miniaturised, high resolution electric field probe system; with the capability of measuring relative voltage and waveforms distribution of complex active devices within their operating conditions. The design, construction and evolution of the probing system will be described displaying a resolution of better than 100μm, with a flat frequency response of up to 8GHz. Due to the miniaturised size and the flexibility in positioning, the probe has the ability to measure on-chip, at the device plane, across the device periphery. Results will show direct observation of device plane voltages in high power RFPAs, where the device can exhibit variation in the voltage distribution across the periphery. Such variation will be a function of the internal behaviour and not evident in the output characteristics of the device. This work will also describe a novel method for absolute calibration of the probing system which can be implemented with every movement of the measurement plane. Therefore presenting a successful and calibrated EFP system capable of device characterisation and diagnostics.

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Troullinos, George. "Estimating order reduction for dynamic systems with applications to power system equivalents." Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/13449.

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Fessler, Christopher Michael Nunnally W. C. "Improved contact design for the SiC photo-switch used in high power applications." Diss., Columbia, Mo. : University of Missouri--Columbia, 2007. http://hdl.handle.net/10355/5080.

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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed September 10, 2009). Thesis advisor: William Nunnally. Includes bibliographical references.

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Deniz, Mustafa. "Investigation Of Multilevel Inverters For D-statcom Applications." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12611447/index.pdf.

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The most important advantages of Multilevel Inverters are the absence of a coupling transformer for medium voltage applications and low harmonic current content. In this way, relocatable and economical STATCOM systems can be realized. Complex control algorithms and the isolation problems of measurement devices and power supplies are the main challenging parts of this type of application. In this study, the design, realization, and the performance of a Voltage Source Type Cascaded Multilevel Converter Based STATCOM will be investigated in terms of digital computation, control hardware and the semiconductors devices commercially available in the market. This research work is fully supported by the Public Research Grant Committee (KAMAG) of TUBiTAK within the scope of National Power Quality Project of Turkey with the project No: 105G129.

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D'Ambrosio, Marco, and Marco Medaglia. "Vertical Axis Wind Turbines: History, Technology and Applications." Thesis, Halmstad University, Halmstad University, School of Business and Engineering (SET), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-4986.

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In this Master Thesis a review of different type of vertical axis wind turbines (VAWT) and a preliminary investigation of a new kind of VAWT are presented.

After an introduction about the historical background of wind power, the report deals with a more accurate analysis of the main type of VAWT, showing their characteristics and their operations. The aerodynamics of the wind turbines and a review of different type on generators that can be used to connect the wind mill to the electricity grid are reported as well.

Several statistics are also presented, in order to explain how the importance of the wind energy has grown up during the last decades and also to show that this development of the market of wind power creates new opportunity also for VAWT, that are less used than the horizontal axis wind turbine (HAWT).

In the end of 2009 a new kind of vertical axis wind turbine, a giromill 3 blades type, has been built in Falkenberg, by the Swedish company VerticalWind. The tower of this wind turbine is made by wood, in order to get a cheaper and more environment friendly structure, and a direct driven synchronous multipole with permanent magnents generator is located at its bottom. This 200 kW VAWT represents the intermediate step between the 12 kW prototype, built in collaboration with the Uppsala University, and the common Swedish commercial size of 2 MW, which is the goal of the company.

A preliminary investigation of the characteristics of this VAWT has been done, focusing in particular on the value of the frequency of resonance of the tower, an important value that must be never reached during the operative phase in order to avoid serious damage to all the structure, and on the power curve, used to evaluate the coefficient of power (Cp) of the turbine. The results of this investigation and the steps followed to get them are reported. Moreover a energy production analysis of the turbine has been done using WindPro, as well as a comparison with and older type on commercial VAWT.

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Liu, Chen. "Real-time simulation of power electronic system for electrical transportation applications." Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCA019.

