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Permanent magnet synchronous machine using ferrite vs rare earth magnets : how do they compare? / Synkronmaskin med permanentmagnet som använder ferrit mot sällsynta jordartsmagneter : hur jämför de sig?Manakshya, Nikhil January 2021 (has links)
Permanent magnet synchronous machines (PMSM are considered as viable options for automotive and traction applications. Rare earth magnets such as Neodymium Iron Boron (NdFeB is the most common choice in the PMSM for electric vehicles to achieve high power density machines. However, rare earth magnets are problematic from ethical and sustainability perspectives. From these perspectives, there are better magnet alternatives, such as ferrites. Ferrite magnets are well known for lower environmental impact, abundance and low cost. Due to a lower residual flux density of a ferrite magnet than that of a rare earth magnet, a larger amount of ferrite magnets are needed to achieve the same performance. This master thesis is aimed to compare a PMSM using NdFeB magnets with a PMSM using ferrite magnets in terms of different parameters such as torque production, power factor, drive cycle efficiency, losses mapping, cost, and environmental impact. The machines are designed based on the Volvo XC40 vehicle requirements. In order to compare both the machines, ferrite based machine with different types of rotor structures such as arc and spoke type configurations are designed in Ansys Maxwell and compared with the reference PMSM holding NdFeB magnet. The demagnetisation study was performed on the ferrite magnets at lower temperature in order to investigate the feasibility of the design. In order to reduce the risk of demagnetisation, a parametric analysis of the rotor structure has been conducted. Furthermore, the mechanical integrity was investigated at top speed. / Permanent magnet-synkronmaskiner (PMSM) betraktas som lönsamma alternativ för fordons och dragapplikationer. Sällsynta jordartsmagneter som Neodymiumbor (NdFeB) är det vanligaste valet i PMSM för elfordon att uppnå maskiner med hög effektdensitet. Sällsynta jordartsmagneter är emellertid problematiska ur etiska perspektiv och hållbarhetsperspektiv. Ur dessa perspektiv finns det bättre magnetalternativ, såsom ferriter. Ferrit är välkänt för lägre miljöpåverkan, överflöd och låga kostnader. På grund av låg restflödestäthet hos en ferritmagnet än en sällsynt jordartsmagnet behövs en större mängd ferritmagneter för att uppnå samma prestanda. Detta examensarbete syftar till att jämföra en PMSM med hjälp av NdFeB-magneter med en PMSM som använder ferritmagneter i termer av olika prestandaparametrar såsom vridmomentproduktion, effektfaktor, drivcykeleffektivitet, kartläggning av förluster, kostnad och miljöpåverkan. Maskinerna är designade baserat på Volvo XC40 fordons krav. För att jämföra båda maskinerna utformas ferritbaserad maskin med olika typer av rotorstruktur, såsom båg- och ekertypskonfiguration i Ansys Maxwell och jämförs med referensen PMSM som håller NdFeB-magneten. Demagnetiseringsstudien utfördes på ferritmagneterna vid lägre temperatur för att undersöka designens genomförbarhet. För att minska risken för demagnetisering har den parametriska analysen av rotorstrukturen genomförts. Dessutom undersöktes mekanisk integritet i toppfart.
