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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.
21

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.
22

Effective and Adaptive Energy Restoration in WRSNs by a Mobile Robot

Aloqaily, Osama Ismail 04 November 2021 (has links)
The use of a mobile charger (MC) is a popular method to restore energy in wireless rechargeable sensor networks(WRSN), whose effectiveness depends critically on the recharging strategy employed by the MC. In this thesis, we propose a novel on-line recharging mechanism strategy, called Continuous Local Learning (CLL), which predicts the current energy level of the sensor nodes and dynamically updates the schedule to visit the nodes before their batteries get depleted. The strategy is based on simple computations done by the MC with little memory requirements, and the communication is strictly local (between the MC and neighbouring nodes). In spite of its simplicity, this strategy was experimentally shown to be highly effective in keeping the network perpetually operating, ensuring that the number of sensing holes (i.e., non-operational sensors due to battery depletion) and their duration are very small at any time, and achieving immortality (i.e., no node ever becoming nonoperational) under many settings even in large networks. We also studied the flexibility of CLL under a variety of network parameters, showing its applicability in various contexts. We particularly focused on network size, data rate, sensors’ battery-capacity, and speed of the MC, and studied their impact on operational size and disconnection time under a wide range of values. The experiments indicate the fact that the effectiveness of CLL holds under all considered settings. We then compared the proposed solution with the popular class of static strategies since they share with CLL the features of simplicity, strict local communication and small memory and computational requirements. Experimental results showed that CLL outperforms these strategies in effectiveness. Not only is the number of sensors that are operational at any time higher under CLL, but the average duration of a sensing hole is also significantly lower. Finally, we studied the adaptability of CLL to a network’s sudden changes, in particular changes in data rate, which we call spikes. We studied the impact of spikes parameters on the performance of CLL. Experimental results showed that CLL is capable of reacting and adapting to these sudden changes with only a slight increase in non-operational size and disconnection time.
23

Rychlonabíječka pro trakční akumulátor elektromobilu "Peugeot106 electric" / Fast charger for the traction accumulator of the electric vehicle "Peugeot 106 electric"

Langer, Radim January 2009 (has links)
This diploma thesis refers to Terminal project 1 and Terminal project 2 from former years of my studies. This work engages in design and construction of high-current charger for the electric vehicle Peugeot 106. Firstly, there is given an account of electric vehicle. There is made reference to its parameters and the way of its battery charging part. Secondly, the work deals with design concept of high-current charger and with its theoretical lay-out. Respectively, this work substantially touches on issues of chosen power, control, regulative and protective circuits of high-current charger. Thirdly, practical assembly procedure of high-current charger is detailed. Dimensioning of particular elements is described in this work. Photos and schemes of given apparatus are shown. Last but not least, results of measurement on assembled high-current charger are stated in this work.
24

Testování a nabíjení akumulátorových článků / Testing and charging of accumulator cells

Sršeň, Jan January 2009 (has links)
Direction of the master's thesis is design and construct electronic device for testing available accumulators. Than there are in detail subscribe some metods of charging cells and their right usage to select type of cells. Also eventually problems that can become if the choice is false. Next part contains description of principles as several type accumulator works and their loading characteristic witch are important know for choose the best testing way. The most important knowledge is detection of stop point charging when accumulators are charged and following charging can be dangerous. Because there are more methods to detect this point so in thesis are overwrite. The most important part is design of tester. That is mapped to more segments witch communicating together. Controller part of intelligent tester contains ATmega128 microcontroller so there is present a passage of program code. Last section of master's thesis describe a physical consruction and explain division for smaller parts and hole process of tester function.
25

Spínané zdroje ve vozidlech elektrické trakce / Switching source in electric tractions vehicle

Škunda, Michal January 2010 (has links)
The first part of this work describes the design and implementation of switch-mode power supply for control circuits for 12/2x24V 4.5A fuel cells. The introduction picks the issue of power sources in electromobiles and final design and implementation of switching power suply. The next part deals with the issues of fast-charger and generators for power transistors. It describes the structure of DC converter and control and protectin circuits of quick-charger. In the end this work describes selected driver circuits and charge tests on fast-charger as evidenced by measurements.
26

