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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

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.
2

Intelligent Infrastructures for Charging Reservation and Trip Planning of Connected Autonomous Electric Vehicles

Shaikh, Palwasha Waheed 24 September 2021 (has links)
For an environmentally sustainable future, electric vehicle (EV) adoption rates have been growing exponentially around the world. There is a pressing need for constructing smart charging infrastructures that can successfully integrate the large influx of connected and autonomous EVs (CAEVs) into the smart grids. To fulfill the aspiration of massive deployment of autonomous mobility on demand (AMoD) services, the proposed fast and secure framework will need to address the long charging times and long waiting times of static charging. It will also need to consider dynamic wireless charging as a viable solution for the CAEVs on the move. In this thesis, a novel three-layer charging system design of static and dynamic wireless charging that can operate with the existing wired charging infrastructure and standards for Intelligent Transportation System (ITS) is presented. This internet of things (IoT) application is accompanied by a proposed handshake protocol with light-weight request message frames. It employs vehicle to infrastructure (V2I) and vehicle to grid (V2G) communications for fulfilling charging requests of CAEVs with the shortest possible route to the destination. The charging requests of the CAEV users are fulfilled by dynamically distributing the request over the three different types of charging equipment. Further, the requests are serviced and billed privately and securely using two different proposed payment schemes with the encrypted virtual currency. The hardware independent system can detect misalignment of the CAEVs on the wireless charging pads and the speed issue errors in dynamic wireless charging systems as well as avoid free-riders. Additionally, the proposed dynamic wireless charging network (DWCN) design specification tool is analyzed. The suggestions made by the tool for building a DWCN can enable implementers to achieve the desired charging delivery performance at the lowest cost possible. Finally, the presented system is simulated, and this verified and validated simulator is revealed to make reservations and plan trips with minimum waiting times, travel costs, and battery consumption per vehicle trip. The system results proved 90.25% charge delivery efficiency. This system is then compared with alternative system designs to help showcase its ability to aid implementers and analysts in making design choices with the simulation.
3

Charge par induction de véhicules électriques : analyse du potentiel, limitations, nouveaux concepts / Induction charging for electrical vehicles : Potential, limits, new concepts

Hammoud, Achraf 24 November 2017 (has links)
Les progrès concernant l’autonomie des batteries ont rendu le véhicule électrique vraiment compétitif. Cependant un problème n'est pas vraiment résolu, celui du temps de charge des batteries qui reste long même avec des bornes de forte puissance. La charge par induction peut compenser en partie ce handicap grâce à une infrastructure quasi-transparente pour l'utilisateur, basée sur l'équipement des zones de stationnement.L'objectif de cette thèse est d’étudier le potentiel et les limitations de la charge par induction, éventuellement par l'introduction de nouveaux concepts, dans la gamme des puissances de plusieurs dizaines de Kilowatts et sur des distances supérieures à 10cm entre l’inducteur et l’induit. L'obtention de bons rendements et le respect de dimensions en accord avec l'intégration dans le véhicule sont des points essentiels de la démarche.Dans un premier temps, différentes topologies de compensation de l'énergie réactive, indispensable dans cette application, sont comparées et la topologie dite Série-Série (SS) est finalement retenue. De la même façon, différentes architecture d’électronique de puissance sont évaluées. L’architecture correspondant à l'utilisation d'un onduleur primaire commandé en phase shift à fréquence variable, et d'un simple pont de diode secondaire est adoptée. Elle permet de réguler le courant injecté dans les batteries tout en simplifiant l’électronique de puissance, c.à.d. sans utiliser de convertisseurs DC-DC ni au primaire, ni au secondaire.Un outil de calcul des pertes dans le fil de Litz est ensuite mis en place. Il permet d'évaluer les pertes dans les bobinages en fonction de la section du fil et du diamètre des brins, l'objectif étant de trouver la combinaison "section de cuivre/diamètre de brins" minimisant les pertes.La troisième étape consiste à mettre en place des outils de conception analytiques complétés par des simulations "éléments finis" pour concevoir les bobinages du coupleur électromagnétique ainsi que son blindage magnétique. Des montages expérimentaux à petite échelle permettent une première validation de ces outils de conception. Enfin un algorithme d’optimisation est développé.Sur la base des solutions identifiées dans la première partie, les outils de conception ont été finalement utilisés pour concevoir un démonstrateur de 22kW, capable de transférer l’énergie sur une distance de 25cm entre l’inducteur et l’induit. Ce démonstrateur a été testé avec succès à la puissance nominale. Le rendement mesuré est de 95% lorsque les bobines primaire et secondaire sont alignées. / Scientific progress in battery field related to autonomy has made electric vehicles really competitive. However, there is a problem that hasn’t been solved yet, the duration of the charge which still high, even if high power chargers are used. Inductive charging could be a solution to that problem because the infrastructure can become almost transparent for the user if it is implemented in car park areas.The aim of this PhD work is to evaluate the potential and the limitations of inductive charging, to identify eventual new concepts, in a fast charge power range (few tens of Kilowatts) and with air gaps higher than 10cm.First, different topologies of reactive energy compensation are compared and the Series-Series (SS) topology is selected. Then, in the same way, different power electronics architecture are compared. The architecture using a phase-shifted DC-AC converter to supply the primary side and a simple power bridge to supply the secondary side is adopted. This architecture allows regulating the current in the batteries without using DC-DC converters neither on the primary side nor on the secondary side.Then, a software is implemented that is able to calculate losses in Litz wire, as a function of the wire section and the strands diameter, the aim being to choose a Litz wire that minimizes the losses in the windings.The third step is the implementation of a tool dedicated to the design of the primary and secondary coils and of the magnetic shields. The tool is based on analytic equations and finite elements simulations. The design tool is validated by means of reduced scale experiments. Finally, an optimization algorithm is implemented.Considering the solutions identified in the first part, the previous design tools are finally used to design a 22kW prototype able to transfer energy through an air gap of 25cm. This prototype has been successfully tested at nominal power. An efficiency of 95% has been measured when the two coils are aligned.
4

