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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

Comparative life cycle impact assessment of a battery electric and a conventional powertrains for a passenger transport ferryboat : A case study of the entire integrated system for vessel propulsion

Mihaylov, Veselin January 2014 (has links)
This master thesis represents a life cycle impact assessment of a state of the art electrically driven power train. It is expected to be installed in a diesel engine passenger ferry boat, currently transporting passengers in downtown Stockholm archipelago. The assessment has a comparative character in between the currently operating and the new power train in order to differentiate and recognize which of the two propulsion options is the environmentally preferable choice. The scope of the study is directed towards the thorough examination of both power trains so that it can represent most closely the two specific technological cases. Studied and assessed were the three main life cycle phases of each power train – raw materials acquisition and manufacturing, use phase and end of life phase. The fundament of the study involved creating environmental models for each and every component of the drive trains, the propulsion fuel and energy used, and the services related to waste treatment in the last phase of their functional life. The environmental models were later used to build live cycle inventories that served to derive the respectful impact from the item analyzed. The data used to model the battery electric power train was provided directly from the manufacturer, where the end of life procedures carried out were assumed where possible. The main battery pack for the electric power train was not modeled in terms of  end of life procedures due to insufficiency of information. Almost no generic information was available to model the diesel engine and it was calculated by creating auxiliary simplified cad models. The rest of the data required to achieve an environmental inventory regarding the power train was available from a subcontractor. Both studied options were modeled with allocation approach that includes the avoided production of materials at the waste treatment stage where there was sufficient information to do that. There was none to model the main battery packs avoided production which is a major component of the battery electric system. To model the use phase of the diesel engine power train, research data regarding combustion emissions and waterborne emissions was utilized. A number of electricity mix models were applied to create a sensitivity analysis of the operation phase of the battery electric power train. Chosen for baseline scenarios simulating the use phases of both power trains are use of Nordel market electricity mix and the combustion of low sulfur diesel with five volumetric percent rape methyl ester additive. For the purposes of the assessment eighteen midpoint impact indicators were used to cover the areas of global warming potential, human health and quality of eco systems. The results from the study show that the estimated impact from both power trains is small enough to have almost no influence on the results from the two baseline scenarios. Based on this it was concluded that for future research of similar cases either generic information can be used or a cut-off can be applied. After the assessment, more environmentally favorable was estimated the diesel engine power train because of the large burdens from the battery manufacturing in the battery electric option. Further assessment determined that the diesel engine power train again is less environmentally intensive than the battery electric with the main battery burdens excluded. In the overall life cycle impact assessment both power train showed different results in the different impact categories, which could not place a definitive propulsion option of choice. The conclusions from the analysis are that the diesel engine power train causes higher impact in the categories related to global warming, fossil depletion and in most ecosystems quality indicators. The battery electric version in its base line scenario, on the other hand, expresses higher impact in categories related to human health and in the remaining eco system quality midpoint-scores.
2

Eco-routing and scheduling of Connected and Autonomous Vehicles

Houshmand, Arian 19 May 2020 (has links)
Connected and Autonomous Vehicles (CAVs) benefit from both connectivity between vehicles and city infrastructures and automation of vehicles. In this respect, CAVs can improve safety and reduce traffic congestion and environmental impacts of daily commutes through making collaborative decisions. This dissertation studies how to reduce the energy consumption of vehicles and traffic congestion by making high-level routing decisions of CAVs. The first half of this dissertation considers the problem of eco-routing (finding the energy-optimal route) for Plug-In Hybrid Electric Vehicles (PHEVs) to minimize the overall energy consumption cost. Several algorithms are proposed that can simultaneously calculate an energy-optimal route (eco-route) for a PHEV and an optimal power-train control strategy over this route. The results show significant energy savings for PHEVs with a near real-time execution time for the algorithms. The second half of this dissertation tackles the problem of routing for fleets of CAVs in the presence of mixed traffic (coexistence of regular vehicles and CAVs). In this setting, all CAVs belong to the same fleet and can be routed using a centralized controller. The routing objective is to minimize a given overall fleet traveling cost (travel time or energy consumption). It is assumed that regular vehicles (non-CAVs) choose their routing decisions selfishly to minimize their traveling time. A framework is proposed that deals with the routing interaction between CAVs and regular uncontrolled vehicles under different penetration rates (fractions) of CAVs. The results suggest collaborative routing decisions of CAVs improve not only the cost of CAVs but also that of the non-CAVs. This framework is further extended to consider congestion-aware route-planning policies for Autonomous Mobility-on-Demand (AMoD) systems, whereby a fleet of autonomous vehicles provides on-demand mobility under mixed traffic conditions. A network flow model is devised to optimize the AMoD routing and rebalancing strategies in a congestion-aware fashion by accounting for the endogenous impact of AMoD flows on travel time. The results suggest that for high levels of demand, pure AMoD travel can be detrimental due to the additional traffic stemming from its rebalancing flows, while the combination of AMoD with walking or micromobility options can significantly improve the overall system performance.
3