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Control Design and Analysis of an Advanced Induction Motor Electric Vehicle DriveHerwald, Marc A. 20 May 1999 (has links)
This thesis is about the development and performance enhancement of an induction motor electric vehicle drive system. The fundamental operation of the induction motor drive hardware and control software are introduced, and the different modulation techniques tested are described. A software simulation package is developed to assist in the control design and analysis of the drive system. Next, to establish the efficiency gains obtained by using space vector modulation in the improved drive system, an inverter with hysteresis current control is compared to the same inverter with space vector modulation in steady state and on separate driving profiles. A method for determining induction motor harmonic losses is introduced and is based on obtaining the phase current harmonics from sampled induction motor stator phase currents obtained. Using a semi-empirical loss model, the induction motor losses are compared between different pulse width modulation control strategies throughout the torque versus speed operating region. Next, several issues related to the robustness of the control design are addressed. To obtain good performance in the actual vehicle, a new method for driveline resonance compensation is developed and proven to work well through simulation and experiment. Lastly, this thesis discusses the development of a new method to compensate for the gain and phase error obtained in the feedback of the d-axis and q-axis stator flux linkages. Improved accuracy of the measured stator flux linkages will be shown to improve the field oriented controller by obtaining a more accurate measurement of the feedback electromagnetic torque. / Master of Science
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Transient thermal management simulations of complete heavy-duty vehiclesSvantesson, Einar January 2019 (has links)
Transient vehicle thermal management simulations have the potential to be an important tool to ensure long component lifetimes in heavy-duty vehicles, as well as save development costs by reducing development time. Time-resolved computational fluid dynamics simulations of complete vehicles are however typically very computationally expensive, and approximation methods must be employed to keep computational costs and turn-around times at a reasonable level. In this thesis, two transient methods are used to simulate two important time-dependent scenarios for complete vehicles; hot shutdowns and long dynamic drive cycles. An approach using a time scaling between fluid solver and thermal solver is evaluated for a short drive cycle and heat soak. A quasi-transient method, utilizing limited steady-state computational fluid dynamics data repeatedly, is used for a long drive cycle. The simulation results are validated and compared with measurements from a climatic wind tunnel. The results indicate that the time-scaling approach is appropriate when boundary conditions are not changing rapidly. Heat-soak simulations show reasonable agreement between three cases with different thermal scale factors. The quasi-transient simulations suggest that complete vehicle simulations for durations of more than one hour are feasible. The quasi-transient results partly agree with measurements, although more component temperature measurements are required to fully validate the method.
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Ökobilanz konventioneller und elektrischer FahrzeugeHofeditz, Paul 27 July 2022 (has links)
Elektroautos gelten als Hoffnungsträger, um die verkehrsbezogenen Treibhausgasemissionen in Deutschland drastisch zu reduzieren. Aus bisheriger Forschung geht hervor, dass Elektroautos über den Lebenszyklus im Durchschnitt eine geringere Menge an Treibhausgasen verursachen als konventionelle Pkw mit Verbrennungsmotoren. Jedoch betrachtet bisherige Forschung nicht, welchen Einfluss verschiedene Fahrzyklen der Pkw auf die Ökobilanz haben, was zur Folge hat, dass technologische Unterschiede, die nur auf einem Teil des Straßennetzes Anwendung finden, nicht berücksichtigt werden. Die vorliegende Arbeit untersucht den Einfluss verschiedener Fahrzyklen auf die Höhe der Treibhausgasemissionen von Elektroautos und Pkw mit Benzin- bzw. Dieselmotor. Grundlage der Emissionsbestimmung sind je ein Autobahn-Fahrzyklus und ein Stadt-Fahrzyklus, anhand derer der Strom- bzw. Kraftstoffverbrauch modelliert wird. Die Modellierung erfolgt anhand eines mikroskopischen Verbrauchsmodells, welches physikalische Kräfte, Fahrzeugparameter sowie wesentliche technologische Unterschiede berücksichtigt. Neben den Emissionen der Nutzungsphase werden die Emissionen der Produktions- und der Recyclingphase bestimmt, um den Lebenszyklus eines Pkw zu komplettieren. Die Ergebnisse bisheriger Forschung werden bestätigt, da das Elektroauto für beide Fahrzyklen geringere Emissionen aufweist. In der Stadt fällt der Unterschied deutlich höher aus, hier verursacht das Elektroauto 45,7 % weniger Treibhausgasemissionen als der Benziner bzw. 34,1 % weniger als der Diesel. Im Vergleich dazu lassen sich auf der Autobahn Treibhausgasemissionseinsparungen von 27,9 % bzw. 17,9 % realisieren, wobei die Treibhausgasemissionen in der Stadt für Elektroautos und für Autos mit Benzin- bzw. Dieselmotor höher sind als auf der Autobahn. Eine abschließende Sensitivitätsanalyse zeigt, dass ein weniger emissionsintensiver Strommix sowie die Reduktion des Leergewichts Hebel zur weiteren Reduktion der Emissionen des Elektroautos sind.
