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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.
1

Improving charging system availability in a blast furnace

Hendricks, Osrick Morne 08 June 2012 (has links)
M.Ing. / Steel products can be produced by either following the blast furnace with oxygen steel making route or the electric arc steel making route. The blast furnace with oxygen route requires liquid iron to produce steel and the electric arc route requires scrap metal as a major input. This in essence implies that for the blast furnace route if no liquid iron is produced, no steel products will be produced and similarly so for the electric arc route. ArcelorMittal Vanderbijlpark Works produces its liquid iron from two furnaces namely blast furnace C and blast furnace D. However the reliability of these furnaces is in question as their daily operations are plagued with random failures of equipment and machinery. The main consequence of these failures is the unavailability of the furnaces to produce liquid iron. This is undesirable from a business perspective due to the inherent production losses, loss of potential earnings as well as the high costs incurred to restore the furnaces back into operation.This research dissertation will focus on the operation of these blast furnaces. The fundamental success criteria for this research document will be to identify opportunities to improve the reliable operation of these furnaces. The scope of the work will however be limited to blast furnace C and particularly at improving its charging system’s availability. The availability of the charging system can be improved by knowing what type of failures to expect and how to mitigate their effects. A starting point would then be to examine past failure data. Thus data from 2008 has been collected and analyzed making use of statistical methods, design analysis methods and research methodologies. The results suggest that the availability of the system has a direct correlation between its reliability and maintainability. The results obtained were then subjected to a risk analysis to identify measures that could be employed to improve the charging system’s availability.
2

Proposal of Wireless Charging Method and Architecture to Increase Range in Electric Vehicles

Nezamuddin, Omar 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Electric vehicles (EVs) face a major issue before becoming the norm of society, that is, their lack of range when it comes to long trips. Fast charging stations are a good step forward to help make it simpler for EVs, but it is still not as convenient when compared to vehicles with an internal combustion engine (ICE). Plenty of infrastructure changes have been proposed in the literature attempting to tackle this issue, but they typically tend to be either an expensive solution or a difficult practical implementation. This dissertation presents two solutions to help increase the range of EVs: a novel wireless charging method and a multi-motor architecture for EVs. The first proposed solution involves the ability for EVs to charge while en route from another vehicle, which will be referred to from here on as vehicle-to-vehicle recharging (VVR). The aim of this system is to bring an innovative way for EVs to charge their battery without getting off route on a highway. The electric vehicle can request such a service from a designated charger vehicle on demand and receive electric power wirelessly while en route. The vehicles that provide energy (charger vehicles) through wireless power transfer (WPT) only need to be semi-autonomous in order to ``engage'' or ``disengage'' during a trip. Also, a novel method for wireless power transfer will be presented, where the emitter (TX) or receiver (RX) pads can change angles to improve the efficiency of power transmission. This type of WPT system would be suitable for the VVR system presented in this dissertation, along with other applications. The second solution presented here will be an architecture for EVs with three or more different electric motors to help prolong the state of charge (SOC) of the battery. The key here is to use motors with different high efficiency regions. The proposed control algorithm optimizes the use of the motors on-board to keep them running in their most efficient regions. With this architecture, the powertrain would see a combined efficiency map that incorporates the best operating points of the motors. Therefore, the proposed architecture will allow the EV to operate with a higher range for a given battery capacity. The state-of-the-art is divided into four subsections relevant to the proposed solutions and where most of the innovations to reduce the burden of charging EVs can be found: (1) infrastructure changes, (2) device level innovations, (3) autonomous vehicles, and (4) electric vehicle architectures. The infrastructure changes highlight some of the proposed systems that aim to help EVs become a convenient solution to the public. Device level innovations covers some of the literature on technology that addresses EVs in terms of WPT. The autonomous vehicle subsection covers the importance of such technology in terms of safety and reliability, that could be implemented on the VVR system. Finally, the EV architectures covers the current typologies used in EVs. Furthermore, modeling, analysis, and simulation is presented to validate the feasibility of the proposed VVR system, the WPT system, and the multi-motor architecture for EVs.
3

Bezobslužná nabíjecí stanice pro elektromobily / Self-service station for charging of electric automobiles

Kubizňák, Jan January 2010 (has links)
The subject of this diploma thesis is a creation of SW for the self-service charging station of ELNICO Ltd. company. The work consists of two main parts. The first part contains an overview of general charging stations for electro cars at current market. After this the prototype of the ELNICO system is described. It's main components and the control system realized by the development kit DK-LM3S9B96 are characterized here. The real-time operating system FreeRTOS, that is used by the kit, is also specified. The second part of the document deals with the SW design and realization. The thesis describes the structure and the main modules of the program. The functionality is then demonstrated by photos of running application.
4

Status of The Technology for Electrical Road Focusing on Wireless Charging : International Outlook