Bezdrátová nabíjecí stanice / Wireless charging station

Pokorný, Josef January 2018 (has links)
The paper deals with possibilities of wireless charging and transmission of electric energy using inductive coils. Basic models of air coils are described using CST simulation software. The product consists of a transducer for transmitting coil, two coils with ferromagnetic shield, synchronous rectifier and battery charging circuit. Communication is provided by an 8-bit microcontroller with wireless modules and an ethernet shield for online monitoring. The aim of the thesis is to design a wireless charging station with a power transfer of 40 W with the possibility of online monitoring of the charging state.
5

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.
6

MULTI-PHYSICS MODELS TO SUPPORT THE DESIGN OF DYNAMIC WIRELESS POWER TRANSFER SYSTEMS

Anthony Frank Agostino (10035104) 29 April 2022 (has links)
<p>  </p> <p>Present barriers to electric vehicle (EV) adoption include cost and range anxiety. Dynamic wireless power transfer (DWPT) systems, which send energy from an in-road transmitter to a vehicle in motion, offer potential remedies to both issues. Specifically, they reduce the size and charging needs of the relatively expensive battery system by supplying the power required for vehicle motion and operation. Recently, Purdue researchers have been exploring the development of inductive DWPT systems for Class 8 and 9 trucks operating at highway speeds. This research has included the design of transmitter/receiver coils as well as compensation circuits and power electronics that are required to efficiently transmit 200 kW-level power across a large air gap.</p> <p>In this thesis, a focus is on the derivation of electromagnetic and thermal models that are used to support the design and validation of DWPT systems. Specifically, electromagnetic models have been derived to predict the volume and loss of ferrite-based AC inductors and film capacitor used in compensation circuits. A thermal equivalent circuit of the transmitter has been derived to predict the expected coil and pavement temperatures in DWPT systems that utilize either single- or three-phase transmitter topologies. A description of these models, along with their validation using finite element-based simulation and their use in multi-objective optimization of DWPT systems is provided.</p>
7

Trådlös laddning med en textil : Kan en broderad spole möjliggöra induktionsladdning av en mobiltelefon?