Daraus erschließt sich, dass Elektroautos im Vergleich zu Pkw mit Benzin- bzw. Dieselmotor ökobilanziell zurecht als Hoffnungsträger gelten, doch ihr Einsparpotenzial durch den Ausbau erneuerbarer Energien sowie durch die Verwendung kleinerer und leichterer Pkw in der Stadt erhöht werden kann.:Abbildungsverzeichnis . . . . . . . . . . . . . . . . .VII
Tabellenverzeichnis. . . . . . . . . . . . . . . . . IX
Abkürzungsverzeichnis. . . . . . . . . . . . . . . . . XI
Symbolverzeichnis. . . . . . . . . . . . . . . . . XIII
1 Einleitung. . . . . . . . . . . . . . . . .1
2 Aktueller Forschungsstand . . . . . . . . . . . . . . . . .3
3 Vorstellung des Konzepts der LCA . . . . . . . . . . . . . . . . .7
4 Methodik: Festlegung des Ziels und des Untersuchungsrahmens. . . . . . . . . . . . . .9
4.1 Batterieelektrische Pkw (BEV) . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.2 Pkw mit Verbrennungsmotor (ICEV) . . . . . . . . . . . . . . . . . . . . . . 11
4.3 Fahrzyklen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4 Modellierung der Produktionsphase . . . . . . . . . . . . . . . . . . . . . . . 13
4.5 Modellierung der Nutzungsphase . . . . . . . . . . . . . . . . . . . . . . . . 17
4.6 Modellierung der Recyclingphase . . . . . . . . . . . . . . . . . . . . . . . . 24
4.7 Modellierung der Aggregation der einzelnen Phasen . . . . . . . . . . . . . . 25
4.8 Betrachtete Emissionen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.9 Funktionelle Einheit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5 Sachbilanz . . . . . . . . . . . . . . . . .27
6 Ergebnisse: Wirkungsabschätzung. . . . . . . . . . . . . . . . . 31
6.1 Treibhausgasemissionen der Produktionsphase . . . . . . . . . . . . . . . . . 31
6.2 Treibhausgasemissionen der Nutzungsphase . . . . . . . . . . . . . . . . . . 33
6.3 Treibhausgasemissionen der Recyclingphase . . . . . . . . . . . . . . . . . . 35
6.4 Aggregierte Treibhausgasemissionen . . . . . . . . . . . . . . . . . . . . . . 36
7 Sensitivitätsanalyse . . . . . . . . . . . . . . . . .39
7.1 Definition und Arten von Sensitivitätsanalysen . . . . . . . . . . . . . . . . 39
7.2 Methodik der lokalen Sensitivitätsanalyse . . . . . . . . . . . . . . . . . . . 39
7.3 Variation des Leergewichts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
7.4 Variation des Luftwiderstandsbeiwertes . . . . . . . . . . . . . . . . . . . . 41
7.5 Variation der Lebensfahrleistung . . . . . . . . . . . . . . . . . . . . . . . . 42
7.6 Variation des Strommixes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
7.7 Variation des Rekuperationsgrads . . . . . . . . . . . . . . . . . . . . . . . . 46
7.8 Variation der Betriebs- und Verlustleistung . . . . . . . . . . . . . . . . . . 47
7.9 Aggregation der Ergebnisse der Sensitivitätsanalyse . . . . . . . . . . . . . . 48
8 Diskussion . . . . . . . . . . . . . . . . .51
9 Zusammenfassung und Implikationen . . . . . . . . . . . . . . . . . 53
Literaturverzeichnis. . . . . . . . . . . . . . . . . XV
Anhang . . . . . . . . . . . . . . . . . XXII
A.1 Input für die Produktionsphase . . . . . . . . . . . . . . . . . . . . . . . . . XXIII
A.2 Input für die Nutzungsphase . . . . . . . . . . . . . . . . . . . . . . . . . . XXVI
A.3 Ergebnisse der Wirkungsabschätzung . . . . . . . . . . . . . . . . . . . . . . XXVIII
