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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

Evaluation of hybrid-electric propulsion systems for unmanned aerial vehicles

Matlock, Jay Michael Todd 14 January 2020 (has links)
The future of aviation technology is transitioning to cleaner, more efficient and higher endurance aircraft solutions. As fully electric propulsion systems still fall short of the operational requirements of modern day aircraft, there is increasing pressure and demand for the aviation industry to explore alternatives to fossil fuel driven propulsion systems. The primary focus of this research is to experimentally evaluate hybrid electric propulsion systems (HEPS) for Unmanned Aerial Vehicles (UAV) which combine multiple power sources to improve performance. HEPS offer several potential benefits over more conventional propulsion systems such as a smaller environmental impact, lower fuel consumption, higher endurance and novel configurations through distributed propulsion. Advanced operating modes are also possible with HEPS, increasing the vehicle’s versatility and redundancy in case of power source failure. The primary objective of the research is to combine all of the components of a small-scale HEPS together in a modular test bench for evaluation. The test bench uses components sized for a small-scale UAV including a 2.34kW two-stroke 35cc engine and a 1.65kW brushless DC motor together with an ESC capable of regenerative braking. Individual components were first tested to characterize performance, and then all components were assembled together in a parallel configuration to observe system-level performance. The parallel HEPS is capable of functioning in the four required operating modes: EM Only, ICE Only, Dash Mode (combined EM and ICE power) as well as Regenerative Mode where the onboard batteries get recharged. Further, the test bench was implemented with a supervisory controller to optimize system performance and run each component in the most efficient region to achieve torque requirements programmed into mission profiles. The logic based controller operates with the ideal operating line (IOL) concept and is implemented with a custom LabView GUI. The system is able to run on electric power or ICE power interchangeably without making any modifications to the transmission as the one-way bearing assembly engages for whichever power source is rotating at the highest speed. The most impressive of these sets of tests is the Dash mode testing where the output torque of the propeller is supplied from both the EM and ICE. Working in tandem, it was proved that the EM was drawing 19.9A of current which corresponds to an estimated 0.57Nm additional torque to the propeller for a degree of hybridization of 49.91%. Finally, the regenerative braking mode was proven to be operational, capable of recharging the battery systems at 13A. All of these operating modes attest to the flexibility and convenience of having a hybrid-electric propulsion system. The results collected from the test bench were validated against the models created in the aircraft simulation framework. This framework was created in MATLAB to simulate the performance of a small UAV and compare the performance by swapping in various propulsion systems. The purpose of the framework is to make direct comparisons of HEPS performance for parallel and series architectures against conventional electric and gasoline configuration UAVs, and explore the trade-offs. Each aircraft variable in the framework was modelled parametrically so that parameter sweeps could be run to observe the impact on the aircraft’s performance. Finally, rather than comparing propulsion systems in steady-state, complex mission profiles were created that simulate real life applications for UAVs. With these experiments, it was possible to observe which propulsion configurations were best suited for each mission type, and provide engineers with information about the trade-offs or advantages of integrating hybrid-electric propulsion into UAV design. In the Pipeline Inspection mission, the exact payload capacities of each aircraft configuration could be observed in the fuel burn versus CL,cruise parameter sweep exercise. It was observed that the parallel HEPS configuration has an average of 3.52kg lower payload capacity for the 35kg aircraft (17.6%), but has a fuel consumption reduction of up to 26.1% compared to the gasoline aircraft configuration. In the LIDAR Data collection mission, the electric configuration could be suitable for collection ranges below 100km but suffers low LIDAR collection times. However, at 100km LIDAR collection range, the series HEPS has an endurance of 16hr and the parallel configuration has an endurance of 19hr. In the Interceptor mission, at 32kg TOW, the parallel HEPS configuration has an endurance/TOW of 1.3[hr/kg] compared to 1.15[hr/kg] for the gasoline aircraft. This result yields a 13% increase in endurance from 36.8hr for gasoline to 41.6hr for the parallel HEPS. Finally, in the Communications Relay mission, the gasoline configuration is recommended for all TOW above 28kg as it has the highest loiter endurance. / Graduate
2