Bergmark Giesler, Linn, Abrahamsson, Anna January 2019 (has links)
The development of electronic textiles has increased significantly during the last ten years. By integrating electronic components or using conductive thread you can create textiles with different technical functions. CEVT is a innovation company within the automotive industry who have gained interest in electronic textiles. The department of innovation want to explore the possibility to integrate electronic textiles into future cars. The mission they have assigned us is a sub-goal in a larger end goal in which we will investigate whether one can develope a textile that can charge a phone wirelessly. To do this, a textile transmitter coil must be produced to enable the induction charging, which is what wireless charging really means. The method that was chosen to produce the textile transmitter coil was embroidery and the conductive thread that was used was a silver plated polyamide thread (HC12) from Sheildex. The thread had a resistance of &lt;100 Ω per meter and some difficulties arose early on, where the resistance of the embroidered coil was to high. To reduce the resistance multiple stitches were sewn together and the conductive thread was also used as a lower thread. The resistance of the final coil had an average of almost 15 Ω which was significantly higher than desired. Tests were made to measure the inductive capability of the embroidered coil. This was done by measuring the power transmission between an embroidered coil and a Samsung Galaxy s8 reciever coil. The results showed that a power transmission was enabled, which means that it works. Though the power transmission was a lot lower when compaired to a commercial transmitter coil that was tested at the same time. The project did not result in a fabric that could wirelessly charge a mobile phone. Nevertheless, the test results showed that it is possible, since a power transmission did occur between the textile coil and the coil from the Samsung. Further research and optimization of the textile coil would be required to realize the induction charging textile. Two interesting ways to go would be by using another embroidery technique called Fibre Tailored Placement (FTP) or by developing a new conductive embroidery thread, with a lower resistance. / The development of electronic textiles has increased significantly during the last ten years. By integrating electronic components or using conductive thread you can create textiles with different technical functions. CEVT is a innovation company within the automotive industry who have gained interest in electronic textiles. The department of innovation want to explore the possibility to integrate electronic textiles into future cars. The mission they have assigned us is a sub-goal in a larger end goal in which we will investigate whether one can develope a textile that can charge a phone wirelessly. To do this, a textile transmitter coil must be produced to enable the induction charging, which is what wireless charging really means.The method that was chosen to produce the textile transmitter coil was embroidery and the conductive thread that was used was a silver plated polyamide thread (HC12) from Sheildex. The thread had a resistance of &lt;100 Ω per meter and some difficulties arose early on, where the resistance of the embroidered coil was to high. To reduce the resistance multiple stitches were sewn together and the conductive thread was also used as a lower thread. The resistance of the final coil had an average of almost 15 Ω which was significantly higher than desired.Tests were made to measure the inductive capability of the embroidered coil. This was done by measuring the power transmission between an embroidered coil and a Samsung Galaxy s8 reciever coil. The results showed that a power transmission was enabled, which means that it works. Though the power transmission was a lot lower when compaired to a commercial transmitter coil that was tested at the same time.The project did not result in a fabric that could wirelessly charge a mobile phone. Nevertheless, the test results showed that it is possible, since a power transmission did occur between the textile coil and the coil from the Samsung. Further research and optimization of the textile coil would be required to realize the induction charging textile. Two interesting ways to go would be by using another embroidery technique called Fibre Tailored Placement (FTP) or by developing a new conductive embroidery thread, with a lower resistance.
8

Αποδοτικά πρωτόκολλα ασύρματης φόρτισης σε δίκτυα αισθητήρων / Efficient protocols for wireless charging in sensor networks

