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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.
41

Validation of Bus Specific Powertrain Components in STARS

Karlsson, Karl January 2007 (has links)
<p>The possibilities to simulate fuel consumption and optimize a vehicle's powertrain to fit to the customer's needs are great strengths in the competitive bus industry where fuel consumption is one of the main sales arguments. In this master's thesis, bus specific powertrain component models, used to simulate and predict fuel consumption, are validated using measured data collected from buses.</p><p>Additionally, a sensitivity analysis is made where it is investigated how errors in the powertrain parameters affect fuel consumption. After model improvements it is concluded that the library components can be used to predict fuel consumption well.</p><p>During the work, possible model uncertainties which affect fuel consumption are identified. Hence, this study may serve as foundation for further investigation of these uncertainties.</p>
42

Design, simulation, and construction of a series hybrid electric vehicle

Northcott, Daniel Ross 27 September 2007 (has links)
This thesis evaluates a series hybrid electric drivetrain design for use in parking patrol vehicles. Due to the particular attributes of this application, it is proposed that the design would improve the energy efficiency of such a vehicle. The scheme is evaluated in depth through the use of electromagnetic transient simulation tools, which are used to create a highly accurate model of the vehicle. A prototype vehicle of the same design is built, and used to verify and improve the accuracy of the simulation model. The simulation model is then used to predict the energy efficiency of the series hybrid design for parking patrol. This simulation based design strategy is proposed as a method for more rapid and cost effective design of hybrid electric vehicles.
43

Performance Modeling and Benchmark Analysis of an Advanced 4WD Series-Parallel PHEV Using Dynamic Programming

Kaban, Stefan 23 April 2015 (has links)
Advanced hybrid vehicle architectures can exploit multiple power sources and optimal control to achieve high efficiency operation. In this work, a method for generating the best-possible energy efficiency benchmark for a hybrid architecture is introduced. The benchmark program uses Dynamic Programming to analyse a reduced-fidelity MATLAB model over standard driving cycles, and bypasses vehicle controls to identify the optimal control actions and resulting fuel consumption of the Series-Parallel Multiple-Regime retrofitted PHEV of the UVic EcoCAR2 program. The simulation results indicate an optimal fuel consumption value of 4.74L/100km, in the parallel regime, compared to the stock Malibu's 8.83L/100km. The results are found to be sensitive to the allowed level of regenerative braking, with an optimal consumption value of 6.56L/100km obtained with restricted regen power limits. The parallel regime provided more efficient operation overall, especially during more aggressive driving conditions. However, the series regime provided more desirable operation during gentle driving conditions, where opportunities for regenerative braking are limited. The generated powertrain control profiles were then used to drive a higher-fidelity Simulink model. Due to the significant difference between the model structures of the MATLAB and Simulink models, comparison of results were not conclusive. A different simulation approach is required to make this proof-of-concept more useful for controls development. This research forms the foundation for further studies. / Graduate / 0540 / snkaban@gmail.com
44

Design and Control of a Unique Hydrogen Fuel Cell Plug-In Hybrid Electric Vehicle

Giannikouris, Michael January 2013 (has links)
The University of Waterloo Alternative Fuels Team (UWAFT) is a student team that designs and builds vehicles with advanced powertrains. UWAFT uses alternatives to fossil fuels because of their lower environmental impacts and the finite nature of oil resources. UWAFT participated in the EcoCAR Advanced Vehicle Technology Competition (AVTC) from 2008 to 2011. The team designed and built a Hydrogen Fuel Cell Plug-In Hybrid Electric Vehicle (FC-PHEV) and placed 3rd out of 16 universities from across North America. UWAFT design projects offer students a unique opportunity to advance and augment their core engineering knowledge with hands-on learning in a project-based environment. The design of thermal management systems for powertrain components is a case study for design engineering which requires solving open ended problems, and is a topic that is of growing importance in undergraduate engineering courses. Students participating in this design project learn to develop strategies to overcome uncertainty and to evaluate and execute designs that are not as straightforward as those in a textbook. Electrical and control system projects require students to introduce considerations for reliability and robustness into their design processes that typically only focus on performance and function, and to make decisions that balance these considerations in an environment where these criteria impact the successful outcome of the project. The consequences of a failure or unreliable design also have serious safety implications, particularly in the implementation of powertrain controls. Students integrate safety into every step of control system design, using tools to identify and link together component failures and vehicle faults, to design detection and mitigation strategies for safety-critical failures, and to validate these strategies in real-time simulations. Student teams have the opportunity to offer a rich learning environment for undergraduate engineering students. The design projects and resources that they provide can significantly advance student knowledge, experience, and skills in a way that complements the technical knowledge gained in the classroom. Finding ways to provide these experiences to more undergraduate students, either outside or within existing core courses, has the potential to enhance the value of program graduates.
45