A.4 Ergebnisse der Sensitivitätsanalyse . . . . . . . . . . . . . . . . . . . . . . . XXVIII / Electric cars are seen as a beacon of hope regarding the drastic reduction of greenhouse gas emissions in the transport sector in Germany. Previous research shows that electric vehicles are emitting a smaller amount of greenhouse gases than cars with a petrol or a diesel engine. However, previous research does not consider the influence of different use cases of passenger cars, which means that technological differences which only apply to parts of the road network are not accounted for. The goal of this thesis is to extend previous research by investigating the influence of different drive cycles on the amount of greenhouse gas emissions emitted by electric cars and cars with a petrol or a diesel engine. Specifically, a highway drive cycle and an urban drive cycle are used to model the consumption of electricity, petrol or diesel. In other words, it is a microscopic model utilizing physical forces, car parameters, and significant technological differences. Besides the emissions during driving the emissions caused by production and recycling are taken into account to complete the life cycle of cars. The results of previous research can be confirmed by this thesis as the amount of greenhouse gas emissions caused by electric cars is smaller than that caused by cars with petrol or diesel engines for both drive cycles. In the urban area, the difference among the investigated technologies is significantly greater over the entire lifecycle; the electric car emits 45.7 % less than a car with a petrol engine and 34.1 % less than a car with a diesel engine. In comparison, on the highway the electric car emits just 27.9 % less than a car with a petrol engine and 17.9 % less than a car with a diesel engine. A final sensitivity analysis shows that a less emission-intensive electricity mix and a reduced vehicle weight are key levers for further reducing greenhouse gas emissions of electric cars. In summary, the results of this thesis lead to the conclusion that electric cars are rightfully seen as a beacon of hope for drastically reducing greenhouse gas emissions; nevertheless, their impact could be further enhanced by expanding renewable energies and by focussing on lighter electric vehicles in urban areas.:Abbildungsverzeichnis . . . . . . . . . . . . . . . . .VII
Tabellenverzeichnis. . . . . . . . . . . . . . . . . IX
Abkürzungsverzeichnis. . . . . . . . . . . . . . . . . XI
Symbolverzeichnis. . . . . . . . . . . . . . . . . XIII
1 Einleitung. . . . . . . . . . . . . . . . .1
2 Aktueller Forschungsstand . . . . . . . . . . . . . . . . .3
3 Vorstellung des Konzepts der LCA . . . . . . . . . . . . . . . . .7
4 Methodik: Festlegung des Ziels und des Untersuchungsrahmens. . . . . . . . . . . . . .9
4.1 Batterieelektrische Pkw (BEV) . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.2 Pkw mit Verbrennungsmotor (ICEV) . . . . . . . . . . . . . . . . . . . . . . 11
4.3 Fahrzyklen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4 Modellierung der Produktionsphase . . . . . . . . . . . . . . . . . . . . . . . 13
4.5 Modellierung der Nutzungsphase . . . . . . . . . . . . . . . . . . . . . . . . 17
4.6 Modellierung der Recyclingphase . . . . . . . . . . . . . . . . . . . . . . . . 24
4.7 Modellierung der Aggregation der einzelnen Phasen . . . . . . . . . . . . . . 25
4.8 Betrachtete Emissionen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.9 Funktionelle Einheit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5 Sachbilanz . . . . . . . . . . . . . . . . .27
6 Ergebnisse: Wirkungsabschätzung. . . . . . . . . . . . . . . . . 31
6.1 Treibhausgasemissionen der Produktionsphase . . . . . . . . . . . . . . . . . 31
6.2 Treibhausgasemissionen der Nutzungsphase . . . . . . . . . . . . . . . . . . 33
6.3 Treibhausgasemissionen der Recyclingphase . . . . . . . . . . . . . . . . . . 35
6.4 Aggregierte Treibhausgasemissionen . . . . . . . . . . . . . . . . . . . . . . 36
7 Sensitivitätsanalyse . . . . . . . . . . . . . . . . .39
7.1 Definition und Arten von Sensitivitätsanalysen . . . . . . . . . . . . . . . . 39
7.2 Methodik der lokalen Sensitivitätsanalyse . . . . . . . . . . . . . . . . . . . 39
7.3 Variation des Leergewichts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
7.4 Variation des Luftwiderstandsbeiwertes . . . . . . . . . . . . . . . . . . . . 41