MODELLING AND DESIGN OF ELECTRIC MACHINES AND ASSOCIATED COMPONENTS FOR MORE ELECTRIC VEHICLES

Zhao, Nan January 2017 (has links)
Concerns with emissions, CO2 in particular, and energy resource associated with conventional internal combustion engine (ICE) vehicles is motivating a shift towards more electrified power-trains for road transportation, as well as other transportation applications. The modelling, characterization and design of electrified power-trains, including energy storage technologies, traction machine technologies and their associated power electronics, are discussed in this thesis. Port cranes are a special case of land transportation encompassing many of the power-train objectives found common with road based hybrid electric vehicles; here a port crane system is studied. The power flow for a typical crane loading cycle is analyzed and the value of the energy consumption and saving potential is calculated. Then alternative energy storage applications are considered for hybrid power-train configurations employing diesel engine generators, battery packs, supercapacitors (SCs), and flywheels. A hybrid rubber tyred gantry crane (RTGC) power-train model with power management is developed and the battery-SC hybrid energy storage systems are designed for both short- and long-period operation. The Induction machine (IM) is a popular technology for traction applications. Although many publications discuss IM design to realize a traction torque-speed characteristic, the IM model is studied to determine the main parameters impacting on the machine performance capability at constant torque and extended speed. Based on the model analysis, an IM design procedure for traction applications is proposed which improves machine performance capability. The machine design parameters are normalized in per unit form and hence the proposed design procedure is applicable across different ratings. In the specification and definition of vehicle power-trains, it is common (in industry) to quote data at specific operating conditions, for example, full or fixed battery terminal voltage and system temperature. The interactive influence between energy storage devices and the vehicle system is investigated. Using the all-electric Nissan Leaf power-train as a reference example, the Nissan Leaf traction system is evaluated and performance assessed by considering DC-link voltage variation from battery full state of charge (SoC) to zero SoC and temperature variations typical of an automotive application, showing that the system stated performance is reduced as battery SoC decreases. An alternative traction machine design is proposed to satisfy the vehicle target performance requirements over the complete variation of SoC. The vehicle power-train is then modified with the inclusion of a DC/DC converter between the vehicle battery and DC-link to maintain the traction system DC-link voltage near constant. A supercapacitor system is also considered for improved system voltage management. The trade-offs between the actual Nissan Leaf power-train and the redesigned systems are discussed in terms of electronic and machine packaging, and mitigation of faulted operation at high speeds. Using the Nissan Leaf interior permanent magnet (IPM) machine as the benchmark machine, an example surface permanent magnet (SPM) machine, with same design constraints, is designed and compared with the benchmark IPM machine. The phase voltage distortion of IPM and SPM machines are compared and the mechanisms are revealed. An alternative machine topology with pole shoe rotor is proposed for reduction of machine peak current rating and voltage distortion. The pole shoe topology is common in industrial variable speed drives employing constant torque regimes, but not for traction. Here, the machine with pole shoe rotor is designed to achieve traction performance. The pole shoe concept for vehicle traction is significantly different from existing practice in the electric and hybrid electric automotive industry and thus departure in standard design is a contribution of this thesis. / Thesis / Doctor of Philosophy (PhD)
4

Řešení dynamiky pohonné jednotky ve vozidle / Solution of Powertrain Dynamics in Vehicle

Hodas, David January 2014 (has links)
The main aim of this diploma thesis is to evaluate and select the most appropriate option how to mount a power unit in Formula Student vehicle. It assesses an overall dynamic behaviour of a drive unit mounted in student formula. At the end of the final thesis is an assessment of proposed engine mount variants. The study of parameters that most influence engine vibrations can be seen there.
5