Modeling and Control of a Parallel HEV Powertrain with Focus on the Clutch

Morsali, Mahdi January 2015 (has links)
Nowadays, the increasing amount of greenhouse gases and diminishing of the existing petroleum minerals for future generations, has led the automotive companies to think of producing vehicles with less emissions and fuel consumption. For this purpose, Hybrid Electric Vehicles (HEVs) have emerged in the recent decades. HEVs with different configurations have been introduced by engineers.The simulation platform aim for a parallel HEV, where the intention is to reduce the emissions and fuel consumption. The simulation platform includes an Electric Motor (EM) in addition to an Internal Combustion Engine (ICE). A new transmission system is modeled which is compatible with parallel configuration for the HEV, where the inertial effects of the gearbox, clutch and driveline is formulated. The transmission system includes a gearbox which is equipped with synchronizers for smooth change of gears. The HEV is controlled by a rule based controller together with an optimization algorithm as power management strategy in order to have optimal fuel consumption. Using the rule based controller, the HEV is planned to be launched by EM in order to have a downsized clutch and ICE. The clutch modeling is the main focus of this study, where the slipping mechanism is considered in the simulation. In the driveline model, the flexibility effects of the propeller shaft and drive shaft is simulated, so that the model can capture the torsional vibrations of the driveline. The objective of modeling such a system is to reduce emissions and fuel consumption with the same performance of the conventional vehicle. To achieve this goal first a conventional vehicle is modeled and subsequently, a hybrid vehicle is modeled and finally the characteristics of the two simulated models are studied and compared with each other. Using the simulation platform, the state of charge (SOC) of the battery, oscillations of propeller shaft and drive shaft, clutch actuations and couplings, energy dissipated by the clutch, torques provided by EM and ICE, fuel consumptions, emissions and calculation time are calculated and investigated. The hybridization results in a reduction in fuel consumption and emissions, moreover, the energy dissipated by the clutch and clutch couplings are decreased.
3

Supervisory Control Optimization with Sequential Quadratic Programming for Parallel Hybrid Vehicle with Synchronous Power Sources

January 2017 (has links)
abstract: The thesis covers the development and modeling of the supervisory hybrid controller using two different methods to achieve real-world optimization and power split of a parallel hybrid vehicle with a fixed shaft connecting the Internal Combustion Engine (ICE) and Electric Motor (EM). The first strategy uses a rule based controller to determine modes the vehicle should operate in. This approach is well suited for real-world applications. The second approach uses Sequential Quadratic Programming (SQP) approach in conjunction with an Equivalent Consumption Minimization Strategy (ECMS) strategy to keep the vehicle in the most efficient operating regions. This latter method is able to operate the vehicle in various drive cycles while maintaining the SOC with-in allowed charge sustaining (CS) limits. Further, the overall efficiency of the vehicle for all drive cycles is increased. The limitation here is the that process is computationally expensive; however, with advent of the low cost high performance hardware this method can be used for the hybrid vehicle control. / Dissertation/Thesis / Masters Thesis Engineering 2017
4

