Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 112-113). Also available via the Internet.

Thesis (M.Sc.)--City University of Hong Kong, 2004. / At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.

Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains x, 165 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 163-165).

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 120-121). Also available via the Internet.

Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Julian, Alexander L. Second Reader: Crisiti, Roberto. "December 2009." Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Pulsed power, charger, buck converter, field programmable gate array (FPGA), lithium-ion batteries. Includes bibliographical references (p. 77-79). Also available in print.

This work develops a methodology to facilitate the optimum design of spacecraft power processing systems. Emphasis is placed on the battery charge and discharge systems. A comparison of several battery charge and discharge topologies is presented. Characteristics which effect the overall system performance are addressed including size, weight, efficiency, dynamic performance, electromagnetic interference, and reliability. A detailed comparison, using nonlinear design optimization techniques, is performed for three candidate topologies for application to the NASA Earth Observing System (EOS) satellite battery discharger. Experimental verification is provided. A novel zero-voltage-switching (ZVS) bidirectional converter topology is presented. A bidirectional battery charger / discharger has several advantages, including a potentially substantial system weight savings. However, it is shown that most of the advantages can not be realized unless zero-voltage-switching is incorporated. The design of a novel ZVS, multi-module, multi-phase, bidirectional converter with application to the NASA EOS satellite battery charger / discharger system is presented. The system not only yields high efficiency and light weight, but also possesses superior dynamic characteristics when compared to either a conventional bidirectional converter or separate charge and discharge converters. Design considerations for system control of the NASA EOS satellite are presented. A methodology is presented to insure system stability with an unknown complex load. / Ph. D.

The design, analysis, and testing of a multi-module, multi-phase (MMMP) battery charger for the NASA Earth Observing System (EOS) is presented. The MMMP converter is comprised of four independent buck converters switched 90° out of phase. The MMMP charger is compared to a single module battery charger, and shown to provide significant performance improvements. The power stage is designed for maximum efficiency and minimum weight. The control loops (Charge Regulation and Bus Voltage Regulation) designs are presented and the small-signal models are verified with experimental results. The charger testing is facilitated by the use of the Space Platform Power System Hardware Testbed. The testbed utilizes battery and solar array simulators which allow for realistic battery charger testing. / Master of Science

A vehicular battery must consist of a large number of cells to provide the necessary energy and power. Management only at the level of the battery pack causes out-of-investigation cells and lack of cell equalization ability. Therefore, in the smart module concept, cells are first grouped into modules, which are then connected to the battery pack. Each module is an independent unit with a controller to investigate and control cells. Based on this concept, the work in this thesis redistributes tasks among module controllers and a central controller, applies a self-power design to enhance module independence, and selects the newly developed automotive ICs and sensors. Finally, a prototype of the BMS has been developed and successfully applied in a series of HEVs. / Cell equalization is a crucial technique to balance the cells inside a battery pack, with the ability to maximize pack capacity and protect cells from damage. For the bi-directional Cuk equalizing circuit, we propose a SoC based, instead of voltage based, fuzzy controller to intelligently determine the equalizing current, with the aim of reducing equalizing duration, enhancing equalizing efficiency, and protecting cells. The inputs to the controller are specially designed as the difference in SoC, the average SoC, and the total internal resistance. Because of the lack of theoretical analysis on equalizing current in the electrochemistry field, we utilize a fuzzy controller to incorporate the experience and knowledge of experts. Simulations and experiments verify its availability and efficacy. Especially for a LiFePO4 battery, a large SoC difference may lead to only a small difference in voltage and cause the failure of a traditional voltage based equalizer. The SoC based method successfully avoids this problem and obtains good performance in equalizing LiFePO4 cells. / Fast charge is intended to charge a battery as fast as possible, without any damage and with high energy efficiency, thus helping to reduce vehicle out-of-service time and promote the commercialization of EVs. Battery safety and charging efficiency are partially reflected by the increase in temperature during the charging process. Therefore, the aims of this thesis were to accelerate charging speed and reduce the temperature increase. We introduce a model predictive control framework to control the charging process. An RC model and the modified enhanced self-correcting model are employed to predict the future SoC in simulations and experiments respectively. A single-node lumped-parameter thermal model and a neural network trained by real experimental data are also applied respectively. In addition, a genetic algorithm is applied to optimize the charging current under multiple objectives and constraints. Simulation and experimental results strongly demonstrate that the Pareto front of the proposed algorithm dominates that of the popular constant current constant voltage charge method. / State of charge (SoC) is a battery state indicating its residual capacity. It is the fundamental state of the battery and is the basis for other battery operations. However, SoC is not a directly measurable state and has to be obtained by estimation techniques. Aiming to enhance the anti-noise ability of SoC estimation in a real vehicle environment, we propose a SoC estimation framework consisting of an adaptive nonlinear diffusion filter to reduce the noise of current measurement, a self-learning mechanism to remove its zero-drift, an open loop coulomb counting estimator and a model based closed loop filter to estimate SoC, and a data fusion unit to reach the final estimation result. In a simulation study, the closed loop filter is implemented based on an RC model and Hinfinity filter. In experiments and application, we modify the enhanced self-correcting model to model a type of LiFePO4 battery and apply an extended Kalman filter to estimate SoC. The framework has been demonstrated to improve accuracy and anti-noise ability, and achieves the technique upgrading goal recently published by the Chinese government. / The automotive industry has experienced a significant boom in recent years, accelerating the problems of energy shortage and environmental disruption around the world. To solve the two problems, electric vehicles (EVs), including battery electric vehicles (BEV), hybrid electric vehicles (HEV), and fuel-cell electric vehicles (FEV), have been proposed and studied in recent years. Despite the efforts devoted to the development of EVs by both the scientific research and industrial communities, there are still many obstacles hindering the mass commercialization of EVs. Among these obstacles, the battery system, the new energy storage component in EVs, is one of the most important yet most difficult parts of EV design, and the battery management system (BMS) is recognized as the single most important technical issue in the successful commercialization of EVs. / Yan Jingyu. / Adviser: Xu Yangsheng. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 166-182). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 121-123). Also available via the Internet.

A contract was awarded to the Virginia Power Electronics Center to compare two battery discharger topologies for use on the Earth Observing System. The following report is the result of the optimal design, build and test of Voltage-Fed, Push-Pull Autotransformer battery discharger topology. The main thrust of this document is to achieve an optimal efficiency. The list of available parts is restricted to only those that are approved. Derating guidelines restrict the choice of power stage semiconductors in a manner that degrades efficiency so efficiency gains are sought by optimization of the power stage magnetics. A second goal of the design is to achieve optimal small and large signal performance. / Master of Science