Parameswaran Thampi, Padma Kumar, Thodukulam Poulose, Thomas Paul January 2020 (has links)
Abstract The transportation sector has a vital role in today’s society and accounts for 20 % of our global total energy consumption. It is also one of the most greenhouse gas emission intensive sectors as almost 95 % of its energy originates from petroleum-based fuels. Due to the possible harmful nature of greenhouse gases, there is a need for a transition to more sustainable transportation alternatives. A possible alternative to the conventional petroleum-based road transportation is, implementation of Electric Road Systems (ERS) in combination with electric vehicles (Evs). There are currently three proven ERS technologies, namely, conductive power transfer through overhead lines, conductive power transfer from rails in the road and inductive power transfer through the road. The wireless charging or inductive charging electric vehicles (EV) are a type of EVs with a battery which is charged from a charging infrastructure and using the wireless power transfer technology. The wireless charging EVs are classified as stationary or dynamic charging EVs. The stationary charging EVs charge wirelessly when they are parked as well as dynamic charging EVs can charge while they are in motion. Number of studies have reported that, one of the main benefits of dynamic charging is, it allows smaller as well as lighter batteries to be used due to the frequent charging using in the charging infrastructure embedded under roads. The purpose of this thesis is to understand the recent developments of technologies in wireless charging system globally and find out the best effective method which can use for fuelling all Electric vehicles. The findings show that not all countries are viable for ERS from an economic standpoint, however, a large number of countries in the world do have good prospects for ERS implementation. Findings further indicated that small and developed countries are best suited for ERS implementation. From a technological and Business perspective, the wireless charging system in road was found to be the most attractive ERS technology followed by overhead conductive road ERS technologies.
5

Bi-directional Charging System Design for a set of Li-ion Batteries Located at Angstrom Laboratory Campus of Uppsala University

Mohammed, Mosab January 2023 (has links)
In this study, onboard chargers for EVs are investigated and a design of bi-directional onboard chargers is proposed and simulated. The goal of the charger is to be built in the future to be used in the test setup at Uppsala University. The charger consists of two stages: a power factor correction (PFC) converter, which converts AC voltages and currents from the grid side to DC while maintaining a unity power factor, and a bi-directional buck-boost converter, which regulates the charging and discharging current of the battery. The model was built using MATLAB/SIMULINK and the d-q synchronous reference frame was utilized to implement the current controller of the PFC converter, while the bi-directional buck-boost current controller was constructed using DC pulse width modulation. The Proportional and Integral gains were tuned using the MATLAB single input and single output tool (sisotool). The converter's topologies, structure, and corresponding mathematical model were investigated, and the charger was simulated and tested for charging and discharging modes. The battery voltage, current, and state of charge were monitored during all modes of operation to evaluate the performance of the buck-boost controller, and the functionality of the PFC controller and filter was tested by measuring the currents and voltages on the AC side. The charging and discharging efficiencies were mapped under various battery voltages and current sets to determine the performance of the charger under different operating conditions. The charger demonstrated excellent performance during charging and discharging modes and recommendations for future work to improve the efficiency and performance of bi-directional charging systems were provided.
6

Induktives Ladesystem für den Einsatz in autonomen Verleihstationen

Vogt, Johannes Paul, Kertzscher, Jana 28 February 2020 (has links)
Der vorliegende Beitrag beschreibt das Konzept eines induktiven Ladesystems für autonome Verleihstationen. Unter Beachtung der Betriebsanforderungen wird im ersten Teil eine zweckmäßige Spezifikation des Ladesystems erarbeitet. Der zweite Teil beschreibt die Modellierung des Resonanzübertragers, welcher technisch als Prototyp realisiert wurde. Dazu erfolgt die analytische Berechnung der Parameter und Vergleich mit den experimentell bestimmten Parametern am Prototypen. / This article describes the concept of an inductive charging system for autonomous sharing stations. In accordance with the operational requirements, a suitable specification of the charging system is developed in the first part of this paper. The second part describes the modelling of the resonant transmitter, which was technically realized as a prototype. For this purpose, the analytical calculation of the parameters and their comparison with the experimentally determined parameters on the presented prototype are carried out.
7

Optimization of Inductive Wireless Charging Systems for Electric Vehicles: Minimizing Magnetic Losses and Limiting Electromagnetic Field Emissions

Mohammad, Mostak 29 August 2019 (has links)
No description available.
8

Využití solární energie pro elektromobilitu / Use of solar energy for electromobility

Harant, Miroslav January 2019 (has links)
The thesis deals with the use of solar energy for electromobility. First, the potential of electromobility on the current market is theoretically discussed. This issue includes mainly the producers of electrically powered vehicles, the issue of electric energy storage and the real applications of fast charging and photovoltaic charging stations. In the next part, electric cars are analyzed, which use solar energy for their function and their efficiency is compared with the effiency of combustion engines. The main part of this thesis is the design of photovoltaic charging station for electric vehicles. The final part deals with the economic evaluation of the proposed charging station.
9

Využití solární energie pro elektromobilitu / Use of solar energy for electromobility

Harant, Miroslav January 2020 (has links)
The thesis deals with the use of solar energy for electromobility. First, the potential of electromobility on the current market is theoretically discussed. This issue includes mainly the producers of electrically powered vehicles, the issue of electric energy storage and the real applications of fast charging and photovoltaic charging stations. The second part of the diploma thesis deals with the measurement of electric car consumption and the evaluation of measurement results. In the next part, electric cars are analyzed, which use solar energy for their function and their efficiency is compared with the effiency of combustion engines. The main part of this thesis is the design of photovoltaic charging station for electric vehicles. The final part deals with the economic evaluation of the proposed charging station.
10

Experimental Investigations and Theoretical/Empirical Analyses of Forced-Convective Boiling of Confined Impinging Jets and Flows through Annuli and Channels

V.S. Devahdhanush (13119831) 21 July 2022 (has links)
<p>This study comprises experimental investigations and theoretical/empirical analyses of three forced-convective (pumped) boiling schemes: (i) confined round single jet and jet array impingement boiling, and flow boiling through conventional-sized (ii) concentric circular annuli and (iii) rectangular channels. These schemes could be utilized in the thermal management of various applications including high-heat-flux electronic devices, power devices, electric vehicle charging cables, avionics, future space vehicles, etc.</p>

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