A STRATEGY TO BLEND SERIES AND PARALLEL MODES OF OPERATION IN A SERIES-PARALLEL 2-BY-2 HYBRID DIESEL/ELECTRIC VEHICLE

Picot, Nathan M. January 2007 (has links)
No description available.
5

Modelling, design and energy management of a hybrid electric ship – a case study

Zhu, Haijia 05 May 2020 (has links)
The widely-used passenger and car ferries, sailing regularly and carrying heavy loads, form a unique type of marine vessel, providing vital transportation links to the coastal regions. Modern ferry ships usually are equipped with multiple diesel engines as prime movers. These diesel engines consume a large amount of marine diesel fuel with high fuel costs, and high emissions of greenhouse gas (GHG) and other harmful air pollutants, including CO2, HC, NOx, SO2, CO, and PM. To reduce fuel costs and the harmful emissions, the marine industry and ferry service providers have been seeking clean ship propulsion solutions. In this work, the model-based design (MBD) and optimization methodology for developing advanced electrified vehicles (EV) are applied to the modelling, design and control optimizations of clean marine vessels with a hybrid electric propulsion system. The research focuses on the design and optimization of the hybrid electric ship propulsion system and uses an open deck passenger and car ferry, the MV Tachek, operated by the British Columbia Ferry Services Inc. Canada, as a test case. At present, the ferry runs on the Quadra Island – Cortes Island route in British Columbia, Canada, with dynamically changing ocean conditions in different seasons over a year. The research first introduces the ship operation profile, using statistical ferry operation data collected from the ferry’s voyage data recorder and a data acquisition system that is specially designed and installed in this research. The ship operation profile model with ship power demand, travelling velocity and sailing route then serves as the design and control requirements of the hybrid electric marine propulsion system. The development of optimal power control and energy management strategies and the optimization of the powertrain architecture and key powertrain component sizes of the ship propulsion system are then carried out. Both of the series and parallel hybrid electric propulsion architectures have been studied. The sizes of crucial powertrain components, including the diesel engine and battery energy storage system (ESS), are optimized to achieve the best system energy efficiency. The optimal power control and energy management strategies are optimized using dynamic programming (DP) over a complete ferry sailing trip. The predicted energy efficiency and emission reduction improvements of the proposed new ship with the optimized hybrid propulsion system are compared with those of two benchmark vessels to demonstrate the benefits of the new design methodology and the optimized hybrid electric ship propulsion system design. These two benchmarks include a conventional ferry with the old diesel-mechanical propulsion system, and the Power Take In (PTI) hybrid electric propulsion systems installed on the MV Tachek at present. The simulation results using the integrated ship propulsion system model showed that the newly proposed hybrid electric ship could have 17.41% fuel saving over the conventional diesel-mechanical ship, and 22.98% fuel saving over the present MV Tachek. The proposed optimized hybrid electric propulsion system, combining the advantages of diesel-electric, pure electric, and mechanical propulsions, presented considerably improved energy efficiency and emissions reduction. The research forms the foundation for future hybrid electric ferry design and development. / Graduate
6

Development and Testing of Control Strategies for the Ohio State University EcoCAR Mobility Challenge Hybrid Vehicle

Rangarajan, Hariharan January 2021 (has links)
No description available.
7

Systematische, rechnergestützte Generierung konventioneller und hybrider Antriebsstränge für automobile Anwendungen / Systematic, computer-aided generation of conventional and hybrid power trains for automobile applications

Müller, Jörg 11 May 2011 (has links) (PDF)
Im Vortrag werden die komplexen und teilweise konträren Herausforderungen an zukünftige automobile Antriebsstränge und Getriebesysteme vorgestellt. Die klassische Suche nach neuen Antriebssträngen, basierend auf Intuition und Expertenwissen, kann diesen vielseitigen Zielstellungen kaum noch gerecht werden. Aus diesem Grund wird ein neuer methodischer Ansatz vorgestellt, mit dem konventionelle und hybride Getriebekonzepte rechnergestützt generiert werden können. Die Voraussetzung dafür bildet die eindeutige und kompakte mathematische Abbildung von beliebigen Getriebesystemen oder ganzen Antriebssträngen im Computer auf Basis eines Wellenmodells. Diese Codierung lässt sich effizient hinsichtlich diverser kinematischer und kinetischer Belastungen für frei wählbare Freiheitsgrade analysieren. Die rechnergestützte Synthese und Bewertung neuer Getriebe wird am Beispiel von Planetenautomatikgetrieben vorgestellt, wobei alle kombinatorisch möglichen konventionellen und hybriden Systeme Beachtung finden. Beispielsweise werden für eine aktuell typische Anzahl an Planetenradsätzen und Schaltelementen mehrere hundert Milliarden Getriebevarianten untersucht. Am Ende eines Syntheselaufs werden dem Entwicklungsingenieur die besten Systeme in einem Ranking vorgeschlagen. Der Vortrag schließt mit der Vorstellung exemplarischer Ergebnisse dieser neuen Entwicklungsmethode. Das neue Achtgang-Hybrid-Automatikgetriebe und das neue Neungang-Hybrid-Doppelkupplungsgetriebe verdeutlichen die Entwicklungspotentiale zukünftiger Getriebesysteme, bei denen hochfunktionale und effiziente Eigenschaften mit kleinstmöglichem mechanischem Aufwand, geringen Kosten und Bauraum kombiniert werden. Die IAV GmbH nutzt dieses Entwicklungstool erfolgreich zur Erzeugung von verschiedenen Getriebearten, wie Planetenautomatikgetrieben, Doppelkupplungsgetrieben, Handschaltgetrieben und stufenlos leistungsverzweigten Getrieben mit mechanischem oder elektrischem Variator.
8

