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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

DSP-Based Research on Rapid Charging Strategy of Lead-Acid Battery

Hung, Kuo-Yuan 06 July 2005 (has links)
The Lead-Acid battery has become the power source of several electron product. The major drawback is that it requires long charging time. This thesis is to design a programmable rapid charger and energy recovery scheme with DSP. Furthermore zero-voltage-switching(ZVS) capability of the adopted asymmetrical half-bridge topology enhances the power density of the charger. The energy recovery cell stores the negative pulse energy into DC bus capacitor temporarily to avoid unnecessary energy consumption in conventional schemes. This thesis is experimentally verified on 12V/7.5Ah nonspillable sealed-lead assembled batteries. According to experimental results, the charger can achieve the goal of rapid charge within 1 hour. Because of using the rapid charge algorithm, it can give different charging section depends on temperature and voltage of battery, and it can adjust the over-temperature and the over-voltage of battery to guarantee the battery be charged safely. In this thesis, a prototype module is implemented with mature protection condition. Some experiments are shown to verify the feasibility of the proposed scheme.
12

Design and Implementation of Intelligent Battery Charger and Residual Capacity Estimator for Electric Vehicle

Yang, Yung-Yi 04 July 2000 (has links)
This paper designs and implements a DSP based intelligent battery charger and residual capacity estimator for electric vehicle. This system uses the proposed new electric circuit structure and the intelligent fuzzy charge algorithm to charge batteries, and the improved coulometric measurement with accurate residual capacity estimation to estimate the residual capacity of batteries. From the experimental results, the charger can achieve the purpose of fast and uniform charge with charging time six (6) to eight (8) hours, and will not cause the damage of battery because of using the intelligent fuzzy charge algorithm can give different charging current depend on the difference of voltage, capacity and temperature of battery; the residual capacity estimator can accurate estimate the residual capacity of batteries due to calculating the increment current and considering the aging factor.
13

Management and Diagnosis of Intelligent Battery Charger and Residual Capacity Estimator for Electric Vehicle

Cheng, Fu-Kang 30 July 2001 (has links)
This paper Management and Diagnosis a DSP based intelligent battery charger and residual capacity estimator for electric vehicle. This system uses the proposed new electric circuit structure and the intelligent fuzzy charge algorithm to charge batteries, and the improved coulometric measurement with accurate residual capacity estimation to estimate the residual capacity of batteries. From the experimental results, the charger can achieve the purpose of fast and uniform charge with charging time six (6) to eight (8) hours, and will not cause the damage of battery because of using the intelligent fuzzy charge algorithm can give different charging current depend on the difference of voltage, capacity and temperature of battery; the residual capacity estimator can accurate estimate the residual capacity of batteries due to calculating the increment current and considering the aging factor.
14

Design and Implementation of Intelligent Battery Charger and Residual Capacity Estimator

Chen, Ying-Chou 09 July 2002 (has links)
This paper designs and implements a DSP based intelligent battery charger and residual capacity estimator. This system uses the proposed structure of the series circuit and battery equalizer with the intelligent fuzzy charge algorithm to charge batteries, and the improved coulometric measurement with accurate residual capacity estimation to estimate the residual capacity of batteries. Because of using the intelligent fuzzy charge algorithm can give different charging current depend on the difference of voltage, capacity and temperature of battery; And because of using the battery equalizer can adjust the voltage of battery. The charger can charge the battery safely without causing any damage. From the experimental results, the charger can achieve the purpose of fast and uniform charge with charging time six (6) to eight (8) hours, the residual capacity estimator can accurate estimate the residual capacity of batteries due to calculating the increment current and considering the aging factor.
15

Research and Development of Intelligent Power Management with DSP Control Unit

Yeh, Ja-Ming 16 July 2003 (has links)
This thesis is to design an intelligent battery charger and residual capacity estimator with DSP. This system uses the proposed structure of the series circuit and battery equalizer with the intelligent fuzzy charge algorithm to charge battery, The internal resistance measurement can accurately estimate the residual capacity of battery. Because of using the intelligent fuzzy charge algorithm, it can give different charging current depends on voltage, capacity and temperature of battery. Because of using battery equalizer, it can adjust the voltage of battery to guarantee the battery be charged safely. According to experimental results, the charger can achieve the goal of fast and uniform charge within 6 to 8 hours. On the residual capacity estimator, We measure internal resistance to accurately estimate residual capacity of battery, because internal resistance is affected by environmental temperature, battery corrosion, aging factor and output current .
16