Design, simulation, and construction of a series hybrid electric vehicle

Northcott, Daniel Ross 27 September 2007 (has links)
This thesis evaluates a series hybrid electric drivetrain design for use in parking patrol vehicles. Due to the particular attributes of this application, it is proposed that the design would improve the energy efficiency of such a vehicle. The scheme is evaluated in depth through the use of electromagnetic transient simulation tools, which are used to create a highly accurate model of the vehicle. A prototype vehicle of the same design is built, and used to verify and improve the accuracy of the simulation model. The simulation model is then used to predict the energy efficiency of the series hybrid design for parking patrol. This simulation based design strategy is proposed as a method for more rapid and cost effective design of hybrid electric vehicles.
46

A Hardware-in-the-Loop Test Platform for Planetary Rovers

Yue, Bonnie January 2011 (has links)
Hardware-in-the-Loop (HIL) test platform for planetary rovers was designed, fabricated and tested in the present work. The ability for planetary rover designers and mission planners to estimate the rover’s performance through software simulation is crucial. HIL testing can further the benefits of software simulations by allowing designers to incorporate hardware components within traditionally pure software simulations. This provides more accurate performance results without having access to all hardware components, as would be required for a full prototype testing. The test platform is designed with complete modularity such that different types of tests can be performed for varying types of planetary rovers and in different environments. For demonstrating the operation of the test platform, however, the power system operation of a solar powered rover was examined. The system consists of solar panels, a solar charge controller, a battery, a DC/DC converter, a DC motor and a flywheel. In addition, a lighting system was designed to simulate the solar radiation conditions solar panels would experience throughout a typical day. On the software side, a library of component models was developed within MapleSim and model parameters were tuned to match the hardware on the test bench. A program was developed for real-time simulations within Labview allowing communication between hardware components and software models. This program consists of all the component models, hardware controls and data acquisitioning. The GUI of this program allows users to select which component is to be tested and which component is to be simulated, change model parameters as well as see real time sensor measurements for each component. A signal scaling technique based on non-dimensionalization is also presented, which can be used in an HIL application for obtain scaling factors to ensure dynamic similarity between two systems. A demonstration of power estimation was performed using the pure software model simulations as well as the pure hardware testing. Hardware components were then added into the software simulation progressively with results showing better accuracy as hardware is added. The rover’s power flow was also estimated under different load conditions and seasonal variation. These simulations clearly demonstrate the effectiveness of an HIL platform for testing a rover’s hardware performance.
47

Effect of Temperature on Lithium-Iron Phosphate Battery Performance and Plug-in Hybrid Electric Vehicle Range

Lo, Joshua January 2013 (has links)
Increasing pressure from environmental, political and economic sources are driving the development of an electric vehicle powertrain. The advent of hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs) bring significant technological and design challenges. The success of electric vehicle powertrains depends heavily on the robustness and longevity of the on-board energy storage system or battery. Currently, lithium-ion batteries are the most suitable technology for use in electrified vehicles. The majority of literature and commercially available battery performance data assumes a working environment that is at room temperature. However, an electrified vehicle battery will need to perform under a wide range of temperatures, including the extreme cold and hot environments. Battery performance changes significantly with temperature, so the effects of extreme temperature operation must be understood and accounted for in electrified vehicle design. In order to meet the aggressive development schedules of the automotive industry, electrified powertrain models are often employed. The development of a temperature-dependent battery model with an accompanying vehicle model would greatly enable model based design and rapid prototyping efforts. This paper empirically determines the performance characteristics of an A123 lithium iron-phosphate battery, re-parameterizes the battery model of a vehicle powertrain model, and estimates the electric range of the modeled vehicle at various temperatures. The battery and vehicle models will allow future development of cold-weather operational strategies. As expected the vehicle range is found to be far lower with a cold battery back. This effect is seen to be much more pronounced in the aggressive US06 drive cycle where the all-electric range was found to be 44% lower at -20°C than at 25°C. Also it was found that there was minimal impact of temperature on range above 25°C
48