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Le développement du système électronique de puissance dans le transport électrique est poursuivi sous la forme de convertisseurs de puissance à haut rendement impliquant une topologie complexe.Bien que l'analyse et le contrôle d'un tel système soient souvent une tâche difficile en raison de l'environnement haute tension et haut courant, la simulation hardware-in-the-loop (HILs) offre un moyen sûr et rapide d'évaluer la stratégie de contrôle en simulant l'environnement externe du contrôleur dans le système embarqué.Au cours du processus, il y a deux exigences que nous devons relever dans le cadre de temps réel (i) Le processus de calcul doit être terminé avant que l'impulsion de déclenchement suivante de l'horloge en temps réel n'arrive; (ii) La latence dans le simulateur est assez petite pour être ignorée. Les périodes d'échantillonnage et de simulation dans les simulateurs basés sur CPU sont plus de 1 microseconde, il est difficile de prendre en compte l'ensemble des événements des commutateurs dans les systèmes d'entraînement modernes.En revanche, les FPGA (Field Programmable Gate Arrays) fournissent non seulement une vitesse d'échantillonnage rapide mais aussi une alternative viable pour accélérer le simulateur en temps réel. Cependant, la mise en œuvre d’un système électronique de puissance complexe dans les FPGA est l'une des limitations. Ainsi, dans cette thése, nous ferons des recherches sur la simulation en temps réel à base de FPGA avec la tentative de résoudre le problème en résolvant les questions suivantes,1.Comment pourrions-nous partitionner le système électronique de puissance et l'implémenter dans FPGA?2.Comment pouvons-nous tirer parti des fonctionnalités FPGA pour accélérer le processus de résolution de circuit3.Comment pourrions-nous optimiser les performances du FPGA?4.Comment exprimer la caractéristique de commutation non linéaire du système électronique de puissance dans le FPGA?La première question concerne la caractéristique hybride à l'intérieur du système électronique de puissance. Nous avons proposé une nouvelle méthode nodale et un solveur matriciel basé sur la décomposition de Cholesky essayant de garder la topologie du circuit fixe et de traiter chaque élément de commutation et de circuit indépendamment. La deuxième question est celle de savoir comment obtenir des approximations pour toutes sortes d’Équation différentielle (ODE). Nous avons utilisé une série de solveurs ODE parallèles pour accélérer le processus de résolution. La troisième question est d'utiliser des outils de synthèse de haut niveau (HLS) pour optimiser les performances du FPGA. De tels outils sont utilisés pour développer des unités de calcul haute performance pour des applications de simulation en temps réel. Enfin, afin de rechercher l'impact de la caractéristique de commutation non linéaire sur le système électronique de puissance, nous avons proposé un modèle IGBT ultra-rapide avec un temps de calcul en nanosecondes dans le FPGA.Dans l'ensemble, les méthodes présentées contribuent au développement du simulateur en temps réel par FPGA pour le système de transport électrique de trois façons: réduire le temps de calcul des matrices, proposer un solveur ODE parallèle dans le FPGA et optimiser les performances du FPGA
The development of power electronic system in electrical transportation is being pursued in the form of high-efficiency power converters involving complex topology. Although analysis and control of such system is often a difficult task due to the high-voltage and high-current environment, the hardware-in-the-loop simulation (HILs) offers a time-saving and safe way to evaluate the control strategy by simulating the external environment of a controller in the embedded system.During the process, there are two requirements that we have to meet in the context of racing against real-time: (i) the computation process is necessary to the end before the next trigger impulse from the real-time clock arrives (ii) the latency in the simulator is small enough to ignore. The sampling and simulation period in today’s CPU-based HIL simulators can barely go under 1 us, it is hard to take into accounts the entire switch event from PWM (Pulse Width Modulation) in modern power drive systems. In contrast, Field Programmable Gate Arrays (FPGAs) provide not only an ultra-fast sampling speed but also a viable alternative for speeding up the real-time simulator. However, the implementing the complex power electronic system on FPGAs is one of the limitations in real time simulation. Thus, in this these, we will research the FPGA-based real-time simulation with the attempt to solve the following questions,1.How could we partition power electronic system and implement it in FPGA?2.How do we leverage FPGA features to accelerate circuit?3.How could we optimize the performance of FPGA?4.How do we express the nonlinear switch characteristic of power electronic system in the FPGA?The first question is about the hybrid characteristic inside the power electronic system. In the paper, we proposed a novel nodal method and a matrix solver based on Cholesky Decomposition trying to keep the circuit topology fixed and treat each switch and circuit element independently. The second question is one that how to obtain approximations for all kind of ordinary differential equations (ODEs). We utilized a series of parallel ODE solver to accelerate the solving process and deal with the stiff problem. The third question is to use high-level synthesis (HIL) tools to optimize the performance of FPGA. Such tools are employed for developing high-performance computing units, designated hereafter as hardware solvers (HS), for real-time simulation applications. At last, in order to research the impact of nonlinear switch characteristic on the power electronic system, we proposed an ultra-fast IGBT model with a calculation time in nanoseconds in the FPGA.Overall, the presented methods contribute to the development of FPGA-based real-time simulator in three ways: reducing the calculation time of matrix solving process, proposing parallel ODE solver in the FPGA and optimizing the performance of FPGA. Thus, with the FPGA solver we built, the model of power electronic system for electrical transportation can be solved within 50 nanoseconds in high accuracy

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Falk, Olson Gustaf. "Power Electronic Stages for a TFPMSM in Wave Power Applications." Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-194201.