7.5 Variation der Lebensfahrleistung . . . . . . . . . . . . . . . . . . . . . . . . 42
7.6 Variation des Strommixes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
7.7 Variation des Rekuperationsgrads . . . . . . . . . . . . . . . . . . . . . . . . 46
7.8 Variation der Betriebs- und Verlustleistung . . . . . . . . . . . . . . . . . . 47
7.9 Aggregation der Ergebnisse der Sensitivitätsanalyse . . . . . . . . . . . . . . 48
8 Diskussion . . . . . . . . . . . . . . . . .51
9 Zusammenfassung und Implikationen . . . . . . . . . . . . . . . . . 53
Literaturverzeichnis. . . . . . . . . . . . . . . . . XV
Anhang . . . . . . . . . . . . . . . . . XXII
A.1 Input für die Produktionsphase . . . . . . . . . . . . . . . . . . . . . . . . . XXIII
A.2 Input für die Nutzungsphase . . . . . . . . . . . . . . . . . . . . . . . . . . XXVI
A.3 Ergebnisse der Wirkungsabschätzung . . . . . . . . . . . . . . . . . . . . . . XXVIII
A.4 Ergebnisse der Sensitivitätsanalyse . . . . . . . . . . . . . . . . . . . . . . . XXVIII
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Investigating The Suitability of Electrified Powertrain Alternatives for Refuse Trucks with Emphasis in The City of HamiltonToller, Jack 11 1900 (has links)
Refuse trucks, commonly referred to as garbage trucks are a critical component of a municipality’s waste management industry. Their primary purpose is to collect, transport and deposit waste from households or businesses to designated transfer sites or dumps. Historically, refuse trucks have been powered by diesel fuel. The consumption of diesel fuel paired with the frequent accelerations or decelerations between each residential household along a route attribute to high amounts of tailpipe emissions and noise pollution within neighbourhoods. There is significant opportunity to explore avenues of powertrain electrification in refuse trucks to reduce their emissions and improve energy efficiency.
To rapidly test promising powertrains, vehicle software models were developed. To accurately model the energy usage and power requirements of refuse trucks, environments for the models to operate were created. The environments were created using on-board diagnostic and positional data collected from refuse trucks in the City of Hamilton in Ontario, Canada. The data collection was done under a research collaboration between the City of Hamilton and the McMaster Automotive Resource Centre. The approaches used to develop the drive and duty cycles for the vehicle models offer some innovative approaches without the need for invasive devices to be installed.
The powertrains that were modelled includes an all-electric, ranged extended electric and conventional refuse trucks. A comparative analysis of the pump-to-wheel powertrain efficiencies were completed looking at metrics such as fuel economy, payload capacity and fuel costs. Lastly, a look at truck emissions from a well-to-wheel perspective were completed to investigate the impact of each powertrain on greenhouse gasses and the effect on air quality of their immediate surroundings. / Thesis / Master of Applied Science (MASc)
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Dynamic modeling and feedback control with mode-shifting of a two-mode electrically variable transmissionKatariya, Ashish Santosh 31 August 2012 (has links)
This thesis develops dynamic models for the two-mode FWD EVT, develops a control system based on those models that is capable of meeting driver torque demands and performing synchronous mode shifts between different EVT modes while also accommodating preferred engine operating points. The two-input two-output transmission controller proposed herein incorporates motor-generator dynamics, is based on a general state-space integral control structure, and has feedback gains determined using linear quadratic regulator (LQR) optimization.