Design, Validation, and Optimization of a Rear Sub-frame with Electric Powertrain Integration

Walters, David Michael 18 September 2015 (has links)
No description available.
6

Jak dlouho by musela jezdit stará škodovka, aby vyprodukovala tolik emisí, jako by vyprodukovala výroba jednoho nového ekologického auta? / How long would it have to an old Skoda car to drive, that produced as many emissions as produced the production of new environmental car

Jurečková, Šárka January 2010 (has links)
This thesis covers primarily the detection of operating emission of an old Škoda Felicia car and the emission produced during the manufacturing of a new Toyota Prius, as the selected representative of an ecological car. The thesis also touches on hybrid technology in itself, the question of the greenness of hybrid cars, sphere of emission, but also related problems so called "scrapping" and its influence on environment and also current situation in automobile industry. The target of this study is calculation of operation time of an old Škoda Felicia during which the CO2 emission will reach the same amount of emission produced during manufacturing of a Toyota Prius. The objective is to point out incompetent and therefore not always serious comparison of cars greenness when only the operating CO2 is being compared. Other energy consumption and therefore also the greenhouse gases production is related with the car manufacturing, raw material extraction, petroleum processing and other economic sectors affected by production. Emission laboratory measurement executed by TÜV SÜD Czech discovered that the old Škoda produces 260m/km CO2 during its real running time. For the emission calculation was used an American model EIO-LCA created by Green Design Institute at Carnegie Mellon University that records ecological influence of car production, in stated amount, on all economy sectors. The outputs are quoted in CO2 equivalent. According to this model during manufacturing of 1 hybrid car 13.5 t of CO2e (equivalent CO2). is produced. Recalculation found out that the old Škoda Felicia could run for more than 5 years in order to produce as much emission as the manufacturing of new Toyota Prius third generation.
7

Raupenfahrzeug-Dynamik

Graneß, Henry 18 April 2018 (has links) (PDF)
Bei Raupenfahrwerken wird das allgemeingültige Prinzip verfolgt, dass durch die scharnierbare Aneinanderreihung von Kettengliedern eine fahrzeugeigene Fahrstrecke entsteht. Dies erlaubt selbst schwere Geräte im unwegsamen, brüchigen Gelände mit großen Vortriebskräften zu mobilisieren. Jedoch wohnt, der Diskretisierung des Raupenbandes in Glieder endlicher Länge geschuldet, dem Fahrwerk eine hohe Fahrunruhe inne. Dadurch entstehen zeitvariante Lasten im Fahrwerk, welche die Lebensdauer der Kette, des Fahrwerkantriebs und der Tragstruktur des Fahrzeugs limitieren und somit regelmäßig kostenintensive Instandsetzungsmaßnahmen erzwingen. Diese Problemstellung aufgreifend beschäftigt sich die Arbeit mit der Analyse und Optimierung des fahrdynamischen Verhaltens von Raupenfahrzeugen. Zugleich werden Methoden vorgestellt, welche eine rechenzeiteffiziente Simulation von Raupenfahrzeugen und Antriebssystemen zulassen.
8