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Direct drive wave energy conversion systems have been identified as a potentially major contributor to the world’s energy demands, forecasting shares of up to 25 % of the energy mix. Anders Hagnestål conducts research at the Royal Institute of Technology where a novel linear transverse flux permanent magnet generator is developed. This concept machine is particularly well-suited for the pertaining operating conditions in marine environments, producing large forces at low speeds with outstandingly low resistive losses. However, it exhibits severe magnetic saturation and draws unsymmetrical phase currents at nominal operation. In addition, it possesses a low power factor. All in all, this places stern requirements on the power electronic system and control algorithms. The aim of this thesis has been to design a functioning power conditioning system that connects the machine to the electric grid. For this purpose, a three-phase two-level voltage source converter is proposed to be back-to-back connected with two-level single-phase voltage source converters (active rectifiers) interfacing each and every machine phase. It is shown that the intermediate DC link can be maintained at a constant voltage with restricted ripple while feeding power at unity power factor to the grid by appropriately sizing the DC capacitor and adopting a feedback linearization control scheme. The phase currents can be controlled effectively by means of a cascaded gain-scheduled PID controller. By including a low-pass filter the iron losses in the machine may be suppressed even at lower switching frequencies. A constrained cost optimization indicates that the converter consequently can reach 99.1 % efficiency. Finally, with this thesis as a background, it is suggested that the thermal stresses on the selected semiconductor modules and the iron losses of the machine are evaluated to further improve the design. If higher efficiency of the active rectifiers is strived for, more complex converter topologies could be considered.
Direktdrivna vågenergiomvandlingssystem har utpekats som en potentiellt starkt bidragande resurs för att tillgodose världens efterfrågan på energi med andelar på uppemot 25 % av energimixen förutspådda. Anders Hagnestål bedriver forskning och utveckling av en ny typ av linjär permanentmagnetiserad transversalflödesmaskin vid Kungliga Tekniska Högskolan. Konceptmaskinen är särskilt väl lämpad för de rådande marina förhållandena genom att kunna producera stora krafter vid låga hastigheter med utomordentligt låga resistiva förluster. Maskinen går emellertid i kraftig magnetisk mättnad och drar asymmetriska strömmar vid nominell drift. Dessutom är effektfaktorn låg i jämförelse med standardmaskiner. Alltsomallt inför detta hårda krav på det effektelektroniska systemet och kontrollalgoritmerna. Målet med detta examensarbete har varit att designa ett funktionellt effektkonditioneringssystem som sammanfogar maskinen med det angränsande elektriska nätet. För att åstadkomma detta föreslås att en tvånivås-trefasomriktare kopplas rygg-mot-rygg till tvånivås-enfasomvandlare (aktiva likriktare) som i sin tur är kopplade till varje maskinfas. Med den här konfigurationen visas det att spänningen på den mellanliggande DC-länken kan hållas konstant med begränsat rippel, alltmedan effekt tillförs nätet vid effektfaktor ett genom att dimensionera DC-kondensatorn på rätt sätt och använda en kontrollag baserad på exakt linjärisering. Maskinens fasströmmar kan kontrolleras effektivt med hjälp av en kaskadkopplad PID-regulator med schemalagda förstärkningsfaktorer. Genom att inkludera ett lågpassfilter förväntas det att järnförlusterna i maskinen kan begränsas även vid lägre switchfrekvenser. Genom att lösa ett kostnadsoptimeringsproblem visas det att den resulterande aktiva likriktaren kan uppnå en verkningsgrad på 99.1 %. Slutligen, med det här examensarbetet som grund, föreslås det att den termiska stressen på de valda halvledarkomponentsmodulerna och järnförlusterna i maskinen utvärderas för att ytterligare förbättra designen. Om högre verkningsgrad eftersträvas hos de aktiva likriktarna kan mer komplicerade omvandlartopologier övervägas.