Automatický nabíječ akumulátorů pro zdravotnické přístroje / Automatic battery charger for medical equipment

Talanda, Oldřich January 2010 (has links)
The goal of this thesis is describe properties accumulators used in medical industry and proposal automatic baterry charger for medical equipment. The first part of the master’s thesis describes the most commonly used types of electrochemical accumulator systems used in the medical industry. Further listed are the criteria for the identification of the accumulator charge status. The second part of the master’s thesis defines demands on automatic baterry charger and proposal factual network solution.
27

Nabíječ akumulátorů s mikrokontrolérem. / Accumulator Charger with Microcontroller

Losenický, Roman January 2011 (has links)
My master thesis is focused on intorducing, analysing and describing the microprocessor controlled charger. The thesis is firstly describing and analysing the topic of accumulator cell charging for common technologies. Than there is detailed description of specific accumulator cell types (NiMH, NiCd and Li-ion) which is the microprocessor controled charger intend for. The next part of this thesis is showing the proposal of the charger. There is the block diagram, charger detailed schematics based on this block diagram. There is also list of the possible useful componets neccessary for charger assembling. All this is used for the final proposal of the chager itself. The main scope of this thesis is than the charger's microcontroler firmware decribed at the end of this thesis. Finaly confirmation of the charger proper proposal and assembly is the battery charging with the given basic parameters.
28

Nabíječka olověných akumulátorů / Lead Acid Battery Charger

Jeleček, Ondřej January 2013 (has links)
This diploma thesis is focused on design of lead acid baterry charger. First chapters describes the charging and discharging principes. This paper also shows basics types of lead acid batteries, their distribution depends on maintenance and part connected to the processes connected to the charging and discharging of the acumulators. Following part is focused on theoretical design of the charger with set up of parameters. Diploma thesis also contains comparsion of requested and real parameters of the charger.
29

Návrh konstrukce, řízení a elektroniky pro nestabilní balancující vozidlo / Design of construction, control and electronics for unstable balancing vehicle

Zouhar, František January 2011 (has links)
Thesis deals with design of construction, control and electronics for unstable balancing vehicle. The rst part is focused on the determination of requirements for the function and then design and manufacture of structure in line with set requirements, including 3D models and drawings. The second part is devoted to the creation of simulation models of vehicles using the Lagrange equations of the second kind and using SimMechanics. Also PID and LQR regulators are designed, including the advantages and disadvantages of each regulator for this application. The last part is focused on electronics necessary to vehicle operating. They are mainly power electronics (H-bridge, battery charger, switching supply of voltage board). There are also necessary calculations, complete PCB design and a description of the rmware for the this specifc device.
30

The process of creating an identity : Designing a product series of EV chargers

Hellström, Gustav January 2022 (has links)
The world is quickly changing and the transition away from fossil fuels is occurring at a rapid pace. The car industry has experienced a radical change in the last years replacing combustion cars with electrical ones. The infrastructure to support the new vehicles with charging facilities has not met the demand in terms of accessibility and technical performance. Neither have the chargers reached a sustainable number to support the ever-increasing number of electric cars on the road. To adapt to this need companies have started to pursue next generation chargers. This paper focused on creating the next generation of chargers with visual design, interaction, and manufacturing as the focus point. This project is a collaboration with the company Zpark to create a new visual branding for their products and improve the user experience for their user group.  The project takes a wide approach to initial research, looking at both AC and DC chargers on the market as well as the user groups' current opinions. This research was implemented to create a DC charger (fast charging unit), as the company had not yet created a product that could cover this market segment. In the design process, a visual branding was created to make Zpark a more recognizable company. Several features were distinguished that could be implemented on future products in their line-up, whilst also creating the possibility of re-branding to specific buyers. A suggested manufacturing process and material choice were made to work as a guideline to create a more sustainable product, with ecological and economic impact as factors.  Four main categories of needs for the charger were elaborated on to create a better interaction, both for users charging and owners of the chargers. These four categories were charging, payment, communication, and maintenance. All the solutions help to create a more sustainable charging solution that will aid the transition to electric with a future-proofing aspect in mind.

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