Plataforma computacional híbrida de coprocessamento paralelo distribuído por web services aplicada à radiointerferometria

Silva, Gustavo Poli Lameirão da 19 August 2013 (has links)
Made available in DSpace on 2016-06-02T19:03:58Z (GMT). No. of bitstreams: 1 5593.pdf: 13078959 bytes, checksum: 1cc88a226e87c0a4ca26af32176acea5 (MD5) Previous issue date: 2013-08-19 / Financiadora de Estudos e Projetos / The requirements imposed by the new applications presents great challenges to the computation. There is not a perfect computer architecture, capable to attend to all the requirements. The parallel and hybrid computer arrangement rise as a solution to this scenario i.e., the CPU-Coprocessor pair arrangement can form a specialized computerized instrument for a special application task. This doctoral thesis proposes a parallel and hybrid computational platform denoted CoP-WS, that uses the interoperability technology known as Web Services. As coprocessor it is used the graphic processing unit, known as the GPU, functioning recently as parallel thread level processing of general use applications. The platform test of feasibility was inspired in radio astronomy, and it has been implemented two applications: a complex correlator of signals provided by a radio interferometric arrangement, and a flare recognition system with a solar radio interferometer image. Both processings can be inserted in the context of pipeline execution, using sufficient configuration of CPU-GPU pairs, having on one side the interferometric arrangement antenna signal input and in the other side the result of the solar flare recognition. The obtained results of the both applications show the feasibility of the CoP-WS platform, for greater volume of data being processed in quasi real time. In the case of the correlator the average processing time in each integration period was around 160 ms, and in the case of the solar flare recognition, 48 ms for each solar disk image. / Os requisitos impostos pelas novas aplicações, sejam estas científicas, ou não, apresentam grandes desafios à computação. Não existe uma arquitetura de computadores "perfeita" que seja capaz de atender a todos estes requisitos. A configuração de arranjos paralelos e híbridos de computadores se apresenta como uma solução para este cenário, ou seja, a configuração de arranjos de pares CPU-Coprocessador, pode ser especializada para o processamento de uma aplicação distintas. Este trabalho de doutorado propõe uma plataforma computacional paralela e híbrida distribuída denominada CoP-WS, que utiliza a tecnologia de interoperabilidade conhecida como Web Services. Como coprocessador é utilizada a unidade de processamento gráfico conhecida como GPU, cuja função tem sido de processamento paralelo ao nível de threads, para aplicações gerais nos últimos tempos. A prova de viabilidade da plataforma implementada foi inspirada na radioastronomia, tendo sido implementados dois aplicativos: um correlacionador complexo de sinais provindos dos arranjos interferométricos e um sistema para o reconhecimento de explosões solares, numa imagem de radiointerferometria solar. Ambos os processamentos podem ser inseridos num contexto de execução em pipeline, usando uma configuração suficiente de pares CPU-GPU, tendo de um lado a entrada dos sinais das antenas do arranjo interferométrico e do outro lado o resultado do processamento de reconhecimento de explosões solares. Em ambas aplicações os resultados foram satisfatórios sendo que no caso do correlacionador o tempo médio de processamento de cada ciclo de integração foi de aproximadamente 160 ms, e para a aplicação de reconhecimento de explosões solares, de 48 ms por imagem de disco solar.
9

Méthodologie de dimensionnement d’un véhicule hybride électrique sous contrainte de minimisation des émissions de CO2 / Hybrid electric vehicle sizing methodology under CO2 emissions minimization constraint