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40

Wagner, Justin Taylor. "Evaluation of power-assist hydraulic and electric hybrids for medium- and heavy-duty vehicle applications." Thesis, Colorado State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1564530.

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Under pressure from rising fuel costs, emissions constraints, and new government regulations on medium- and heavy-duty vehicles, hybrid technologies for these classes of vehicles are becoming more prevalent. A variety of technologies have been proposed to meet these requirements including power-assist hybrid electric and hybrid hydraulic systems. Although there has been great discussion about the benefits surrounding each of the technologies individually, no direct comparisons are available on the basis of economics and fuel economy. This study focuses on comparing these power-assist technologies on these bases as well as determines the ability of these technologies to fulfill the newly adopted fuel economy regulations.

In order to accomplish this goal, three computational models of vehicle dynamics, thermal behavior and fuel economy were created and validated to simulate the conventional vehicle and hydraulic and electric hybrids. These models were simulated over the Heavy-Duty Urban Dynamometer Driving Schedule, the HTUF Class 4 Parcel Delivery Cycle, and the Orange County Bus cycle. These drive cycles were chosen on their ability to characterize the variety of operating conditions observed in medium- and heavy-duty vehicles. Using these models, cross technology comparisons were constructed comparing commercially available systems, systems with a fixed mass, and systems with a fixed incremental cost.

The results of the commercially available systems showed that the Azure Dynamics HEV provided greater fuel economy improvement than the Lightning Hybrids HHV for drive cycle kinetic intensities less than 3.19 miles^-1. Although this system showed a cost of fuel savings over the HHV, it was seen that the incremental cost of the HEV exceeded the cost of fuel savings over the HHV. The fixed mass comparison case, which compared vehicles with equal cargo carrying utility, showed similar results to that of the commercially available case. Although the increase in incremental cost for the varying HEV systems designed for the fixed mass case correlated to an improvement in fuel savings, the cost associated with the systems surpassed the savings seen. Lastly, the fixed cost case provided results which were also similar to the commercially available case. Due to the fixed system cost, it was seen that for these systems, the fuel economy benefits and associated cost showed the greatest benefits for the HEV.

This study concluded that given the evaluation, the HEV was the only power-assist hybrid technology which could fulfill the regulated fuel economy improvement of 15%. Although the HEV was the only technology which could fulfill the requirements, the HHV showed an improvement upwards of 7% greater than the HEV for the Orange County Bus Drive Cycle.

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Fritz, Wilfred Leslie Owen. "Development of a solid state distributed lighting system for rural energy efficient applications." Thesis, Cape Peninsula University of Technology, 2006. http://hdl.handle.net/20.500.11838/1157.

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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2006
The electrical supply utility, ESKOM, cannot cope with the growing demand in South Africa. This results in load shedding and power outages. This capacity can be augmented, by conducting energy audits, retrofitting government buildings, designing and installing cost-effective lighting systems, and using renewable energy sources in rural areas. Households in rural areas depend on candles and paraffin lamps to supply light at night. Solar panels as renewable energy sources are very expensive in conventional lighting systems. The problem is that a cost-effective, affordable lighting system has not yet been designed. The following four projects have been completed by the author: - Software development for a lighting design in general - Efficient high bright light emitting diode (HB-LED) lighting system - Energy audit and retrofit of the Nuwe Hoop School in Worcester - Optimization of hybrid solar-diesel system Firstly, the author wrote a program that is used in lighting designs. This illumination software is utilized for educational purposes. A manual step-by-step lighting design procedure was compiled. The JAVA object-oriented programming language was used to write the code of the design software. Real life design parameters are fed to the program, to confirm proper implementation. The software package will perform illuminance calculations to display relevant Isolux diagrams for educational purposes.

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Johnstone, Paul Trevor. "Applications of High Voltage Power Supplies in the Purification of Water." Thesis, University of Canterbury. Electrical and Computer Engineering, 2001. http://hdl.handle.net/10092/1181.