Raupenfahrzeug-Dynamik

Graneß, Henry 27 March 2018 (has links)
Bei Raupenfahrwerken wird das allgemeingültige Prinzip verfolgt, dass durch die scharnierbare Aneinanderreihung von Kettengliedern eine fahrzeugeigene Fahrstrecke entsteht. Dies erlaubt selbst schwere Geräte im unwegsamen, brüchigen Gelände mit großen Vortriebskräften zu mobilisieren. Jedoch wohnt, der Diskretisierung des Raupenbandes in Glieder endlicher Länge geschuldet, dem Fahrwerk eine hohe Fahrunruhe inne. Dadurch entstehen zeitvariante Lasten im Fahrwerk, welche die Lebensdauer der Kette, des Fahrwerkantriebs und der Tragstruktur des Fahrzeugs limitieren und somit regelmäßig kostenintensive Instandsetzungsmaßnahmen erzwingen. Diese Problemstellung aufgreifend beschäftigt sich die Arbeit mit der Analyse und Optimierung des fahrdynamischen Verhaltens von Raupenfahrzeugen. Zugleich werden Methoden vorgestellt, welche eine rechenzeiteffiziente Simulation von Raupenfahrzeugen und Antriebssystemen zulassen.:Inhaltsverzeichnis V Symbolverzeichnis VIII Abkürzungsverzeichnis XII 1 Einleitung 1 1.1 Eigenschaften und Anwendungsbereiche von Raupenfahrwerken 1 1.2 Problemstellung 2 1.3 Gesamtaufbau Bagger 293 4 1.4 Raupenfahrwerk Bagger 293 5 1.5 Raupenfahrwerk – Fahrschiff 6 1.6 Präzisierte Aufgabenstellung 7 2 Grundlagen und Stand der Technik 11 2.1 Grundlagen zur Fahrunruhe von Raupenfahrwerken 11 2.1.1 Allgemeine Einteilung der Fahrunruhe 11 2.1.2 Innere Fahrwiderstände 12 2.1.3 Äußere Fahrwiderstände 18 2.1.4 Kettenvorspannung 19 2.2 Arbeiten zur Beschreibung der Fahrunruhe von Raupenfahrwerken 20 2.3 Ganzheitliche Analyse von Raupenfahrzeugen 22 2.3.1 Ganzheitliche Systembetrachtung 22 2.3.2 Beiträge zur ganzheitlichen Raupenfahrzeuganalyse 22 3 Detaillierte Modellfindung von Raupenfahrzeugkomponenten 26 3.1 Hintergrund 26 3.2 Elektrisch-Regelungstechnisches System 27 3.2.1 Regelungsprinzip für das einzelne Fahrschiff 27 3.2.2 Regelungsprinzip für das gesamte Fahrwerk 27 3.2.3 PI-Drehzahlregelung 29 3.2.4 P-Drehzahldifferenzregelung 30 3.2.5 Lenkwinkelkorrektur 31 3.2.6 Asynchronmaschine 33 3.2.7 Feldorientierte Regelung 37 3.2.8 Frequenzumrichter 40 3.2.9 Simulation und Analyse des Einzelraupenmodells der Regelung 41 3.3 Fahrwerksmodell 43 3.3.1 Modellbildung und Topologie 43 3.3.2 Fahrsimulation ohne Schakentäler 46 3.3.3 Fahrsimulation mit Schakentälern 51 3.3.4 Fahrsimulation Hangfahrt mit Schakentälern 54 3.3.5 Fahrsimulation Kurvenfahrt mit Schakentälern 56 3.3.6 Sensitivität des Fahrverhaltens 59 3.3.7 Fazit zur Fahrdynamik eines Fahrschiffes 63 3.4 Mechanisches System – Getriebe 63 3.4.1 Modellbildung und Topologie 63 3.4.2 Simulation mit synthetischem Lastfall 67 3.5 Mechanisches System – Unterwagen und Oberbau 69 3.5.1 Modellbildung 69 3.5.2 Simulation im Frequenzbereich 71 4 Rechenzeiteffiziente Ersatzmodelle von Raupenfahrzeugkomponenten 72 4.1 Hintergrund 72 4.2 Elektrisch-Regelungstechnisches System 72 4.2.1 Methodik 72 4.2.2 Simulation und Bewertung 73 4.3 Fahrwerksmodell 74 4.3.1 Methodik 74 4.3.2 Simulation und Bewertung ohne Schakentäler 87 4.3.3 Simulation und Bewertung mit Schakentälern 90 4.4 Getriebemodell 92 4.4.1 Methodik 92 4.4.2 Simulation und Bewertung 96 4.5 Unterwagen- und Oberbaumodell 98 4.5.1 Methodik 98 4.5.2 Simulation und Bewertung 99 5 Ganzheitliche Fahrdynamik-Simulation und Messdatenabgleich 101 5.1 Modellstufen 101 5.1.1 Rheonom betriebenes Fahrschiffmodell 101 5.1.2 Ganzheitliches Fahrschiffmodell 101 5.1.3 Ganzheitliches Fahrzeugmodell 102 5.2 Simulation 103 5.2.1 Vergleich des rheonomen mit dem ganzheitlichen Fahrschiffmodell 103 5.2.2 Einfluss der Oberbauelastizität auf das Fahrverhaltens 104 5.2.3 Einfluss der Phasenlage (Parallelfahrt) 105 5.2.4 Vergleich Messung und Simulation 108 6 Ganzheitliche Optimierung am Fahrschiffmodell 115 6.1 Methodik 115 6.2 Kontinuierliche Rollbahn 115 6.2.1 Hintergrund 115 6.2.2 Erprobung am Ersatzmodell des Fahrwerkes 116 6.2.3 Erprobung am MKS-Kontaktmodell des Fahrwerkes 117 6.3 PI-Motordrehzahlregelung 118 6.3.1 Hintergrund 118 6.3.2 Erprobung am Ersatzmodell mit Schakental-Design 119 6.3.3 Erprobung am MKS-Kontanktmodell mit Schakental-Design 122 6.3.4 Erprobung am Ersatzmodell mit kontinuierlicher Rollbahn 124 6.3.5 Erprobung am MKS-Kontaktmodell mit kontinuierlicher Rollbahn 126 6.3.6 Fazit PI-Drehzahlregelung 127 6.4 PI-Zustandsregelung 127 6.4.1 Methodik 127 6.4.2 Erprobung am Ersatzmodell mit Schakental-Design 133 6.4.3 Erprobung am MKS-Kontaktmodell mit Schakental-Design 135 6.4.4 Erprobung am Ersatzmodell mit kontinuierlicher Rollbahn 135 6.4.5 Erprobung am MKS-Kontaktmodell mit kontinuierlicher Rollbahn 137 6.4.6 Fazit PI-Zustandsregelung 138 6.5 Statische und statisch-dynamische Kettenvorspannung 139 6.5.1 Hintergrund 139 6.5.2 Erprobung am Ersatzmodell 140 6.5.3 Erprobung am MKS-Kontaktmodell 142 6.5.4 Kritische Bewertung 143 7 Ganzheitliche Optimierung am Fahrzeugmodell 144 7.1 Methodik 144 7.2 Kontinuierliche Rollbahn 144 7.3 Kontinuierliche Rollbahn und statische Kettenvorspannung 145 8 Zusammenfassung und Ausblick 146 Literatur 149 Abbildungsverzeichnis 154 Tabellenverzeichnis 159 A Auswertungsgrößen 160 A.1. Amplitudensignal 160 A.2. Schwingungseffektivwert 160 A.3. Kreuzkorrelationskoeffizient 161 B Analytische Berechnung der Lasten bei Kurvenfahrt 162 C Korrelationen CB-Set 164
9