Marc, Nicolas 26 November 2013 (has links)
Ce travail de thèse propose une méthodologie systématique d’évaluation et de comparaison des gains en émissions de CO2 de véhicules hybrides électriques de différentes architectures et intégrant différentes fonctionnalités. Une méthodologie de dimensionnement a été mise en place, elle se base sur la définition d’un cahier des charges en performances dynamiques des véhicules, la mise en place d’algorithmes de mise à l’échelle afin de générer les données des composants de la chaîne de traction (batterie, machine électrique, moteur thermique), et l’utilisation de procédures de dimensionnement du véhicule sous contrainte de minimisation des émissions de CO2. L’évaluation énergétique des différentes configurations de véhicule ainsi dimensionnées s’articule autour de la définition de différents usages du véhicule et sur l’implémentation d’une loi de gestion optimale de l’énergie de type Principe du Minimum de Pontriaguine. Ces méthodologies ont été appliquées à une architecture conventionnelle, servant de référence pour les performances dynamiques et les consommations énergétiques, et d’une architecture hybride parallèle pré-transmission, pour laquelle une configuration hybride rechargeable et une configuration hybride non rechargeable ont été implémentées. / This thesis work proposes a systematic methodology dedicated to the evaluation and comparison of CO2 emissions’ reduction for hybrid electric vehicles with different architectures and different levels of functionality. A sizing methodology has been developed, which is based on the definition of the requirements for the dynamic performances of vehicles, on the development of scaling algorithms in order to generate the dataset for the powertrain components (battery, electric motor, engine), and on the application of procedures for the sizing of a vehicle under CO2 emissions’ minimization constraint. The energy consumption evaluation of the different vehicle configurations, which were previously sized, is founded on the definition of a variety of vehicle’s type of use, as well as on the implementation of an optimal energy management strategy, the Pontryaguin’s Minimum Principle. These methodologies have been applied to a conventional vehicle architecture, which has been used as a reference for dynamic performances and energy consumption, and to a hybrid parallel pre-transmission architecture, which has been defined in two configurations, a plug-in hybrid and a non plug-in full-hybrid.
10

Μελέτη και κατασκευή κινητήριου συστήματος υβριδικού οχήματος : ενεργειακή διαχείριση μέσω ηλεκτρονικών μετατροπέων ισχύος