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High voltage treatment technology has been developed in this thesis and had initially shown promise in its effectiveness in reducing microorganisms found in water supplies. Initial testing found that the high voltage could destroy over 99.9% of the bacteria S. marcescens (a 3-log reduction). Cited literature on the effects of high voltage pulsed electric fields (PEFs) on various microorganisms have shown that high destruction rates of up to 9-log can be achieved. Thus by increasing the electric field strength or exposure time, or by improving the design of the electrode flow chamber, better results should be achieved using high voltage on water. However, contrary to this, upon further design improvements the 99.9% destruction threshold was rarely increased. The initial slow flow device of one litre-per-minute (1 LPM) was scaled up to flows of 10 LPM and 33 LPM. However, these faster flow devices were even less effective in the destruction of bacteria, destroying only 99% of S. marcescens (2-log reduction). No physical or technical design parameters could account for this low performance. One possible reason for these low results was in the preparation of the bacteria themselves. It was discovered that the growth stage of bacteria prepared for experiments had a large effect on the results. Bacteria harvested in the early growth stage could be nearly all destroyed by the high voltage (greater then 4-log reduction), whereas those harvested in the late stationary stage were much more resistant (less than 0.5-log reduction). Bacteria naturally occurring in water supplies will mostly be in a non-metabolising state. This implies that they will be more resistant to high voltage exposure than bacteria grown in a laboratory under standard testing procedures. Thus standard testing procedures for this device do not give accurate results. Further research into the mechanism behind the bacterial resistance is required to improve the performance of high voltage devices. A combination of different technologies may also prove effective in overcoming the resistance mechanism. These improvements are required before high voltage treatment can be properly developed and commercially exploited.

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Adamu, Tigist Atnafseged. "Electromagnetic Interference in Dwnhole Applications." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19394.

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SummaryElectromagnetic compatibility (EMC) and electromagnetic interference (EMI) are topics which have been of concern to electrical industry for many years. Excessive generation of electromagnetic noise and interference, resulting inadequate EMC, is one potential source of interaction and performance degradation which may reduce operational effectiveness of the devices. Because of this, EMC testing services and regulation imposed by governments have forced product designer to pay close attention electromagnetic interference level of their products.For improving oil and gas production recovery, from mature fields and for exploitation of deep and ultra-deep offshore reservoirs new downhole technologies are required. Electrification of downhole applications has proven to be very promising and the technologies are designed for deployment in harsh environments. This master thesis deals with the study of EMI problems for downhole drive train system especially caused by EMI phenomena. The two aspects of EMI and EMC are studied, the manner in which how EMI can generate and propagate then affect receptor or victim intentionally and unintentionally are discussed. Followed by types of EMI phenomena (voltage dip, electrostatic discharge (ESD), surge, fast transient and rapid voltage change (dv/dt)) their occurrence and adverse effects of them are studied. dv/dt, overvoltage and EMI filter types are studied and designed. Compressions are made by their performance, size, power loss and cost. To verify their performance simulation model are made for downhole drive system to filter dv/dt and overvoltage at the motor terminals.After having the theoretical base, practical pre-compliance conducted EMI measurements are made for single phase chopper and three phase inverter.The influence of EMI such as reverse recovery current of diode, stray or leakage inductance, gate drive resistance, heat sink grounding, duty cycle and switching frequency are investigated on the single phase chopper. An LfCf harmonic filter is designed and placed between the inverter and motor terminals and differential mode EMI noise is measured in the system.

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Bucossi, William Louis. "Process voltage temperature compensated on-chip CMOS active inductors for Wilkinson power dividing applications." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/bucossi/BucossiW0508.pdf.

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Few academic or industry feasibility studies have been published on the implementation of Active Inductors in a standard CMOS IC process as an alternative to the physically large and typically quite lossy spiral inductors. Development efforts at the simulation level have achieved only limited success in creating an Active Inductor topology that exhibits the quality and inductive tolerance necessary for the large-scale, high-volume production common to most IC components. This thesis focuses on manufacturing and characterizing the basic component circuitry necessary for the implementation of a lumped-element Wilkinson power divider using active inductors and develops a compensation scheme to control the parameters of merit in the active inductor across a useful process, voltage and temperature operating window. Hardware results presented reinforce the need to actively compensate the Active Inductor structure implemented in a 0.6um (AMIS C5) CMOS process. Simulation results presented show the benefits of a compensated Active Inductor incorporated into a typical RF network.

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Kelkar, Kapil S. "Silicon carbide as a photoconductive switch material for high power applications." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4469.

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Thesis (Ph. D.) University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 3, 2007) Includes bibliographical references.

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Shu, Chang. "Application of optimization methods for power system economic operation and transfer capability evaluation /." Internet access available to MUN users only, 2003. http://collections.mun.ca/u?/theses,163245.