Dynamic modeling of the vehicle is categorized as dynamic modeling of the mechanical and electrical subsystems where the mechanical subsystem consists of the planetary gear sets, the transmission and the engine whereas the electrical subsystem consists of the motor-generator units and the battery pack. A discussion of load torque is also considered as part of the mechanical subsystem. With the help of these derived dynamic models, a distinction is made between dynamic output torque and steady-state output torque.
The overall control system consisting of multiple subsystems such as the human driver, power management unit (PMU), friction brakes, combustion engine, transmission control unit (TCU) and motor-generator units is designed. The logic for synchronous mode shifts between different EVT modes is also detailed as part of the control system design. Finally, the thesis presents results for responses in individual operating modes, EVT mode shifting and a full UDDS drive cycle simulation.
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Towards sustainable urban transportation : Test, demonstration and development of fuel cell and hybrid-electric busesFolkesson, Anders January 2008 (has links)
Several aspects make today’s transport system non-sustainable: • Production, transport and combustion of fossil fuels lead to global and local environmental problems. • Oil dependency in the transport sector may lead to economical and political instability. • Air pollution, noise, congestion and land-use may jeopardise public health and quality of life, especially in urban areas. In a sustainable urban transport system most trips are made with public transport because high convenience and comfort makes travelling with public transport attractive. In terms of emissions, including noise, the vehicles are environmentally sustainable, locally as well as globally. Vehicles are energy-efficient and the primary energy stems from renewable sources. Costs are reasonable for all involved, from passengers, bus operators and transport authorities to vehicle manufacturers. The system is thus commercially viable on its own merits. This thesis presents the results from three projects involving different concept buses, all with different powertrains. The first two projects included technical evaluations, including tests, of two different fuel cell buses. The third project focussed on development of a series hybrid-bus with internal combustion engine intended for production around 2010. The research on the fuel cell buses included evaluations of the energy efficiency improvement potential using energy mapping and vehicle simulations. Attitudes to hydrogen fuel cell buses among passengers, bus drivers and bus operators were investigated. Safety aspects of hydrogen as a vehicle fuel were analysed and the use of hydrogen compared to electrical energy storage were also investigated. One main conclusion is that a city bus should be considered as one energy system, because auxiliaries contribute largely to the energy use. Focussing only on the powertrain is not sufficient. The importance of mitigating losses far down an energy conversion chain is emphasised. The Scania hybrid fuel cell bus showed the long-term potential of fuel cells, advanced auxiliaries and hybrid-electric powertrains, but technologies applied in that bus are not yet viable in terms of cost or robustness over the service life of a bus. Results from the EU-project CUTE show that hydrogen fuelled fuel cell buses are viable for real-life operation. Successful operation and public acceptance show that focus on robustness and cost in vehicle design were key success factors, despite the resulting poor fuel economy. Hybrid-electric powertrains are feasible in stop-and-go city operation. Fuel consumption can be reduced, comfort improved, noise lowered and the main power source downsized and operated less dynamically. The potential for design improvements due to flexible component packaging is implemented in the Scania hybrid concept bus. This bus and the framework for its hybrid management system are discussed in this thesis. The development of buses for a more sustainable urban transport should be made in small steps to secure technical and economical realism, which both are needed to guarantee commercialisation and volume of production. This is needed for alternative products to have a significant influence. Hybrid buses with internal combustion engines running on renewable fuel is tomorrow’s technology, which paves the way for plug-in hybrid, battery electric and fuel cell hybrid vehicles the day after tomorrow. / QC 20100722
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