Electric Vehicle (EV) Wireless Chargers: Design And Optimization

Ramezani, Ali January 2021 (has links)
Wireless charging of the EVs offers a convenient, reliable, and automatic charging of the autonomous vehicles without user interference. The focus of this thesis is the design and optimization of new structures for stationary EV wireless charging applications. The fundamentals of the Wireless Power Transfer (WPT) system and its main components including the magnetic couplers, transmitter and receiver power converters, and control methods are studied in depth. The requirements of the EV wireless charging application and design criteria are discussed in detail. The advantages and disadvantages of each topology are highlighted, and possible candidates for EV wireless charging applications are selected. Optimization of the resonant networks in terms of maximum efficiency and misalignment tolerance is studied. Different resonant topologies are studied in detail and their sensitivity functions are extracted. For each topology, an efficiency model is presented that includes the inverter, resonant capacitors, resonant inductor, diode-bridge, and core and conduction losses. Each topology is optimized with two different objective functions and the results are compared through the simulation and experiments. According to the optimization results, suitable topologies for the EV wireless charging application are selected. In order to increase the power density of the wireless charging system, and save ferrite material, integrated inductors into the magnetic couplers are proposed. In this structure, the DC-DC inductor is integrated into the receiver main coil and the resonant inductor is integrated into the transmitter coil. This integration introduces new challenges to the design of the resonant network and magnetic coupler due to the unwanted cross-coupling effect. To address this issue, the fully integrated magnetic structure is optimally designed to have minimum cross-coupling. Moreover, the resonant network is designed based on an optimization problem that includes the cross-coupling into the system equations to ensure maximum efficiency. The proposed fully-integrated magnetic structure is built and experimental tests are presented to validate the performance of the proposed magnetic structure and its optimization method. To reduce the implementation cost, size and weight a PCB-based magnetic coupler is proposed to replace the Litz wire in the magnetic coupler of the WPT system. Moreover, the proposed PCB-magnetic coupler increases the repeatability of the design and reduces manufacturing errors. The PCB-based magnetic coupler is studied through Finite Element Analysis (FEA) to minimize the AC resistance of the coil. Different parameters such including the number of the PCB layers, copper cross-section, and layer thickness are studied in detail to evaluate their effect on the coil resistance. Thermal analysis is performed to ensure the feasibility of the design under different loading conditions. A 3.3 kW/85 kHz wireless charging system is built and experimental tests are presented. A novel modular resonant topology for fast wireless charging is proposed. A modular structure offers reliability, scalability, and better thermal management. The proposed topology is made by multi-parallel inverter legs connected to an LCC resonant network. The outputs of the resonant networks are connected in parallel to feed the transmitter coil with a high excitation current. The proposed modular system is compared with a conventional system and it showed superior performance in different aspects. / Thesis / Doctor of Philosophy (PhD)
17

Design and Implementation of High Efficiency, High Power Density Front-End Converter for High Voltage Capacitor Charger

Kang, Yonghan 06 May 2005 (has links)
Pulse power system is widely used for medical, industrial and military applications. The operational principle of the pulse power system is that the energy from the input source is stored in the capacitor bank or superconducting inductive device through a dc-dc converter. Then, when a discharging signal exists, the stored energy is released to the load through pulse forming network (PFN) generating high peak power pulse up to gigawatts within several tens of or hundreds of microseconds. The pulse power system has been originally developed for the defense application. After the format of the voltage compression and voltage addition stages for the short-pulse high power acceleration has been established, it has been evolved to be common. Then, its application has been extended to food processing, medical equipment sterilization and wastewater treatment since many present environmental problems have been known in the early 70's or even earlier. In addition, the pulse power system is newly spotlighted due to the recent world events. The application examples are to treat anthrax-contaminated mail, and the use of accelerators to produce high power X-rays for security screening. Furthermore, the pulse power system has been applied for the tactical weapon system such as electrothermal-chemical (ETC) gun, coilgun and active armor system. Because the pulse power system applied for the tactical weapon system has the potential to be integrated in the military vehicle, a compact, lightweight pulse power system is strongly required for the future weapon system. In this thesis, a distributed power system (DPS) for the capacitor charger is introduced for the application of the active armor system. Furthermore, a design methodology is presented for the front-end converter to achieve the high efficiency as well as the high power density. Design parameters are identified and their impact on the design result is studied. the optimal operating point is determined based on the loss comparison between different operating points. In order to further improve the power density utilizing the unique operation mode i.e. pulse power operation, transformer design using amorphous-based core is provided and the design result is compared with that using ferrite-based core. A 5 kW prototype converter is built up and the experimentation is performed to verify the design. / Master of Science
18

Kabelavlastningskoncept till EV-snabbladdare / Cable relief concept for EV-fast charger