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Das, Sauparna 1979. "Magnetic machines and power electronics for power MEMS applications." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/34465.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.
Includes bibliographical references (p. 321-323).
This thesis presents the modeling, design, and characterization of microfabricated, surface-wound, permanent-magnet (PM) generators, and their power electronics, for use in Watt-level Power MEMS applications such as a microscale gas turbine engine. The generators are three-phase, axial-flux, synchronous machines, comprising a rotor with an annular PM and ferromagnetic core, and a stator with multi-turn surface windings on a soft magnetic substrate. The fabrication of the PM generators, as well as the development of their high-speed spinning rotor test stand, was carried out by collaborators at the Georgia Institute of Technology. The machines are modeled by analytically solving 2D magneto-quasistatic Maxwell's Equations as a function of radius and then integrating the field solutions over the radial span of the machine to determine the open-circuit voltage, torque and losses in the stator core. The model provides a computationally fast method to determine power and efficiency of an axial-air-gap PM machine as a function of geometry, speed and material properties. Both passive and active power electronics have been built and tested. The passive power electronics consist of a three-phase transformer and diode bridge rectifier.
(cont.) The active power electronics consist of a switch-mode rectifier based on the boost semi-bridge topology which is used to convert the unregulated AC generator voltages to a regulated 12 V DC without the need for rotor position/speed or stator terminal current/voltage sensing. At the rotational speed of 300,000 rpm, one generator converts 16.2 W of mechanical power to electrical power. Coupled to the transformer and diode bridge rectifier, it delivers 8 W DC to a resistive load. This is the highest output power ever delivered by a microscale electric generator to date. The corresponding power and current densities of 57.8 MW/m3 and 6x 108 A/m2, respectively, are much higher than those of a macroscale electric generator. At the rotational speed of 300,000 rpm, the generator and switch-mode rectifier delivered 5.5 W DC to a resistive load at a power density three times that of the passive electronics. This Watt-scale electrical power generation demonstrates the viability of scaled PM machines and power electronics for practical Power MEMS applications.
by Sauparna Das.
Ph.D.

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Yamamoto, Kazusa. "Control of electromechanical systems, application on electric power steering systems." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAT069/document.

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De nos jours, la plupart des véhicules sont équipés de Directions Assistées Electriques (DAE). Ce type de systèmes d'aide à la conduite permet de réduire les efforts que le conducteur doit fournir pour tourner les roues. Ainsi, grâce à un moteur électrique, la DAE applique un couple additionnel en accord avec le comportement du conducteur et la dynamique du véhicule. Il est donc nécessaire de développer une commande en couple basée en particulier sur le signal provenant d'un capteur mesurant le couple agissant au niveau de la barre de torsion (correspondant à une image du couple conducteur). Ce composant est donc essentiel au fonctionnement de la DAE. Or, une défaillance de ce capteur entraine le plus souvent une coupure de l'assistance, pouvant mener à un risque d'accidents. Au regard de la sécurité fonctionnelle, un développement d'un mode de sécurité est recommandé, par de plus en plus de constructeurs automobiles. D'autre part, le marché des équipementiers automobiles reste un secteur très concurrentiel où une baisse des coûts de production est un challenge constamment recherché afin de gagner de nouvelles parts de marchés. Cet aspect de réduction du nombre de capteurs et d'analyse de la dynamique du véhicule s'inscrit donc dans le prolongement de la stratégie de sécurité. Cette thèse, menée au sein de JTEKT Europe, aborde ces divers enjeux. Après une présentation des différents systèmes de directions assistés électriques, des modèles sont présentés pour être utilisés lors de la conception de lois de commande et d'estimateurs. Ensuite deux méthodes d'estimation du couple conducteur sujet aux perturbations de la route et aux bruits de mesures sont proposées : la première est un observateur proportionnel intégral (PI) à synthèse mixte $H_infty/H_2$, et la seconde une approche par filtrage $H_infty$. Puis plusieurs stratégies de commande sont proposées suivant deux cas de figures distincts, soit en utilisant un observateur PI qui estime les états du système et le couple conducteur (LQR, commande LPV par retour d'état), soit en faisant abstraction d'estimateur de couple conducteur (commande $H_infty$ par retour de sortie dynamique). Ce dernier aspect présente l'avantage de nécessiter moins de mesures que le précédent. Ces approches ont été validées en simulation et mises en œuvre sur un véhicule prototype où des résultats prometteurs ont été obtenus
Nowadays, modern vehicles are equipped with more and more driving assistance systems, among them Electric Power Steering (EPS) helps the driver to turn the wheels. Indeed, EPS provides through an electric motor, an additional torque according to the driver's behaviour and the vehicle's dynamics to reduce the amount of effort required to the driver. Therefore, a torque control is developed based on the torque sensor signal which measures in practice the torsion bar torque (corresponding to an image of the driver torque). Consequently, this component is essential to the functioning of EPS systems.Indeed, a torque sensor failure usually leads to shut-off the assistance which may increase the risk of accident. Regarding functional safety, a back-up mode is recommended and required by more and more car manufacturers. On the other hand, a major challenge for automotive suppliers is to reduce cost production in order to meet growing markets demands and manage in the competitive sector. This issue considering a reduction of sensors' numbers and analysis of vehicle's dynamics is therefore an extension of applying the safety strategy. This thesis, carried out within JTEKT Europe, addresses these various issues.After introducing an overview of the different EPS systems, some models used for the design of controllers and estimators are presented. Then, two methods to estimate the driver torque subject to road disturbances and noise measurements are proposed: the first is a proportional integral observer (PI) with mixed synthesis $H_infty / H_2 $, whereas the second is an $ H_infty $ filtering approach. Then, several control strategies are proposed according to two different cases, either by using a PI observer which estimates the system states and the driver torque (LQR, LPV feedback control) or by not taking into account the driver torque estimation ($ H_infty $dynamic output feedback control). This latter approach has the advantage to require less measurements than the previous one. These approaches have been validated in simulation and implemented on a prototype vehicle where promising results have been obtained