Ράπτης, Θεοφάνης 16 May 2014 (has links)
Οι τελευταίες εξελίξεις στα πεδία της ασύρματης μετάδοσης ενέργειας και των υλικών μπαταρίας προσφέρουν καινούριες δυνατότητες για τη διαχείριση της διαθέσιμης ενέργειας στα Ασύρματα Δίκτυα Αισθητήρων. Στο πρώτο πεδίο, έχει αποδειχθεί ότι, μέσω ισχυρά συζευγμένων μαγνητικών συντονισμών, η αποδοτικότητα μεταφοράς 60 watts ισχύος σε απόσταση δύο μέτρων φτάνει το 40% και σε απόσταση ενός μέτρου φτάνει το 75%. Επίσης, εμπορικά προϊόντα που κάνουν χρήση αυτής της τεχνολογίας, ήδη κυκλοφορούν στην αγορά. Στο δεύτερο πεδίο, πραγματοποιήθηκε πρόσφατα άκρως ταχεία φόρτιση με μπαταρίες LiFePO4, επιτρέποντας πλήρη φόρτιση σε μερικά μόνο δευτερόλεπτα. Αυτές οι τεχνολογικές εξελίξεις ανοίγουν το δρόμο προς ένα νέο παράδειγμα για τα Ασύρματα Δίκτυα Αισθητήρων, τα Ασύρματα Επαναφορτιζόμενα Δίκτυα Αισθητήρων, τα οποία αποτελούνται από κόμβους αίσθησης (στάσιμους ή κινητούς) και έναν ή περισσότερους κινητούς κόμβους με υψηλό απόθεμα ενέργειας. Οι τελευταίοι, χρησιμοποιώντας τις προαναφερθείσες τεχνολογίες, επιτυγχάνουν γρήγορη ασύρματη φόρτιση των κόμβων αίσθησης. Με αυτόν τον τρόπο, μας δίνεται η δυνατότητα διαχείρισης του πολύ περιορισμένου πόρου της ενέργειας στο δίκτυο, με περισσότερη λεπτομέρεια και αποδοτικότητα. Σημαντικό είναι το γεγονός ότι, από την προοπτική των κόμβων αίσθησης, η διαχείριση της ενέργειας μπορεί να πραγματοποιηθεί παθητικά και χωρίς την υπολογιστική και επικοινωνιακή επιβάρυνση που εισάγουν σύνθετοι αλγόριθμοι διαχείρισης ενέργειας. Επίσης, η διαδικασία φόρτισης μπορεί να πραγματοποιηθεί με πρωτόκολλα τα οποία μελετώνται και σχεδιάζονται ανεξάρτητα από το υποκείμενο πρωτόκολλο δρομολόγησης που χρησιμοποιείται για την μετάδοση των δεδομένων. Το πρόβλημα. Έστω ένα Ασύρματα Επαναφορτιζόμενο Δίκτυο Αισθητήρων στο οποίο οι κόμβοι αίσθησης μεταδίδουν δεδομένα σε ένα κέντρο ελέγχου χρησιμοποιώντας ένα πρωτόκολλο δρομολόγησης και ο κινητός κόμβος φόρτισης, με απόθεμα ενέργειας σημαντικά μεγαλύτερο από έναν κόμβο αίσθησης, είναι ικανός να αναπληρώνει ασύρματα την ενέργεια των κόμβων αίσθησης. Το πρόβλημα που εξετάζουμε είναι η εύρεση της καλύτερης διαμόρφωσης του κινητού κόμβου φόρτισης, με σκοπό τη βελτίωση της ενεργειακής αποδοτικότητας του δικτύου και της παράτασης της διάρκειας ζωής των κόμβων. Η συνεισφορά μας. Αν και έχουν γίνει ήδη σημαντικές ερευνητικές προσπάθειες για την ενεργειακά αποδοτική δρομολόγηση του κινητού κόμβου αίσθησης, οι περισσότερες προτεινόμενες λύσεις στη βιβλιογραφία μέχρι στιγμής υποθέτουν ολική γνώση επάνω στο δίκτυο. Αντιθέτως, οι λύσεις που παρέχουμε είναι πλήρως κατανεμημένες και προσαρμοστικές, και βασίζονται σε τοπική δικτυακή πληροφορία. Επίσης, τα πρωτόκολλά μας για τον κινητό κόμβο αίσθησης μπορούν να χρησιμοποιηθούν σε συνδυασμό με κάθε πρωτόκολλο δρομολόγησης και προσαρμόζονται στην κατανομή των κόμβων αίσθησης στο επίπεδο. Τέλος αναγνωρίζουμε και σχεδιάζουμε σημαντικές παραμέτρους της διαδικασίας φόρτισης, όπως i) το ποσό της συνολικής αρχικής ενέργειας του δικτύου που δεσμεύει ο κινητός κόμβος φόρτισης, ii) το επίπεδο στο οποίο πρέπει να αναπληρώνεται η ενέργεια του κάθε κόμβου αίσθησης, iii) ποιες τροχιές πρέπει να ακολουθεί ο κινητός κόμβος φόρτισης ώστε να φορτίσει τους κόμβους αίσθησης. / Recent advances in the fields of wireless energy transmission and batteries material offer new possibilities for managing the available energy in WSNs. In the first field, the technology of highly efficient wireless energy transmission was proposed for efficient, non-radiative energy transmission over mid-range. It has been shown that through strongly coupled magnetic resonances, the efficiency of transferring 60 watts of power over a distance in excess of 2 meters is as high as 40%. Industry research also demonstrated that it is possible to improve transferring 60 watts of power over a distance of up to one meter with efficiency of 75%. At present, commercial products utilizing wireless energy transmission have been available on the market. In the second field, ultra-fast charging was recently realized in LiFePO4 by creating a fast ion-conducting surface phase through controlled