Development of Push Control Strategy for Diesel-Electric Powertrains

Bodin, Johannes January 2018 (has links)
In diesel-electric powertrains, the wheels are mechanically decoupled from the internal combustion engine (ICE). The conventional control approach for such a powertrain is to let the driver control the traction motor while the ICE realizes speed control, causing power to be pulled through the powertrain. An alternative approach is to push power forward by letting the driver control the ICE instead. In this thesis, a conceptual simulation model of a diesel-electric powertrain is compiled and the charcteristics of this novel approach investigated. It is concluded that the new approach makes full ICE power utilization possible even with engine performance reductions present, and also that it handles load prioritization in a natural way. However, takeoff from standstill and low-speed driving become difficult due to the effective gear ratio growing towards infinity for decreasing vehicle speed, causing high traction torques at low speed.
49

Modeling, optimization and environmental assessment of electrified marine vessels

Manouchehrinia, Babak 21 December 2018 (has links)
Electrified Vehicles (EVs), including Hybrid Electric Vehicles (HEVs) and Pure Electric Vehicles (PEVs), can provide substantial improvements in energy efficiency, emission reduction, and lifecycle cost over conventional vehicles solely powered by Internal Combustion Engines (ICE). Progress on electrification of marine vessels has been made, but the pace has been impacted by factors such as the different operational load profile of vessels, relatively small production levels and longer or varied lifetimes. In this dissertation, hybrid electric and pure electric propulsion system designs for fishing boats and passenger ferries are studied based on in-field acquired operational data. A new integrated marine propulsion system modeling and simulation method and a dedicated mobile data acquisition system have been introduced to analyze the energy efficiency, emission reduction, and lifecycle costs of new or retrofitted fishing boats and passenger ferries with hybrid electric and pure electric powertrains. Following the automotive industry Model Based Design (MBD) approach, modeling and simulation of electrified vessels using the acquired operation profile have been carried out using backward and forward-facing methods. Series hybrid electric and pure electric powertrain system designs with powertrain component models and rule-based system control, including a properly sized electric Energy Storage System (ESS) with a Supercapacitor (SC) or battery, have been studied. The total CO2 equivalent (CO2e) or Greenhouse Gas (GHG) emissions and lifecycle costs of various new, electrified vessel propulsion system designs have been evaluated. Clean propulsion system solutions for fishing boats and passenger ferries with detailed powertrain system and control system designs are given which provide a foundation for further research and development. This dissertation also addresses the environmental impact of Natural Gas (NG) as a transportation fuel, particularly for marine transportation use. A systematic evaluation of GHG emissions is provided for the upstream fuel supply chain of natural gas fuel in British Columbia (BC), Canada. The Liquefied Natural Gas (LNG) lifecycle GHG emissions produced in both the upstream supply chain and the downstream vessel propulsion are estimated quantitatively using manufacturer data and propulsion system models of marine vessels. Extensive data have been collected from oil and gas companies that have active operations in BC to determine the upstream supply chain GHG emissions of the NG fuel under three scenarios. The energy efficiency and emissions of natural gas engines are compared with traditional diesel fuel marine engines and generators. The results obtained indicate that LNG fuel can lower CO2e by 10% to 28% with reduced local air pollutants such as sulfur oxides and particulates, compared to conventional diesel fuel. However, engine methane slip during combustion should be monitored as it can have a significant impact on the GHG emissions and so offset the environmental benefits of LNG. / Graduate
50

Validation of Bus Specific Powertrain Components in STARS

Karlsson, Karl January 2007 (has links)
The possibilities to simulate fuel consumption and optimize a vehicle's powertrain to fit to the customer's needs are great strengths in the competitive bus industry where fuel consumption is one of the main sales arguments. In this master's thesis, bus specific powertrain component models, used to simulate and predict fuel consumption, are validated using measured data collected from buses. Additionally, a sensitivity analysis is made where it is investigated how errors in the powertrain parameters affect fuel consumption. After model improvements it is concluded that the library components can be used to predict fuel consumption well. During the work, possible model uncertainties which affect fuel consumption are identified. Hence, this study may serve as foundation for further investigation of these uncertainties.

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