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49

Rossouw, Claire Angela. "The accelerated life cycle testing and modelling of Li-ion cells used in electric vehicle applications." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1012709.

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Li-ion batteries have become one of the chosen energy storage devices that are used in applications such as power tools, cellular phones and electric vehicles (EV). With the demand for portable high energy density devices, the rechargeable Li-ion battery has become one of the more viable energy storage systems for large scale commercial EVs because of their higher energy density to weight or volume ratio when compared to other current commercial battery energy storage systems. Various safety procedures for the use of Li-ion batteries in both consumer and EV applications have been developed by the international associations. The test procedures studied in this dissertation demonstrated the importance of determining the true capacity of a cell at various discharge rates. For this, the well known Peukert test was demonstrated. The study also showed that cells with different battery geometries and chemistries would demonstrate different thermal heating during discharge and slightly different Ragone results if different test methods were used as reported in the literature. Accelerated ageing tests were done on different cells at different Depth-of-Discharge (DoD) regions. The different DoD regions were determined according to expected stresses the electrode material in a cell would experience when discharged to specific DoD that follows the discharge voltage profile. Electrochemical Impedance Spectroscopy (EIS) was used to measure various electrochemical changes within these cells. The EIS results showed that certain observed modelled parameters would change similarly to the ageing of the cell as it aged due to the accelerated testing. EIS was also done on cells at different State-of-Charge (SoC) and temperatures. The results showed that EIS can be used as an effective technique to observe changes within a Li-ion cell as the SoC or temperature changed. For automotive vehicles that are powered by a fuel cell or battery, a supercapacitor can be coupled to a battery in order to increase and optimize the energy and power densities of the drive systems. A test procedure in the literature that evaluated the use of capacitors with Pb-acid batteries was applied to Li-ion type cells in order to quantify the increased power due to the use of a supercapacitor with a Li-ion cell. Both a cylindrical LiCoO2 cell and a VRLA Pb-acid cell showed some additional charge acceptance and delivery when connected to the supercapacitors. A LiMn2O4 pouch cell showed significant charge acceptance and delivery when connected to supercapacitors. The amount of additional charge acceptance and delivery of the different combinations could be explained by EIS, in particular, the resistance and capacitance of the cell in comparison to the combination of the cell and supercapacitor. A large capacity LiCoO2 cell showed high charge acceptance and delivery without connection with a supercapacitor. The study proved that EIS can be used to model the changes within cells under the different conditions and using different test procedures.

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Selli, Giuseppe. "BGA footprints modeling and physics based via models validation for power and signal integrity applications." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.umr.edu/thesis/pdf/Selli_09007dcc8040f1b6.pdf.

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Thesis (Ph. D.)--University of Missouri--Rolla, 2007.
Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed December 7, 2007). Includes bibliographical references.

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Dissertations / Theses on the topic 'Applications Of Electric Power'

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