Olsson, Alexander, Andersson, Karl January 2023 (has links)
Elbilar blir mer och mer populära i samhället och bredvid traditionella bensinstationer står laddstolpar för att förse elbilar med energi. Dover Fueling Solutions (DFS) har under många år levererat bränslelösningar till kunder över hela världen. DFS är världsledande i branchen och har ett stort intresse av att vidareutveckla och undersöka innovativa lösningar på laddningsprocessen. I takt med att elbilsförsäljningen ökar, så ökar intresset för en snabb och enkel laddningsprocess. En kabel som sitter mellan en laddstolpe och en elbil väger idag cirka tre kg per meter. Då laddluckan sitter på olika ställen på olika elbilar krävs en viss räckvidd med handtaget från laddstolpen. En lång räckvidd och tung sladd gör att laddningsprocessen kan bli tung och osmidig. För att förenkla laddningsprocessen undersöks hur en kabelavlastning kan göra processen lättare. Utifrån en given kravspecifikation och med systematisk produkutvecklingsmetodik tas ett kabelupphängningskoncept fram. Konceptet ska ha en lång räckvidd från laddstolpen och en kabelavlastning samt är det önskvärt med en tilltalande design. Konceptet består av ett inelastiskt snöre som i ena änden sitter fast i en kabel och i andra änden sitter fast i en motvikt vars syfte är att avlasta kabeln när laddstolpen används i max utdraget läge. Konceptet detaljutvecklas och dimensioneras med hjälp av hållfasthetsberäkningar. Det färdiga konceptet illustreras i en 3D-CAD modell. / Electric cars are becoming more and more popular in society and next to traditional gas stations there are charging posts to supply electric cars with energy. Dover Fueling Solutions (DFS) has for many years supplied fueling solutions for customers all over the world. DFS is a world leader in the industry and has a great interest in further developing and researching innovative solutions for the charging process. As electric car sales increase, so does interest in a fast and simple charging process. A cable that runs between a charging post and the electric car weighs about three kilograms per meter. As the docking outlet is mounted in different places on different models of electric cars, a certain range is required with the handle from the charging post. A long range and heavy cord means that the charging process can be cumbersome and awkward. In order to simplify the charging process, it is being investigated how a cable weight relief can make the process easier. Based on given requirement specifications and with systematic product development methodology, a cable weight relief concept is developed. The concept must have a long reach from the charging post and a cable relief, and it is desirable with an appealing design. The concept consists of an inelastic string that is attached to a cable at one end and at the other end is attached to a counterweight whose purpose is to relieve the cable when the charging post is used in the maximum extended position. The concept is developed in detail anddimensioned using strength calculations. The finished concept is illustrated in a 3D CAD model.
19

Modeling and Simulation of a Three-phase AC-DC Converter where the Impedances of the Feeding Lines are considered

Lotfalizadeh, Behnood January 2013 (has links)
This thesis comprises modeling and simulation of an AC-DC converter (Battery charger). An AC-DC converter may cause a high frequency distortion in the electrical power network or augment the existing distortion caused by other devices connected to the network. The goal is to design a controller for suppressing this noise at a reasonable level. We hope the thesis can be considered as a step forward to solve the original problem. One needs an accurate model of the AC-DC converter, to design such a controller. This study tries to clarify the effects of theline inductance on the performance of the converter by modeling and simulating the converter during the commutation time. The idea is to model and simulate the converter for two different conditions; first in the Normal condition by neglecting the effect of line impedance, second in the Commutation condition by considering the effect of the line impedance on commutation of the diodes. One can perform a complete simulation of the converter with combining these two models. The thesis deals with AC-DC converters, Hamiltonian-port modeling, simulation and MATLAB programming using the functionality of the S-function and SIMULINK.
20

Design of a Two-Stage Level-Two Bidirectional On-Board Battery Charger for Plugin Vehicles

Wong, Noreen Nga-Yee January 2013 (has links)
Depletion of fossil fuel reserves, increasing awareness of air pollution levels and continuous rise in gasoline prices are some of the major drives that have been revolutionizing the automotive industry since the last decade. These factors combined are causing conventional automobiles with internal combustion engines (ICE) to be replaced with plugin vehicles. The on-board rechargeable battery packs in plugin vehicles can be recharged by connecting to the utility grid using a plug. The energy stored in the on-board battery packs has attractive benefits for grid support, and this promotes the idea of Vehicle-to-Grid (V2G). V2G power transactions allow energy from the on-board battery packs to be sent back to the utility grid for support in peak shaving and provide reactive power compensation. One natural consequence that arises with the introduction of V2G is a sharp increase in the need for high-performance power electronic interface between the utility grid and the battery pack. Therefore, research on bidirectional battery chargers for plugin vehicles is imperative in order to aid in the promotion of V2G. This thesis focuses on the design and development in a two-stage level-two on-board bidirectional battery charger.

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