FC³ - 2nd Fuel Cell Conference Chemnitz 2022 - Saubere Antriebe. Effizient Produziert.: Wissenschaftliche Beiträge und Präsentationen der zweiten Brennstoffzellenkonferenz am 31. Mai und 01. Juni 2022 in Chemnitz

von Unwerth, Thomas, Drossel, Welf-Guntram 27 May 2022 (has links)
Die zweite Chemnitzer Brennstoffzellenkonferenz wurde vom Innovationscluster HZwo und dem Fraunhofer-Institut für Werkzeugmaschinen und Umformtechnik IWU durchgeführt. Ausgewählte Fachbeiträge und Präsentationen werden in Form eines Tagungsbandes veröffentlicht. / The second fuel cell conference was initiated by the innovation cluster HZwo and the Fraunhofer Institute for Machine Tools and Forming Technology. Selected lectures and presentations are published in the conference proceedings.
10

A fundamental approximation in MATLAB of the efficiency of an automotive differential in transmitting rotational kinetic energy

Vaughn, James Roy 30 July 2012 (has links)
The VCOST budgeting tool uses a drive cycle simulator to improve fuel economy predictions for vehicle fleets. This drive cycle simulator needs to predict the efficiency of various components of the vehicle's powertrain including any differentials. Existing differential efficiency models either lack accuracy over the operating conditions considered or require too great an investment. A fundamental model for differential efficiency is a cost-effective solution for predicting the odd behaviors unique to a differential. The differential efficiency model itself combines the torque balance equation and the Navier-Stokes equations with models for gear pair, bearing, and seal efficiencies under a set of appropriate assumptions. Comparison of the model with existing data has shown that observable trends in differential efficiency are reproducible in some cases to within 10% of the accepted efficiency value over a range of torques and speeds that represents the operating conditions of the differential. Though the model is generally an improvement over existing curve fits, the potential exists for further improvement to the accuracy of the model. When the model performs correctly, it represents an immense savings over collecting data with comparable accuracy. / text

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