Ασημακόπουλος, Παναγιώτης 19 January 2010 (has links)
Η μόλυνση του περιβάλλοντος από τα μέσα μεταφοράς και η συνεχής μείωση των αποθεμάτων των ορυκτών καυσίμων αποτελούν τους δύο κύριους λόγους για τη στροφή των τμημάτων έρευνας της παγκόσμιας αυτοκινητοβιομηχανίας στην επινόηση οικολογικότερων μέσων μετακίνησης. Από αυτή την προσπάθεια προέκυψαν τα ηλεκτρικά υβριδικά οχήματα, τα οποία περιορίζουν την κατανάλωση καυσίμου και τις εκπομπες ρύπων συγκριτικά με συμβατικά οχήματα παραπλήσιων τεχνικών χαρακτηριστικών. Τα υβριδικά οχήματα είναι, ουσιαστικά, ο προάγγελος και το πεδίο δοκιμής και εξέλιξης της αμιγούς ηλεκτροκίνησης. Ο κοινός στόχος της παρούσας διπλωματικής εργασίας και άλλων δύο διπλωματικών εργασιών, οι οποίες εκπονήθηκαν παράλληλα με αυτή, είναι η μετατροπή ενός συμβατικού βενζινοκίνητου αυτοκινήτου σε ηλεκτρικό υβριδικό όχημα. Το αρχικό μέλημα υπήρξε η εύρεση του κατάλληλου οχήματος για τη συγκεκριμένη εφαρμογή. Την προμήθεια του οχήματος ακολούθησε η έρευνα της αγοράς για την εύρεση του κατάλληλου ηλεκτρικού κινητήρα. Ο κινητήρας, ο οποίος επιλέχθηκε, είναι τριφασικός ασύγχρονος. Εν συνεχεία, αγοράστηκαν συσσωρευτές οξέος μολύβδου ως εναλλακτική πηγή ενέργειας του οχήματος. Ακολούθησε εμπεριστατωμένη μελέτη για τη μηχανολογική προσαρμογή του ηλεκτρικού κινητήρα και των συσσωρευτών στο όχημα και πραγματοποιήθηκε αυτή η εργασία. O ηλεκτρικός κινητήρας τοποθετήθηκε επί του διαφορικού, ενώ κατασκευάστηκε ειδική βάση για τους συσσωρευτές. Υπολογίστηκε και κατασκευάστηκε κατάλληλο σύστημα μετάδοσης για τη μεταφορά της κίνησης από τον κινητήρα στον άξονα μετάδοσης της κίνησης του οχήματος, ώστε να ανταποκρίνεται στις ανάγκες κίνησης του. Το γεγονός ότι ο κινητήρας χρειάζεται σύστημα υδρόψυξης για την ασφαλή και αποδοτική λειτουργία του είχε ως αποτέλεσμα την κατασκευή κατάλληλης διάταξης. Το δεδομένο ότι οι συσσωρευτές παράγουν συνεχές ρεύμα, ενώ ο κινητήρας απαιτεί τροφοδοσία με εναλλασσόμενο ρεύμα οδήγησε στην κατασκευή ενός τριφασικού αντιστροφέα ισχύος. Ο αντιστροφέας αποτελεί μια ηλεκτρική διάταξη, η οποία μετατρέπει το συνεχές ρεύμα σε εναλλασσόμενο. Το απαιτούμενο επίπεδο τάσης εξόδου του αντιστροφέα για την τροφοδοσία του κινητήρα προϋποθέτει συγκεκριμένο επίπεδο τάσης στην είσοδο του μετατροπέα, το οποίο είναι υψηλότερο από την τάση εξόδου της συστοιχίας των συσσωρευτών. Επιχειρήθηκε, λοιπόν, η εξομοίωση και η κατασκευή ενός αμφικατευθυντήριου μετατροπέα συνεχούς τάσης σε συνεχή. Η ιδιότητα του είναι η ανύψωση του επιπέδου τάσης των συσσωρευτών κατά τη φάση της τροφοδότησης του κινητήρα αλλά και ο υποβιβασμός της τάσης για τη φόρτιση των συσσωρευτών κατά την επιστροφή ενέργειας από τη λειτουργία του κινητήρα ως γεννήτρια, τη λεγόμενη διαδικασία της αναγεννητικής πέδησης. Ο έλεγχος του ηλεκτρικού κινητήρα πραγματοποιήθηκε μέσω της τεχνικής του άμεσου ελέγχου ροπής (DTC), ενός είδους άμεσου διανυσματικού ελέγχου. / The environmental pollution caused by all means of transport and the continued reduction of stocks of fossil fuels are the two main reasons, which directed the global automotive research in developing “greener” means of transport. From this effort emerged hybrid electric vehicles, which reduce fuel consumption and emissions compared to conventional vehicles with similar technical characteristics. Hybrid vehicles are essentially the precursor and the field for testing and developing pure electric traction. The common objective of this and two other diploma theses, which were prepared in parallel with it, is to convert a conventional gasoline car to a hybrid electric one. The initial concern was to find a suitable vehicle for this application. The supply of the vehicle was followed by the market research to find a suitable motor. The selected motor is a three-phase asynchronous motor. Subsequently, lead acid batteries were purchased as an alternative energy source for the vehicle. This was followed by a thorough study of the mechanical adjustment of the electric motor and battery in the vehicle and the planned work was performed. The electric motor is adapted on the differential and a base was constructed to fit the batteries. A suitable transmission system was built to transmit motion from the electric motor to the transmission axle of the vehicle to meet the needs of the driving conditions. The fact that the motor needs a water cooling system for its safe and efficient operation resulted in the construction of an adequate array. Taking into account that the batteries produce direct current, while the motor requires the supply of alternating current led to the design and construction of a three-phase power inverter at the laboratory. The inverter is an electrical device that converts direct current to alternating current. The demanded level of voltage in the inverter’s output to power the motor requires a specific voltage level at the input of the converter, which is higher than the output voltage of the battery pack. Therefore, the simulation and the construction of a bidirectional DC to DC voltage converter was attempted at the laboratory. The aim is to raise the level of battery voltage during the phase of the electric machine functioning as a motor and to reduce the voltage level to charge the batteries during the phase that the electric machine functions as a generator, a process called regenerative braking. The control of the electric motor was achieved by the technique of direct torque control (DTC), a kind of direct vector control.

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