off-stoichiometry. These technologies lead the way towards a new paradigm for wireless sensor networks; the Wireless Rechargeable Sensor Networks (WRSNs), which consist of sensor nodes that may be either stationary or mobile, as well as few mobile nodes with high energy supplies. The latter, by using wireless energy transmission technologies are capable of fast charging sensor nodes. This way, the highly constrained resource of energy can be managed in great detail and more efficiently. Another important aspect is the fact that energy management in WRSNs can be performed passively from the perspective of sensor nodes and without the computational and communicational overhead introduced by complex energy management algorithms. Finally, WRSNs allow energy management to be studied and designed independently of the underlying routing protocol used for data propagation. The Problem. Let a Wireless Rechargeable Sensor Network consisting of a set of stationary sensor nodes and a special mobile node called Mobile Charger. The sensor nodes are deployed uniformly at random over a network area and propagate data to a Sink using a routing protocol. The Mobile Charger has finite energy supplies, that are significantly greater than those of a single sensor node, and is capable of charging the sensors. The problem we study is identifying best possible configuration of the Mobile Charger in order to improve energy efficiency and to prolong the lifetime of the network. Our Contribution. While considerable research efforts have been invested into energy efficient scheduling of the Mobile Charger, proposed solutions in the literature so far require a global knowledge of the state of the network. On the contrary, the solutions proposed in this work are fully distributed and adaptive, and rely solely on local information. Furthermore, our proposed algorithm for the Mobile Charger can be used in combination with any underlying routing protocol and adapts on the distribution of sensors in the network area. We identify and investigate the following trade-offs: i) how the total available energy of the network should be split between sensor nodes and the Mobile Charger ii) given that the energy the charger may deliver to the nodes is finite, whether each sensor will be fully or partially charged and iii) what is the trajectory the Mobile Charger should follow in order to charge the sensor nodes.
9

Flux pumping for high-Tc superconducting (HTS) magnets

Geng, Jianzhao January 2017 (has links)
High Tc superconductors are enabling in the generation of extremely high magnetic fields. Flux pumping is a promising technology which can be used to operate HTS magnets without significant loss. In this decade, several HTS flux pumps based on travelling magnetic waves have been developed, yet their physics is still unclear. This thesis established a framework in the area of flux pumping for HTS coils. It revealed the underlying physics of existing travelling wave flux pumps, which is an important theoretical contribution. Based on the thorough understanding of flux pumping mechanism, the author proposed two novel types of flux pumps. The new inventions make flux pumping much easier, more controllable, and much less energy consuming. These flux pumps may promote the future applications of HTS magnets. This thesis can be a guidebook for researchers and engineers in developing flux pumps.
10

Nositelná elektronika / Smart Wearable

Moravec, Luboš January 2016 (has links)
This master’s thesis deals with the explanation of the concept of smart wearables and the different application possibilities. This work also includes examples of finished demonstration devices in this category. Part of this work is devoted to guide the selection of appropriate components for the design of new equipment in the category of smart wearable. The result of this thesis is designed wearable and charging station. This device is able to read user input and display that information on a smart device running under Android system connected via Bluetooth technology.

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